CDC-Data-2025/DQS_Health_US_Dataset_Footnote_Lookup.csv

1	FN_ID	FN_TEXT
2	FN0002	Body mass index (BMI) equals weight in kilograms divided by height in meters squared. In Health, United States, the National Health and Nutrition Examination Survey (NHANES) variable named Body Mass Index is rounded to one decimal place and is used to assign people to BMI categories. Estimates in this table may differ from other estimates where BMI is directly calculated using NHANES measured weight and height variables. See Appendix II, Body mass index (BMI), available from: https://www.cdc.gov/nchs/data/hus/hus19-appendix-508.pdf.
3	FN0005	High cholesterol is serum total cholesterol greater than or equal to 240 mg/dL (6.20 mmol/L), regardless of whether the respondent reported taking cholesterol-lowering medications. See Sources and Definitions, Cholesterol, available from: https://www.cdc.gov/nchs/hus/sources-definitions/cholesterol.htm.
4	FN0006	Hypercholesterolemia is measured serum total cholesterol greater than or equal to 240 mg/dL (6.20 mmol/L) or taking cholesterol-lowering medications. See Sources and Definitions, Cholesterol, available from: https://www.cdc.gov/nchs/hus/sources-definitions/cholesterol.htm.
5	FN0019	Age-adjusted rates are calculated using the year 2000 standard population with unrounded population numbers. See Sources and Definitions, Age adjustment, available from: https://www.cdc.gov/nchs/hus/sources-definitions/age-adjustment.htm.
6	FN0020	Age-adjusted rates are calculated using the year 2000 standard population. Starting with 2001 data, unrounded population numbers are used to calculate age-adjusted rates. Before 2001 data, age-adjusted rates were calculated using standard million proportions based on rounded population numbers. See Sources and Definitions, Age adjustment, available from: https://www.cdc.gov/nchs/hus/sources-definitions/age-adjustment.htm.
7	FN0026	Estimates are age adjusted to the year 2000 standard population using five age groups: 18-44, 45-54, 55-64, 65-74, and 75 and older. Estimates for adults ages 18-64 are age adjusted to three age groups: 18-44, 45-54, and 55-64. Estimates for adults age 65 and older are age adjusted to two age groups: 65-74 and 75 and older. Age-adjusted estimates in this table may differ from other age-adjusted estimates based on the same data and presented elsewhere if different age groups are used in the adjustment procedure. See Sources and Definitions, Age adjustment, available from: https://www.cdc.gov/nchs/hus/sources-definitions/age-adjustment.htm.
8	FN0027	Estimates are age adjusted to the year 2000 standard population using five age groups: 20–34 years, 35–44 years, 45–54 years, 55–64 years, and 65 years and older. Age-adjusted estimates in this table may differ from other age-adjusted estimates based on the same data and presented elsewhere if different age groups are used in the adjustment procedure. See Sources and Definitions, Age adjustment, available from: https://www.cdc.gov/nchs/hus/sources-definitions/age-adjustment.htm.
9	FN0032	Estimates are age adjusted to the year 2000 standard population using four age groups: 18 years and younger, 18–44 years, 45–64 years, and 65 years and older. Age-adjusted estimates in this data set may differ from other age-adjusted estimates based on the same data and presented elsewhere if different age groups are used in the adjustment procedure. See Sources and Definitions, Age adjustment, available from: https://www.cdc.gov/nchs/hus/sources-definitions/age-adjustment.htm.
10	FN0033	Estimates are age-adjusted to the year 2000 standard population using six age groups: younger than 18 years, 18-44 years, 45-54 years, 55-64 years, 65-74 years, and 75 years and older. See Sources and Definitions, Age adjustment, available from: https://www.cdc.gov/nchs/hus/sources-definitions/age-adjustment.htm.
11	FN0042	Estimates of education are for people aged 25-64. GED is General Educational Development high school equivalency diploma. See Sources and Definitions, Education, available from: https://www.cdc.gov/nchs/hus/sources-definitions/education.htm.
12	FN0046	Rates are age-adjusted to the year 2000 standard population using six age groups: younger than 18 years, 18-24 years, 25-44 years, 45-64 years, 65-74 years, and 75 years and older. See Sources and Definitions, Age adjustment, available from: https://www.cdc.gov/nchs/hus/sources-definitions/age-adjustment.htm.
13	FN0047	Data for the territories are shown by race and Hispanic origin only if race-specific data are available for all years in the 3-year period. Linked birth/infant death data are not available for American Samoa and Northern Marianas.
14	FN0048	Estimates for territories are shown by race and Hispanic-origin only if race-specific data are available for all years in the 3-year period.
15	FN0049	The race groups White, Black, American Indian and Alaska Native, Asian, and Native Hawaiian or Other Pacific Islander include people of Hispanic and non-Hispanic origin. People of Hispanic origin may be of any race. Starting with 2018 mortality data, race on death records is available based on the 1997 "Revisions to the Standards for the Classification of Federal Data on Race and Ethnicity" and presented as single-race estimates (only one race was reported on the death certificate). These estimates include separate estimates for non-Hispanic Asian and non-Hispanic Native Hawaiian or Other Pacific Islander categories. States transitioned from 1977 to 1997 standards during 2003-2017. During this period, race data were bridged to retain comparability with the 1977 standards, which included a combined non-Hispanic Asian or Pacific Islander category. Both single-race and bridged-race estimates are presented for 2018 and 2019. Single-race estimates for 2018 and beyond are not completely comparable with bridged-race estimates for earlier years, particularly for the smaller race categories. Starting with 2020 data, bridged-race estimates are no longer available. See Sources and Definitions, Hispanic origin; Race, available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
16	FN0051	Estimates by racial group should be used with caution because information on race was collected from medical records and race is imputed for records missing that information. In 2018, race data were missing and imputed for 29% of physician visits and 21% of emergency department visits. Information on the race imputation process used in each data year is available in the file documentation, available from: https://www.cdc.gov/nchs/ahcd/index.htm. Estimates for race in this table are for visits where only one race was recorded. Because of the small number of responses with more than one racial group recorded, estimates for visits with multiple races recorded are unreliable and not presented.
17	FN0054	People of Hispanic or Mexican origin may be of any race. Starting with 1999 data, race-specific estimates are tabulated according to the 1997 “Revisions to the Standards for the Classification of Federal Data on Race and Ethnicity” and are not strictly comparable with estimates for earlier years. The non-Hispanic race categories shown follow the 1997 standards. Starting with 1999 data, race-specific estimates are for people who reported only one racial group. For data before 1999, estimates are tabulated according to the 1977 standards. Estimates for single-race categories before 1999 include people who reported one race or, if they reported more than one race, identified one race as best representing their race. Data for Hispanic people are available starting with 2007-2008 and for Asian people starting with 2011-2012. See Sources and Definitions, Hispanic origin; Race, available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
18	FN0055	People of Hispanic origin may be of any race. See Appendix II, Hispanic origin, available from: https://www.cdc.gov/nchs/data/hus/hus17_appendix.pdf.
19	FN0063	The race and Hispanic-origin specific rates for 2015 exclude data from Rhode Island, which did not report race or Hispanic origin of mother on the fetal death report in that year. Rates for All mothers include data from Rhode Island.
