nih-gov/pubmed.ncbi.nlm.nih.gov/22550198/index.html

4117 lines
No EOL
152 KiB
HTML
Raw Permalink Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<!DOCTYPE html>
<html lang="en" >
<head itemscope itemtype="http://schema.org/WebPage" prefix="og: http://ogp.me/ns#" >
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<!-- Mobile properties -->
<meta name="HandheldFriendly" content="True">
<meta name="MobileOptimized" content="320">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<link rel="preconnect" href="https://cdn.ncbi.nlm.nih.gov">
<link rel="preconnect" href="https://www.ncbi.nlm.nih.gov">
<link rel="preconnect" href="https://www.google-analytics.com">
<link rel="stylesheet" href="https://cdn.ncbi.nlm.nih.gov/pubmed/277eb475-38df-4990-a0ee-0080b04e86fc/CACHE/css/output.ba8099dd2df4.css" type="text/css">
<link rel="stylesheet" href="https://cdn.ncbi.nlm.nih.gov/pubmed/277eb475-38df-4990-a0ee-0080b04e86fc/CACHE/css/output.452c70ce66f7.css" type="text/css">
<link rel="stylesheet" href="https://cdn.ncbi.nlm.nih.gov/pubmed/277eb475-38df-4990-a0ee-0080b04e86fc/CACHE/css/output.7bf600913d6e.css" type="text/css">
<link rel="stylesheet" href="https://cdn.ncbi.nlm.nih.gov/pubmed/277eb475-38df-4990-a0ee-0080b04e86fc/CACHE/css/output.0bfa59184c7a.css" type="text/css">
<title>Characteristics of clinical trials registered in ClinicalTrials.gov, 2007-2010 - PubMed</title>
<link rel="preload" as="font" href="https://cdn.ncbi.nlm.nih.gov/pubmed/277eb475-38df-4990-a0ee-0080b04e86fc/uswds/dist/fonts/merriweather-bold-webfont.woff2" type="font/woff2" crossorigin />
<!-- Favicons -->
<link rel="shortcut icon" type="image/ico" href="https://cdn.ncbi.nlm.nih.gov/coreutils/nwds/img/favicons/favicon.ico" />
<link rel="icon" type="image/png" href="https://cdn.ncbi.nlm.nih.gov/coreutils/nwds/img/favicons/favicon.png" />
<!-- 192x192, as recommended for Android
http://updates.html5rocks.com/2014/11/Support-for-theme-color-in-Chrome-39-for-Android
-->
<link rel="icon" type="image/png" sizes="192x192" href="https://cdn.ncbi.nlm.nih.gov/coreutils/nwds/img/favicons/favicon-192.png" />
<!-- 57x57 (precomposed) for iPhone 3GS, pre-2011 iPod Touch and older Android devices -->
<link rel="apple-touch-icon-precomposed" href="https://cdn.ncbi.nlm.nih.gov/coreutils/nwds/img/favicons/favicon-57.png">
<!-- 72x72 (precomposed) for 1st generation iPad, iPad 2 and iPad mini -->
<link rel="apple-touch-icon-precomposed" sizes="72x72" href="https://cdn.ncbi.nlm.nih.gov/coreutils/nwds/img/favicons/favicon-72.png">
<!-- 114x114 (precomposed) for iPhone 4, 4S, 5 and post-2011 iPod Touch -->
<link rel="apple-touch-icon-precomposed" sizes="114x114" href="https://cdn.ncbi.nlm.nih.gov/coreutils/nwds/img/favicons/favicon-114.png">
<!-- 144x144 (precomposed) for iPad 3rd and 4th generation -->
<link rel="apple-touch-icon-precomposed" sizes="144x144" href="https://cdn.ncbi.nlm.nih.gov/coreutils/nwds/img/favicons/favicon-144.png">
<!-- For Pinger + Google Optimize integration (NS-820) -->
<meta name="ncbi_sg_optimize_id" content="">
<!-- Mobile browser address bar color -->
<meta name="theme-color" content="#20558a">
<!-- Preserve the Referrer when going from HTTPS to HTTP -->
<meta name="referrer" content="origin-when-cross-origin">
<meta name="ncbi_pinger_gtm_track" content="true"/>
<!-- Logging params: Pinger defaults -->
<meta name="ncbi_app" content="pubmed" />
<meta name="ncbi_db" content="pubmed" />
<meta name="ncbi_phid" content="BA3600017CB8DF05000027821B2D68C1.1.m_7" />
<meta name="ncbi_pinger_stat_url" content="https://www.ncbi.nlm.nih.gov/stat" />
<meta name="log_category" content="literature" />
<meta name="ncbi_cost_center" content="pubmed" />
<!-- Logging params: Pinger custom -->
<meta name="ncbi_pdid" content="abstract" />
<meta name="log_op" content="retrieve" />
<meta name="uid" content="22550198" />
<meta name="ncbi_uid" content="22550198" />
<meta name="log_displayeduids" content="22550198" />
<meta name="log_source_db" content="pubmed" />
<meta name="log_icons_present" content="true" />
<meta name="ncbi_search_id" content="baKULWJvIKEmjmzpBLKMtQ:647ff15141af266103a93759ef71cd80" />
<meta name="ncbi_adj_nav_search_id" content="O76G0u_mXSrhAito6o4KYg:647ff15141af266103a93759ef71cd80" />
<!-- Social meta tags for unfurling urls -->
<meta name="description" content="Clinical trials registered in ClinicalTrials.gov are dominated by small trials and contain significant heterogeneity in methodological approaches, including reported use of randomization, blinding, and DMCs."><meta name="keywords" content="pmid:22550198, doi:10.1001/jama.2012.3424, Research Support, U.S. Gov&#x27;t, P.H.S., Robert M Califf, Deborah A Zarin, Asba Tasneem, Cardiovascular Diseases / therapy, Clinical Trials as Topic / standards*, Clinical Trials as Topic / statistics &amp; numerical data*, Databases, Factual*, Drug Industry, Humans, Mental Disorders / therapy, National Institutes of Health (U.S.), Neoplasms / therapy, Randomized Controlled Trials as Topic, Registries / statistics &amp; numerical data*, Research Design, Research Support as Topic, Sample Size, United States, PubMed Abstract, NIH, NLM, NCBI, National Institutes of Health, National Center for Biotechnology Information, National Library of Medicine, MEDLINE"><meta name="robots" content="index,nofollow,noarchive"><meta property="og:title" content="Characteristics of clinical trials registered in ClinicalTrials.gov, 2007-2010 - PubMed"><meta property="og:url" content="https://pubmed.ncbi.nlm.nih.gov/22550198/"><meta property="og:description" content="Clinical trials registered in ClinicalTrials.gov are dominated by small trials and contain significant heterogeneity in methodological approaches, including reported use of randomization, blinding, and DMCs."><meta property="og:image" content="https://cdn.ncbi.nlm.nih.gov/pubmed/persistent/pubmed-meta-image-v2.jpg"><meta property="og:image:secure_url" content="https://cdn.ncbi.nlm.nih.gov/pubmed/persistent/pubmed-meta-image-v2.jpg"><meta property="og:type" content="website"><meta property="og:site_name" content="PubMed"><meta name="twitter:domain" content="pubmed.ncbi.nlm.nih.gov"><meta name="twitter:card" content="summary_large_image"><meta name="twitter:title" content="Characteristics of clinical trials registered in ClinicalTrials.gov, 2007-2010 - PubMed"><meta name="twitter:url" content="https://pubmed.ncbi.nlm.nih.gov/22550198/"><meta name="twitter:description" content="Clinical trials registered in ClinicalTrials.gov are dominated by small trials and contain significant heterogeneity in methodological approaches, including reported use of randomization, blinding, and DMCs."><meta name="twitter:image" content="https://cdn.ncbi.nlm.nih.gov/pubmed/persistent/pubmed-meta-image-v2.jpg">
<!-- OpenSearch XML -->
<link rel="search" type="application/opensearchdescription+xml" href="https://cdn.ncbi.nlm.nih.gov/pubmed/persistent/opensearch.xml" title="PubMed search">
<!-- Disables severely broken elements when no JS -->
<noscript>
<link rel="stylesheet" type="text/css" href="https://cdn.ncbi.nlm.nih.gov/pubmed/277eb475-38df-4990-a0ee-0080b04e86fc/core/no-script.css">
</noscript>
<meta name="citation_title" content="Characteristics of clinical trials registered in ClinicalTrials.gov, 2007-2010">
<meta name="citation_authors" content="Califf RM;Zarin DA;Kramer JM;Sherman RE;Aberle LH;Tasneem A;">
<meta name="citation_date" content="05/02/2012">
<meta name="citation_publisher" content="JAMA">
<meta name="citation_journal_title" content="JAMA">
<meta name="citation_pmid" content="22550198">
<meta name="citation_abstract_html_url" content="https://pubmed.ncbi.nlm.nih.gov/22550198/">
<meta name="citation_volume" content="307">
<meta name="citation_issue" content="17">
<meta name="citation_doi" content="10.1001/jama.2012.3424">
<meta name="citation_issn" content="1538-3598">
<link rel="canonical" href="https://pubmed.ncbi.nlm.nih.gov/22550198/" />
</head>
<body >
<noscript>
<div class="no-script-banner" id="no-script-banner">
<div class="warning-message">
<div class="warning-message-text">
This site needs JavaScript to work properly. Please enable it to take advantage of the complete set of features!
</div>
</div>
</div>
</noscript>
<div class="no-session-banner" id="no-session-banner" hidden>
<div class="warning-message">
<div class="warning-message-text">
Clipboard, Search History, and several other advanced features are temporarily unavailable.
</div>
<button class="close-banner-button"
title="Close Clipboard and Search History not available warning banner"
ref="linksrc=close_no_session_banner"
aria-controls="no-session-banner"
aria-label="Close Clipboard and Search History not available warning banner"
aria-expanded="true">
</button>
</div>
</div>
<a class="usa-skipnav" href="#article-details">
Skip to main page content
</a>
<!-- ========== BEGIN HEADER ========== -->
<section class="usa-banner">
<div class="usa-accordion">
<header class="usa-banner-header">
<div class="usa-grid usa-banner-inner">
<img src="https://www.ncbi.nlm.nih.gov/coreutils/uswds/img/favicons/favicon-57.png" alt="U.S. flag" />
<p>An official website of the United States government</p>
<button
class="usa-accordion-button usa-banner-button"
aria-expanded="false"
aria-controls="gov-banner-top"
>
<span class="usa-banner-button-text">Here's how you know</span>
</button>
</div>
</header>
<div
class="usa-banner-content usa-grid usa-accordion-content"
id="gov-banner-top"
>
<div class="usa-banner-guidance-gov usa-width-one-half">
<img
class="usa-banner-icon usa-media_block-img"
src="https://www.ncbi.nlm.nih.gov/coreutils/uswds/img/icon-dot-gov.svg"
alt="Dot gov"
/>
<div class="usa-media_block-body">
<p>
<strong>The .gov means its official.</strong>
<br />
Federal government websites often end in .gov or .mil. Before
sharing sensitive information, make sure youre on a federal
government site.
</p>
</div>
</div>
<div class="usa-banner-guidance-ssl usa-width-one-half">
<img
class="usa-banner-icon usa-media_block-img"
src="https://www.ncbi.nlm.nih.gov/coreutils/uswds/img/icon-https.svg"
alt="Https"
/>
<div class="usa-media_block-body">
<p>
<strong>The site is secure.</strong>
<br />
The <strong>https://</strong> ensures that you are connecting to the
official website and that any information you provide is encrypted
and transmitted securely.
</p>
</div>
</div>
</div>
</div>
</section>
<div class="usa-overlay"></div>
<header class="ncbi-header" role="banner" data-section="Header">
<div class="usa-grid">
<div class="usa-width-one-whole">
<div class="ncbi-header__logo">
<a href="https://www.ncbi.nlm.nih.gov/" class="logo" aria-label="NCBI Logo" data-ga-action="click_image" data-ga-label="NIH NLM Logo">
<img src="https://www.ncbi.nlm.nih.gov/coreutils/nwds/img/logos/AgencyLogo.svg" alt="NIH NLM Logo" />
</a>
</div>
<div class="ncbi-header__account">
<a id="account_login" href="https://account.ncbi.nlm.nih.gov" class="usa-button header-button" style="display:none" data-ga-action="open_menu" data-ga-label="account_menu">Log in</a>
<button id="account_info" class="header-button" style="display:none"
aria-controls="account_popup">
<span class="fa fa-user" aria-hidden="true"></span>
<span class="username desktop-only" aria-hidden="true" id="uname_short"></span>
<span class="sr-only">Show account info</span>
</button>
</div>
<div class="ncbi-popup-anchor">
<div class="ncbi-popup account-popup" id="account_popup" aria-hidden="true">
<div class="ncbi-popup-head">
<button class="ncbi-close-button" data-ga-action="close_menu" data-ga-label="account_menu"><span class="fa fa-times"></span><span class="usa-sr-only">Close</span></button>
<h4>Account</h4>
</div>
<div class="account-user-info">
Logged in as:<br/>
<b><span class="username" id="uname_long">username</span></b>
</div>
<div class="account-links">
<ul class="usa-unstyled-list">
<li><a id="account_myncbi" href="/myncbi/" class="set-base-url" data-ga-action="click_menu_item" data-ga-label="account_myncbi">Dashboard</a></li>
<li><a id="account_pubs" href="/myncbi/collections/bibliography/" class="set-base-url" data-ga-action="click_menu_item" data-ga-label="account_pubs">Publications</a></li>
<li><a id="account_settings" href="/account/settings/" class="set-base-url" data-ga-action="click_menu_item" data-ga-label="account_settings">Account settings</a></li>
<li><a id="account_logout" href="/account/signout/" class="set-base-url" data-ga-action="click_menu_item" data-ga-label="account_logout">Log out</a></li>
</ul>
</div>
</div>
</div>
</div>
</div>
</header>
<div role="navigation" aria-label="access keys">
<a id="nws_header_accesskey_0" href="https://www.ncbi.nlm.nih.gov/guide/browsers/#ncbi_accesskeys" class="usa-sr-only" accesskey="0" tabindex="-1">Access keys</a>
<a id="nws_header_accesskey_1" href="https://www.ncbi.nlm.nih.gov" class="usa-sr-only" accesskey="1" tabindex="-1">NCBI Homepage</a>
<a id="nws_header_accesskey_2" href="/myncbi/" class="set-base-url usa-sr-only" accesskey="2" tabindex="-1">MyNCBI Homepage</a>
<a id="nws_header_accesskey_3" href="#maincontent" class="usa-sr-only" accesskey="3" tabindex="-1">Main Content</a>
<a id="nws_header_accesskey_4" href="#" class="usa-sr-only" accesskey="4" tabindex="-1">Main Navigation</a>
</div>
<section data-section="Alerts">
<div class="ncbi-alerts-placeholder"></div>
</section>
<!-- ========== END HEADER ========== -->
<a id="maincontent" aria-label="Main page content below" role="navigation"></a>
<input type="hidden" name="csrfmiddlewaretoken" value="rflWEJ0KQSqzRd066f1777SfRtZYb5BmI251hzt6qtd3LE6WJyE9BfoTpxHa4G9G">
<form action="/" method="get" autocomplete="off" class="usa-search usa-search-big search-form content-page-layout" id="search-form" role="search">
<div class="inner-wrap">
<a class="pubmed-logo"
aria-label="Pubmed Logo"
href="/"
data-ga-category="featured_link"
data-ga-action="pubmed_logo">
<img src="https://cdn.ncbi.nlm.nih.gov/pubmed/277eb475-38df-4990-a0ee-0080b04e86fc/core/images/pubmed-logo-blue.svg" alt="pubmed logo" />
</a>
<a href="#" class="search-input-trigger" data-alt-title="Hide search bar" title="Show search bar" aria-label="Show search bar">
</a>
<div role="search" class="search-input">
<div class="form-field ">
<label class="usa-sr-only" for="id_term">
Search:
</label>
<input
type="search"
name="term"
data-skip-ie-scroll-to-top=""
data-replace-term-with-exact=""
data-exact-query=""
placeholder=""
class="term-input"
required="required"
id="id_term"/><a href="#" class="clear-btn" aria-label="Clear search input" title="Clear search input" role="button" data-pinger-ignore></a><button type="submit" class="search-btn" aria-label="Search" disabled data-pinger-ignore><span class="usa-search-submit-text">Search</span></button>
</div>
</div>
<!-- Create alert and Create RSS are buttons that look like links -->
<!-- Better for them to look like buttons but no space -->
<div class="search-links-wrapper content-page-layout">
<div class="search-links">
<a href="/advanced/"
class="search-input-link adv-search-link"
data-ga-category="featured_link"
data-ga-action="adv_search">Advanced</a>
<a href="/clipboard/"
class="search-input-link clipboard-link hidden"
data-ga-category="featured_link"
data-ga-action="clipboard">
Clipboard <span class="amount-in-clipboard"></span>
</a>
</div>
<span class="search-input-link user-guide-link" role="navigation" aria-label="User guide">
<a href="/help/"
data-ga-category="featured_link"
data-ga-action="user_guide">
User Guide
</a>
</span>
</div>
</div>
</form>
<div id="article-page-header">
<div id="article-top-actions-bar" class="article-top-actions-bar">
<div class="inner-wrap">
<div class="actions-container">
<div class="return-to-search">
</div>
<div class="multiple-results-actions " role="region" aria-label="save, email, send to">
<button id="save-results-panel-trigger"
type="button"
class="save-results save-results-panel-trigger"
aria-expanded="false"
aria-controls="save-action-panel"
data-ga-category="save_share"
data-ga-action="save"
data-ga-label="open">
Save
</button><button id="email-results-panel-trigger"
type="button"
class="email-results email-results-panel-trigger"
aria-expanded="false"
aria-controls="email-action-panel"
data-ga-category="save_share"
data-ga-action="email"
data-ga-label="open">
Email
</button><div class="more-actions dropdown-block"><button id="more-actions-trigger"
type="button"
class="trigger more-actions-trigger"
ref="linksrc=show_moreactions_btn"
aria-label="Send to"
aria-controls="more-actions-dropdown">Send to</button><div id="more-actions-dropdown" class="dropdown dropdown-container" hidden><div class="content"><ul class="more-actions-links"><li><a class="clipboard-panel-trigger dropdown-block-link "
href="#"
role="button"
data-ga-category="save_share"
data-ga-action="clipboard"
data-ga-label="send">
Clipboard
</a></li><li><a role="button" class="dropdown-block-link bibliography-trigger-target" href="https://account.ncbi.nlm.nih.gov/?back_url=https%3A%2F%2Fpubmed.ncbi.nlm.nih.gov%2F22550198%2F%23open-bibliography-panel">My Bibliography</a></li><li><a role="button" class="dropdown-block-link collections-trigger-target" href="https://account.ncbi.nlm.nih.gov/?back_url=https%3A%2F%2Fpubmed.ncbi.nlm.nih.gov%2F22550198%2F%23open-collections-panel">Collections</a></li><li><a role="button" class="citation-manager-panel-trigger dropdown-block-link citation-manager-trigger-target" href="#">Citation manager</a></li></ul></div></div></div>
</div>
<div class="display-options" data-format-key="format"
data-default-format-value="abstract"
data-current-format-value="abstract" role="region">
<button
class="trigger usa-button"
title="Change format"
data-ga-category="display_options"
data-ga-action="display_options_dialog">
<span class="button-label">Display options</span>
</button>
<div class="dropdown" hidden>
<div class="title">
Display options
</div>
<div class="content">
<div class="format-container">
<span class="option-label">
Format
</span>
<select name="format" data-initial-value="abstract" aria-label="Display format" id="article-display-format">
<option value="abstract">Abstract</option>
<option value="pubmed">PubMed</option>
<option value="pmid">PMID</option>
</select>
</div>
</div>
</div>
</div>
<input type="hidden" name="csrfmiddlewaretoken" value="rflWEJ0KQSqzRd066f1777SfRtZYb5BmI251hzt6qtd3LE6WJyE9BfoTpxHa4G9G">
</div>
</div>
</div>
<div id="article-panels-container" class="article-panels-container">
<div id="save-action-panel" class="save-action-panel action-panel" aria-hidden="true">
<div class="inner-wrap">
<h2 class="action-panel-heading">
Save citation to file
</h2>
<form id="save-action-panel-form"
class="action-panel-content action-form"
action="/results-export-ids/"
data-by-search-action="/results-export-search-data/"
data-by-ids-action="/results-export-ids/"
method="post"
data-by-search-method="post"
data-by-ids-method="post">
<input type="hidden" name="csrfmiddlewaretoken" value="rflWEJ0KQSqzRd066f1777SfRtZYb5BmI251hzt6qtd3LE6WJyE9BfoTpxHa4G9G">
<div class="action-panel-control-wrap">
<label for="save-action-format" class="action-panel-label">
Format:
</label>
<select id="save-action-format" name="results-format" class="action-panel-selector">
<option value="summary-text">Summary (text)</option>
<option value="pubmed-text">PubMed</option>
<option value="pmid">PMID</option>
<option value="abstract">Abstract (text)</option>
<option value="csv">CSV</option>
</select>
</div>
<div class="action-panel-actions">
<button class="action-panel-submit"
type="submit"
data-loading-label="Saving..."
