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Age at Child Obsessive-Compulsive Disorder Onset, 2014 (ICPSR 36232)

Released/updated on: 2015-07-15
Geographic coverage: Global
Obsessive-compulsive disorder (OCD), which involves obsessional thoughts and compulsive actions performed in response to those thoughts, is an anxiety disorder that affects many children. An important question is whether early-onset OCD should be viewed as a special type of OCD, one that it has different characteristics than later-onset OCD. If so, individuals with early-onset OCD might respond differently to treatments. Consequently, the age of children at OCD onset was a focus of this study. Past researchers have reported that early age at onset is linked to more severe symptoms and that more males than females have the early-onset type of OCD. As such, we predicted that males would develop the disorder earlier than females and therefore experience more severe OCD symptoms. We used an online survey to recruit parents and caregivers of children with OCD from countries with large English-speaking populations. Girls and boys did not differ significantly in the severity of symptoms, nor was the severity of their symptoms predicted by the age at which their OCD symptoms first appeared. However, poorer family functioning was associated with greater OCD symptom severity. The role of family functioning in child OCD has been little studied, so future research should attend to the relation between family functioning and the development and severity of OCD symptoms in children.
Curated

Comparing Patient-reported Impact of COVID-19 Shelter-in-place Policies and Access to Containment and Mitigation Strategies Overall and in Vulnerable Populations, United States, 2020-2022 (ICPSR 39218)

Released/updated on: 2025-08-05
Geographic coverage: United States
Time period: 2020-04-22--2021-12-31, 2020-03-26--2023-10-26

The COVID-19 Citizen Science (CCS) Study was launched early in the pandemic to collect patient-reported information about exposures, risk behaviors and outcomes relevant to the pandemic. The Patient-Centered Outcomes Research Institute (PCORI) funded the research team to expand recruitment into CCS using PCORnet, the National Patient-Centered Clinical Research Network, and to use the resulting data to compare the patient-reported impact of pandemic associated policies. The research team systematically collected pandemic-associated policies enacted by counties across the United States (focusing in areas where there were many CCS participants), and to do so on a weekly basis from the beginning of the pandemic using publicly available sources.

Researchers combined data from various sources to answer two primary research questions (RQ):

  1. What is the comparative impact of different shelter-in-place/reopening policies, overall and in vulnerable populations, on patient-reported financial insecurity, mental health, and other subjective outcomes important to patients?
  2. What is the comparative effectiveness of county-level containment and mitigation strategies at achieving timely access to COVID-19 vaccination, testing, healthcare, information and contact tracing?

The research team collected patient-reported data from the CCS study and policy data from the U.S COVID-19 County Policy (UCCP) database. Electronic health record (EHR) data were also available from some participants recruited from health systems located across 7 U.S. states who consented and authorized use of these data for the study. Data for these participants were extracted from the PCORnet Common Data Model (CDM). Additional county-level contextual variables were included in analysis.

This collection contains CCS survey data on patient-reported anxiety with county-level policies data (DS1), respondent demographics (DS2), baseline survey results (DS3), daily (DS4) and weekly (DS5) COVID-19 symptoms reports, COVID-19 vaccination surveys repeated monthly (DS6) as well as a one-time vaccination survey (DS7), and pandemic impacts check-in surveys (DS8). CDM datasets include logistic regression model outcomes to predict study enrollment among all invited participants (DS9), codes for immunizations (DS10), laboratory tests (DS11), and procedures (DS12). County-level variables are also available for years 2021 (DS13) and 2023 (DS14).

Curated
Simple Crosstabs

Computer Assisted Quality of Life and Symptom Assessment of Complex Patients from April 2011-August 2012: Chicago, Illinois (ICPSR 34543)

Released/updated on: 2013-03-21
Geographic coverage: United States, Chicago, Illinois
Time period: 2011-04-08--2012-08-31

The purpose of this study was to expand the research capacity for comparative effectiveness evaluations of patients with multiple chronic conditions. Researchers administered a generic Quality of Life (QOL) instrument, physical symptom assessment, patient health questionnaire, and a tobacco screen through audio computer-assisted self-interviews (ACASI) and linked the responses to their electronic medical records (EMR) data. Researchers also calculated two co-morbidity indices (Chronic Disease Score and Charlson Co-morbidity Index).