20	FN0064	The race groups White, Black, American Indian and Alaska Native, Asian, Native Hawaiian or Other Pacific Islander, and two or more races include people of Hispanic and non-Hispanic origin. People of Hispanic origin may be of any race. Starting with 1999 data, race-specific estimates are tabulated according to the 1997 "Revisions to the Standards for the Classification of Federal Data on Race and Ethnicity" and are not strictly comparable with estimates for earlier years. The race-specific estimates are for people who reported only one racial group; the category two or more races includes people who reported more than one racial group. Starting with 2003 data, race responses of other race and unspecified multiple race are treated as missing, and then race is imputed if these were the only race responses. Most people with a race response of other race are of Hispanic origin. See Sources and Definitions, Hispanic origin; Race, available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
21	FN0067	The race groups White, Black, American Indian or Alaska Native, Asian or Pacific Islander, Asian, Native Hawaiian or Other Pacific Islander, and 2 or more races include people of Hispanic and non-Hispanic origin. People of Hispanic origin may be of any race. Starting with 1999 data, race-specific estimates are tabulated according to the 1997 "Revisions to the Standards for the Classification of Federal Data on Race and Ethnicity" and are not strictly comparable with estimates for earlier years. The race-specific estimates are for people who reported only one racial group; the category 2 or more races includes people who reported more than one racial group. These data include separate estimates for Asian and Native Hawaiian or Other Pacific Islander groups. For data before 1999, estimates are tabulated with four racial groups according to the 1977 standards and include a combined Asian or Pacific Islander category. Estimates for single-race categories before 1999 include people who reported one race or, if they reported more than one race, identified one race as best representing their race. Starting with 2003 data, race responses of other race and unspecified multiple race are treated as missing, and then race is imputed if these are the only race responses. Almost all people with a race response of other race are of Hispanic origin. See Sources and Definitions, Hispanic origin; Race, available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
22	FN0069	FPL is federal poverty level. Poverty level is based on the ratio of the family's income in the previous calendar year to the appropriate poverty threshold defined by the U.S. Census Bureau. Missing family income data are imputed for 1997 and beyond. See Sources and Definitions, Family income; Poverty, available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
23	FN0091	Insured includes private, Medicaid, and other insurance coverage. People who reported both Medicaid and private coverage are classified as having private coverage. Starting with 1997 data, state-sponsored health plan coverage is included as Medicaid coverage. Starting with 1999 data, coverage by the Children's Health Insurance Program (CHIP) is included as Medicaid coverage. In addition to private and Medicaid, the insured category includes military plans, other government-sponsored health plans, and Medicare. People not covered by private insurance, Medicaid, CHIP, state-sponsored or other government-sponsored health plans (starting in 1997), Medicare, or military plans are considered to have no health insurance coverage. People with only Indian Health Service coverage are considered to have no health insurance coverage. See Sources and Definitions, Health insurance coverage, available from: https://www.cdc.gov/nchs/hus/sources-definitions/health-insurance-coverage.htm.
24	FN0102	Functional limitation is defined by the reported level of difficulty in six domains of functioning: seeing (even if wearing glasses), hearing (even if wearing hearing aids), mobility (walking or climbing stairs), communication (understanding or being understood by others), cognition (remembering or concentrating), and self-care (such as washing all over or dressing). Respondents with answers to one or more of the six questions are included in one of three mutually exclusive categories. Adults who respond "a lot of difficulty" or "cannot do at all/unable to do" to at least one question are classified in the "a lot of difficulty or cannot do at all" category. Of the remaining respondents, adults who respond "some difficulty" to at least one question are classified in the "some difficulty" category, and adults who respond "no difficulty" to all questions are classified in the "no difficulty" category. Adults who respond "don't know" or "refused" to all six questions are excluded. During 2010-2019, 0%-8% of respondents were missing data and excluded. See Sources and Definitions, Functional limitation, available from: https://www.cdc.gov/nchs/hus/sources-definitions/functional-limitation.htm.
25	FN0114	Estimates are for people aged 2 and older. Nonreceipt of needed dental care due to cost is based on responses to questions about whether there was any time during the past 12 months when the respondent needed dental care but did not get it because of the cost. See Sources and Definitions, Unmet need, available from: https://www.cdc.gov/nchs/hus/sources-definitions/unmet-need.htm.
26	FN0115	Nonreceipt of needed prescription drugs due to cost is based on responses to questions about whether there was any time during the past 12 months when the respondent needed prescription medicine but did not get it because of the cost. See Sources and Definitions, Unmet need, available from: https://www.cdc.gov/nchs/hus/sources-definitions/unmet-need.htm.
27	FN0116	Delay or nonreceipt of needed medical care due to cost is based on responses to questions about whether there was any time during the past 12 months when the respondent needed medical care but delayed or did not get it because of the cost. See Sources and Definitions, Unmet need, available from: https://www.cdc.gov/nchs/hus/sources-definitions/unmet-need.htm.
28	FN0124	Community hospitals are nonfederal short-term general and special hospitals whose facilities and services are available to the public. The types of facilities included in this category have changed over time. See Sources and Definitions, Hospital, available from: https://www.cdc.gov/nchs/hus/sources-definitions/hospital.htm.
29	FN0131	Outpatient visits include visits to the emergency department, outpatient department, referred visits (pharmacy, EKG, radiology), and outpatient surgery. See Sources and Definitions, Outpatient visit, available from: https://www.cdc.gov/nchs/hus/sources-definitions/outpatient-visit.htm.
30	FN0143	Before 1995, data are shown only for states with a Hispanic-origin item on their birth certificates. See Sources and Definitions, Hispanic origin, available from: https://www.cdc.gov/nchs/hus/sources-definitions/hispanic-origin.htm.
31	FN0145	Before 1997 data, estimates for Hispanic origin and race do not include data from states that did not report Hispanic origin on the death certificate. See Sources and Definitions, Hispanic origin, available from: https://www.cdc.gov/nchs/hus/sources-definitions/hispanic-origin.htm.
32	FN0156	Drug overdose deaths involving any opioid includes deaths with an underlying cause of drug overdose and an opioid mentioned in ICD-10 multiple causes of death. The Any opioid category is defined by multiple cause-of-death codes T40.0-T40.4 and T40.6.
33	FN0157	Deaths from drug overdose is coded using underlying cause of death according to the 10th revision of the International Classification of Diseases (ICD-10). See Sources and Definitions, Cause of death; International Classification of Diseases (ICD), available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm. Drug overdose deaths include those resulting from accidental or intentional overdose of a drug, being given the wrong drug, taking the wrong drug in error, taking a drug inadvertently, or other misuses of drugs. These deaths are from all manners and intents, including unintentional, suicide, homicide, legal intervention, operations of war, and undetermined intent. The All drug category is defined by cause-of-death codes X40-X44, X60-X64, X85, and Y10-Y14.
34	FN0160	Starting with 1999 data, cause of death is coded according to ICD-10. See Sources and Definitions, Cause of death; Comparability ratio; International Classification of Diseases (ICD), available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
35	FN0164	Underlying cause of death was coded according to the sixth revision of the International Classification of Diseases (ICD-6) in 1950, seventh revision in 1960, eighth revision in 1970, and ninth revision in 1980-1998. See Sources and Definitions, Cause of death; International Classification of Diseases (ICD), available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
36	FN0171	Binge drinking is defined as five or more alcoholic drinks in a row at least once in the previous 2-week period. See Sources and Definitions, Binge alcohol use, available from: https://www.cdc.gov/nchs/hus/sources-definitions/binge-alcohol-use.htm.