data-ga-category="save_share"
data-ga-action="save"
data-ga-label="save">
Create file
</button>
<button class="action-panel-cancel"
aria-label="Close 'Save citations to file' panel"
ref="linksrc=close_save_panel"
aria-controls="save-action-panel"
aria-expanded="false"
data-ga-category="save_share"
data-ga-action="save"
data-ga-label="cancel">
Cancel
</button>
</div>
</form>
</div>
</div>
<div id="email-action-panel"
class="email-action-panel action-panel"
aria-hidden="true"
data-recaptcha-script-url="https://www.recaptcha.net/recaptcha/enterprise.js?render=explicit&onload=onloadCaptchaCallback"
data-recaptcha-enabled="true">
<div class="inner-wrap">
<h2 class="action-panel-heading">
Email citation
</h2>
<form id="email-action-panel-form"
class="action-panel-content action-form"
action="/send-email/"
data-by-search-action="/results-export-email-by-search-data/"
data-by-ids-action="/send-email/"
data-by-search-method="post"
data-by-ids-method="post"
method="post"
>
<input type="hidden" name="csrfmiddlewaretoken" value="rflWEJ0KQSqzRd066f1777SfRtZYb5BmI251hzt6qtd3LE6WJyE9BfoTpxHa4G9G">
<div class="action-panel-control-wrap">
<span class="action-panel-label">
Subject:
</span>
<span class="email-subject" id="email-subject" aria-label="Email subject">1 selected item: 22550198 - PubMed</span>
<input type="hidden" name="email-subject" value="1 selected item: 22550198"/>
<input type="hidden" name="email-subject-hash" value="10f88c725577e82a9997128f1a1651a96bbeb88044875f7c338b75fd148635dd"/>
</div>
<div class="action-panel-control-wrap">
<label for="email-to" class="action-panel-label required-field-asterisk">
To:
</label>
<input type="email" aria-label="Recipient Email Address" placeholder="email@example.com" id="email-to" class="email-to" pattern="^[a-zA-Z0-9_.+-]+@[a-zA-Z0-9-]+\.[a-zA-Z0-9-.]+$" maxlength="100" required>
</div>
<div class="action-panel-control-wrap">
<label for="email-from" class="action-panel-label">
From:
</label>
<input type="email" aria-label="Sender Email Address" placeholder="email@example.com" id="email-from" class="email-from" pattern="^[a-zA-Z0-9_.+-]+@[a-zA-Z0-9-]+\.[a-zA-Z0-9-.]+$" maxlength="256">
</div>
<div class="action-panel-control-wrap">
<label for="email-citation-format" class="action-panel-label">
Format:
</label>
<select id="email-citation-format" name="citation-format" class="action-panel-selector email-citation-format">
<option selected="selected" value="summary">Summary</option>
<option value="summary-text">Summary (text)</option>
<option value="abstract">Abstract</option>
<option value="abstract-text">Abstract (text)</option>
</select>
</div>
<div class="include-supplemental-container">
<input type="checkbox" aria-label="Include MeSH and other data" name="include-supplemental" id="email-include-supplemental" class="email-include-supplemental">
<label for="email-include-supplemental" class="email-include-supplemental-label">MeSH and other data</label>
</div>
<div class="form-field recaptcha ">
<div class="g-recaptcha" id="id-recaptcha" data-sitekey="6LfsWHMdAAAAAClKbtOpjQ2pMjgsGxvv7NdZW9uI"></div>
</div>
<div id="captcha-error-message" class="usa-input-error-message captcha-validation-message" role="alert"></div>
<div class="action-panel-actions">
<button class="action-panel-submit"
type="submit"
data-loading-label="Sending..."
data-ga-category="save_share"
data-ga-action="email"
data-ga-label="send">
Send email
</button>
<button class="action-panel-cancel"
aria-label="Close 'Email citations' panel"
ref="linksrc=close_email_panel"
aria-controls="email-action-panel"
aria-expanded="false"
data-ga-category="save_share"
data-ga-action="email"
data-ga-label="cancel">
Cancel
</button>
</div>
<input type="hidden" name="email-search-details" value="" />
<input type="hidden" name="email-search-details-hash" value="0e42663a6c3bd85498fcb88798998fed7bfdc45d457db35281e41afe13cc0524" />
</form>
</div>
</div>
<div id="collections-action-panel"
class="collections-action-panel action-panel in-progress-dots-panel"
aria-hidden="true"
data-collections-open-panel-enabled="false"
data-collections-open-panel-url-hash="#open-collections-panel">
<div class="inner-wrap">
<h3 class="action-panel-heading">
Add to Collections
</h3>
<form id="collections-action-panel-form"
class="collections-action-panel-form action-panel-content action-form action-panel-smaller-selectors"
data-existing-collections-url="/list-existing-collections/"
data-add-to-existing-collection-url="/add-to-existing-collection/"
data-create-and-add-to-new-collection-url="/create-and-add-to-new-collection/"
data-get-article-ids-by-search-url="/get-article-ids-by-search/"
data-myncbi-max-collection-name-length="100"
data-add-to-collection-max-amount="1000"
data-collections-root-url="https://www.ncbi.nlm.nih.gov/myncbi/collections/">
<input type="hidden" name="csrfmiddlewaretoken" value="rflWEJ0KQSqzRd066f1777SfRtZYb5BmI251hzt6qtd3LE6WJyE9BfoTpxHa4G9G">
<div class="choice-group" role="radiogroup">
<ul class="radio-group-items">
<li>
<input type="radio"
id="collections-action-panel-new"
class="collections-new"
name="collections"
value="new"
data-ga-category="save_share"
data-ga-action="collections"
data-ga-label="collections_radio_new">
<label for="collections-action-panel-new">Create a new collection</label>
</li>
<li>
<input type="radio"
id="collections-action-panel-existing"
class="collections-existing"
name="collections"
value="existing"
checked="true"
data-ga-category="save_share"
data-ga-action="collections"
data-ga-label="collections_radio_existing">
<label for="collections-action-panel-existing">Add to an existing collection</label>
</li>
</ul>
</div>
<div class="controls-wrapper">
<div class="action-panel-control-wrap new-collections-controls">
<label for="collections-action-panel-add-to-new" class="action-panel-label required-field-asterisk">
Name your collection:
</label>
<input
type="text"
name="add-to-new-collection"
id="collections-action-panel-add-to-new"
class="collections-action-add-to-new"
pattern="[^&quot;&amp;=&lt;&gt;\/]*" title="The following characters are not allowed in the Name field: &quot;&amp;=&lt;&gt;/"
maxlength="100"
data-ga-category="save_share"
data-ga-action="create_collection"
data-ga-label="non_favorties_collection">
<div class="collections-new-name-too-long usa-input-error-message selection-validation-message">
Name must be less than 100 characters
</div>
</div>
<div class="action-panel-control-wrap existing-collections-controls">
<label for="collections-action-panel-add-to-existing" class="action-panel-label">
Choose a collection:
</label>
<select id="collections-action-panel-add-to-existing"
class="action-panel-selector collections-action-add-to-existing"
data-ga-category="save_share"
data-ga-action="select_collection"
data-ga-label="($('#collections-action-add-to-existing').val() === 'Favorites') ? 'Favorites' : 'non_favorites_collection'">
</select>
<div class="collections-retry-load-on-error usa-input-error-message selection-validation-message">
Unable to load your collection due to an error<br>
<a href="#">Please try again</a>
</div>
</div>
</div>
<div class="action-panel-actions">
<button class="action-panel-submit"
type="submit"
data-loading-label="Adding..."
data-pinger-ignore
data-ga-category="save_share"
data-ga-action="collections"
data-ga-label="add">
Add
</button>
<button class="action-panel-cancel"
aria-label="Close 'Add to Collections' panel"
ref="linksrc=close_collections_panel"
aria-controls="collections-action-panel"
aria-expanded="false"
data-ga-category="save_share"
data-ga-action="collections"
data-ga-label="cancel">
Cancel
</button>
</div>
</form>
</div>
</div>
<div id="bibliography-action-panel"
class="bibliography-action-panel action-panel in-progress-dots-panel"
aria-hidden="true"
data-bibliography-open-panel-enabled="false"
data-bibliography-open-panel-url-hash="#open-bibliography-panel">
<div class="inner-wrap">
<h3 class="action-panel-heading">
Add to My Bibliography
</h3>
<form id="bibliography-action-panel-form"
class="bibliography-action-panel-form action-panel-content action-form action-panel-smaller-selectors"
data-add-to-bibliography-max-amount="100"
data-add-to-bibliography-batch-size="10"
data-bibliography-delegates-url="/list-bibliography-delegates/"
data-add-to-bibliography-url="/add-to-bibliography/"
data-get-article-ids-by-search-url="/get-article-ids-by-search/"
data-mybib-root-url="https://www.ncbi.nlm.nih.gov/myncbi/collections/mybibliography/">
<input type="hidden" name="csrfmiddlewaretoken" value="rflWEJ0KQSqzRd066f1777SfRtZYb5BmI251hzt6qtd3LE6WJyE9BfoTpxHa4G9G">
<div class="action-panel-control-wrap bibliographies-controls">
<div class="choice-group">
<ul class="bibliographies-action-add radio-group-items">
<li>
<input name="bibliography" id="my-bibliography" class="my-bibliography" type="radio" checked/>
<label for="my-bibliography">My Bibliography</label>
</li>
</ul>
</div>
</div>
<div class="bibliographies-retry-load-on-error usa-input-error-message selection-validation-message">
Unable to load your delegates due to an error<br>
<a href="#">Please try again</a>
</div>
<div class="action-panel-actions">
<button class="action-panel-submit"
type="submit"
data-loading-label="Adding..."
data-pinger-ignore>
Add
</button>
<button class="action-panel-cancel"
aria-label="Close 'Add to bibliography' panel"
ref="linksrc=close_bibliography_panel"
aria-controls="bibliography-action-panel"
aria-expanded="false"
data-ga-category="save_share"
data-ga-action="mybib"
data-ga-label="cancel">
Cancel
</button>
</div>
</form>
</div>
</div>
<div id="saved-search-action-panel" class="saved-search-action-panel action-panel " aria-hidden="true"
data-saved-search-open-panel-enabled="false"
data-saved-search-open-panel-url-hash="#open-saved-search-panel">
<div class="inner-wrap">
<h2 class="action-panel-heading">
Your saved search
</h2>
<form id="saved-search-action-panel-form"
class="saved-search-action-panel-form action-panel-content action-form"
data-create-saved-search-url="/create-saved-search/"
data-try-search-terms-url="/try-search-term/"
data-saved-search-root-url="https://www.ncbi.nlm.nih.gov/myncbi/searches/">
<input type="hidden" name="csrfmiddlewaretoken" value="rflWEJ0KQSqzRd066f1777SfRtZYb5BmI251hzt6qtd3LE6WJyE9BfoTpxHa4G9G">
<div class="action-panel-control-wrap">
<label for="saved-search-name" class="action-panel-label saved-search-name-label required-field-asterisk">
Name of saved search:
</label>
<input maxlength="200"
type="text"
name="saved-search-name"
id="saved-search-name"
class="saved-search-name"
value=""
required
pattern="[^&quot;&amp;=&lt;&gt;\/]*" title="The following characters are not allowed in the Name field: &quot;&amp;=&lt;&gt;/">
</div>
<div class="action-panel-control-wrap">
<label for="saved-search-term" class="action-panel-label required-field-asterisk">
Search terms:
</label>
<textarea name="saved-search-term" id="saved-search-term" class="saved-search-term" required></textarea>
</div>
<div class="test-search-term-wrap">
<a href="#" class="try-search-term">Test search terms</a>
</div>
<div class="choice-group action-panel-extra-margin-top">
<span class="action-panel-label" id="fieldset-label">
Would you like email updates of new search results?
</span>
<fieldset id="saved-search-alert" aria-describedby="fieldset-label">
<legend class="usa-sr-only">Saved Search Alert Radio Buttons</legend>
<ul class="radio-group-items">
<li>
<input type="radio" id="saved-search-alert-yes" class="saved-search-alert-yes" name="saved-search-alert" value="yes" checked>
<label for="saved-search-alert-yes" class="action-panel-label">Yes</label>
</li>
<li>
<input aria-label="No radio input" type="radio" id="saved-search-alert-no" class="saved-search-alert-no" name="saved-search-alert" value="no">
<label for="saved-search-alert-no" class="action-panel-label">No</label>
</li>
</ul>
</fieldset>
</div>
<div class="alert-schedule-wrap">
<div class="action-panel-control-wrap">
<label class="action-panel-label">
Email:
</label>
<span aria-label="Email address" id="saved-search-email" class="action-panel-label"><span class="action-panel-label-bold"></span> (<a class="myncbi-account-settings" href="https://www.ncbi.nlm.nih.gov/account/settings/">change</a>)</span>
</div>
<div class="action-panel-control-wrap action-panel-extra-margin-top">
<label for="saved-search-frequency" class="action-panel-label">
Frequency:
</label>
<select id="saved-search-frequency" class="no-border-panel-selector saved-search-frequency">
<option value="monthly">Monthly</option>
<option value="weekly">Weekly</option>
<option value="daily">Daily</option>
</select>
</div>
<div class="action-panel-control-wrap saved-search-monthly-additional">
<label for="saved-search-monthly-on-day" class="action-panel-label">
Which day?