Curated

Epidemiologic Catchment Area Program Sites 1-4, 1979-1983 with National Death Index Data through 2007 (ICPSR 36621)

Released/updated on: 2017-10-17
Geographic coverage: North Carolina, Baltimore, New Haven, United States, Connecticut, Missouri, St. Louis, Durham, Maryland
Time period: 1979-01-01--1982-01-01, 1980-01-01--1983-01-01, 1979-01-01--2007-01-01

The Epidemiologic Catchment Area (ECA) program of research was initiated in response to the 1977 report of the President's Commission on Mental Health. The purpose was to collect data on the prevalence and incidence of mental disorders and on the use of and need for services by the mentally ill. Independent research teams at five universities (Yale University, Johns Hopkins University, Washington University, Duke University, and University of California at Los Angeles), in collaboration with the National Institute for Mental Health, conducted the studies with a core of common questions and sample characteristics. The sites were areas that had previously been designated as Community Mental Health Center catchment areas: New Haven, Connecticut, Baltimore, Maryland, St. Louis, Missouri, Durham, North Carolina, and Los Angeles, California. Each site sampled over 3,000 community residents and 500 residents of institutions, yielding 20,861 respondents overall. The longitudinal ECA design incorporated two waves of personal interviews administered one year apart and a brief telephone interview in between (for the household sample). The diagnostic interview used in the ECA was the NIMH Diagnostic Interview Schedule (DIS), Version III (with the exception of the Yale Wave I survey, which used Version II). Diagnoses were categorized according to the DIAGNOSTIC AND STATISTICAL MANUAL OF MENTAL DISORDERS, 3rd Edition (DSM-III). Diagnoses derived from the DIS include manic episode, dysthymia, bipolar disorder, single episode major depression, recurrent major depression, atypical bipolar disorder, alcohol abuse or dependence, drug abuse or dependence, schizophrenia, schizophreniform, obsessive compulsive disorder, phobia, somatization, panic, antisocial personality, and anorexia nervosa. The DIS uses the Mini-Mental State Examination (MMSE), which measures cognitive functioning, as an indirect measure of the DSM-III Organic Mental Disorders. In the ECA survey, this diagnosis is called cognitive impairment.

This collection features data from 17,327 participants across 2,005 variables. Data from the Los Angeles, California, Catchment (UCLA) are not included. Baseline data (Wave 1) and Wave 2 data were linked to the National Death Index through 2007, which includes primary and contributing causes of death, International Classification of Disease (ICD) codes, and nature of injury variables.

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Gateways and Pathways Project (GAPP) 1997-2000, St. Louis, Missouri (ICPSR 22747)

Released/updated on: 2009-11-18
Geographic coverage: United States, Missouri, St. Louis
Time period: 1997-01-01--2000-01-01
The Gateways and Pathways Project (GAPP) extended the Youth Services Project (YSP) by examining the characteristics, training, resource connectivity, views, treatment, and referral practices of those service providers who were named by the YSP youths as having helped them. The GAPP study collected data from the youths' providers. The GAPP includes surveys of youth providers and the administrators of organizations which employ these providers. These surveys were used to measure respondent background, knowledge of the service system, the extent of referrals to and from services in the region, the degree of coordination involved in caring for youths with mental health problems, and perceived barriers to quality care. This study provides the first opportunity to test an extensive model of pathways to service use from both provider and client perspectives. This study characterizes differences in the perception of need and knowledge of services between gateway providers who link mentally ill youth to mental health services and those who do not, differences in the availability, accessibility, affordability, acceptability, and to the structural characteristics of mental health services that explain providers' actions in linking youths to mental health services, and differences in the organizational structure (support, flexibility, resources) of gateway providers that explain providers' actions in linking youths to services.
Curated

Incorporating Patient-Reported Outcomes Measurement Information System (PROMIS) Symptom Measures into Primary Care Practice [Methods Study], United States, 2014-2017 (ICPSR 39573)

Released/updated on: 2025-11-24
Geographic coverage: United States
Time period: 2014-01-01--2017-01-01

Sometimes patients don't tell their doctors about all of their symptoms. For example, they may not tell their doctors about having low energy or not sleeping well. These symptoms can be signs of a health problem. Knowing about symptoms can help doctors find ways to help patients feel better. Using patient-reported outcomes (PRO) surveys is one way for doctors to collect this information. These surveys ask how health problems and their treatments affect patients from the patients' point of view. Filling out PRO surveys helps patients tell their doctors how they are feeling.