37	FN0173	In 1993, the alcohol question was changed to indicate that a drink meant more than a few sips. Data for 1993 are based on a half sample. In 2022, a survey change that removed a skip pattern resulted in higher levels of inconsistent responses for alcohol use among 8th and 10th grade students (that is, students were more likely to report lifetime alcohol use early in the survey but then later report that they had never used alcohol). These inconsistent responders were coded as missing in 2022. The skip pattern will be reintroduced into the survey in 2023. See Sources and Definitions, Alcohol consumption, available from: https://www.cdc.gov/nchs/hus/sources-definitions/alcohol-consumption.htm.
38	FN0183	Total includes all other races not shown separately and those with unknown sex, unknown marital status, unknown disability (functional limitation) status, and, in 1984 and 1989, unknown poverty level.
39	FN0187	Total includes people of all other races not shown separately and those with unknown health insurance status, unknown education level, and unknown sex, and unknown disability (functional limitation) status.
40	FN0191	Rates for 1950 and 1960 include deaths of people who were not residents of the 50 states or the District of Columbia. In 1950, deaths of people in Alaska and Hawaii are excluded because these states did not receive statehood until 1959.
41	FN0197	American Indian and Alaska Native and Asian or Pacific Islander groups include people of Hispanic origin.
42	FN0201	Total includes people of all races and Hispanic origins, not just those shown separately.
43	FN0203	All mechanisms includes unintentional injury-related visits with mechanisms of injury not shown.
44	FN0208	MSA is metropolitan statistical area. Starting with 2016 data, MSA status is determined using 2010 census data and the 2010 standards for defining MSAs. For more information, including the definition applied before 2016, see Sources and Definitions, Metropolitan statistical area (MSA), available from: https://www.cdc.gov/nchs/hus/sources-definitions/msa.htm.
45	FN0209	Rates for the United States exclude data for American Samoa, Guam, Northern Marianas, Puerto Rico, and Virgin Islands.
46	FN0212	Excludes live births with unknown birthweight. See Appendix II, Birthweight, available from: https://www.cdc.gov/nchs/data/hus/hus17_appendix.pdf.
47	FN0213	Estimates for states are shown by Hispanic origin only if Hispanic-origin data are available for all years in the 3-year period.
48	FN0218	Rates for 1999-2004 exclude data from Oklahoma, which did not report Hispanic origin on the fetal death report in those years.
49	FN0219	Rates for White and Black are substituted for White non-Hispanic and Black non-Hispanic for Louisiana for 1989, Oklahoma for 1989-1990, and New Hampshire for 1989-1991.
50	FN0222	Younger than 1 year of age.
51	FN0227	In 1950, the rate for Black males aged 75-84 years includes ages 75 and older.
52	FN0230	Infant deaths are younger than 1 year; neonatal deaths are younger than 28 days; and postneonatal deaths are 28 days to 364 days. See Sources and Definitions, Infant death; Rate: Death and related rates, available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
53	FN0239	Fetal death rates are the number of fetal deaths at 20 weeks of gestation or more per 1,000 live births and fetal deaths. See Sources and Definitions, Fetal death; Rate: Death and related rates, available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
54	FN0240	Late fetal death rates are the number of fetal deaths at 28 weeks of gestation or more (late fetal deaths) per 1,000 live births and late fetal deaths. See Sources and Definitions, Fetal death; Rate: Death and related rates, available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
55	FN0241	Perinatal death rates are the number of late fetal deaths and infant deaths within 7 days of birth per 1,000 live births and late fetal deaths. See Sources and Definitions, Fetal death; Rate: Death and related rates, available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
56	FN0247	Rates for 2003 and beyond are based on the period file using weighted data. See Appendix I, National Vital Statistics System (NVSS), Linked Birth/Infant Death Data Set, available from: https://www.cdc.gov/nchs/data/hus/hus17_appendix.pdf.
57	FN0249	Rates for 1989-1991 are based on unweighted birth cohort data.
58	FN0255	Drug overdose deaths involving natural and semisynthetic opioids includes deaths with an underlying cause of drug overdose and a natural or semisynthetic opioid (such as codeine, oxycodone, and morphine) mentioned in the ICD-10 multiple cause of death. The Natural or semisynthetic opioid category is defined by multiple cause-of-death code T40.2.
59	FN0256	Drug overdose deaths involving synthetic opioids other than methadone include deaths with an underlying cause of drug overdose and synthetic opioids other than methadone mentioned in the ICD-10 multiple causes of death. The Synthetic opioids other than methadone category includes fentanyl, tramadol, and propoxyphene (removed from the market in 2010) and is defined by multiple cause-of-death code T40.4. In 2014, a sharp increase in deaths involving synthetic opioids other than methadone coincided with law enforcement reports of increased availability of illicitly manufactured or nonpharmaceutical fentanyl. Illicitly manufactured fentanyl cannot be distinguished from pharmaceutical fentanyl in death certificate data. For more information, see Centers for Disease Control and Prevention. Health advisory: Increases in fentanyl drug confiscations and fentanyl-related overdose fatalities. CDC Health Action Network. 2015 Oct;(384) and Rudd RA, Aleshire N, Zibbell JE, Gladden RM. Increases in Drug and Opioid Overdose Deaths–United States, 2000-2014. MMWR Morb Mortal Wkly Rep. 2016 Jan;64(50-51):1378-82. PMID: 26720857. DOI:https://doi.org/10.15585/mmwr.mm6450a3.
60	FN0257	Drug overdose deaths involving heroin include deaths with an underlying cause of drug overdose and heroin mentioned in the ICD-10 multiple causes of death. The Heroin category is defined by multiple cause-of-death code T40.1. Metabolic breakdown of heroin into morphine in the body can make it difficult to distinguish between deaths from heroin and those from morphine based on information on the death certificate. Some deaths reported to involve morphine could be deaths from heroin, which may result in an undercount of heroin-related deaths. For more information, see Hedegaard H, Chen LH, Warner M. Drug-poisoning deaths involving heroin: United States, 2000-2013. NCHS Data Brief. 2015 Mar(190):1-8. PMID: 25932890.
61	FN0261	Beginning in quarter 3 of the 2004 NHIS, people younger than 65 years with no reported coverage are asked explicitly about Medicaid coverage. Estimates are calculated with the additional information starting with 2005 data.
62	FN0262	Estimates of percent of poverty level are calculated by dividing family income by the U.S. Department of Health and Human Services’ poverty guideline specific to family size, as well as the appropriate year and state. People with unknown percent of poverty level are excluded (11% in 2017–March 2020) from the hypertension estimates in this data set. See Sources and Definitions, Family income; Poverty, available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
63	FN0265	Estimates for 2000-2002 are calculated using 2000-based sample weights and may differ from estimates that use 1990-based sample weights for 2000-2002 estimates.
64	FN0266	FPL is federal poverty level. Poverty level is based on the ratio of the family's income in the previous calendar year to the appropriate poverty threshold defined by the U.S. Census Bureau. Poverty level was unknown for 10%-11% of people younger than 65 years in 1984 and 1989. Missing family income data are imputed for 1990 and beyond. See Sources and Definitions, Family income; Poverty, available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
65	FN0267	Classification of intent and mechanism of injury is based on the first-listed diagnosis code and the external cause-of-injury matrix. Intentional injuries include self-inflicted injuries and assaults. See Sources and Definitions, External cause of injury; Injury; Injury-related visit, available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
66	FN0268	Estimates for total, sex, and sex and age groups include all injury-related visits not shown separately in table, including those with undetermined intent and insufficient information to code cause of injury.
