Epidemiology

BRFSS (Behavioral Risk Factor Surveillance System) is the nation's premier system of health-related telephone surveys conducted by the CDC and state health departments. Established in 1984, it collects state-level data on US adult residents regarding health-related risk behaviors, chronic health conditions, and use of preventive services. Conducts over 400,000 interviews annually across all 50 states, DC, and US territories. Topics include: high blood pressure, cholesterol, diabetes, asthma, BMI/obesity, smoking/tobacco use, alcohol consumption, physical activity, diet, cancer screening (breast, cervical, colorectal), immunizations, HIV/AIDS, mental health, and healthcare access. Data includes demographic variables (age, sex, race/ethnicity, income, education) and survey weights for population-representative estimates. Completely free, publicly available on the CDC website — no registration or data use agreement required. Available in SAS, ASCII, and CSV formats. Often used alongside NHANES for complementary population health analyses (BRFSS = larger sample, broader coverage; NHANES = deeper phenotyping with physical exams and lab measurements).

BRFSS, CDC, behavioral risk, telephone survey, public health, chronic disease, risk factors, US surveillance

NHANES is a program of studies by the US CDC designed to assess the health and nutritional status of adults and children in the United States. It combines interviews, physical examinations, and laboratory tests across 2-year continuous cycles (1999-present). The survey includes: demographics (age, sex, race/ethnicity, income); ~40+ questionnaire components (diabetes DIQ, cardiovascular CDQ, depression PHQ-9/DPQ, sleep SLQ, smoking SMQ, alcohol ALQ, kidney KIQ, physical function PFQ, osteoporosis OSQ, weight history WHQ); physical examinations (anthropometry BMX, blood pressure BPX, DXA bone density, spirometry SPX, hearing AUXAR, vision VIX, accelerometry PAXRAW); and ~50+ laboratory biomarkers (comprehensive metabolic panel BIOPRO, complete blood count CBC, HbA1c GHB, glucose GLU, insulin INS, lipids TCHOL/HDL, CRP/HSCRP, vitamin D VID, ferritin FERTIN, testosterone TST, hepatitis/HIV/HPV serology, PFAS chemicals, heavy metals, cotinine). Dietary intake data includes 2-day 24-hour recall (DR1IFF/DR2IFF). NHANES is multi-ethnic and US-representative with survey weights. Total: ~1,600 SAS XPT files, ~5 GB. Available at no cost, no registration required. Widely used for epidemiological research, biomarker GWAS replication, and cross-population comparisons with biobank data (UKBB, BBJ).

NHANES, CDC, health survey, biomarkers, nutrition, demographics, epidemiology, US representative, public health