</label>
<select id="saved-search-monthly-on-day" class="no-border-panel-selector">
<option value="Sunday">The first Sunday</option>
<option value="Monday">The first Monday</option>
<option value="Tuesday">The first Tuesday</option>
<option value="Wednesday">The first Wednesday</option>
<option value="Thursday">The first Thursday</option>
<option value="Friday">The first Friday</option>
<option value="Saturday">The first Saturday</option>
<option value="day">The first day</option>
<option value="weekday">The first weekday</option>
</select>
</div>
<div class="action-panel-control-wrap saved-search-weekly-additional">
<label for="saved-search-weekly-on-day" class="action-panel-label">
Which day?
</label>
<select id="saved-search-weekly-on-day" class="no-border-panel-selector saved-search-weekly-on-day">
<option value="Sunday">Sunday</option>
<option value="Monday">Monday</option>
<option value="Tuesday">Tuesday</option>
<option value="Wednesday">Wednesday</option>
<option value="Thursday">Thursday</option>
<option value="Friday">Friday</option>
<option value="Saturday">Saturday</option>
</select>
</div>
<div class="action-panel-control-wrap">
<label for="saved-search-report" class="action-panel-label">
Report format:
</label>
<select id="saved-search-report" class="no-border-panel-selector saved-search-report">
<option value="DocSum">Summary</option>
<option value="DocSumText">Summary (text)</option>
<option value="Abstract">Abstract</option>
<option value="AbstractText">Abstract (text)</option>
<option value="MEDLINE">PubMed</option>
</select>
</div>
<div class="action-panel-control-wrap">
<label for="saved-search-amount" class="action-panel-label">
Send at most:
</label>
<select id="saved-search-amount" class="no-border-panel-selector saved-search-amount">
<option value="1">1 item</option>
<option value="5" selected>5 items</option>
<option value="10">10 items</option>
<option value="20">20 items</option>
<option value="50">50 items</option>
<option value="100">100 items</option>
<option value="200">200 items</option>
</select>
</div>
<div>
<input type="checkbox" id="saved-search-send-if-no-result" class="saved-search-send-if-no-result" name="saved-search-send-if-no-result">
<label for="saved-search-send-if-no-result" class="action-panel-label smaller-checkbox">
Send even when there aren't any new results
</label>
</div>
<div class="action-panel-control-wrap option-text-in-email-wrap">
<label for="saved-search-email-text" class="action-panel-label">
Optional text in email:
</label>
<textarea name="saved-search-email-text"
id="saved-search-email-text"
class="saved-search-email-text"></textarea>
</div>
</div>
<div class="action-panel-actions">
<button class="action-panel-submit"
type="submit"
data-loading-label="Saving..."
data-ga-category="save_share"
data-ga-action="alert"
data-ga-label="save">
Save
</button>
<button class="action-panel-cancel"
aria-label="Close 'Your saved search' panel"
ref="linksrc=close_saved_search_panel"
aria-controls="saved-search-action-panel"
aria-expanded="false"
data-ga-category="save_share"
data-ga-action="alert"
data-ga-label="cancel">
Cancel
</button>
</div>
</form>
</div>
</div>
<div id="citation-manager-action-panel" class="citation-manager-action-panel action-panel" aria-hidden="true">
<div class="inner-wrap">
<h2 class="action-panel-heading">
Create a file for external citation management software
</h2>
<form id="citation-manager-action-panel-form"
class="action-panel-content action-form"
action="/results-export-ids/"
data-by-search-action="/results-export-search-data/"
data-by-ids-action="/results-export-ids/"
method="post"
data-by-search-method="post"
data-by-ids-method="post">
<input type="hidden" name="csrfmiddlewaretoken" value="rflWEJ0KQSqzRd066f1777SfRtZYb5BmI251hzt6qtd3LE6WJyE9BfoTpxHa4G9G">
<input name="results-format" type="hidden" value="pubmed"/>
<div class="action-panel-actions">
<button class="action-panel-submit"
type="submit"
data-loading-label="Sending..."
data-ga-category="save_share"
data-ga-action="citation_manager"
data-ga-label="save">
Create file
</button>
<button class="action-panel-cancel"
aria-label="Close 'Send citations to citation manager' panel"
ref="linksrc=close_citation_manager_panel"
aria-controls="citation-manager-action-panel"
aria-expanded="false"
data-ga-category="save_share"
data-ga-action="citation_manager"
data-ga-label="cancel">
Cancel
</button>
</div>
</form>
</div>
</div>
<div id="rss-action-panel" class="rss-action-panel action-panel " aria-hidden="true">
<div class="inner-wrap">
<h2 class="action-panel-heading">
Your RSS Feed
</h2>
<form id="rss-action-panel-form"
class="rss-action-panel-form action-panel-content action-form"
data-create-rss-feed-url="/create-rss-feed-url/"
data-search-form-term-value="">
<input type="hidden" name="csrfmiddlewaretoken" value="rflWEJ0KQSqzRd066f1777SfRtZYb5BmI251hzt6qtd3LE6WJyE9BfoTpxHa4G9G">
<div class="action-panel-control-wrap">
<label for="rss-name" class="action-panel-label required-field-asterisk">
Name of RSS Feed:
</label>
<input maxlength="200"
placeholder="Name"
type="text"
name="rss-name"
id="rss-name"
class="rss-name"
value=''
required
pattern="[^&quot;&amp;=&lt;&gt;\/]*" title="The following characters are not allowed in the Name field: &quot;&amp;=&lt;&gt;/">
</div>
<div class="rss-limit-wrap">
<div class="action-panel-control-wrap action-panel-extra-margin-top">
<label for="rss-limit" class="action-panel-label">
Number of items displayed:
</label>
<select id="rss-limit" class="no-border-panel-selector rss-limit">
<option value="5">5</option>
<option value="10">10</option>
<option value="15" selected="selected">15</option>
<option value="20">20</option>
<option value="50">50</option>
<option value="100">100</option>
</select>
</div>
</div>
<div class="action-panel-actions">
<button class="action-panel-submit"
type="submit"
data-loading-label="Creating..."
data-ga-category="save_share"
data-ga-action="alert"
data-ga-label="save">
Create RSS
</button>
<button class="action-panel-cancel"
aria-label="Close 'Your RSS' panel"
ref="linksrc=close_rss_panel"
aria-controls="rss-action-panel"
aria-expanded="false"
data-ga-category="save_share"
data-ga-action="alert"
data-ga-label="cancel">
Cancel
</button>
</div>
<div class="action-panel-control-wrap rss-link-copy-wrap">
<label for="rss-link" class="usa-sr-only">RSS Link</label>
<input placeholder="Your RSS Feed Link" type="text" name="rss-link" id="rss-link" class="rss-link" title="RSS Link">
<button
type="button"
disabled
class="rss-link-copy-button disabled"
data-ga-category="save_share"
data-ga-action="rss"
data-ga-label="copy">
Copy
</button>
</div>
</form>
</div>
</div>
</div>
</div>
<div class="article-page" id="article-page" data-article-pmid="22550198">
<aside class="page-sidebar">
<div class="inner-wrap">
<div class="full-text-links">
<div class="full-view">
<h3 class="title">
Full text links
</h3>
<div class="full-text-links-list">
<a class="link-item
dialog-focus"
href="https://jamanetwork.com/journals/jama/fullarticle/10.1001/jama.2012.3424"
target="_blank"
rel="noopener"
ref="linksrc=fulltextorjournal_fulltext&amp;is_pmc=False&amp;PrId=7898&amp;itool=Abstract-def&amp;log$=linkouticon&amp;uid=22550198&amp;db=pubmed&amp;nlmid=7501160"
title="See full text options at Silverchair Information Systems"
data-ga-category="full_text"
data-ga-action="Silverchair Information Systems"
data-ga-label="22550198"
><img src="https://cdn.ncbi.nlm.nih.gov/corehtml/query/egifs/https:--jama.jamanetwork.com-images-PUBMED_JAMA_full.gif" alt="Silverchair Information Systems full text link"><span class="text">
Silverchair Information Systems
</span></a>
</div>
</div>
<div class="short-view">
<a href="#" class="full-text-links-button full-text-links-dialog-trigger">
Full text links
</a>
</div>
</div>
<div class="actions-buttons sidebar"><h3 class="title">Actions</h3><div class="inner-wrap"><button class="citation-button citation-dialog-trigger"
aria-label="Open dialog with citation text in different styles"
data-ga-category="save_share"
data-ga-action="cite"
data-ga-label="open"
data-all-citations-url="/22550198/citations/"
data-citation-style="nlm"
data-pubmed-format-link="/22550198/export/"><span class="button-label">Cite</span></button><link type="text/css" href="ncbi-overlay-block/src/overlay-block.css"><div class="collections-button-container" data-article-id="22550198" data-article-db="pubmed"><button class="collections-button collections-dialog-trigger"
aria-label="Save article in MyNCBI collections."
data-ga-category="collections_button"
data-ga-action="click"
data-ga-label="collections_button"
data-collections-open-dialog-enabled="false"
data-collections-open-dialog-url="https://account.ncbi.nlm.nih.gov/?back_url=https%3A%2F%2Fpubmed.ncbi.nlm.nih.gov%2F22550198%2F%23open-collections-dialog"
data-in-collections="false"><span class="button-label">Collections</span></button><div class="overlay" role="dialog"><div id="collections-action-dialog"
class="dialog collections-dialog"
aria-hidden="true"><div class="title">Add to Collections</div><div class="collections-action-panel action-panel"><form id="collections-action-dialog-form"
class="collections-action-panel-form action-panel-content action-form action-panel-smaller-selectors"
data-existing-collections-url="/list-existing-collections/"
data-add-to-existing-collection-url="/add-to-existing-collection/"
data-create-and-add-to-new-collection-url="/create-and-add-to-new-collection/"
data-myncbi-max-collection-name-length="100"
data-collections-root-url="https://www.ncbi.nlm.nih.gov/myncbi/collections/"><input type="hidden" name="csrfmiddlewaretoken" value="rflWEJ0KQSqzRd066f1777SfRtZYb5BmI251hzt6qtd3LE6WJyE9BfoTpxHa4G9G"><div class="choice-group" role="radiogroup"><ul class="radio-group-items"><li><input type="radio"
id="collections-action-dialog-new"
class="collections-new"
name="collections"
value="new"
data-ga-category="collections_button"
data-ga-action="click"
data-ga-label="collections_radio_new"><label for="collections-action-dialog-new">Create a new collection</label></li><li><input type="radio"
id="collections-action-dialog-existing"
class="collections-existing"
name="collections"
value="existing"
checked="true"
data-ga-category="collections_button"
data-ga-action="click"
data-ga-label="collections_radio_existing"><label for="collections-action-dialog-existing">Add to an existing collection</label></li></ul></div><div class="controls-wrapper"><div class="action-panel-control-wrap new-collections-controls"><label for="collections-action-dialog-add-to-new" class="action-panel-label required-field-asterisk">
Name your collection:
</label><input
type="text"
name="add-to-new-collection"
id="collections-action-dialog-add-to-new"
class="collections-action-add-to-new"
pattern="[^&quot;&amp;=&lt;&gt;\/]*" title="The following characters are not allowed in the Name field: &quot;&amp;=&lt;&gt;/"
maxlength="100"
data-ga-category="collections_button"
data-ga-action="create_collection"
data-ga-label="non_favorties_collection"><div class="collections-new-name-too-long usa-input-error-message selection-validation-message">
Name must be less than 100 characters
</div></div><div class="action-panel-control-wrap existing-collections-controls"><label for="collections-action-dialog-add-to-existing" class="action-panel-label">
Choose a collection:
</label><select id="collections-action-dialog-add-to-existing"
class="action-panel-selector collections-action-add-to-existing"
data-ga-category="collections_button"
data-ga-action="select_collection"
data-ga-label="($('.collections-action-add-to-existing').val() === 'Favorites') ? 'Favorites' : 'non_favorites_collection'"></select><div class="collections-retry-load-on-error usa-input-error-message selection-validation-message">
Unable to load your collection due to an error<br><a href="#">Please try again</a></div></div></div><div class="action-panel-actions"><button class="action-panel-submit"
type="submit"
data-loading-label="Adding..."
data-pinger-ignore
data-ga-category="collections_button"
data-ga-action="click"
data-ga-label="add">
Add
</button><button class="action-panel-cancel"
aria-label="Close 'Add to Collections' panel"
ref="linksrc=close_collections_panel"
aria-controls="collections-action-panel"
aria-expanded="false"
data-ga-category="collections_button"
data-ga-action="click"
data-ga-label="cancel">
Cancel
</button></div></form></div></div></div></div><button class="more-actions-button more-actions-dialog-trigger"
title="Open dialog with more actions to take"
ref="linksrc=more_actions_btn"></button><div class="display-options" data-format-key="format"
data-default-format-value="abstract"
data-current-format-value="abstract" role="region"><button
class="trigger usa-button"
title="Change format"
data-ga-category="display_options"
data-ga-action="display_options_dialog"><span class="button-label">Display options</span></button><div class="dropdown" hidden><div class="title">
Display options
</div><div class="content"><div class="format-container"><span class="option-label">
Format
</span><select name="format" data-initial-value="abstract" aria-label="Display format" id="sidebar-actions-display-format"><option value="abstract">Abstract</option><option value="pubmed">PubMed</option><option value="pmid">PMID</option></select></div></div></div></div></div></div>
<div class="social-sharing">
<h3 class="title">
Share
</h3>
<ul class="social-sharing-links usa-unstyled-list">
<li>
<a href="http://twitter.com/intent/tweet?text=Characteristics%20of%20clinical%20trials%20registered%20in%20ClinicalTrials.gov%2C%202007-2010%20https%3A//pubmed.ncbi.nlm.nih.gov/22550198/"
class="share-link share-link-twitter"
rel="noreferrer noopener"
target="Pubmed-Social-Media-Share-Popup"
title="Share article on Twitter"
data-ga-category="save_share"
data-ga-action="social"
data-ga-label="twitter"></a>
</li>
<li>
<a href="http://www.facebook.com/sharer/sharer.php?u=https%3A//pubmed.ncbi.nlm.nih.gov/22550198/"
class="share-link share-link-facebook"
rel="noreferrer noopener"
target="Pubmed-Social-Media-Share-Popup"
title="Share article on Facebook"
data-ga-category="save_share"
data-ga-action="social"
data-ga-label="fb"></a>
</li>
<li>
<div class="share-permalink">
<button class="trigger"
title="Show article permalink"
ref="linksrc=show_permalink_btn">
</button>
<div class="dropdown" hidden>
<div class="title">
Permalink
</div>
<div class="content">
<input type="text"
class="permalink-text"
value="https://pubmed.ncbi.nlm.nih.gov/22550198/"
aria-label="Article permalink"/><button class="permalink-copy-button usa-button-primary"
title="Copy article permalink"
data-ga-category="save_share"
data-ga-action="link"
data-ga-label="copy_link"><span class="button-title">Copy</span></button>
</div>
</div>
</div>
</li>
</ul>
</div>
<nav class="page-navigator" role="navigation" aria-label="Page navigation">
<div class="full-view">
<h3 class="title">
Page navigation
</h3>
<ul class="items-list">
<li class="heading ">
<a href="#heading"
aria-label="navigate to Title &amp; authors section"
data-ga-category="page_nav"
data-ga-action="heading">
Title &amp; authors
</a>
</li>
<li class="abstract ">
<a href="#abstract"
aria-label="navigate to Abstract section"
data-ga-category="page_nav"
data-ga-action="abstract">
Abstract
</a>
</li>
<li class="linked-commentary current">
<a href="#linked-commentary"
aria-label="navigate to Comment in section"
data-ga-category="page_nav"
data-ga-action="linked-commentary">
Comment in
</a>
</li>
<li class="similar ">
<a href="#similar"
aria-label="navigate to Similar articles section"
data-ga-category="page_nav"
data-ga-action="similar">
Similar articles
</a>
</li>
<li class="citedby ">
<a href="#citedby"
aria-label="navigate to Cited by section"
data-ga-category="page_nav"
data-ga-action="citedby">
Cited by
</a>
</li>
<li class="publication-types ">
<a href="#publication-types"
aria-label="navigate to Publication types section"
data-ga-category="page_nav"
data-ga-action="publication-types">
Publication types
</a>
</li>
<li class="mesh-terms ">
<a href="#mesh-terms"
aria-label="navigate to MeSH terms section"
data-ga-category="page_nav"
data-ga-action="mesh-terms">
MeSH terms
</a>
</li>
<li class="related-links ">
<a href="#related-links"
aria-label="navigate to Related information section"
data-ga-category="page_nav"
data-ga-action="related-links">
Related information
</a>
</li>
<li class="grants ">
<a href="#grants"
aria-label="navigate to Grants and funding section"
data-ga-category="page_nav"
data-ga-action="grants">
Grants and funding
</a>
</li>
<li class="linkout ">
<a href="#linkout"
aria-label="navigate to LinkOut - more resources section"
data-ga-category="page_nav"
data-ga-action="linkout">
LinkOut - more resources
</a>
</li>
</ul>
</div>
<select class="short-view" autocomplete="off" title="navigate to selected section" aria-label="Navigate to page section">
<option value="heading">Title &amp; authors</option>
<option value="abstract">Abstract</option>
<option value="linked-commentary">Comment in</option>
<option value="similar">Similar articles</option>
<option value="citedby">Cited by</option>
<option value="publication-types">Publication types</option>
<option value="mesh-terms">MeSH terms</option>
<option value="related-links">Related information</option>
<option value="grants">Grants and funding</option>
<option value="linkout">LinkOut - more resources</option>
</select>
</nav>
</div>
</aside>
<main class="article-details" id="article-details">
<!-- "Filters applied" shows only when page is redirected from search -->
<!-- because search found one result -->
<header class="heading" id="heading">
<div class="full-view" id="full-view-heading">
<div class="article-citation">
<div class="article-source">
<div class="journal-actions dropdown-block"><button id="full-view-journal-trigger"
class="journal-actions-trigger trigger"
ref="linksrc=journal_actions_btn"
title="JAMA"
tabindex="0"
aria-controls="full-view-journal"
aria-expanded="false"
aria-label="Toggle dropdown menu for journal JAMA"
data-pinger-ignore>
JAMA
</button><div id="full-view-journal"
class="journal-actions-dropdown dropdown dropdown-container"
hidden
aria-label="Dropdown menu for journal JAMA"><div class="title">Actions</div><div class="content"><ul class="journal-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link"
href="/?term=%22JAMA%22%5Bjour%5D&amp;sort=date&amp;sort_order=desc"
data-href="/?term=%22JAMA%22%5Bjour%5D&amp;sort=date&amp;sort_order=desc"
ref="linksrc=search_in_pubmed_journal_name_link&amp;journal_abbrev=JAMA"
data-ga-category="search"
data-ga-action="journal_link"
data-ga-label="JAMA">
Search in PubMed
</a></li><li><a class="search-in-nlm-catalog-link dropdown-block-link"
ref ="linksrc=search_in_nlm_catalog_link"
href="https://www.ncbi.nlm.nih.gov/nlmcatalog?term=%22JAMA%22%5BTitle+Abbreviation%5D"
data-ga-category="search_catalog"
data-ga-action="journal_link"
data-ga-label="JAMA">
Search in NLM Catalog
</a></li><li><a class="add-to-search-link dropdown-block-link"
ref ="linksrc=add_to_search_link"
role="button"
data-search-term='"JAMA"[jour]'
data-ga-category="search"
data-ga-action="add_to_search"
data-ga-label='"JAMA"[jour]'
href="#">
Add to Search
</a></li></ul></div></div></div><span class="period">. </span><span class="cit">2012 May 2;307(17):1838-47.</span>
</div>
<span class="citation-doi">
doi: 10.1001/jama.2012.3424.