67	FN0269	Persons of Hispanic origin may be of any race. See Appendix II, Hispanic origin, available from: https://www.cdc.gov/nchs/data/hus/hus17_appendix.pdf.
68	FN0270	Employment is the number of filled positions. This data set includes both full- and part-time wage and salary positions. Estimates do not include the self-employed, owners and partners in unincorporated firms, household workers, or unpaid family workers. Estimates are rounded to the nearest 10.
69	FN0271	Mean hourly wage rate for an occupation is the total wages that all workers in the occupation earn in an hour divided by the total employment in the occupation. For more information, see: https://www.bls.gov/oes/2022/may/oes_tec.htm.
70	FN0272	Starting with 2012 data, the Radiologic technologists and technicians occupation category was split into two occupations as part of the 2010 Standard Occupational Classification (SOC) revision: Radiologic technologists (29-2034) and Magnetic resonance imaging technologists (29-2035). As a result, data before 2012 included radiologic technologists as well as magnetic resonance imaging technologists and are not comparable with 2012 and beyond.
71	FN0273	Starting with 2012 data, the Registered nurses occupation category was split into four occupations as part of the 2010 Standard Occupational Classification (SOC) revision: Registered nurses (29-1141), plus three advanced practice nursing occupations: Nurse anesthetists (29-1151), Nurse midwives (29-1161), and Nurse practitioners (29-1171). As a result, data before 2012 included registered nurses as well as nurse anesthetists, nurse midwives, and nurse practitioners and are not comparable with data from 2012 and beyond.
72	FN0274	Starting with 2012 data, the Nursing aides, orderlies, and attendants occupation category (31-1012) was split into two occupations as part of the 2010 Standard Occupational Classification (SOC) revision: Nursing assistants (31-1014) and Orderlies (31-1015). As a result, data before 2012 included nursing assistants as well as orderlies and are not comparable with data from 2012 and beyond.
73	FN0336	Average length of stay is the number of inpatient days divided by the number of admissions. See Sources and Definitions, Average length of stay, available from: https://www.cdc.gov/nchs/hus/sources-definitions/average-length-of-stay.htm.
74	FN0338	Total surgeries is a measure of patients with at least one surgical procedure. People with multiple surgical procedures during the same outpatient visit or inpatient stay are counted only once. See Sources and Definitions, Outpatient surgery, available from: https://www.cdc.gov/nchs/hus/sources-definitions/outpatient-surgery.htm.
75	FN0443	The race groups White, Black, American Indian or Alaska Native, Asian, Native Hawaiian or Other Pacific Islander, and 2 or more races include people of Hispanic and non-Hispanic origin. People of Hispanic origin may be of any race. Starting with 1999 data, race-specific estimates are tabulated according to the 1997 "Revisions to the Standards for the Classification of Federal Data on Race and Ethnicity" and are not strictly comparable with estimates for earlier years. The five single- and multiple-race categories shown follow the 1997 standards. The race-specific estimates are for people who reported only one racial group; the category 2 or more races includes people who reported more than one racial group. Starting with 2003 data, race responses of other race and unspecified multiple race are treated as missing, and then race is imputed if these were the only race responses. Almost all people with a race response of other race are of Hispanic origin. See Sources and Definitions, Hispanic origin; Race, available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
76	FN0455	Drug overdose deaths involving methadone includes deaths with an underlying cause of drug overdose and methadone mentioned in ICD-10 multiple causes of death. The Methadone category is defined by multiple cause-of-death code T40.3.
77	FN0461	Rates for races other than White and Black people should be interpreted with caution because of inconsistencies in reporting Hispanic origin or race on the death certificate (death rate numerators) compared with population figures (death rate denominators). The net effect of misclassification for these race groups is an underestimation of deaths and death rates. For a detailed discussion of sources of bias in death rates by race and Hispanic origin, see Sources and Definitions, Race, available from: https://www.cdc.gov/nchs/hus/sources-definitions/race.html.
78	FN0465	Race and Hispanic origin refer to mother's race and Hispanic origin. The race groups White, Black, American Indian and Alaska Native, Asian, and Native Hawaiian or Other Pacific Islander include people of Hispanic and non-Hispanic origin. People of Hispanic origin may be of any race. Starting with 2017 linked birth/infant death data, race on birth records is available based on the 1997 “Revisions to the Standards for the Classification of Federal Data on Race and Ethnicity” and presented as single-race estimates (only one race was reported on the birth certificate). These estimates include separate estimates for Asian non-Hispanic and Native Hawaiian or Other Pacific Islander non-Hispanic categories. States transitioned from 1977 to 1997 Office of Management and Budget standards during 2003-2016. For this period, race data were bridged to retain comparability with the 1977 Office of Management and Budget standards, which included a combined Asian or Pacific Islander non-Hispanic category. Both single- and bridged-race estimates are presented for 2017-2019. Single-race estimates for 2017 and beyond are not completely comparable with bridged-race estimates for earlier years, particularly for the smaller race categories. Starting with 2020 data, bridged-race estimates are no longer available. See Sources and Definitions, Hispanic origin; Race, available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
79	FN0466	See Sources and Definitions, Bed, health facility, available from: https://www.cdc.gov/nchs/hus/sources-definitions/bed-health-facility.htm.
80	FN0467	See Sources and Definitions, Average annual rate of change (percent change), available from: https://www.cdc.gov/nchs/hus/sources-definitions/average-annual-rate-of-change.htm.
81	FN0468	Race and Hispanic origin refer to mother's race and Hispanic origin. The race groups White, Black, American Indian and Alaska Native, Asian, and Native Hawaiian or Other Pacific Islander include people of Hispanic and non-Hispanic origin. People of Hispanic origin may be of any race. Starting with 2018 fetal death data, race on fetal death records is available based on the 1997 “Revisions to the Standards for the Classification of Federal Data on Race and Ethnicity” and presented as single-race estimates (only one race was reported on the report of fetal death). These estimates include separate estimates for Asian non-Hispanic and Native Hawaiian or Other Pacific Islander non-Hispanic categories. States transitioned from 1977 to 1997 Office of Management and Budget standards during 2003-2017. For this period, race data were bridged to retain comparability with the 1977 Office of Management and Budget standards, which included a combined Asian or Pacific Islander non-Hispanic category. Both single- and bridged-race estimates are presented for 2018 and 2019. Single-race estimates for 2018 and beyond are not completely comparable with bridged-race estimates for earlier years, particularly for the smaller race categories. Starting with 2020 data, bridged-race estimates are no longer available. See Sources and Definitions, Hispanic origin; Race, available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
82	FN0471	FPL is federal poverty level. Estimates of poverty level are calculated by dividing family income by the U.S. Department of Health and Human Services' poverty guideline specific to family size, as well as the appropriate year and state. People with unknown poverty level are excluded (9% in 2015-2018) from the childhood obesity estimates in this file. See Appendix II, Family income; Poverty, available from: https://www.cdc.gov/nchs/data/hus/hus19-appendix-508.pdf.
83	FN0506	Data for physician visits are not available in 2017.
84	FN0514	Rates for 1983, 1985, 1990, 1996, and 1997 are based on unweighted birth cohort data.
85	FN0515	Rates for 1995 and 1998 and beyond are based on the period file using weighted data. See Sources and Definitions, National Vital Statistics System (NVSS), Linked Birth/Infant Death Data Set, available from: https://www.cdc.gov/nchs/hus/sources-definitions/nvss.htm.