The research team wanted to know if giving doctors information from their patients about symptoms at the start of an office visit would lead to the patients feeling better. The team collected information from patients about their symptoms using PRO surveys. The surveys tracked five common symptoms: sleep problems, pain, anxiety, depression, and low energy.

Curated
Simple Crosstabs

Midlife in the United States (MIDUS Refresher 1): Biomarker Project, 2012-2016 (ICPSR 36901)

Released/updated on: 2019-11-18
Geographic coverage: United States
Time period: 2012-10-01--2016-08-01

The MIDUS Refresher study Survey (2011-2014 ICPSR 36532) recruited a national probability sample of 3,577 adults, aged 25 to 74, designed to replenish the original MIDUS 1 baseline cohort and paralleling the five decadal age groups of the MIDUS 1 baseline survey (ICPSR 2760). The MIDUS Refresher survey employed the same comprehensive assessments as those assembled on the core longitudinal MIDUS sample, but with additional questions about impacts of the economic recession of 2008-09. The MIDUS Refresher Biomarker study (2012-2016) obtained data from 863 respondents (n=746 Main sample, n=117 African Americans from Milwaukee) who completed the MIDUS Refresher Survey.

The purpose of the Refresher Biomarker Project (Project 4) parallels that of the MIDUS 2 Biomarker project (ICPSR 29282), which collected comprehensive biological assessments on a subsample of MIDUS respondents, thus facilitating analyses that integrate behavioral and psychosocial factors with biological regulation/dysregulation, broadly defined. The aim was to use such data to explicate biopsychosocial pathways that contributed to diverse health outcomes. A further theme was to examine period effects on health (mental and physical) related to the economic recession by comparing the pre-recession MIDUS sample with the post-recession MIDUS Refresher sample. A further objective of the MIDUS Refresher sample was to strengthen cross-project analyses by increasing the sample sizes available for testing hypotheses regarding the interplay of key factors (e.g., socioeconomic status, gender, psychosocial factors, biological factors) in mid- and later-life health.

Biomarker data collection was carried out at hypothalamic-pituitary-adrenal axis, the autonomic nervous system, the immune system, cardiovascular system, musculoskeletal system, antioxidants, and three General Clinical Research Centers (at UCLA, University of Wisconsin, and Georgetown University). The biomarkers reflect functioning of the metabolic processes. Our specimens (fasting blood draw, 12-hour urine, saliva) allowed for assessment of multiple indicators within these major systems. The protocol also included assessments by clinicians or trained staff, including vital signs, morphology, functional capacities including 3 dimensional gait analysis, bone densitometry, body composition, ankle brachial index, medication usage, and a physical exam. Project staff obtained indicators of heart-rate variability, beat to beat blood pressure, respiration, and salivary cortisol assessments during an experimental protocol that included both a cognitive and orthostatic challenge. Finally, to augment the self-reported data collected in Survey (Project 1), participants completed a medical history, self-administered questionnaire, and self-reported sleep assessments. For respondents at one site (UW-Madison), objective sleep assessments were also obtained with an Actiwatch(R) activity monitor.

Curated

National Health Examination Survey, Cycle I, 1959-1962: Demographic Data and Symptoms of Psychological Distress (ICPSR 9209)

Released/updated on: 1992-02-17
Geographic coverage: United States
Time period: 1959-10-01--1962-12-01
The National Health Examination Surveys, Cycle I (NHES I), conducted during the period 1959-1962, were designed to secure statistics on the health status of the population of the United States. More specifically, their purpose was to determine the prevalence of certain chronic diseases, the status of dental health, and the distributions of auditory and visual acuity and certain anthropometric measurements. This collection contains demographic, household, and personal information for each sample person including age, race, sex, income, region, size of residence, usual activity, and sampling weight. Also included are responses to 12 items from a medical history questionnaire that were selected as indicators of psychological distress. The items include past experiences with such symptoms as faintness, sleeping problems, and sweaty hands.
Curated

Open Label, Randomized, Multicenter, Comparative Effectiveness Trial of Specific Carbohydrate and Mediterranean Diets to Induce Remission in Patients with Crohn's Disease (DINE-CD), United States, 2017-2020 (ICPSR 38590)