</span>
</div>
<h1 class="heading-title">
Characteristics of clinical trials registered in ClinicalTrials.gov, 2007-2010
</h1>
<div class="inline-authors">
<div class="authors">
<div class="authors-list">
<span class="authors-list-item "><a class="full-name"
href="/?term=Califf+RM&amp;cauthor_id=22550198"
ref="linksrc=author_name_link"
data-ga-category="search"
data-ga-action="author_link"
data-ga-label="Robert M Califf">Robert M Califf</a><sup class="affiliation-links"><span class="author-sup-separator">&nbsp;</span><a class="affiliation-link" title="Duke Translational Medicine Institute, 200 Trent Dr, 1117 Davison Bldg, Durham, NC 27710, USA. robert.califf@duke.edu" href="#full-view-affiliation-1" ref="linksrc=author_aff">
1
</a></sup><span class="comma">,&nbsp;</span></span><span class="authors-list-item "><a class="full-name"
href="/?term=Zarin+DA&amp;cauthor_id=22550198"
ref="linksrc=author_name_link"
data-ga-category="search"
data-ga-action="author_link"
data-ga-label="Deborah A Zarin">Deborah A Zarin</a><span class="comma">,&nbsp;</span></span><span class="authors-list-item "><a class="full-name"
href="/?term=Kramer+JM&amp;cauthor_id=22550198"
ref="linksrc=author_name_link"
data-ga-category="search"
data-ga-action="author_link"
data-ga-label="Judith M Kramer">Judith M Kramer</a><span class="comma">,&nbsp;</span></span><span class="authors-list-item "><a class="full-name"
href="/?term=Sherman+RE&amp;cauthor_id=22550198"
ref="linksrc=author_name_link"
data-ga-category="search"
data-ga-action="author_link"
data-ga-label="Rachel E Sherman">Rachel E Sherman</a><span class="comma">,&nbsp;</span></span><span class="authors-list-item "><a class="full-name"
href="/?term=Aberle+LH&amp;cauthor_id=22550198"
ref="linksrc=author_name_link"
data-ga-category="search"
data-ga-action="author_link"
data-ga-label="Laura H Aberle">Laura H Aberle</a><span class="comma">,&nbsp;</span></span><span class="authors-list-item "><a class="full-name"
href="/?term=Tasneem+A&amp;cauthor_id=22550198"
ref="linksrc=author_name_link"
data-ga-category="search"
data-ga-action="author_link"
data-ga-label="Asba Tasneem">Asba Tasneem</a></span>
</div>
</div>
</div>
<div class="short-article-details">
Affiliations
<button
class="more-details"
id="toggle-authors"
data-alt-text="Collapse"
aria-controls="expanded-authors"
aria-expanded="false"
data-pinger-ignore
data-fetch-url="/22550198/long-authors/"
data-id-prefix="">
<span class="title">
Expand
</span>
</button>
</div>
<div class="extended-article-details" id="expanded-authors" aria-hidden="true">
<div class="expanded-authors" id="full-view-expanded-authors">
<div class="affiliations">
<h3 class="title">
Affiliation
</h3>
<ul class="item-list">
<li data-affiliation-id="full-view-affiliation-1"
id="full-view-affiliation-1"
><sup class="key">1</sup> Duke Translational Medicine Institute, 200 Trent Dr, 1117 Davison Bldg, Durham, NC 27710, USA. robert.califf@duke.edu</li>
</ul>
</div>
</div>
</div>
<ul class="identifiers" id="full-view-identifiers">
<li>
<span class="identifier pubmed">
<span class="id-label">
PMID:
</span>
<strong class="current-id" title="PubMed ID">22550198</strong>
</span>
</li>
<li>
<span class="identifier doi">
<span class="id-label">
DOI:
</span>
<a class="id-link"
target="_blank"
rel="noopener"
ref="linksrc=article_id_link&amp;article_id=10.1001/jama.2012.3424&amp;id_type=DOI"
href="https://doi.org/10.1001/jama.2012.3424"
data-ga-category="full_text"
data-ga-action="DOI"
>
10.1001/jama.2012.3424
</a>
</span>
</li>
</ul>
<div class="in-clipboard-label " hidden>
Item in Clipboard
</div>
</div>
<div class="short-view" id="short-view-heading">
<h1 class="heading-title">
Characteristics of clinical trials registered in ClinicalTrials.gov, 2007-2010
</h1>
<div class="short-citation">
<span class="authors-list">
<span class="authors-list-item "><span class="full-name">Robert M Califf</span><span class="citation-separator">&nbsp;et al.</span></span>
</span>
<span class="citation-journal">
JAMA<span class="citation-separator">.</span>
</span>
<span class="date">
<time class="citation-year" datetime="2012">2012</time><span class="citation-separator">.</span>
</span>
</div>
<div class="more-article-details-section with-display-settings">
<button class="more-article-details"
id="toggle-article-details"
data-alt-text="Hide details"
ref="linksrc=toggle_article_details"
aria-controls="full-article-details"
aria-expanded="false"
data-fetch-url="/22550198/long-authors/"
data-id-prefix="">
<span class="title">Show details</span>
</button>
<div class="display-options" data-format-key="format"
data-default-format-value="abstract"
data-current-format-value="abstract" role="region">
<button
class="trigger usa-button"
title="Change format"
data-ga-category="display_options"
data-ga-action="display_options_dialog">
<span class="button-label">Display options</span>
</button>
<div class="dropdown" hidden>
<div class="title">
Display options
</div>
<div class="content">
<div class="format-container">
<span class="option-label">
Format
</span>
<select name="format" data-initial-value="abstract" aria-label="Display format" id="mobile-display-format">
<option value="abstract">Abstract</option>
<option value="pubmed">PubMed</option>
<option value="pmid">PMID</option>
</select>
</div>
</div>
</div>
</div>
</div>
<div class="extended-article-details" id="full-article-details" aria-hidden="true">
<div class="article-citation">
<div class="article-source">
<div class="journal-actions dropdown-block"><button id="short-view-journal-trigger"
class="journal-actions-trigger trigger"
ref="linksrc=journal_actions_btn"
title="JAMA"
tabindex="0"
aria-controls="short-view-journal"
aria-expanded="false"
aria-label="Toggle dropdown menu for journal JAMA"
data-pinger-ignore>
JAMA
</button><div id="short-view-journal"
class="journal-actions-dropdown dropdown dropdown-container"
hidden
aria-label="Dropdown menu for journal JAMA"><div class="title">Actions</div><div class="content"><ul class="journal-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link"
href="/?term=%22JAMA%22%5Bjour%5D&amp;sort=date&amp;sort_order=desc"
data-href="/?term=%22JAMA%22%5Bjour%5D&amp;sort=date&amp;sort_order=desc"
ref="linksrc=search_in_pubmed_journal_name_link&amp;journal_abbrev=JAMA"
data-ga-category="search"
data-ga-action="journal_link"
data-ga-label="JAMA">
Search in PubMed
</a></li><li><a class="search-in-nlm-catalog-link dropdown-block-link"
ref ="linksrc=search_in_nlm_catalog_link"
href="https://www.ncbi.nlm.nih.gov/nlmcatalog?term=%22JAMA%22%5BTitle+Abbreviation%5D"
data-ga-category="search_catalog"
data-ga-action="journal_link"
data-ga-label="JAMA">
Search in NLM Catalog
</a></li><li><a class="add-to-search-link dropdown-block-link"
ref ="linksrc=add_to_search_link"
role="button"
data-search-term='"JAMA"[jour]'
data-ga-category="search"
data-ga-action="add_to_search"
data-ga-label='"JAMA"[jour]'
href="#">
Add to Search
</a></li></ul></div></div></div><span class="period">. </span><span class="cit">2012 May 2;307(17):1838-47.</span>
</div>
<span class="citation-doi">
doi: 10.1001/jama.2012.3424.
</span>
</div>
<div class="expanded-authors" id="short-view-expanded-authors">
<div class="authors">
<h3 class="title">
Authors
</h3>
<div class="authors-list">
<span class="authors-list-item "><a class="full-name"
href="/?term=Califf+RM&amp;cauthor_id=22550198"
ref="linksrc=author_name_link"
data-ga-category="search"
data-ga-action="author_link"
data-ga-label="Robert M Califf">Robert M Califf</a><sup class="affiliation-links"><span class="author-sup-separator">&nbsp;</span><a class="affiliation-link" title="Duke Translational Medicine Institute, 200 Trent Dr, 1117 Davison Bldg, Durham, NC 27710, USA. robert.califf@duke.edu" href="#short-view-affiliation-1" ref="linksrc=author_aff">
1
</a></sup><span class="comma">,&nbsp;</span></span><span class="authors-list-item "><a class="full-name"
href="/?term=Zarin+DA&amp;cauthor_id=22550198"
ref="linksrc=author_name_link"
data-ga-category="search"
data-ga-action="author_link"
data-ga-label="Deborah A Zarin">Deborah A Zarin</a><span class="comma">,&nbsp;</span></span><span class="authors-list-item "><a class="full-name"
href="/?term=Kramer+JM&amp;cauthor_id=22550198"
ref="linksrc=author_name_link"
data-ga-category="search"
data-ga-action="author_link"
data-ga-label="Judith M Kramer">Judith M Kramer</a><span class="comma">,&nbsp;</span></span><span class="authors-list-item "><a class="full-name"
href="/?term=Sherman+RE&amp;cauthor_id=22550198"
ref="linksrc=author_name_link"
data-ga-category="search"
data-ga-action="author_link"
data-ga-label="Rachel E Sherman">Rachel E Sherman</a><span class="comma">,&nbsp;</span></span><span class="authors-list-item "><a class="full-name"
href="/?term=Aberle+LH&amp;cauthor_id=22550198"
ref="linksrc=author_name_link"
data-ga-category="search"
data-ga-action="author_link"
data-ga-label="Laura H Aberle">Laura H Aberle</a><span class="comma">,&nbsp;</span></span><span class="authors-list-item "><a class="full-name"
href="/?term=Tasneem+A&amp;cauthor_id=22550198"
ref="linksrc=author_name_link"
data-ga-category="search"
data-ga-action="author_link"
data-ga-label="Asba Tasneem">Asba Tasneem</a></span>
</div>
</div>
<div class="affiliations">
<h3 class="title">
Affiliation
</h3>
<ul class="item-list">
<li data-affiliation-id="short-view-affiliation-1"
id="short-view-affiliation-1"
><sup class="key">1</sup> Duke Translational Medicine Institute, 200 Trent Dr, 1117 Davison Bldg, Durham, NC 27710, USA. robert.califf@duke.edu</li>
</ul>
</div>
</div>
<ul class="identifiers" id="short-view-identifiers">
<li>
<span class="identifier pubmed">
<span class="id-label">
PMID:
</span>
<strong class="current-id" title="PubMed ID">22550198</strong>
</span>
</li>
<li>
<span class="identifier doi">
<span class="id-label">
DOI:
</span>
<a class="id-link"
target="_blank"
rel="noopener"
ref="linksrc=article_id_link&amp;article_id=10.1001/jama.2012.3424&amp;id_type=DOI"
href="https://doi.org/10.1001/jama.2012.3424"
data-ga-category="full_text"
data-ga-action="DOI"
>
10.1001/jama.2012.3424
</a>
</span>
</li>
</ul>
<div class="in-clipboard-label " hidden>
Item in Clipboard
</div>
</div>
</div>
</header>
<div class="actions-buttons inline"><div class="inner-wrap"><button class="full-text-links-button full-text-links-dialog-trigger"
title="Open dialog with full text links"
ref="linksrc=full_text_links">
Full text links
</button><button class="citation-button citation-dialog-trigger"
aria-label="Open dialog with citation text in different styles"
data-ga-category="save_share"
data-ga-action="cite"
data-ga-label="open"
data-all-citations-url="/22550198/citations/"
data-citation-style="nlm"
data-pubmed-format-link="/22550198/export/"><span class="button-label">Cite</span></button><button class="more-actions-button more-actions-dialog-trigger"
title="Open dialog with more actions to take"
ref="linksrc=more_actions_btn"></button><div class="display-options" data-format-key="format"
data-default-format-value="abstract"
data-current-format-value="abstract" role="region"><button
class="trigger usa-button"
title="Change format"
data-ga-category="display_options"
data-ga-action="display_options_dialog"><span class="button-label">Display options</span></button><div class="dropdown" hidden><div class="title">
Display options
</div><div class="content"><div class="format-container"><span class="option-label">
Format
</span><select name="format" data-initial-value="abstract" aria-label="Display format" id="inline-actions-display-format"><option value="abstract">Abstract</option><option value="pubmed">PubMed</option><option value="pmid">PMID</option></select></div></div></div></div></div></div>
<div class="abstract" id="abstract">
<h2 class="title">
Abstract
</h2>
<div class="abstract-content selected"
id="eng-abstract">
<p>
<strong class="sub-title">
Context:
</strong>
Recent reports highlight gaps between guidelines-based treatment recommendations and evidence from clinical trials that supports those recommendations. Strengthened reporting requirements for studies registered with ClinicalTrials.gov enable a comprehensive evaluation of the national trials portfolio.
</p>
<p>
<strong class="sub-title">
Objective:
</strong>
To examine fundamental characteristics of interventional clinical trials registered in the ClinicalTrials.gov database.
</p>
<p>
<strong class="sub-title">
Methods:
</strong>
A data set comprising 96,346 clinical studies from ClinicalTrials.gov was downloaded on September 27, 2010, and entered into a relational database to analyze aggregate data. Interventional trials were identified and analyses were focused on 3 clinical specialties-cardiovascular, mental health, and oncology-that together encompass the largest number of disability-adjusted life-years lost in the United States.