86	FN0517	Estimates for total include all other races not shown separately and those with unknown sex.
87	FN0591	In the geographic classification of the U.S. population, states are grouped into four regions used by the U.S. Census Bureau. Northeast: Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, Connecticut, New York, New Jersey, and Pennsylvania. Midwest: Ohio, Indiana, Illinois, Michigan, Wisconsin, Minnesota, Iowa, Missouri, North Dakota, South Dakota, Nebraska, and Kansas. South: Delaware, Maryland, District of Columbia, Virginia, West Virginia, North Carolina, South Carolina, Georgia, Florida, Kentucky, Tennessee, Alabama, Mississippi, Arkansas, Louisiana, Oklahoma, and Texas. West: Montana, Idaho, Wyoming, Colorado, New Mexico, Arizona, Utah, Nevada, Washington, Oregon, California, Alaska, and Hawaii. See Sources and Definitions, Geographic division or region, available from: https://www.cdc.gov/nchs/hus/sources-definitions/geographic-region.htm.
88	FN0592	Marital status is the status at the time of interview. "Married" includes all people who identify themselves as married and who are not separated from their spouses. Married people living apart because of circumstances of their employment are considered married. People may identify themselves as married regardless of the legal status of the marriage or sex of the spouse. "Widowed" includes people who have lost their spouse due to death. "Divorced or separated" includes people who are legally separated from their spouse or living apart for reasons of marital discord, and those who are divorced. "Never married" includes people who were never married (or who were married and then had that marriage legally annulled). "Living with partner" includes unmarried persons regardless of sex who are living together as a couple, but do not identify themselves as married. Before the 2019 NHIS, marital status is asked of, or about, all people age 14 years and older. From 2019 onward, marital status is asked of sample adults age 18 and older. See Sources and Definitions, Marital status, available from: https://www.cdc.gov/nchs/hus/sources-definitions/marital-status.htm.
89	FN0593	FPL is federal poverty level. Estimates of poverty level are calculated by dividing family income by the U.S. Department of Health and Human Services' poverty guideline specific to family size, as well as the appropriate year and state. People with unknown percent of poverty level are excluded (9% in 2015-2018). See Appendix II, Family income; Poverty, available from: https://www.cdc.gov/nchs/data/hus/hus19-appendix-508.pdf.
90	FN0594	Estimates of percent of poverty level are calculated by dividing family income by the U.S. Department of Health and Human Services’ poverty guideline specific to family size, as well as the appropriate year and state. People with unknown percent of poverty level are excluded (11% in 2017–March 2020) from the cholesterol estimates in this dataset. See Sources and Definitions, Family income; Poverty, available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
91	FN0595	Rates for 1996 and 1997 are based on unweighted birth cohort data.
92	FN0596	In 2017, questions on vaping were revised to include separate questions about vaping nicotine, marijuana, and just flavoring. See Sources and Definitions, Tobacco use, available from: https://www.cdc.gov/nchs/hus/sources-definitions/tobacco-use.htm.
93	FN0597	In March 2020, in-school data collection was stopped because of the COVID-19 pandemic. This resulted in a sample size about one-quarter the size of a typical data collection. As a result, data by sex and race are not available for 2020. However, detailed analysis supports that the 2020 study results are nationally representative. See Sources and Definitions, Monitoring the Future (MTF), available from: https://www.cdc.gov/nchs/hus/sources-definitions/mtf.htm.
94	FN0598	Starting in 2014, a revised question on the use of MDMA (Ecstasy) including "Molly," a nickname for MDMA, was added to the questionnaire for each grade. Data reported for 2014 and beyond are only for the revised question that includes "Molly." See Sources and Definitions, Illicit drug use, available from: https://www.cdc.gov/nchs/hus/sources-definitions/illicit-drug-use.htm.
95	FN0599	Starting with 2017 data, only the broad occupation Clinical laboratory technologists and technicians (29-2010) data are available, not the two detailed occupations separately (Medical laboratory technicians [29-2011] and Medical laboratory technologists [29-2012]). The clinical laboratory technologists and technicians data series first became available in 2012. For more information, see: https://www.bls.gov/oes/notices/2017/changes_2017.htm.
96	FN0600	Starting with 2019 data, the Medical records and health information technicians (29-2071) data are not available. As part of the 2018 Standard Occupational Classification (SOC) revision, this occupation was split into two new occupations, Medical records specialists (29-2072) and Health information technologists and medical registrars (29-9021), for which data are available beginning in 2021. Data for Medical records specialists (29-2072) are presented in this data set and are not comparable with 2000-2018 data for Medical records and health information technicians.
97	FN0601	Starting with 2019 data, the Personal care aides occupation category (31-1122) was moved from the Personal care and service occupations major group to the Healthcare support group as part of the 2018 Standard Occupational Classification (SOC) revision. As of May 2019, data are available only for the broad occupation Home health and personal care aides (31-1120), which contains both home health aides (31-1121) and personal care aides (31-1122) and is not directly comparable to earlier data for home health aides alone.
98	FN9998	Estimates are for students using the substance in the past 30 days.
99	NA0002	Category not applicable. This is represented by a ellipsis flag (...).
100	NA0003	Quantity zero. This is represented by a single dash flag (-).
101	NA0004	Data not available. This is represented by a triple dash flag (- - -).
102	NA0005	Some estimates are considered unreliable; rates based on fewer than 20 deaths in the numerator are not shown. This is represented with a single asterisk flag (*).
103	NA0006	The reliability of estimates determines if and how they are shown. Estimates flagged with an asterisk may be unreliable and should be interpreted with caution. Estimates not shown do not meet reliability criteria. Starting with 2013–2016 data, the reliability of survey percentages is assessed using multistep data presentation standards for proportions from the National Center for Health Statistics. For data before 2013–2016, the reliability of survey percentages was assessed using relative standard errors. For more information, see Sources and Definitions, Relative standard error (RSE); Statistical reliability of estimates, available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
104	NA0007	The reliability of estimates determines if and how they are shown. Estimates flagged with an asterisk may be unreliable and should be interpreted with caution. Estimates not shown do not meet reliability criteria. Starting with 2016 data, the reliability of survey percentages is assessed using multistep data presentation standards for proportions from the National Center for Health Statistics. For data before 2016, the reliability of survey percentages was assessed using relative standard errors. For more information, see Sources and Definitions, Data presentation standards for proportions; Relative standard error (RSE), available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
105	NA0008	Some estimates are considered unreliable. Data flagged with an asterisk have a relative standard error (RSE) of 20%-30%. Data not shown have an RSE greater than 30%. For 2017-2018 data, estimates based on fewer than 30 observations also are not shown.
106	NA0009	Some estimates are considered unreliable: percentages based on fewer than 20 births are not shown. This is represented with a single asterisk flag (*).
107	NA0017	Quantity more than zero but less than 0.05. This is represented by a tilde flag (~).
108	NA0038	The reliability of estimates determines if and how they are shown. Estimates flagged with an asterisk may be unreliable and should be interpreted with caution. Estimates not shown do not meet reliability criteria. Starting with the 2013-2014 cycle of data, the reliability of survey percentages is assessed using multistep data presentation standards for proportions from the National Center for Health Statistics. For data before the 2013-2014 cycle, the reliability of survey percentages was assessed using relative standard errors. For more information, see Appendix II, Data presentation standards for proportions; Relative standard error (RSE), available from: https://www.cdc.gov/nchs/data/hus/hus19-appendix-508.pdf.