Released/updated on: 2023-02-02
Geographic coverage: United States
Time period: 2017-09-19--2020-03-07

The primary aim of this randomized clinical trial is to compare the effectiveness of the Specific Carbohydrate Diet (SCD) and the Mediterranean style diet (MSD) in inducing symptomatic and clinical remission in patients with Crohn's disease. Secondary objectives are to compare the effectiveness of the SCD and MSD in reducing mucosal and systemic inflammation, assessed by measuring the concentration of fecal calprotectin (FCP) and C-reactive protein (CRP) respectively; to compare the diets' effectiveness in improving fatigue, pain, and joint symptoms; and to determine the proportion of patients who continue study diets when prepared food is no longer provided without cost and their reasons for discontinuing the diets. The research aims were guided by crowdsourcing patient-generated research priorities; those that received the most support from Patient-Powered Research Network (PPRN) members were related to diet.

Based on the book Breaking the Vicious Cycle (Gottschall 1987), the Specific Carbohydrate Diet (SCD) restricts all but simple carbohydrates. Fresh fruits, vegetables, unprocessed meats, lactose-free cheeses, and certain legumes are permitted; grains, processed foods, canned foods, and milk are not permitted. The Mediterranean style diet (MSD) involves a high intake of olive oil, fruit, nuts, vegetables, and cereals; moderate intake of legumes, fish, seafood, and poultry; and low dairy intake. Red and processed meats, soda drinks, bakery foods, and sweets are not permitted. The MSD was selected as the alternative diet in this trial due to its easier implementation, consistency with U.S. Department of Agriculture and World Health Organization recommendations, and evidence of its role in overall health and specific benefits for Crohn's patients.

A total of 194 adult patients with mild to moderate Crohn's disease were enrolled and randomized into either the SCD (intervention) or MSD (control) diet groups at 33 different sites across the United States. Patients received meal delivery for their assigned diet for six weeks, then were provided instructions and recipes to adhere to the diet on their own for weeks seven through twelve. Outcome measures were taken at baseline, six weeks, and twelve weeks.

Curated

PRO-TECT: Electronic Patient Reporting of Symptoms During Outpatient Cancer Treatment, United States, 2017-2022 (ICPSR 39449)

Released/updated on: 2025-09-11
Geographic coverage: United States
Time period: 2017-10-30--2022-03-23

Patients treated for metastatic cancer, or cancer that has spread to another part of the body, often have symptoms from cancer and its treatment. They may feel tired, depressed, or nauseated. They may find it hard to do their usual activities. Better symptom tracking may help improve patients' care. For example, symptom tracking could quickly alert doctors when a patient may need a different medicine. In this study, the research team compared use of a weekly electronic symptom tracking system versus usual care for patients with cancer. Patients receiving usual care could report their symptoms to their care team during regular clinic visits. The research team wanted to see if the tracking system helped patients live longer, have better quality of life, or go to the hospital or emergency room less often. The aims of this study were as follows:

  1. Determine whether integrating electronic patient-reported outcomes (ePRO) in cancer care improves patient-centered outcomes;
  2. Elicit perspectives about benefit burden tradeoffs for integrating patient-reported outcomes into clinical workflow; and
  3. Identify barriers, facilitators, and strategies used by practices to integrate patient-reported outcomes into clinical workflow.

A total of 1,191 patients were enrolled from 52 U.S.-based community oncology practices. Randomization into intervention and control conditions occurred at the site level. Data collected as part of this study included patient clinical information; weekly symptom surveys, quality of life surveys, and cancer care surveys completed by patients; feedback on the ePRO intervention from patients, clinical research associates, nurses, and physicians; and symptom alerts sent to nursing staff. Please note that while qualitative data were collected as part of this study, they are not available.

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Raw data for meta-analysis of discriminative validity of caregiver, youth, and teacher report for pediatric bipolar disorder -- all English publications through End of 2014 (ICPSR 36245)

Released/updated on: 2015-08-17
Geographic coverage: Global
Time period: 1990-01-01--2014-01-01

Objective: To meta-analyze the diagnostic efficiency of checklists for discriminating pediatric bipolar disorder (PBD) from other conditions. Hypothesized moderators included (a) informant - we predicted caregiver report would produce larger effects than youth or teacher report; (b) scale content - scales that include manic symptoms should be more discriminating; and (c) sample design - samples that include healthy control cases or impose stringent exclusion criteria are likely to produce inflated effect sizes.