</p>
<p>
<strong class="sub-title">
Main outcome measures:
</strong>
Characteristics of registered clinical trials as reported data elements in the trial registry; how those characteristics have changed over time; differences in characteristics as a function of clinical specialty; and factors associated with use of randomization, blinding, and data monitoring committees (DMCs).
</p>
<p>
<strong class="sub-title">
Results:
</strong>
The number of registered interventional clinical trials increased from 28,881 (October 2004-September 2007) to 40,970 (October 2007-September 2010), and the number of missing data elements has generally declined. Most interventional trials registered between 2007 and 2010 were small, with 62% enrolling 100 or fewer participants. Many clinical trials were single-center (66%; 24,788/37,520) and funded by organizations other than industry or the National Institutes of Health (NIH) (47%; 17,592/37,520). Heterogeneity in the reported methods by clinical specialty; sponsor type; and the reported use of DMCs, randomization, and blinding was evident. For example, reported use of DMCs was less common in industry-sponsored vs NIH-sponsored trials (adjusted odds ratio [OR], 0.11; 95% CI, 0.09-0.14), earlier-phase vs phase 3 trials (adjusted OR, 0.83; 95% CI, 0.76-0.91), and mental health trials vs those in the other 2 specialties. In similar comparisons, randomization and blinding were less frequently reported in earlier-phase, oncology, and device trials.
</p>
<p>
<strong class="sub-title">
Conclusion:
</strong>
Clinical trials registered in ClinicalTrials.gov are dominated by small trials and contain significant heterogeneity in methodological approaches, including reported use of randomization, blinding, and DMCs.
</p>
</div>
</div>
<p class="disclaimer" id="disclaimer">
<a href="/disclaimer/" target="_blank" data-ga-category="literature_resources"
data-ga-action="disclaimer_link" data-ga-label="under_abstract">PubMed Disclaimer</a>
</p>
<div class="linked-articles" id="linked-commentary">
<h2 class="title">
Comment in
</h2>
<ul class="item-list usa-unstyled-list">
<li class="full-docsum">
<div class="docsum-content" style="display:inline;">
<a class="docsum-title"
href="/22550202/"
ref="article_id=22550202&amp;linksrc=comments_link"
data-ga-category="comment_correction"
data-ga-action="abstract_page_link"
data-ga-label="linked-commentary">
The evolution of trial registries and their use to assess the clinical trial enterprise.
</a>
<div class="docsum-citation full-citation">
<span class="docsum-authors full-authors">Dickersin K, Rennie D.</span>
<span class="docsum-authors short-authors">Dickersin K, et al.</span>
<span class="docsum-journal-citation full-journal-citation">JAMA. 2012 May 2;307(17):1861-4. doi: 10.1001/jama.2012.4230.</span>
<span class="docsum-journal-citation short-journal-citation">JAMA. 2012.</span>
<span class="citation-part">PMID: <span class="docsum-pmid">22550202</span></span>
<span class="no-abstract spaced-citation-item citation-part">No abstract available.</span>
</div>
</div>
</li>
</ul>
</div>
<div class="similar-articles" id="similar">
<h2 class="title">
Similar articles
</h2>
<ul class="articles-list" id="similar-articles-list">
<li class="full-docsum">
<div class="docsum-content" style="display:inline;">
<a class="docsum-title"
href="/32845329/"
ref="article_id=32845329&amp;linksrc=similar_articles_link&amp;ordinalpos=1"
data-ga-category="similar_article"
data-ga-action="32845329"
data-ga-label="">
Assessment of Trends in the Design, Accrual, and Completion of Trials Registered in ClinicalTrials.gov by Sponsor Type, 2000-2019.
</a>
<div class="docsum-citation full-citation">
<span class="docsum-authors full-authors">Gresham G, Meinert JL, Gresham AG, Meinert CL.</span>
<span class="docsum-authors short-authors">Gresham G, et al.</span>
<span class="docsum-journal-citation full-journal-citation">JAMA Netw Open. 2020 Aug 3;3(8):e2014682. doi: 10.1001/jamanetworkopen.2020.14682.</span>
<span class="docsum-journal-citation short-journal-citation">JAMA Netw Open. 2020.</span>
<span class="citation-part">PMID: <span class="docsum-pmid">32845329</span></span>
<span class="free-resources spaced-citation-item citation-part">Free PMC article.</span>
</div>
</div>
</li>
<li class="full-docsum">
<div class="docsum-content" style="display:inline;">
<a class="docsum-title"
href="/25439209/"
ref="article_id=25439209&amp;linksrc=similar_articles_link&amp;ordinalpos=2"
data-ga-category="similar_article"
data-ga-action="25439209"
data-ga-label="">
Overview of registered studies in orthodontics: Evaluation of the ClinicalTrials.gov registry.
</a>
<div class="docsum-citation full-citation">
<span class="docsum-authors full-authors">Allareddy V, Rampa S, Masoud MI, Lee MK, Nalliah R, Allareddy V.</span>
<span class="docsum-authors short-authors">Allareddy V, et al.</span>
<span class="docsum-journal-citation full-journal-citation">Am J Orthod Dentofacial Orthop. 2014 Nov;146(5):587-93. doi: 10.1016/j.ajodo.2014.07.019. Epub 2014 Oct 28.</span>
<span class="docsum-journal-citation short-journal-citation">Am J Orthod Dentofacial Orthop. 2014.</span>
<span class="citation-part">PMID: <span class="docsum-pmid">25439209</span></span>
</div>
</div>
</li>
<li class="full-docsum">
<div class="docsum-content" style="display:inline;">
<a class="docsum-title"
href="/24890544/"
ref="article_id=24890544&amp;linksrc=similar_articles_link&amp;ordinalpos=3"
data-ga-category="similar_article"
data-ga-action="24890544"
data-ga-label="">
Characteristics of pediatric cardiovascular clinical trials registered on ClinicalTrials.gov.
</a>
<div class="docsum-citation full-citation">
<span class="docsum-authors full-authors">Hill KD, Chiswell K, Califf RM, Pearson G, Li JS.</span>
<span class="docsum-authors short-authors">Hill KD, et al.</span>
<span class="docsum-journal-citation full-journal-citation">Am Heart J. 2014 Jun;167(6):921-9.e2. doi: 10.1016/j.ahj.2014.02.002. Epub 2014 Feb 17.</span>
<span class="docsum-journal-citation short-journal-citation">Am Heart J. 2014.</span>
<span class="citation-part">PMID: <span class="docsum-pmid">24890544</span></span>
<span class="free-resources spaced-citation-item citation-part">Free PMC article.</span>
</div>
</div>
</li>
<li class="full-docsum">
<div class="docsum-content" style="display:inline;">
<a class="docsum-title"
href="/27881517/"
ref="article_id=27881517&amp;linksrc=similar_articles_link&amp;ordinalpos=4"
data-ga-category="similar_article"
data-ga-action="27881517"
data-ga-label="">
Overview of phase IV clinical trials for postmarket drug safety surveillance: a status report from the ClinicalTrials.gov registry.
</a>
<div class="docsum-citation full-citation">
<span class="docsum-authors full-authors">Zhang X, Zhang Y, Ye X, Guo X, Zhang T, He J.</span>
<span class="docsum-authors short-authors">Zhang X, et al.</span>
<span class="docsum-journal-citation full-journal-citation">BMJ Open. 2016 Nov 23;6(11):e010643. doi: 10.1136/bmjopen-2015-010643.</span>
<span class="docsum-journal-citation short-journal-citation">BMJ Open. 2016.</span>
<span class="citation-part">PMID: <span class="docsum-pmid">27881517</span></span>
<span class="free-resources spaced-citation-item citation-part">Free PMC article.</span>
<span class="publication-type spaced-citation-item citation-part">Review.</span>
</div>
</div>
</li>
<li class="full-docsum">
<div class="docsum-content" style="display:inline;">
<a class="docsum-title"
href="/26611124/"
ref="article_id=26611124&amp;linksrc=similar_articles_link&amp;ordinalpos=5"
data-ga-category="similar_article"
data-ga-action="26611124"
data-ga-label="">
Impact of Funding Source on Clinical Trial Results Including Cardiovascular Outcome Trials.
</a>
<div class="docsum-citation full-citation">
<span class="docsum-authors full-authors">Riaz H, Raza S, Khan MS, Riaz IB, Krasuski RA.</span>
<span class="docsum-authors short-authors">Riaz H, et al.</span>
<span class="docsum-journal-citation full-journal-citation">Am J Cardiol. 2015 Dec 15;116(12):1944-7. doi: 10.1016/j.amjcard.2015.09.034. Epub 2015 Oct 9.</span>
<span class="docsum-journal-citation short-journal-citation">Am J Cardiol. 2015.</span>
<span class="citation-part">PMID: <span class="docsum-pmid">26611124</span></span>
<span class="publication-type spaced-citation-item citation-part">Review.</span>
</div>
</div>
</li>
</ul>
<div class="actions-bar">
<a
class="show-all-linked-articles"
data-href="/?linkname=pubmed_pubmed&from_uid=22550198"
data-ga-category="similar_article"
data-ga-action="show_all"
>
See all similar articles
</a>
</div>
</div>
<div class="citedby-articles" id="citedby">
<h2 class="title">
Cited by
</h2>
<ul class="articles-list" id="citedby-articles-list">
<li class="full-docsum">
<div class="docsum-content" style="display:inline;">
<a class="docsum-title"
href="/23726436/"
ref="article_id=23726436&amp;linksrc=citedby_articles_link&amp;ordinalpos=1"
data-ga-category="cited_by"
data-ga-action="23726436"
data-ga-label="">
Characteristics of antimicrobial studies registered in the USA through ClinicalTrials.Gov.
</a>
<div class="docsum-citation full-citation">
<span class="docsum-authors full-authors">Stockmann C, Sherwin CM, Ampofo K, Hersh AL, Pavia AT, Byington CL, Ward RM, Spigarelli MG.</span>
<span class="docsum-authors short-authors">Stockmann C, et al.</span>
<span class="docsum-journal-citation full-journal-citation">Int J Antimicrob Agents. 2013 Aug;42(2):161-6. doi: 10.1016/j.ijantimicag.2013.04.019. Epub 2013 May 30.</span>
<span class="docsum-journal-citation short-journal-citation">Int J Antimicrob Agents. 2013.</span>
<span class="citation-part">PMID: <span class="docsum-pmid">23726436</span></span>
<span class="free-resources spaced-citation-item citation-part">Free PMC article.</span>
</div>
</div>
</li>
<li class="full-docsum">
<div class="docsum-content" style="display:inline;">
<a class="docsum-title"
href="/32845329/"
ref="article_id=32845329&amp;linksrc=citedby_articles_link&amp;ordinalpos=2"
data-ga-category="cited_by"
data-ga-action="32845329"
data-ga-label="">
Assessment of Trends in the Design, Accrual, and Completion of Trials Registered in ClinicalTrials.gov by Sponsor Type, 2000-2019.
</a>
<div class="docsum-citation full-citation">
<span class="docsum-authors full-authors">Gresham G, Meinert JL, Gresham AG, Meinert CL.</span>
<span class="docsum-authors short-authors">Gresham G, et al.</span>
<span class="docsum-journal-citation full-journal-citation">JAMA Netw Open. 2020 Aug 3;3(8):e2014682. doi: 10.1001/jamanetworkopen.2020.14682.</span>
<span class="docsum-journal-citation short-journal-citation">JAMA Netw Open. 2020.</span>
<span class="citation-part">PMID: <span class="docsum-pmid">32845329</span></span>
<span class="free-resources spaced-citation-item citation-part">Free PMC article.</span>
</div>
</div>
</li>
<li class="full-docsum">
<div class="docsum-content" style="display:inline;">
<a class="docsum-title"
href="/23564296/"
ref="article_id=23564296&amp;linksrc=citedby_articles_link&amp;ordinalpos=3"
data-ga-category="cited_by"
data-ga-action="23564296"
data-ga-label="">
Are current clinical trials in diabetes addressing important issues in diabetes care?
</a>
<div class="docsum-citation full-citation">
<span class="docsum-authors full-authors">Lakey WC, Barnard K, Batch BC, Chiswell K, Tasneem A, Green JB.</span>
<span class="docsum-authors short-authors">Lakey WC, et al.</span>
<span class="docsum-journal-citation full-journal-citation">Diabetologia. 2013 Jun;56(6):1226-35. doi: 10.1007/s00125-013-2890-4. Epub 2013 Apr 8.</span>
<span class="docsum-journal-citation short-journal-citation">Diabetologia. 2013.</span>
<span class="citation-part">PMID: <span class="docsum-pmid">23564296</span></span>
<span class="publication-type spaced-citation-item citation-part">Review.</span>
</div>
</div>
</li>
<li class="full-docsum">
<div class="docsum-content" style="display:inline;">
<a class="docsum-title"
href="/23369646/"
ref="article_id=23369646&amp;linksrc=citedby_articles_link&amp;ordinalpos=4"
data-ga-category="cited_by"
data-ga-action="23369646"
data-ga-label="">
Translational medicine as a permanent glue and force of clinical medicine and public health: perspectives (1) from 2012 Sino-American symposium on clinical and translational medicine.
</a>
<div class="docsum-citation full-citation">
<span class="docsum-authors full-authors">Zhou J, Wu D, Liu X, Yuan S, Yang X, Wang X.</span>
<span class="docsum-authors short-authors">Zhou J, et al.</span>
<span class="docsum-journal-citation full-journal-citation">Clin Transl Med. 2012 Oct 5;1(1):21. doi: 10.1186/2001-1326-1-21.</span>
<span class="docsum-journal-citation short-journal-citation">Clin Transl Med. 2012.</span>
<span class="citation-part">PMID: <span class="docsum-pmid">23369646</span></span>
<span class="free-resources spaced-citation-item citation-part">Free PMC article.</span>
</div>
</div>
</li>
<li class="full-docsum">
<div class="docsum-content" style="display:inline;">
<a class="docsum-title"
href="/27189012/"
ref="article_id=27189012&amp;linksrc=citedby_articles_link&amp;ordinalpos=5"
data-ga-category="cited_by"
data-ga-action="27189012"
data-ga-label="">
Learning disease relationships from clinical drug trials.
</a>
<div class="docsum-citation full-citation">
<span class="docsum-authors full-authors">Haslam B, Perez-Breva L.</span>
<span class="docsum-authors short-authors">Haslam B, et al.</span>
<span class="docsum-journal-citation full-journal-citation">J Am Med Inform Assoc. 2017 Jan;24(1):13-23. doi: 10.1093/jamia/ocw003. Epub 2016 May 17.</span>
<span class="docsum-journal-citation short-journal-citation">J Am Med Inform Assoc. 2017.</span>
<span class="citation-part">PMID: <span class="docsum-pmid">27189012</span></span>
<span class="free-resources spaced-citation-item citation-part">Free PMC article.</span>
</div>
</div>
</li>
</ul>
<div class="actions-bar">
<a
class="show-all-linked-articles"
data-href="/?linkname=pubmed_pubmed_citedin&from_uid=22550198"
data-ga-category="cited_by"
data-ga-action="show_all"
>
See all "Cited by" articles
</a>
</div>
</div>
<div id="publication-types" class="publication-types keywords-section">
<h2 class="title">
Publication types
</h2>
<ul class="keywords-list"><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link"
aria-label="Toggle dropdown menu for keyword Research Support, U.S. Gov&#x27;t, P.H.S."
tabindex="0"
aria-controls="keyword-actions-publication-types-0"
aria-expanded="false"
data-pinger-ignore>
Research Support, U.S. Gov&#x27;t, P.H.S.