109	NT0001	Drug overdose deaths may involve multiple drugs. Deaths involving multiple drugs (e.g., heroin and oxycodone) are included in the death rate for natural or semisynthetic opioids and the death rate for heroin. For more information on the type of drugs commonly involved in drug overdose deaths, in addition to the use of literal text from the death certificate to enhance mortality statistics, see Hedegaard H, Bastian BA, Trinidad JP, Spencer M, Warner M. Drugs most frequently involved in drug overdose deaths: United States, 2011-2016. Natl Vital Stat Rep. 2018 Dec;67(9):1-14. PMID: 30707673. In 1999-2021, 5%-25% of drug overdose deaths did not include specific information on the death certificate about the type of drug involved. For more information, see Spencer MR, Minino AM, Warner M. Drug overdose deaths in the United States, 2001-2021. NCHS Data Brief. 2022 Dec(457):1-8. PMID: 36598401. Rates for 2011 and beyond are computed using 2010-based postcensal estimates. Rates for 2010 are computed based on 2010 bridged-race April 1 census counts. Rates for 2001-2009 are computed using intercensal population estimates based on the 2000 and 2010 censuses. Rates for 2000 are computed based on 2000 bridged-race April 1 census counts. Rates for 1999 are computed using intercensal population estimates based on the 1990 and 2000 censuses. See Sources and Definitions, Population Census and Population Estimates, available from: https://www.cdc.gov/nchs/hus/sources-definitions/census-population.htm. Age groups are selected to minimize the presentation of unstable age-specific death rates based on small numbers of deaths and for consistency among comparison groups.
110	NT0002	Suicide is defined by cause-of-death codes *U03, X60-X84, and Y87.0. Suicide rates for all ages include the small number of suicides among children aged 5-9 years. Rates for 2011 and beyond are computed using 2010-based postcensal estimates. Rates for 2010 are computed based on 2010 bridged-race April 1 census counts. Rates for 2001-2009 are computed using intercensal population estimates based on the 2000 and 2010 censuses. Rates for 2000 are computed based on 2000 bridged-race April 1 census counts. Rates for 1999 are computed using intercensal population estimates based on the 1990 and 2000 censuses. See Sources and Definitions, Population Census and Population Estimates, available from: https://www.cdc.gov/nchs/hus/sources-definitions/census-population.htm. Estimates for 2001 included September 11-related deaths for which death certificates were filed as of October 24, 2002. See Sources and Definitions, Cause of death, for terrorism-related ICD-10 codes available from: https://www.cdc.gov/nchs/hus/sources-definitions/cause-of-death.htm. Age groups are selected to minimize the presentation of unstable age-specific death rates based on small numbers of deaths and for consistency among comparison groups.
111	NT0003	National linked files do not exist for 1992-1994.
112	NT0004	Percentages do not sum to 100 because the percentage of people with BMI less than 18.5 is not shown. Additionally, the percentage of people with obesity is embedded in the percent overweight or obese and can be further partitioned into Grades 1, 2, and 3 obesity. Age of the participant (in years) is at the time of screening. Height is measured without shoes.
113	NT0009	Hypertension is defined as having measured high blood pressure or taking high blood pressure medication. High blood pressure is defined as having measured systolic pressure of at least 130 mm Hg or diastolic pressure of at least 80 mm Hg. Those with high blood pressure may also be taking prescribed medicine for high blood pressure. Those reporting taking high blood pressure medication may not have measured high blood pressure but are still classified as having hypertension. Percentages are based on the average of blood pressure measurements taken. In 2017–March 2020, 91% of participants had three systolic or diastolic blood pressure readings. Estimates exclude pregnant women. See Sources and Definitions, Hypertension, available from: https://www.cdc.gov/nchs/hus/sources-definitions/hypertension.htm. The National Health and Nutrition Examination Survey (NHANES) program suspended field operations in March 2020 due to the COVID-19 pandemic. As a result, data collection for the 2019–2020 cycle was not completed. Therefore, data collected from 2019–March 2020 were combined with data from the 2017–2018 cycle to create a 2017–March 2020 prepandemic file. This file covers 3.2 years of data collection. For more information, see: https://www.cdc.gov/nchs/products/series/series02.htm.
114	NT0012	Prescription medication use is based on a question about whether respondents had taken a prescription medication (not including prescription dietary supplements) in the past 30 days. For participants younger than age 16 years, a parent or other proxy provided the information. See Sources and Definitions, Drug, available from: https://www.cdc.gov/nchs/hus/sources-definitions/drug.htm. The National Health and Nutrition Examination Survey (NHANES) program suspended field operations in March 2020 due to the COVID-19 pandemic. As a result, data collection for the 2019–2020 cycle was not completed. Therefore, data collected from 2019–March 2020 were combined with data from the 2017–2018 cycle to create a 2017–March 2020 prepandemic file. This file covers 3.2 years of data collection. For more information, see: https://www.cdc.gov/nchs/products/series/series02.htm.
115	NT0016	Infant mortality rates are based on infant deaths younger than 1 year of age. Starting with 2003 data, some states reported multiple-race data. The multiple-race data for these states were bridged to the single-race categories of the 1977 Office of Management and Budget standards, for comparability with other states. See Appendix II, Race, available from https://www.cdc.gov/nchs/data/hus/hus17_appendix.pdf. National linked files do not exist for 1992-1994.
116	NT0017	Rates are calculated using estimates of the civilian noninstitutionalized population of the United States. Rates for 2011 data and beyond are computed using 2010-based postcensal population estimates. Rates for 2001-2010 were computed using 2000-based postcensal population estimates. Rates for 2000 were computed using 1990-based postcensal population estimates. Rates using the civilian noninstitutionalized population may be overestimated to the extent that visits by institutionalized people are counted in the numerator (for example, hospital emergency department visits by nursing home residents), but institutionalized people are omitted from the denominator (civilian noninstitutionalized population). In 2012-2015 and 2018, data for physician offices excluded visits to community health centers; in 2006-2011, data for all places and physician offices included visits to community health centers (2%-3% of visits to physician offices in 2006-2011 were to community health centers). Before 2006, visits to community health centers were not included in the survey. See Sources and Definitions, Emergency department; Emergency department or emergency room visit; Office visit, available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
117	NT0018	Medicaid coverage includes people who had any of the following at the time of interview: Medicaid, other public assistance (through 1996), state-sponsored health plan (starting in 1997), or Children's Health Insurance Program [(CHIP) starting in 1999]. It includes those who also had another type of coverage in addition to one of these. In 2019, 18.4% of people younger than 65 years reported being covered by Medicaid, 0.9% by state-sponsored health plans, and 0.9% by CHIP. Estimates may not sum to total because of rounding. The number of people with Medicaid coverage is calculated by multiplying the percentage with Medicaid coverage by the number of people younger than 65 years in the civilian noninstitutionalized U.S. population, as determined from the poststratification Census control total for each survey year. Percentages of people with Medicaid coverage are calculated with unknown values excluded from denominators. See Sources and Definitions, Health insurance coverage; Medicaid, available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm. Estimates in this table may differ slightly from other estimates based on the same data and presented elsewhere if different methodologies were used (for example, how missing data were handled).