Methods: Searches in PsycINFO, PubMed, and GoogleScholar generated 4094 hits. Inclusion criteria were (1) sufficient statistics to estimate a standardized effect size, (2) age 18 years or less, and (3) at least 10 cases (4) with diagnoses of PBD based on semi-structured diagnostic interview. Multivariate mixed regression models accounted for nesting of multiple effect sizes from different informants or scales within the same sample.

Results: Data included 63 effect sizes from 8 rating scales across 27 separate samples (N=11,941 youths, 1,834 with PBD). The average effect size was g=1.05. Random effect variance components within study and between study were significant, ps<.00005. Informant, scale content, and sample design all explained significant unique variance, even after controlling for design and reporting quality.

Discussion: Checklists have clinical utility for assessing PBD. Caregiver reports discriminated PBD significantly better than teacher and youth self report, although all three showed discriminative validity. Studies using "distilled" designs with healthy control comparison groups, or stringent exclusion criteria, produced significantly larger effect size estimates that could lead to inflated false positive rates if used as described in clinical practice.

Curated
Partially restricted

Stigma and Tuberculosis in Haitian Populations: A cross-national study of the impact of stigma on patient experience and clinical outcomes in Haiti and the United States, 2003-2008 (ICPSR 30521)

Released/updated on: 2012-05-09
Geographic coverage: Haiti, United States, Florida, Tampa
Time period: 2003-01-01--2008-01-01
Tuberculosis (TB) is a public health problem of global magnitude. In the United States its victims are primarily the poor, foreign immigrants, and persons with AIDS. Efforts to control the disease are severely handicapped by the effects of social stigma and further compounded by issues of race, social class, ethnic stereotypes, immigrant status, and HIV coinfection. The study investigated the social dynamics of stigma in relation to TB in two populations particularly affected by all of these issues, Haitians in the United States and in Haiti. The theoretical framework of the study was cultural epidemiology, which combines quantitative and qualitative measures to study experience, meaning, and behavior in subpopulations of interest. The study design enabled important comparisons across national settings that highlight the differential effects of political-economic context, differences in stigma dynamics for active disease compared to latent infection, and measured the impact of stigma on adherence to preventive therapy. Study components included an ethnography of TB stigma, a cross-cultural epidemiologic study, and a community trial of adherence to preventive therapy. Study sites were South Florida, United States, and Leogane, Haiti. The study aimed to investigate: (1) differences in the degree and components of stigma across different sociocultural settings and comparison groups (community members, health care providers, patients); (2) differential stigma effects in a public vs. private, culturally competent clinic; (3) correlates of TB-related stigma; and (4) the influence of perceived stigma on adherence to latent tuberculosis therapy. Data were collected between 2003-2006 in three phases: Phase I Ethnographic Research; Phase II Cultural Epidemiologic Study; and Phase III Adherence Study. A total of 768 persons were interviewed, including 408 women (53 percent) and 360 men (47 percent). All study aims were completed with the exception of No. 2, which was not possible due to the closure of the Haitian Community Clinic in South Florida. The study consists of data from community, patient, and provider interviews. Demographic variables include sex, age, primary language, education level, employment status, marital status, and religion.
Curated

Trends in Undiagnosed Chlamydia Prevalence in Baltimore, 1997-1998 and 2006-2009 (ICPSR 35064)

Released/updated on: 2014-09-26
Geographic coverage: Baltimore, United States, Maryland
Time period: 1997-01-01--1998-09-01, 2006-09-01--2009-06-01
The 1997-1998 Baltimore STD and Behavior Survey (BSBS) and the 2006-2009 Monitoring STIs Survey Program (MSSP) collected biospecimens from adults ages 18 to 35 in Baltimore to estimate trends in undiagnosed chlamydial infection. The survey recruited a population sample of young adults to participate in an in-person survey of sexual and other sensitive behaviors and STD history. BSBS data collection was conducted over the period of January, 1997 through September, 1998. Respondents also provided a urine sample. The MSSP collected telephone survey data and eligible respondents mailed in specimens for testing. The biospecimens allowed for continuous monitoring of three STIs -- gonorrhea, chlamydial infection, and trichomoniasis. The data collection contains variables about infection symptoms, use of antibiotics, sexual activity and behavior, domestic violence, drug use and whether respondents are positive for chlamydia. Demographic information includes gender, age, education, marital status, race, and employment status.
Curated