</button><div id="keyword-actions-publication-types-0"
class="keyword-actions-dropdown dropdown dropdown-container"
hidden
aria-label="Dropdown menu for keyword Research Support, U.S. Gov&#x27;t, P.H.S."><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link"
href="/?term=%22Research+Support%2C+U.S.+Gov%27t%2C+P.H.S.%22%5Bpt%5D&amp;sort=date&amp;sort_order=desc"
data-href="/?term=%22Research+Support%2C+U.S.+Gov%27t%2C+P.H.S.%22%5Bpt%5D&amp;sort=date&amp;sort_order=desc"
ref="linksrc=search_in_pubmed_keyword_link&amp;keyword=&quot;Research Support, U.S. Gov&#x27;t, P.H.S.&quot;[pt]"
data-ga-category="search"
data-ga-action="pub_type"
data-ga-label="Research Support, U.S. Gov&#x27;t, P.H.S.">
Search in PubMed
</a></li><li><a class="search-in-mesh-link dropdown-block-link"
ref="linksrc=search_in_mesh_link"
href="https://www.ncbi.nlm.nih.gov/mesh?term=Research+Support%2C+U.S.+Gov%27t%2C+P.H.S."
data-ga-category="search_mesh"
data-ga-action="pub_type_link"
data-ga-label="Research Support, U.S. Gov&#x27;t, P.H.S.">
Search in MeSH
</a></li><li><a class="add-to-search-link dropdown-block-link"
ref="linksrc=add_to_search_link"
role="button"
data-search-term="&quot;Research Support, U.S. Gov&#x27;t, P.H.S.&quot;[pt]"
data-ga-category="search"
data-ga-action="add_to_search"
data-ga-label="&quot;Research Support, U.S. Gov&#x27;t, P.H.S.&quot;[pt]"
href="#">
Add to Search
</a></li></ul></div></div></div></li></ul>
</div>
<div id="mesh-terms" class="mesh-terms keywords-section">
<h2 class="title">
MeSH terms
</h2>
<ul class="keywords-list"><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link"
aria-label="Toggle dropdown menu for keyword Cardiovascular Diseases / therapy"
tabindex="0"
aria-controls="keyword-actions-mesh-terms-0"
aria-expanded="false"
data-pinger-ignore>
Cardiovascular Diseases / therapy
</button><div id="keyword-actions-mesh-terms-0"
class="keyword-actions-dropdown dropdown dropdown-container"
hidden
aria-label="Dropdown menu for keyword Cardiovascular Diseases / therapy"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link"
href="/?term=%22Cardiovascular+Diseases%2Ftherapy%22%5BMeSH%5D&amp;sort=date&amp;sort_order=desc"
data-href="/?term=%22Cardiovascular+Diseases%2Ftherapy%22%5BMeSH%5D&amp;sort=date&amp;sort_order=desc"
ref="linksrc=search_in_pubmed_keyword_link&amp;mesh=&quot;Cardiovascular Diseases/therapy&quot;[MeSH]"
data-ga-category="search"
data-ga-action="mesh_term"
data-ga-label="Cardiovascular Diseases / therapy">
Search in PubMed
</a></li><li><a class="search-in-mesh-link dropdown-block-link"
ref="linksrc=search_in_mesh_link"
href="https://www.ncbi.nlm.nih.gov/mesh?term=Cardiovascular+Diseases"
data-ga-category="search_mesh"
data-ga-action="mesh_term_link"
data-ga-label="Cardiovascular Diseases / therapy">
Search in MeSH
</a></li><li><a class="add-to-search-link dropdown-block-link"
ref="linksrc=add_to_search_link"
role="button"
data-search-term="&quot;Cardiovascular Diseases/therapy&quot;[MeSH]"
data-ga-category="search"
data-ga-action="add_to_search"
data-ga-label="&quot;Cardiovascular Diseases/therapy&quot;[MeSH]"
href="#">
Add to Search
</a></li></ul></div></div></div></li><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link major"
aria-label="Toggle dropdown menu for keyword Clinical Trials as Topic / standards*"
tabindex="0"
aria-controls="keyword-actions-mesh-terms-major-1"
aria-expanded="false"
data-pinger-ignore>
Clinical Trials as Topic / standards*
</button><div id="keyword-actions-mesh-terms-major-1"
class="keyword-actions-dropdown dropdown dropdown-container"
hidden
aria-label="Dropdown menu for keyword Clinical Trials as Topic / standards*"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link"
href="/?term=%22Clinical+Trials+as+Topic%2Fstandards%22%5BMAJR%5D&amp;sort=date&amp;sort_order=desc"
data-href="/?term=%22Clinical+Trials+as+Topic%2Fstandards%22%5BMAJR%5D&amp;sort=date&amp;sort_order=desc"
ref="linksrc=search_in_pubmed_keyword_link&amp;mesh=&quot;Clinical Trials as Topic/standards&quot;[MAJR]"
data-ga-category="search"
data-ga-action="mesh_term"
data-ga-label="Clinical Trials as Topic / standards*">
Search in PubMed
</a></li><li><a class="search-in-mesh-link dropdown-block-link"
ref="linksrc=search_in_mesh_link"
href="https://www.ncbi.nlm.nih.gov/mesh?term=Clinical+Trials+as+Topic"
data-ga-category="search_mesh"
data-ga-action="mesh_term_link"
data-ga-label="Clinical Trials as Topic / standards*">
Search in MeSH
</a></li><li><a class="add-to-search-link dropdown-block-link"
ref="linksrc=add_to_search_link"
role="button"
data-search-term="&quot;Clinical Trials as Topic/standards&quot;[MAJR]"
data-ga-category="search"
data-ga-action="add_to_search"
data-ga-label="&quot;Clinical Trials as Topic/standards&quot;[MAJR]"
href="#">
Add to Search
</a></li></ul></div></div></div></li><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link major"
aria-label="Toggle dropdown menu for keyword Clinical Trials as Topic / statistics &amp; numerical data*"
tabindex="0"
aria-controls="keyword-actions-mesh-terms-major-2"
aria-expanded="false"
data-pinger-ignore>
Clinical Trials as Topic / statistics &amp; numerical data*
</button><div id="keyword-actions-mesh-terms-major-2"
class="keyword-actions-dropdown dropdown dropdown-container"
hidden
aria-label="Dropdown menu for keyword Clinical Trials as Topic / statistics &amp; numerical data*"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link"
href="/?term=%22Clinical+Trials+as+Topic%2Fstatistics+and+numerical+data%22%5BMAJR%5D&amp;sort=date&amp;sort_order=desc"
data-href="/?term=%22Clinical+Trials+as+Topic%2Fstatistics+and+numerical+data%22%5BMAJR%5D&amp;sort=date&amp;sort_order=desc"
ref="linksrc=search_in_pubmed_keyword_link&amp;mesh=&quot;Clinical Trials as Topic/statistics and numerical data&quot;[MAJR]"
data-ga-category="search"
data-ga-action="mesh_term"
data-ga-label="Clinical Trials as Topic / statistics &amp; numerical data*">
Search in PubMed
</a></li><li><a class="search-in-mesh-link dropdown-block-link"
ref="linksrc=search_in_mesh_link"
href="https://www.ncbi.nlm.nih.gov/mesh?term=Clinical+Trials+as+Topic"
data-ga-category="search_mesh"
data-ga-action="mesh_term_link"
data-ga-label="Clinical Trials as Topic / statistics &amp; numerical data*">
Search in MeSH
</a></li><li><a class="add-to-search-link dropdown-block-link"
ref="linksrc=add_to_search_link"
role="button"
data-search-term="&quot;Clinical Trials as Topic/statistics and numerical data&quot;[MAJR]"
data-ga-category="search"
data-ga-action="add_to_search"
data-ga-label="&quot;Clinical Trials as Topic/statistics and numerical data&quot;[MAJR]"
href="#">
Add to Search
</a></li></ul></div></div></div></li><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link major"
aria-label="Toggle dropdown menu for keyword Databases, Factual*"
tabindex="0"
aria-controls="keyword-actions-mesh-terms-major-3"
aria-expanded="false"
data-pinger-ignore>
Databases, Factual*
</button><div id="keyword-actions-mesh-terms-major-3"
class="keyword-actions-dropdown dropdown dropdown-container"
hidden
aria-label="Dropdown menu for keyword Databases, Factual*"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link"
href="/?term=%22Databases%2C+Factual%22%5BMAJR%5D&amp;sort=date&amp;sort_order=desc"
data-href="/?term=%22Databases%2C+Factual%22%5BMAJR%5D&amp;sort=date&amp;sort_order=desc"
ref="linksrc=search_in_pubmed_keyword_link&amp;mesh=&quot;Databases, Factual&quot;[MAJR]"
data-ga-category="search"
data-ga-action="mesh_term"
data-ga-label="Databases, Factual*">
Search in PubMed
</a></li><li><a class="search-in-mesh-link dropdown-block-link"
ref="linksrc=search_in_mesh_link"
href="https://www.ncbi.nlm.nih.gov/mesh?term=Databases%2C+Factual"
data-ga-category="search_mesh"
data-ga-action="mesh_term_link"
data-ga-label="Databases, Factual*">
Search in MeSH
</a></li><li><a class="add-to-search-link dropdown-block-link"
ref="linksrc=add_to_search_link"
role="button"
data-search-term="&quot;Databases, Factual&quot;[MAJR]"
data-ga-category="search"
data-ga-action="add_to_search"
data-ga-label="&quot;Databases, Factual&quot;[MAJR]"
href="#">
Add to Search
</a></li></ul></div></div></div></li><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link"
aria-label="Toggle dropdown menu for keyword Drug Industry"
tabindex="0"
aria-controls="keyword-actions-mesh-terms-4"
aria-expanded="false"
data-pinger-ignore>
Drug Industry
</button><div id="keyword-actions-mesh-terms-4"
class="keyword-actions-dropdown dropdown dropdown-container"
hidden
aria-label="Dropdown menu for keyword Drug Industry"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link"
href="/?term=%22Drug+Industry%22%5BMeSH%5D&amp;sort=date&amp;sort_order=desc"
data-href="/?term=%22Drug+Industry%22%5BMeSH%5D&amp;sort=date&amp;sort_order=desc"
ref="linksrc=search_in_pubmed_keyword_link&amp;mesh=&quot;Drug Industry&quot;[MeSH]"
data-ga-category="search"
data-ga-action="mesh_term"
data-ga-label="Drug Industry">
Search in PubMed
</a></li><li><a class="search-in-mesh-link dropdown-block-link"
ref="linksrc=search_in_mesh_link"
href="https://www.ncbi.nlm.nih.gov/mesh?term=Drug+Industry"
data-ga-category="search_mesh"
data-ga-action="mesh_term_link"
data-ga-label="Drug Industry">
Search in MeSH
</a></li><li><a class="add-to-search-link dropdown-block-link"
ref="linksrc=add_to_search_link"
role="button"
data-search-term="&quot;Drug Industry&quot;[MeSH]"
data-ga-category="search"
data-ga-action="add_to_search"
data-ga-label="&quot;Drug Industry&quot;[MeSH]"
href="#">
Add to Search
</a></li></ul></div></div></div></li><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link"
aria-label="Toggle dropdown menu for keyword Humans"
tabindex="0"
aria-controls="keyword-actions-mesh-terms-5"
aria-expanded="false"
data-pinger-ignore>
Humans
</button><div id="keyword-actions-mesh-terms-5"
class="keyword-actions-dropdown dropdown dropdown-container"
hidden
aria-label="Dropdown menu for keyword Humans"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link"
href="/?term=%22Humans%22%5BMeSH%5D&amp;sort=date&amp;sort_order=desc"
data-href="/?term=%22Humans%22%5BMeSH%5D&amp;sort=date&amp;sort_order=desc"
ref="linksrc=search_in_pubmed_keyword_link&amp;mesh=&quot;Humans&quot;[MeSH]"
data-ga-category="search"
data-ga-action="mesh_term"
data-ga-label="Humans">
Search in PubMed
</a></li><li><a class="search-in-mesh-link dropdown-block-link"
ref="linksrc=search_in_mesh_link"
href="https://www.ncbi.nlm.nih.gov/mesh?term=Humans"
data-ga-category="search_mesh"
data-ga-action="mesh_term_link"
data-ga-label="Humans">
Search in MeSH
</a></li><li><a class="add-to-search-link dropdown-block-link"
ref="linksrc=add_to_search_link"
role="button"
data-search-term="&quot;Humans&quot;[MeSH]"
data-ga-category="search"
data-ga-action="add_to_search"
data-ga-label="&quot;Humans&quot;[MeSH]"
href="#">
Add to Search
</a></li></ul></div></div></div></li><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link"
aria-label="Toggle dropdown menu for keyword Mental Disorders / therapy"
tabindex="0"
aria-controls="keyword-actions-mesh-terms-6"
aria-expanded="false"
data-pinger-ignore>
Mental Disorders / therapy
</button><div id="keyword-actions-mesh-terms-6"
class="keyword-actions-dropdown dropdown dropdown-container"
hidden
aria-label="Dropdown menu for keyword Mental Disorders / therapy"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link"
href="/?term=%22Mental+Disorders%2Ftherapy%22%5BMeSH%5D&amp;sort=date&amp;sort_order=desc"
data-href="/?term=%22Mental+Disorders%2Ftherapy%22%5BMeSH%5D&amp;sort=date&amp;sort_order=desc"
ref="linksrc=search_in_pubmed_keyword_link&amp;mesh=&quot;Mental Disorders/therapy&quot;[MeSH]"
data-ga-category="search"
data-ga-action="mesh_term"
data-ga-label="Mental Disorders / therapy">
Search in PubMed
</a></li><li><a class="search-in-mesh-link dropdown-block-link"
ref="linksrc=search_in_mesh_link"
href="https://www.ncbi.nlm.nih.gov/mesh?term=Mental+Disorders"
data-ga-category="search_mesh"
data-ga-action="mesh_term_link"
data-ga-label="Mental Disorders / therapy">
Search in MeSH
</a></li><li><a class="add-to-search-link dropdown-block-link"
ref="linksrc=add_to_search_link"
role="button"
data-search-term="&quot;Mental Disorders/therapy&quot;[MeSH]"
data-ga-category="search"
data-ga-action="add_to_search"
data-ga-label="&quot;Mental Disorders/therapy&quot;[MeSH]"
href="#">
Add to Search
</a></li></ul></div></div></div></li><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link"
aria-label="Toggle dropdown menu for keyword National Institutes of Health (U.S.)"
tabindex="0"
aria-controls="keyword-actions-mesh-terms-7"
aria-expanded="false"
data-pinger-ignore>
National Institutes of Health (U.S.)