118	NT0019	An emergency department visit is based on the diagnosis code. Due to a change in national medical data coding standards in 2015, from the International Classification of Diseases (ICD), Ninth Revision, Clinical Modification (ICD-9-CM) to the ICD-10-CM, the definition for injuries and injury subcategories changed for the 2016 reporting period and beyond. Results from 2016 and subsequent years should not be compared with previous reporting periods. Any observed changes in trends across this transition period should not be considered. For more information, see Sources and Definitions, Injury; Injury-related visit; International Classification of Diseases, Clinical Modification (ICD-CM), available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm. Rates are calculated using U.S. Census Bureau estimates of the civilian population of the United States, including institutionalized people. Rates for 2005-2010 were computed using 2000-based postcensal population estimates. Rates for 2011 and beyond are computed using 2010-based postcensal population estimates.
119	NT0020	Race and Hispanic origin refer to mother's race and Hispanic origin. Estimates are based on single-race categories; multiple-race data were bridged to single-race categories as needed. For information on low birthweight live births by state, see Table I-21 in Martin JA, Hamilton BE, Osterman MJK, Driscoll AK, Drake P. Births: Final data for 2016. Natl Vital Stat Rep. 2018 Jan;67(9):1-55. PMID: 29775434. Starting with 2003 data, some states and territories reported multiple-race data. The multiple-race data for these areas were bridged to the single-race categories of the 1977 Office of Management and Budget standards, for comparability with other states. As of January 1, 2016, all states and reporting areas (other than American Samoa) had adopted the 2003 U.S. Standard Certificate of Live Birth. Bridged single-race categories are still presented in Health, United States to permit trend comparisons. See Appendix II, Race, available from: https://www.cdc.gov/nchs/data/hus/hus17_appendix.pdf.
120	NT0021	Data include professionally active dentists only. Professionally active dentists in this table are those who are listed in the American Dental Association (ADA) masterfile as licensed, not retired, living in the 50 states or District of Columbia, and having a primary occupation of: private practice (full- or part-time); dental school or faculty staff member; armed forces; other federal service (e.g., Veterans Affairs or Public Health Service); state or local government employee; hospital staff dentist; graduate student, intern, or resident; or other health or dental organization staff member. Data exclude dentists in U.S territories or U.S. armed forces overseas. U.S. totals include dentists with unknown state of practice not shown separately and may include missing data. Data on the number of dentists per 100,000 resident population for 2011–2021 are calculated using the 2020 census. Data for 2010 are calculated using the 2010 census, and data for 2001–2009 are calculated using intercensal estimates based on the 2000 and 2010 censuses.
121	NT0022	The estimates exclude occupations such as dentists, physicians, and chiropractors, which have a large percentage of workers who are self-employed. Challenges in using Occupational Employment and Wage Statistics data as a time series include changes in the occupational, industrial, and geographical classification systems; changes in the way data are collected; changes in the survey reference period; and changes in mean wage estimation methodology, as well as permanent features of the methodology. See Sources and Definitions, Occupational Employment and Wage Statistics (OEWS), at: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
122	NT0064	Community hospitals are nonfederal, short-term general and special hospitals whose facilities and services are available to the public. The types of facilities included in this category have changed over time. Starting with 2017 data, the American Hospital Association (AHA) changed its methodology to include all general and special hospitals licensed by the appropriate state agency and accredited by one of the following: The Joint Commission, DNV GL Healthcare, Center for Improvement in Healthcare Quality, or Medicare. Data before 2017 include only hospitals registered by AHA. Because of the change in methodology, data may not be comparable across the two time periods. However, an assessment of 2015 data using both methodologies showed comparable estimates. See Sources and Definitions, Hospital, available from: https://www.cdc.gov/nchs/hus/sources-definitions/hospital.htm.
123	NT0079	In 2019, the National Health Interview Survey questionnaire was redesigned, and other changes were made to weighting and design methodology. In charts, this may be represented by a dashed vertical line. Data for 2019 and beyond have not been fully evaluated for comparability with earlier years. For more information on the 2019 National Health Interview Survey redesign and evaluation of the redesign on selected indicators, see: https://www.cdc.gov/nchs/nhis/2019_quest_redesign.htm.
124	NT0084	Deaths from diseases of heart is defined by cause-of-death codes I00-I09, I11, I13, I20-I51. Rates for 2011 and beyond are computed using 2010-based postcensal estimates. Rates for 2010 are computed based on 2010 bridged-race April 1 census counts. Rates for 2001-2009 are computed using intercensal population estimates based on the 2000 and 2010 censuses. Rates for 2000 are computed based on 2000 bridged-race April 1 census counts. Rates for 1999 are computed using intercensal population estimates based on the 1990 and 2000 censuses. See Sources and Definitions, Population Census and Population Estimates, available from: https://www.cdc.gov/nchs/hus/sources-definitions/census-population.htm. Age groups are selected to minimize the presentation of unstable age-specific death rates based on small numbers of deaths and for consistency among comparison groups.
125	NT0087	Fetal death is the intrauterine death of a fetus before delivery from the mother. In Health, United States, fetal mortality rates are calculated for deaths that occur at 20 weeks of gestation or more. See Sources and Definitions, Fetal death, available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm. Fetal death data are not available before 1995. Data by race and Hispanic origin are not available before 1999. Starting with 2014 data, the obstetric estimate of gestation at delivery replaces the gestational age measure based on the date of the last normal menses, which was used for data before 2014. For more information on the impact of this change, see Sources and Definitions, National Vital Statistics System (NVSS), Fetal Death Data Set, available from: https://www.cdc.gov/nchs/hus/sources-definitions/nvss.htm.
126	NT0088	Malignant neoplasms is defined by cause-of-death codes C00-C97. Rates for 2011 and beyond are computed using 2010-based postcensal estimates. Rates for 2010 are computed based on 2010 bridged-race April 1 census counts. Rates for 2001-2009 are computed using intercensal population estimates based on the 2000 and 2010 censuses. Rates for 2000 are computed based on 2000 bridged-race April 1 census counts. Rates for 1999 are computed using intercensal population estimates based on the 1990 and 2000 censuses. See Sources and Definitions, Population Census and Population Estimates, at: https://www.cdc.gov/nchs/hus/sources-definitions/census-population.htm. Age groups are selected to minimize the presentation of unstable age-specific death rates based on small numbers of deaths and for consistency among comparison groups.
127	NT0089	Functional limitation (or functional difficulties) is defined by the reported level of difficulty in six domains of functioning: seeing (even if wearing glasses or contact lenses), hearing (even if wearing hearing aids), mobility (walking or climbing stairs), communication (understanding or being understood by others), cognition (remembering or concentrating), and self-care (such as washing all over or dressing). Respondents with answers to one or more of the six questions are included in one of three mutually exclusive categories. Adults who respond “a lot of difficulty” or “cannot do at all” to at least one question are classified in the “a lot of difficulty or cannot do at all” category. Of the remaining respondents, adults who respond “some difficulty” to at least one question are classified in the “some difficulty” category, and adults who respond “no difficulty” to all questions are classified in the “no difficulty” category. Adults who respond “don’t know” or “refused” to all six questions are excluded. During 2010-2022, 0%-8% of respondents were missing data and excluded. See Sources and Definitions, Functional limitation, available from: https://www.cdc.gov/nchs/hus/sources-definitions/functional-limitation.htm.