Tsogolo la Thanzi (TLT): Verbal Autopsy Data, Malawi, 2009-2019 [Healthy Futures] (ICPSR 39181)

Released/updated on: 2024-08-19
Geographic coverage: Balaka, Malawi, Africa
Time period: 2009-01-01--2019-01-01

Tsogolo la Thanzi (TLT) was a longitudinal study in Balaka, Malawi designed to examine how young people navigate reproduction in an AIDS epidemic. Tsogolo la Thanzi means "Healthy Futures" in Chichewa, Malawi's most widely spoken language. This particular study contains the Verbal Autopsy data providing information on 36 respondents who died over the study period (2009-2019). These 36 individuals were known to be deceased through recruitment efforts to re-interview the person during a subsequent wave of data collection. However, not all groups of respondents were re-interviewed in 2012, 2015, and 2019. Therefore, the total number of deaths from the original sample is potentially more than what is reported in this particular study. The 36 verbal autopsy cases in this study represent known deaths, and should not be interpreted as an inventory of all deaths that occurred.

Curated

Undiagnosed Trichomoniasis Infection in the Population of Baltimore, MD: Data from the 2006 - 2009 Monitoring STIs Survey Program (ICPSR 35066)

Released/updated on: 2014-11-25
Geographic coverage: Baltimore, United States, Maryland
Time period: 2006-09-05--2009-08-15
The Monitoring STIs Survey Program (MSSP) monitored sexually transmitted infection (STI) prevalence among probability samples of adolescents and young adults aged 15 to 35 with landline phones in Baltimore, Maryland from 2006 to 2009. The MSSP collected survey data using telephone audio computer-assisted self-interviewing (TACASI) and biospecimens which were tested using nucleic acid amplification tests to monitor trichomonaiasis and other STIs. Respondents provided information about their sexual practices, sexual history, information about incarceration of themselves or their partners, and information about sexually transmitted diseases (STDs), STIs, and respective treatments. Demographic variables collected include gender, race, educational attainment, age, employment status, and marital status.
Curated

United States National Health Measurement Study, 2005-2006 (ICPSR 23263)

Released/updated on: 2009-06-23
Geographic coverage: United States
Time period: 2005-06-01--2006-08-01
The National Health Measurement Study (NHMS) surveyed older United States adults with a suite of health-related quality of life (HRQoL) indices to allow comparison and cross-calibration of these instruments. The design oversampled African Americans and older individuals to allow subgroup analyses. Several preference-weighted indices measuring self-reported generic HRQoL are used widely in population surveys and clinical studies in the United States and around the world. These indices are used to evaluate individual and population health. Because they have been developed using econometric methods to elicit utility weights for their scoring systems, they are generally accepted for use in cost-effectiveness analyses of health interventions. Each index uses a multidimensional representation of health, but each index covers the dimensions of health (e.g., physical function, mental function, social function, pain, other symptoms, etc.) differently, and uses questionnaires with different psychometric properties. Each index is scored so that perfect health is represented as 1.0 and dead is represented as 0.0, but they are known to have different scaling properties. Rarely have two or more of these instruments been included in a population survey, so there have been few opportunities to directly compare how they describe and measure health using multi-instrument data. In this study, respondents indicated whether they had been diagnosed with coronary heart disease, stroke, diabetes, arthritis, eye disease, sleep disorder, chronic respiratory disease, clinical depression or anxiety disorder, gastrointestinal ulcer, thyroid disorder, and/or severe chronic back pain. Census tract is not identified, however race composition, education levels, economic factors, and urbanicity of each respondent's census tract of residence are included as contextual variables. Demographic, socioeconomic, and additional health data were elicited. Respondents are characterized by census region of residence, age, gender, marital status, race, ethnicity, education, household income and assets, health insurance, weight, height, smoking status, psychological well-being scales, and everyday and lifetime discrimination items. The data were de-identified, and extensive documentation was developed. The NHMS collected data on 3,844 adults in the continental United States (1,641 males and 2,203 females, 1,086 African Americans).