</button><div id="keyword-actions-mesh-terms-7"
class="keyword-actions-dropdown dropdown dropdown-container"
hidden
aria-label="Dropdown menu for keyword National Institutes of Health (U.S.)"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link"
href="/?term=%22National+Institutes+of+Health+%28U.S.%29%22%5BMeSH%5D&amp;sort=date&amp;sort_order=desc"
data-href="/?term=%22National+Institutes+of+Health+%28U.S.%29%22%5BMeSH%5D&amp;sort=date&amp;sort_order=desc"
ref="linksrc=search_in_pubmed_keyword_link&amp;mesh=&quot;National Institutes of Health (U.S.)&quot;[MeSH]"
data-ga-category="search"
data-ga-action="mesh_term"
data-ga-label="National Institutes of Health (U.S.)">
Search in PubMed
</a></li><li><a class="search-in-mesh-link dropdown-block-link"
ref="linksrc=search_in_mesh_link"
href="https://www.ncbi.nlm.nih.gov/mesh?term=National+Institutes+of+Health+%28U.S.%29"
data-ga-category="search_mesh"
data-ga-action="mesh_term_link"
data-ga-label="National Institutes of Health (U.S.)">
Search in MeSH
</a></li><li><a class="add-to-search-link dropdown-block-link"
ref="linksrc=add_to_search_link"
role="button"
data-search-term="&quot;National Institutes of Health (U.S.)&quot;[MeSH]"
data-ga-category="search"
data-ga-action="add_to_search"
data-ga-label="&quot;National Institutes of Health (U.S.)&quot;[MeSH]"
href="#">
Add to Search
</a></li></ul></div></div></div></li><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link"
aria-label="Toggle dropdown menu for keyword Neoplasms / therapy"
tabindex="0"
aria-controls="keyword-actions-mesh-terms-8"
aria-expanded="false"
data-pinger-ignore>
Neoplasms / therapy
</button><div id="keyword-actions-mesh-terms-8"
class="keyword-actions-dropdown dropdown dropdown-container"
hidden
aria-label="Dropdown menu for keyword Neoplasms / therapy"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link"
href="/?term=%22Neoplasms%2Ftherapy%22%5BMeSH%5D&amp;sort=date&amp;sort_order=desc"
data-href="/?term=%22Neoplasms%2Ftherapy%22%5BMeSH%5D&amp;sort=date&amp;sort_order=desc"
ref="linksrc=search_in_pubmed_keyword_link&amp;mesh=&quot;Neoplasms/therapy&quot;[MeSH]"
data-ga-category="search"
data-ga-action="mesh_term"
data-ga-label="Neoplasms / therapy">
Search in PubMed
</a></li><li><a class="search-in-mesh-link dropdown-block-link"
ref="linksrc=search_in_mesh_link"
href="https://www.ncbi.nlm.nih.gov/mesh?term=Neoplasms"
data-ga-category="search_mesh"
data-ga-action="mesh_term_link"
data-ga-label="Neoplasms / therapy">
Search in MeSH
</a></li><li><a class="add-to-search-link dropdown-block-link"
ref="linksrc=add_to_search_link"
role="button"
data-search-term="&quot;Neoplasms/therapy&quot;[MeSH]"
data-ga-category="search"
data-ga-action="add_to_search"
data-ga-label="&quot;Neoplasms/therapy&quot;[MeSH]"
href="#">
Add to Search
</a></li></ul></div></div></div></li><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link"
aria-label="Toggle dropdown menu for keyword Randomized Controlled Trials as Topic"
tabindex="0"
aria-controls="keyword-actions-mesh-terms-9"
aria-expanded="false"
data-pinger-ignore>
Randomized Controlled Trials as Topic
</button><div id="keyword-actions-mesh-terms-9"
class="keyword-actions-dropdown dropdown dropdown-container"
hidden
aria-label="Dropdown menu for keyword Randomized Controlled Trials as Topic"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link"
href="/?term=%22Randomized+Controlled+Trials+as+Topic%22%5BMeSH%5D&amp;sort=date&amp;sort_order=desc"
data-href="/?term=%22Randomized+Controlled+Trials+as+Topic%22%5BMeSH%5D&amp;sort=date&amp;sort_order=desc"
ref="linksrc=search_in_pubmed_keyword_link&amp;mesh=&quot;Randomized Controlled Trials as Topic&quot;[MeSH]"
data-ga-category="search"
data-ga-action="mesh_term"
data-ga-label="Randomized Controlled Trials as Topic">
Search in PubMed
</a></li><li><a class="search-in-mesh-link dropdown-block-link"
ref="linksrc=search_in_mesh_link"
href="https://www.ncbi.nlm.nih.gov/mesh?term=Randomized+Controlled+Trials+as+Topic"
data-ga-category="search_mesh"
data-ga-action="mesh_term_link"
data-ga-label="Randomized Controlled Trials as Topic">
Search in MeSH
</a></li><li><a class="add-to-search-link dropdown-block-link"
ref="linksrc=add_to_search_link"
role="button"
data-search-term="&quot;Randomized Controlled Trials as Topic&quot;[MeSH]"
data-ga-category="search"
data-ga-action="add_to_search"
data-ga-label="&quot;Randomized Controlled Trials as Topic&quot;[MeSH]"
href="#">
Add to Search
</a></li></ul></div></div></div></li><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link major"
aria-label="Toggle dropdown menu for keyword Registries / statistics &amp; numerical data*"
tabindex="0"
aria-controls="keyword-actions-mesh-terms-major-10"
aria-expanded="false"
data-pinger-ignore>
Registries / statistics &amp; numerical data*
</button><div id="keyword-actions-mesh-terms-major-10"
class="keyword-actions-dropdown dropdown dropdown-container"
hidden
aria-label="Dropdown menu for keyword Registries / statistics &amp; numerical data*"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link"
href="/?term=%22Registries%2Fstatistics+and+numerical+data%22%5BMAJR%5D&amp;sort=date&amp;sort_order=desc"
data-href="/?term=%22Registries%2Fstatistics+and+numerical+data%22%5BMAJR%5D&amp;sort=date&amp;sort_order=desc"
ref="linksrc=search_in_pubmed_keyword_link&amp;mesh=&quot;Registries/statistics and numerical data&quot;[MAJR]"
data-ga-category="search"
data-ga-action="mesh_term"
data-ga-label="Registries / statistics &amp; numerical data*">
Search in PubMed
</a></li><li><a class="search-in-mesh-link dropdown-block-link"
ref="linksrc=search_in_mesh_link"
href="https://www.ncbi.nlm.nih.gov/mesh?term=Registries"
data-ga-category="search_mesh"
data-ga-action="mesh_term_link"
data-ga-label="Registries / statistics &amp; numerical data*">
Search in MeSH
</a></li><li><a class="add-to-search-link dropdown-block-link"
ref="linksrc=add_to_search_link"
role="button"
data-search-term="&quot;Registries/statistics and numerical data&quot;[MAJR]"
data-ga-category="search"
data-ga-action="add_to_search"
data-ga-label="&quot;Registries/statistics and numerical data&quot;[MAJR]"
href="#">
Add to Search
</a></li></ul></div></div></div></li><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link"
aria-label="Toggle dropdown menu for keyword Research Design"
tabindex="0"
aria-controls="keyword-actions-mesh-terms-11"
aria-expanded="false"
data-pinger-ignore>
Research Design
</button><div id="keyword-actions-mesh-terms-11"
class="keyword-actions-dropdown dropdown dropdown-container"
hidden
aria-label="Dropdown menu for keyword Research Design"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link"
href="/?term=%22Research+Design%22%5BMeSH%5D&amp;sort=date&amp;sort_order=desc"
data-href="/?term=%22Research+Design%22%5BMeSH%5D&amp;sort=date&amp;sort_order=desc"
ref="linksrc=search_in_pubmed_keyword_link&amp;mesh=&quot;Research Design&quot;[MeSH]"
data-ga-category="search"
data-ga-action="mesh_term"
data-ga-label="Research Design">
Search in PubMed
</a></li><li><a class="search-in-mesh-link dropdown-block-link"
ref="linksrc=search_in_mesh_link"
href="https://www.ncbi.nlm.nih.gov/mesh?term=Research+Design"
data-ga-category="search_mesh"
data-ga-action="mesh_term_link"
data-ga-label="Research Design">
Search in MeSH
</a></li><li><a class="add-to-search-link dropdown-block-link"
ref="linksrc=add_to_search_link"
role="button"
data-search-term="&quot;Research Design&quot;[MeSH]"
data-ga-category="search"
data-ga-action="add_to_search"
data-ga-label="&quot;Research Design&quot;[MeSH]"
href="#">
Add to Search
</a></li></ul></div></div></div></li><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link"
aria-label="Toggle dropdown menu for keyword Research Support as Topic"
tabindex="0"
aria-controls="keyword-actions-mesh-terms-12"
aria-expanded="false"
data-pinger-ignore>
Research Support as Topic
</button><div id="keyword-actions-mesh-terms-12"
class="keyword-actions-dropdown dropdown dropdown-container"
hidden
aria-label="Dropdown menu for keyword Research Support as Topic"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link"
href="/?term=%22Research+Support+as+Topic%22%5BMeSH%5D&amp;sort=date&amp;sort_order=desc"
data-href="/?term=%22Research+Support+as+Topic%22%5BMeSH%5D&amp;sort=date&amp;sort_order=desc"
ref="linksrc=search_in_pubmed_keyword_link&amp;mesh=&quot;Research Support as Topic&quot;[MeSH]"
data-ga-category="search"
data-ga-action="mesh_term"
data-ga-label="Research Support as Topic">
Search in PubMed
</a></li><li><a class="search-in-mesh-link dropdown-block-link"
ref="linksrc=search_in_mesh_link"
href="https://www.ncbi.nlm.nih.gov/mesh?term=Research+Support+as+Topic"
data-ga-category="search_mesh"
data-ga-action="mesh_term_link"
data-ga-label="Research Support as Topic">
Search in MeSH
</a></li><li><a class="add-to-search-link dropdown-block-link"
ref="linksrc=add_to_search_link"
role="button"
data-search-term="&quot;Research Support as Topic&quot;[MeSH]"
data-ga-category="search"
data-ga-action="add_to_search"
data-ga-label="&quot;Research Support as Topic&quot;[MeSH]"
href="#">
Add to Search
</a></li></ul></div></div></div></li><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link"
aria-label="Toggle dropdown menu for keyword Sample Size"
tabindex="0"
aria-controls="keyword-actions-mesh-terms-13"
aria-expanded="false"
data-pinger-ignore>
Sample Size
</button><div id="keyword-actions-mesh-terms-13"
class="keyword-actions-dropdown dropdown dropdown-container"
hidden
aria-label="Dropdown menu for keyword Sample Size"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link"
href="/?term=%22Sample+Size%22%5BMeSH%5D&amp;sort=date&amp;sort_order=desc"
data-href="/?term=%22Sample+Size%22%5BMeSH%5D&amp;sort=date&amp;sort_order=desc"
ref="linksrc=search_in_pubmed_keyword_link&amp;mesh=&quot;Sample Size&quot;[MeSH]"
data-ga-category="search"
data-ga-action="mesh_term"
data-ga-label="Sample Size">
Search in PubMed
</a></li><li><a class="search-in-mesh-link dropdown-block-link"
ref="linksrc=search_in_mesh_link"
href="https://www.ncbi.nlm.nih.gov/mesh?term=Sample+Size"
data-ga-category="search_mesh"
data-ga-action="mesh_term_link"
data-ga-label="Sample Size">
Search in MeSH
</a></li><li><a class="add-to-search-link dropdown-block-link"
ref="linksrc=add_to_search_link"
role="button"
data-search-term="&quot;Sample Size&quot;[MeSH]"
data-ga-category="search"
data-ga-action="add_to_search"
data-ga-label="&quot;Sample Size&quot;[MeSH]"
href="#">
Add to Search
</a></li></ul></div></div></div></li><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link"
aria-label="Toggle dropdown menu for keyword United States"
tabindex="0"
aria-controls="keyword-actions-mesh-terms-14"
aria-expanded="false"
data-pinger-ignore>
United States
</button><div id="keyword-actions-mesh-terms-14"
class="keyword-actions-dropdown dropdown dropdown-container"
hidden
aria-label="Dropdown menu for keyword United States"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link"
href="/?term=%22United+States%22%5BMeSH%5D&amp;sort=date&amp;sort_order=desc"
data-href="/?term=%22United+States%22%5BMeSH%5D&amp;sort=date&amp;sort_order=desc"
ref="linksrc=search_in_pubmed_keyword_link&amp;mesh=&quot;United States&quot;[MeSH]"
data-ga-category="search"
data-ga-action="mesh_term"
data-ga-label="United States">
Search in PubMed
</a></li><li><a class="search-in-mesh-link dropdown-block-link"
ref="linksrc=search_in_mesh_link"
href="https://www.ncbi.nlm.nih.gov/mesh?term=United+States"
data-ga-category="search_mesh"
data-ga-action="mesh_term_link"
data-ga-label="United States">
Search in MeSH
</a></li><li><a class="add-to-search-link dropdown-block-link"
ref="linksrc=add_to_search_link"
role="button"
data-search-term="&quot;United States&quot;[MeSH]"
data-ga-category="search"
data-ga-action="add_to_search"
data-ga-label="&quot;United States&quot;[MeSH]"
href="#">
Add to Search
</a></li></ul></div></div></div></li></ul>
</div>
<div id="related-links" class="related-links">
<h2 class="title">
Related information
</h2>
<ul class="related-links-list"><li><a title="PubMed links associated with Books" href="https://www.ncbi.nlm.nih.gov/books?linkname=pubmed_books_refs&amp;from_uid=22550198"
ref="log$=recordlinks&logdbfrom=pubmed&ncbi_uid=22550198&ordinalpos=1&linkpos=1">
Cited in Books
</a></li></ul>
</div>
<div id="grants" class="grants">
<h2 class="title">
Grants and funding
</h2>
<div class="grants-list"><ul id="grants-head-list"><li class="grant-item"><a
title="All articles for grant U19FD003800/FD/FDA HHS/United States"
href="/?term=U19FD003800%2FFD%2FFDA+HHS%2FUnited+States%5BGrants+and+Funding%5D&amp;sort=date&amp;sort_order=desc"
ref="linksrc=grant_link"
data-ga-category="search"
data-ga-action="grant"
data-ga-label="U19FD003800"
>
U19FD003800/FD/FDA HHS/United States
</a></li></ul></div>
</div>
<div id="linkout" class="linkout">
<h2 class="title">
LinkOut - more resources
</h2>
<ul class="linkout-list"><li><h3 class="linkout-category">Full Text Sources</h3><ul class="linkout-category-links"><li><a
href="http://ovidsp.ovid.com/ovidweb.cgi?T=JS&amp;PAGE=linkout&amp;SEARCH=22550198.ui"
target="_blank"
rel="noopener"
ref="linksrc=linkout_link&PrId=3682&uid=22550198&db=pubmed&itool=Abstract&log$=linkoutlink&nlmid=7501160"
data-ga-category="link_out"
data-ga-action="Full Text Sources"
data-ga-label="Ovid Technologies, Inc."
>
Ovid Technologies, Inc.
</a></li><li><a
href="https://jamanetwork.com/journals/jama/fullarticle/10.1001/jama.2012.3424"
target="_blank"
rel="noopener"
ref="linksrc=linkout_link&PrId=7898&uid=22550198&db=pubmed&itool=Abstract&log$=linkoutlink&nlmid=7501160"
data-ga-category="link_out"
data-ga-action="Full Text Sources"
data-ga-label="Silverchair Information Systems"
>
Silverchair Information Systems
</a></li></ul></li><li><h3 class="linkout-category">Medical</h3><ul class="linkout-category-links"><li><a
href="https://medlineplus.gov/clinicaltrials.html"
target="_blank"
rel="noopener"
ref="linksrc=linkout_link&PrId=3162&uid=22550198&db=pubmed&itool=Abstract&log$=linkoutlink&nlmid=7501160"
data-ga-category="link_out"
data-ga-action="Medical"
data-ga-label="MedlinePlus Health Information"
>
MedlinePlus Health Information
</a></li></ul></li></ul>
</div>
</main>
<div class="overlay" role="dialog" aria-label="Full Text Links Dialog">
<div id="full-text-links-dialog" class="dialog full-text-links-dialog">
<strong class="title">Full text links</strong>
<button class="close-overlay" tabindex="2">[x]</button>
<div class="full-text-links-list">
<a class="link-item
dialog-focus"
href="https://jamanetwork.com/journals/jama/fullarticle/10.1001/jama.2012.3424"
target="_blank"
rel="noopener"
ref="linksrc=fulltextorjournal_fulltext&amp;is_pmc=False&amp;PrId=7898&amp;itool=Abstract-def&amp;log$=linkouticon&amp;uid=22550198&amp;db=pubmed&amp;nlmid=7501160"
title="See full text options at Silverchair Information Systems"
tabindex="1"
data-ga-category="full_text"
data-ga-action="Silverchair Information Systems"
data-ga-label="22550198"
><img src="https://cdn.ncbi.nlm.nih.gov/corehtml/query/egifs/https:--jama.jamanetwork.com-images-PUBMED_JAMA_full.gif" alt="Silverchair Information Systems full text link"><span class="text">
Silverchair Information Systems
</span></a>
</div>
</div>
</div>
<div class="overlay" role="dialog" aria-label="Citation Dialog">
<div class="dialog citation-dialog">