128	NT0108	Obesity in youth is defined as body mass index (BMI) at or above the sex- and age-specific 95th percentile of the 2000 Centers for Disease Control and Prevention (CDC) Growth Charts. See: Ogden CL, Flegal KM. Changes in terminology for childhood overweight and obesity. National Health Statistics Reports; no 25. Hyattsville, MD: National Center for Health Statistics. 2010. Available from: https://www.cdc.gov/nchs/products/nhsr.htm. BMI equals weight in kilograms divided by height in meters squared. See Appendix II, Body mass index (BMI), available from: https://www.cdc.gov/nchs/data/hus/hus19-appendix-508.pdf. In Health, United States, the National Health and Nutrition Examination Survey (NHANES) variable named Body Mass Index is used to assign people to BMI categories. Data on both age and height are collected during a standardized physical examination conducted in mobile examination centers. Age of the participant is at the time of examination. Height is measured without shoes. Estimates exclude pregnant females. Crude percentages, not age-adjusted percentages, are shown.
129	NT0109	Starting with 2017 data, the American Hospital Association (AHA) changed its methodology to include all general and special hospitals licensed by the appropriate state agency and accredited by one of the following: The Joint Commission, DNV GL Healthcare, Center for Improvement in Healthcare Quality, or Medicare. Data before 2017 include only hospitals registered by AHA. Because of the change in methodology, data may not be comparable across the two time periods. See Sources and Definitions, Hospital, available from: https://www.cdc.gov/nchs/hus/sources-definitions/hospital.htm.
130	NT0110	The National Health and Nutrition Examination Survey (NHANES) program suspended field operations in March 2020 due to the COVID-19 pandemic. As a result, data collection for the 2019–2020 cycle was not completed. Therefore, data collected from 2019–March 2020 were combined with data from the 2017–2018 cycle to create a 2017–March 2020 prepandemic file. This file covers 3.2 years of data collection. For more information, see: https://www.cdc.gov/nchs/products/series/series02.htm.
131	NT0111	Health, United States reports single-year estimates by race, which may differ from the 2-year average estimates reported by Monitoring the Future. For 2-year average estimates by race, see Miech RA, Johnston LD, Patrick ME, O’Malley PM, Bachman JG, Schulenberg JE. Monitoring the Future national survey results on drug use, 1975-2022: Secondary school students. Ann Arbor: Institute for Social Research, The University of Michigan; 2023. Because of methodological differences between Monitoring the Future and other surveys on substance use, rates of substance use measured by these surveys are not directly comparable. See Sources and Definitions, Alcohol consumption; Binge alcohol use; Illicit drug use; Monitoring the Future (MTF); Substance use; Tobacco use, available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
132	NT9999	The quartile classification method divides data into four classes with an equal number of observations in each group, regardless of ties or outliers. Quartile classes may not be continuous; gaps between classes reflect gaps in the mapped data. The first and last quartiles may include outliers. Quartile classes may vary by year for the same indicator.
133	SC0001	National Center for Health Statistics, National Vital Statistics System, Mortality File. See Sources and Definitions, National Vital Statistics System (NVSS), available from: https://www.cdc.gov/nchs/hus/sources-definitions/nvss.htm.
134	SC0004	National Center for Health Statistics, National Health and Nutrition Examination Survey. See Sources and Definitions, National Health and Nutrition Examination Survey (NHANES), available from: https://www.cdc.gov/nchs/hus/sources-definitions/nhanes.htm.
135	SC0005	National Center for Health Statistics, National Health Interview Survey. See Sources and Definitions, National Health Interview Survey (NHIS), available from: https://www.cdc.gov/nchs/hus/sources-definitions/nhis.htm.
136	SC0012	National Center for Health Statistics, National Vital Statistics System, Linked Birth/Infant Death Data Set. See Appendix I, National Vital Statistics System (NVSS), available from: https://www.cdc.gov/nchs/data/hus/hus17_appendix.pdf.
137	SC0013	National Center for Health Statistics, National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey. See Sources and Definitions, National Ambulatory Medical Care Survey (NAMCS); National Hospital Ambulatory Medical Care Survey (NHAMCS), available from: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
138	SC0015	National Center for Health Statistics, National Vital Statistics System, Birth File. See Appendix I, National Vital Statistics System (NVSS), available from: https://www.cdc.gov/nchs/data/hus/hus17_appendix.pdf.
139	SC0016	National Center for Health Statistics, National Hospital Ambulatory Medical Care Survey. See Sources and Definitions, National Hospital Ambulatory Medical Care Survey (NHAMCS), available from: https://www.cdc.gov/nchs/hus/sources-definitions/nhamcs.htm.
140	SC0017	American Dental Association, Health Policy Institute. Supply of dentists in the U.S.: 2001–2021, Tables 1 and 3 (Copyright 2022 American Dental Association. Reprinted with permission. All rights reserved.). Any form of reproduction is strictly prohibited without prior written permission of the American Dental Association. See Sources and Definitions, American Dental Association (ADA), available from: https://www.cdc.gov/nchs/hus/sources-definitions/ada.htm.
141	SC0018	U.S. Department of Labor, Bureau of Labor Statistics. Occupational Employment and Wage Statistics. Available from: https://www.bls.gov/oes/tables.htm. See Sources and Definitions, Occupational Employment and Wage Statistics (OEWS), at: https://www.cdc.gov/nchs/hus/sources-definitions.htm.
142	SC0042	National Center for Health Statistics, National Vital Statistics System, Linked Birth/Infant Death Data Set. See Sources and Definitions, National Vital Statistics System (NVSS), available from: https://www.cdc.gov/nchs/hus/sources-definitions/nvss.htm.
143	SC0056	American Hospital Association (AHA) Annual Survey of Hospitals. Hospital Statistics, 1981, 1991–1992, 2002, 2011, 2012, 2016, 2017, 2018, 2019, 2020, 2021, 2022 editions. Chicago, IL. (Reprinted from AHA Hospital Statistics with permission, copyright 1981, 1991–1992, 2002, 2011, 2012, 2016, 2017, 2018, 2019, 2020, 2021, 2022 by Health Forum, LLC, an American Hospital Association Company.) See Sources and Definitions, American Hospital Association (AHA) Annual Survey of Hospitals, available from: https://www.cdc.gov/nchs/hus/sources-definitions/aha.htm.
144	SC0072	National Center for Health Statistics, National Vital Statistics System, Fetal Death Data Set, Birth File, and Linked Birth/Infant Death Data Set (perinatal mortality rates). See Sources and Definitions, National Vital Statistics System (NVSS), Fetal Death Data Set, available from: https://www.cdc.gov/nchs/hus/sources-definitions/nvss.htm.
145	SC0087	American Hospital Association (AHA) Annual Survey of Hospitals. Hospital Statistics, 1981, 1991–1992, 2002, 2011, 2012, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022 editions. Chicago, IL. (Reprinted from AHA Hospital Statistics with permission, copyright 1981, 1991–1992, 2002, 2011, 2012, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022 by Health Forum, LLC, an American Hospital Association Company.) See Sources and Definitions, American Hospital Association (AHA) Annual Survey of Hospitals, available from: https://www.cdc.gov/nchs/hus/sources-definitions/aha.htm.
146	SC0088	Monitoring the Future. Institute for Social Research, University of Michigan. Supported by National Institutes of Health, National Institute on Drug Abuse. See Sources and Definitions, Monitoring the Future (MTF), available from: https://www.cdc.gov/nchs/hus/sources-definitions/mtf.htm.