<button class="close-overlay" tabindex="1">[x]</button>
<div class="title">Cite</div>
<div class="citation-text-block">
<div class="citation-text"></div>
<div class="citation-actions">
<button
class="copy-button dialog-focus"
data-ga-category="save_share"
data-ga-action="cite"
data-ga-label="copy"
tabindex="2">
Copy
</button>
<form method="post">
<input type="hidden" name="csrfmiddlewaretoken" value="rflWEJ0KQSqzRd066f1777SfRtZYb5BmI251hzt6qtd3LE6WJyE9BfoTpxHa4G9G">
<button type="submit"
class="export-button"
data-ga-category="save_share"
data-ga-action="cite"
data-ga-label="download"
title="Download a file for external citation management software"
tabindex="3">
<span class="download-title">Download .nbib</span>
<span class="download-title-mobile">.nbib</span>
</button>
</form>
<div class="citation-style-selector-wrapper">
<label class="selector-label">Format:</label>
<select aria-label="Format" class="citation-style-selector" tabindex="4">
<option data-style-url-name="ama"
value="AMA"
>
AMA
</option>
<option data-style-url-name="apa"
value="APA"
>
APA
</option>
<option data-style-url-name="mla"
value="MLA"
>
MLA
</option>
<option data-style-url-name="nlm"
value="NLM"
selected="selected">
NLM
</option>
</select>
</div>
</div>
</div>
</div>
</div>
<div class="overlay" role="dialog" aria-label="More Actions Dialog">
<div id="more-actions-dialog" class="dialog more-actions-dialog">
<strong class="title">Send To</strong>
<ul class="more-actions-links">
<li><a id="clipboard-trigger" role="button" class="submit-button clipboard-trigger clipboard-trigger-target dialog-focus link-item " href="#">Clipboard</a></li>
<li><a class="email-trigger link-item" role="button" href="#">Email</a></li>
<li><a class="save-trigger link-item" role="button" href="#">Save</a></li>
<li><a class="link-item" role="button" href="https://account.ncbi.nlm.nih.gov/?back_url=https%3A%2F%2Fpubmed.ncbi.nlm.nih.gov%2F22550198%2F%23open-bibliography-panel">My Bibliography</a></li>
<li><a class="link-item" role="button" href="https://account.ncbi.nlm.nih.gov/?back_url=https%3A%2F%2Fpubmed.ncbi.nlm.nih.gov%2F22550198%2F%23open-collections-panel">Collections</a></li>
<li><a class="citation-manager-trigger link-item" role="button" href="#">Citation Manager</a></li>
</ul>
<button class="close-overlay">[x]</button>
</div>
</div>
</div>
<div id="ncbi-footer">
<div class="literature-footer" role="complementary" title="Links to NCBI Literature Resources">
<div class="usa-grid">
<p class="literature-footer-text">NCBI Literature Resources</p>
<p class="literature-footer-text">
<a class="literature-footer-link" data-ga-category="literature_resources" data-ga-action="mesh_link" href="https://www.ncbi.nlm.nih.gov/mesh/">MeSH</a>
<a class="literature-footer-link" data-ga-category="literature_resources" data-ga-action="pmc_link" href="https://www.ncbi.nlm.nih.gov/pmc/">PMC</a>
<a class="literature-footer-link" data-ga-category="literature_resources" data-ga-action="bookshelf_link" href="https://www.ncbi.nlm.nih.gov/books">Bookshelf</a>
<a class="literature-footer-link" data-ga-category="literature_resources" data-ga-action="disclaimer_link" href="/disclaimer/">Disclaimer</a>
</p>
<p class="literature-footer-text attribution-statement">The PubMed wordmark and PubMed logo are registered trademarks of the U.S. Department of Health and Human Services (HHS). Unauthorized use of these marks is strictly prohibited.</p>
</div>
</div>
<!-- ========== BEGIN FOOTER ========== -->
<footer>
<section class="icon-section">
<div id="icon-section-header" class="icon-section_header">Follow NCBI</div>
<div class="grid-container container">
<div class="icon-section_container">
<a class="footer-icon" id="footer_twitter" href="https://twitter.com/ncbi" aria-label="Twitter">
<svg width="40" height="40" viewBox="0 0 40 37" fill="none" xmlns="http://www.w3.org/2000/svg">
<title>Twitter</title>
<g id="twitterx1008">
<path id="path1008"
d="M6.06736 7L16.8778 20.8991L6.00001 32.2H10.2L18.6 23.1L25.668 32.2H34L22.8 17.5L31.9 7H28.4L20.7 15.4L14.401 7H6.06898H6.06736ZM9.66753 8.73423H12.9327L29.7327 30.4658H26.5697L9.66753 8.73423Z"
fill="#5B616B"/>
</g>
</svg>
</a>
<a class="footer-icon" id="footer_facebook" href="https://www.facebook.com/ncbi.nlm" aria-label="Facebook"><svg
data-name="Layer 1" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 300 300">
<title>Facebook</title>
<path class="cls-11"
d="M210.5,115.12H171.74V97.82c0-8.14,5.39-10,9.19-10h27.14V52l-39.32-.12c-35.66,0-42.42,26.68-42.42,43.77v19.48H99.09v36.32h27.24v109h45.41v-109h35Z">
</path>
</svg></a>
<a class="footer-icon" id="footer_linkedin"
href="https://www.linkedin.com/company/ncbinlm"
aria-label="LinkedIn"><svg data-name="Layer 1" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 300 300">
<title>LinkedIn</title>
<path class="cls-11"
d="M101.64,243.37H57.79v-114h43.85Zm-22-131.54h-.26c-13.25,0-21.82-10.36-21.82-21.76,0-11.65,8.84-21.15,22.33-21.15S101.7,78.72,102,90.38C102,101.77,93.4,111.83,79.63,111.83Zm100.93,52.61A17.54,17.54,0,0,0,163,182v61.39H119.18s.51-105.23,0-114H163v13a54.33,54.33,0,0,1,34.54-12.66c26,0,44.39,18.8,44.39,55.29v58.35H198.1V182A17.54,17.54,0,0,0,180.56,164.44Z">
</path>
</svg></a>
<a class="footer-icon" id="footer_github" href="https://github.com/ncbi" aria-label="GitHub"><svg
data-name="Layer 1" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 300 300">
<defs>
<style>
.cls-11,
.cls-12 {
fill: #737373;
}
.cls-11 {
fill-rule: evenodd;
}
</style>
</defs>
<title>GitHub</title>
<path class="cls-11"
d="M151.36,47.28a105.76,105.76,0,0,0-33.43,206.1c5.28,1,7.22-2.3,7.22-5.09,0-2.52-.09-10.85-.14-19.69-29.42,6.4-35.63-12.48-35.63-12.48-4.81-12.22-11.74-15.47-11.74-15.47-9.59-6.56.73-6.43.73-6.43,10.61.75,16.21,10.9,16.21,10.9,9.43,16.17,24.73,11.49,30.77,8.79,1-6.83,3.69-11.5,6.71-14.14C108.57,197.1,83.88,188,83.88,147.51a40.92,40.92,0,0,1,10.9-28.39c-1.1-2.66-4.72-13.42,1-28,0,0,8.88-2.84,29.09,10.84a100.26,100.26,0,0,1,53,0C198,88.3,206.9,91.14,206.9,91.14c5.76,14.56,2.14,25.32,1,28a40.87,40.87,0,0,1,10.89,28.39c0,40.62-24.74,49.56-48.29,52.18,3.79,3.28,7.17,9.71,7.17,19.58,0,14.15-.12,25.54-.12,29,0,2.82,1.9,6.11,7.26,5.07A105.76,105.76,0,0,0,151.36,47.28Z">
</path>
<path class="cls-12"
d="M85.66,199.12c-.23.52-1.06.68-1.81.32s-1.2-1.06-.95-1.59,1.06-.69,1.82-.33,1.21,1.07.94,1.6Zm-1.3-1">
</path>
<path class="cls-12"
d="M90,203.89c-.51.47-1.49.25-2.16-.49a1.61,1.61,0,0,1-.31-2.19c.52-.47,1.47-.25,2.17.49s.82,1.72.3,2.19Zm-1-1.08">
</path>
<path class="cls-12"
d="M94.12,210c-.65.46-1.71,0-2.37-.91s-.64-2.07,0-2.52,1.7,0,2.36.89.65,2.08,0,2.54Zm0,0"></path>
<path class="cls-12"
d="M99.83,215.87c-.58.64-1.82.47-2.72-.41s-1.18-2.06-.6-2.7,1.83-.46,2.74.41,1.2,2.07.58,2.7Zm0,0">
</path>
<path class="cls-12"
d="M107.71,219.29c-.26.82-1.45,1.2-2.64.85s-2-1.34-1.74-2.17,1.44-1.23,2.65-.85,2,1.32,1.73,2.17Zm0,0">
</path>
<path class="cls-12"
d="M116.36,219.92c0,.87-1,1.59-2.24,1.61s-2.29-.68-2.3-1.54,1-1.59,2.26-1.61,2.28.67,2.28,1.54Zm0,0">
</path>
<path class="cls-12"
d="M124.42,218.55c.15.85-.73,1.72-2,1.95s-2.37-.3-2.52-1.14.73-1.75,2-2,2.37.29,2.53,1.16Zm0,0"></path>
</svg></a>
<a class="footer-icon" id="footer_blog" href="https://ncbiinsights.ncbi.nlm.nih.gov/" aria-label="Blog">
<svg id="Layer_1" data-name="Layer 1" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 40 40"><defs><style>.cls-1{fill:#737373;}</style></defs><path class="cls-1" d="M14,30a4,4,0,1,1-4-4,4,4,0,0,1,4,4Zm11,3A19,19,0,0,0,7.05,15a1,1,0,0,0-1,1v3a1,1,0,0,0,.93,1A14,14,0,0,1,20,33.07,1,1,0,0,0,21,34h3a1,1,0,0,0,1-1Zm9,0A28,28,0,0,0,7,6,1,1,0,0,0,6,7v3a1,1,0,0,0,1,1A23,23,0,0,1,29,33a1,1,0,0,0,1,1h3A1,1,0,0,0,34,33Z"/></svg>
</a>
</div>
</div>
</section>
<section class="container-fluid bg-primary">
<div class="container pt-5">
<div class="row mt-3">
<div class="col-lg-3 col-12">
<p><a class="text-white" href="https://www.nlm.nih.gov/socialmedia/index.html">Connect with NLM</a></p>
<ul class="list-inline social_media">
<li class="list-inline-item"><a href="https://twitter.com/NLM_NIH" aria-label="Twitter"
target="_blank" rel="noopener noreferrer">
<svg width="35" height="35" viewBox="0 0 38 35" fill="none" xmlns="http://www.w3.org/2000/svg">
<title>Twitter</title>
<g id="twitterx1009" clip-path="url(#clip0_65276_3946)">
<path id="Vector" d="M17.5006 34.6565C26.9761 34.6565 34.6575 26.9751 34.6575 17.4996C34.6575 8.02416 26.9761 0.342773 17.5006 0.342773C8.02514 0.342773 0.34375 8.02416 0.34375 17.4996C0.34375 26.9751 8.02514 34.6565 17.5006 34.6565Z" fill="#205493" stroke="white" stroke-width="1.2" stroke-miterlimit="10"></path>
<path id="path1009" d="M8.54811 8.5L16.2698 18.4279L8.50001 26.5H11.5L17.5 20L22.5486 26.5H28.5L20.5 16L27 8.5H24.5L19 14.5L14.5007 8.5H8.54927H8.54811ZM11.1197 9.73873H13.4519L25.4519 25.2613H23.1926L11.1197 9.73873Z" fill="white"></path>
</g>
<defs>
<clipPath id="clip0_65276_3946">
<rect width="38" height="38" fill="white"></rect>
</clipPath>
</defs>
</svg></a>
</li>
<li class="list-inline-item"><a href="https://www.facebook.com/nationallibraryofmedicine"
aria-label="Facebook" rel="noopener noreferrer" target="_blank">
<svg version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px"
y="0px" viewBox="0 0 249 249" style="enable-background:new 0 0 249 249;" xml:space="preserve">
<style type="text/css">
.st10 {
fill: #FFFFFF;
}
.st110 {
fill: none;
stroke: #FFFFFF;
stroke-width: 8;
stroke-miterlimit: 10;
}
</style>
<title>SM-Facebook</title>
<g>
<g>
<path class="st10" d="M159,99.1h-24V88.4c0-5,3.3-6.2,5.7-6.2h16.8V60l-24.4-0.1c-22.1,0-26.2,16.5-26.2,27.1v12.1H90v22.5h16.9
v67.5H135v-67.5h21.7L159,99.1z"></path>
</g>
</g>
<circle class="st110" cx="123.6" cy="123.2" r="108.2"></circle>
</svg>
</a></li>
<li class="list-inline-item"><a href="https://www.youtube.com/user/NLMNIH" aria-label="Youtube"
target="_blank" rel="noopener noreferrer"><svg version="1.1" xmlns="http://www.w3.org/2000/svg"
xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px" viewBox="0 0 249 249"
style="enable-background:new 0 0 249 249;" xml:space="preserve">
<title>SM-Youtube</title>
<style type="text/css">
.st4 {
fill: none;
stroke: #FFFFFF;
stroke-width: 8;
stroke-miterlimit: 10;
}
.st5 {
fill: #FFFFFF;
}
</style>
<circle class="st4" cx="124.2" cy="123.4" r="108.2"></circle>
<g transform="translate(0,-952.36218)">
<path class="st5"
d="M88.4,1037.4c-10.4,0-18.7,8.3-18.7,18.7v40.1c0,10.4,8.3,18.7,18.7,18.7h72.1c10.4,0,18.7-8.3,18.7-18.7
v-40.1c0-10.4-8.3-18.7-18.7-18.7H88.4z M115.2,1058.8l29.4,17.4l-29.4,17.4V1058.8z"></path>
</g>
</svg></a></li>
</ul>
</div>
<div class="col-lg-3 col-12">
<p class="address_footer text-white">National Library of Medicine<br>
<a href="https://www.google.com/maps/place/8600+Rockville+Pike,+Bethesda,+MD+20894/@38.9959508,-77.101021,17z/data=!3m1!4b1!4m5!3m4!1s0x89b7c95e25765ddb:0x19156f88b27635b8!8m2!3d38.9959508!4d-77.0988323"
class="text-white" target="_blank" rel="noopener noreferrer">8600 Rockville Pike<br>
Bethesda, MD 20894</a></p>
</div>
<div class="col-lg-3 col-12 centered-lg">
<p><a href="https://www.nlm.nih.gov/web_policies.html" class="text-white">Web Policies</a><br>
<a href="https://www.nih.gov/institutes-nih/nih-office-director/office-communications-public-liaison/freedom-information-act-office"
class="text-white">FOIA</a><br>
<a href="https://www.hhs.gov/vulnerability-disclosure-policy/index.html" class="text-white" id="vdp">HHS Vulnerability Disclosure</a></p>
</div>
<div class="col-lg-3 col-12 centered-lg">
<p><a class="supportLink text-white" href="https://support.nlm.nih.gov/">Help</a><br>
<a href="https://www.nlm.nih.gov/accessibility.html" class="text-white">Accessibility</a><br>
<a href="https://www.nlm.nih.gov/careers/careers.html" class="text-white">Careers</a></p>
</div>
</div>
<div class="row">
<div class="col-lg-12 centered-lg">
<nav class="bottom-links">
<ul class="mt-3">
<li>
<a class="text-white" href="//www.nlm.nih.gov/">NLM</a>
</li>
<li>
<a class="text-white"
href="https://www.nih.gov/">NIH</a>
</li>
<li>
<a class="text-white" href="https://www.hhs.gov/">HHS</a>
</li>
<li>
<a
class="text-white" href="https://www.usa.gov/">USA.gov</a>
</li>
</ul>
</nav>
</div>
</div>
</div>
</section>
</footer>
<!-- ========== END FOOTER ========== -->
<!-- javascript to inject NWDS meta tags. Note: value of nwds_version is updated by "npm version" command -->
<script type="text/javascript">
var nwds_version = "1.2.3";
var meta_nwds_ver = document.createElement('meta');
meta_nwds_ver.name = 'ncbi_nwds_ver';
meta_nwds_ver.content = nwds_version;
document.getElementsByTagName('head')[0].appendChild(meta_nwds_ver);
var meta_nwds = document.createElement('meta');
meta_nwds.name = 'ncbi_nwds';
meta_nwds.content = 'yes';
document.getElementsByTagName('head')[0].appendChild(meta_nwds);
var alertsUrl = "/core/alerts/alerts.js";
if (typeof ncbiBaseUrl !== 'undefined') {
alertsUrl = ncbiBaseUrl + alertsUrl;
}
</script>
</div>
<!-- jQuery with plugins -->
<script src="https://cdn.ncbi.nlm.nih.gov/pubmed/277eb475-38df-4990-a0ee-0080b04e86fc/CACHE/js/output.293fbf76aa18.js"></script>
<!-- Project base scripts -->
<script src="https://cdn.ncbi.nlm.nih.gov/pubmed/277eb475-38df-4990-a0ee-0080b04e86fc/CACHE/js/output.550e9c8906a2.js"></script>
<script>
ncbi.awesome.basePage.init({
userInfo: {
isLoggedIn: false,
username: "",
loginUrl: "https://account.ncbi.nlm.nih.gov/?back_url=https%3A%2F%2Fpubmed.ncbi.nlm.nih.gov%2F22550198%2F",
logoutUrl: "https://www.ncbi.nlm.nih.gov/account/signout/?back_url=https%3A//pubmed.ncbi.nlm.nih.gov/22550198/"
},
baseUrl: 'https://www.ncbi.nlm.nih.gov',
noSessionCookieName: "pm-ns",
searchIdCookieName: "pm-sid",
adjNavSearchIdCookieName: "pm-adjnav-sid",
searchFormSubmittedCookieName: "pm-sfs",
isOnSearchPageCookieName: "pm-iosp",
backToSearchCookieName: "pm-btsl",
clinicalSeeAllCookieName: "pm-csa",
jsCookieDomain: "pubmed.ncbi.nlm.nih.gov",
userShareRequestFailed: "",
noSharedSettings: "myncbi_no_shared_settings",
noSharedAccount: "myncbi_no_shared_account"
});
</script>
<script type="module">
import dismissableNCBIAlert from "https://cdn.ncbi.nlm.nih.gov/pubmed/277eb475-38df-4990-a0ee-0080b04e86fc/core/dismissable-ncbi-alert.js";
jQuery.getScript("https://www.ncbi.nlm.nih.gov/core/alerts/alerts.js", function () {
galert(['body > *:last-child']);
dismissableNCBIAlert();
}).fail(function() {
});
</script>
<script defer type="text/javascript" src="https://cdn.ncbi.nlm.nih.gov/core/pinger/pinger.js"> </script>
<script src="https://cdn.ncbi.nlm.nih.gov/pubmed/277eb475-38df-4990-a0ee-0080b04e86fc/CACHE/js/output.e3950ac8c6da.js"></script>
<script>
ncbi.awesome.articlePage.init({
baseSuggestionsUrl: "/suggestions/",
mathJaxUrl: "https://cdn.ncbi.nlm.nih.gov/pubmed/277eb475-38df-4990-a0ee-0080b04e86fc/mathjax/unpacked/MathJax.js?config=MML_CHTML",
clipboardAPIRoot: "/ajax/clipboard/",
clipboardNextPageUrl: "/clipboard-next-page/",
searchIdCookieName: "pm-sid",
searchFormSubmittedCookieName: "pm-sfs",
backToSearchCookieName: "pm-btsl",
jsCookieDomain: "pubmed.ncbi.nlm.nih.gov",
longTermPrefix: "longquery",
adjNavURLPath: "/22550198/adj-nav/",
adjNavSearchIdCookieName: "pm-adjnav-sid",
articlePageUrl: "/22550198/",
markJSUrl: "https://cdn.ncbi.nlm.nih.gov/pubmed/277eb475-38df-4990-a0ee-0080b04e86fc/mark.js/dist/jquery.mark.js",
termHighlightColor: "",
highlightedTokens: "",
citeFormatPreferenceCookieName: "pm-cf"
});
</script>
</body>
</html>