Touch or click     for selected variables and links to published articles using the database.

Database	Purpose	Unit of Observation	Age	Method	Timeframe	Sample size
Behavioral Risk Factor Surveillance System (BRFSS)	To monitor state-level prevalence of the major behavioral risk factors for premature morbidity and mortality.	Person	18 and above	Telephone survey	1984 - current, monthly	over 200,000 per year
National Health and Nutrition Examination Survey (NHANES)	To provide national estimates of health and nutritional status and the prevalence of detected and undetected disease.	Person	All ages	Home interview and examination	4 Cycles: 1999-current; III 88-94; II 76-80; I before 60-70	about 6000 individuals each year
National Health Interview Survey (NHIS)	To determine the amount and effects of illness/disability and associated health care utilization.	Person	All ages	Home interview	Conducted since 1960, updated about every 10-15 years;	year 2002: 36,161 households (93,386 persons, 36,831 families) sampled
Medical Expenditure Panel Survey (MEPS)	To provide estimates of individuals' health care use, expenditures, sources of payments, and insurance coverage.	Person	All ages	In-person and telephone interview	Annually since 1996	A sub-sample of the National Health Interview Survey (NHIS)
National Ambulatory Medical Care Survey (NAMCS)	To describe the characteristics of patients' visits office-based physicians who are primarily engaged in direct patient care.	Office Visits	All ages	Abstracted, using survey encounter form	Annually from 1973, except 1982-1988	Each year 3,000 physicians provide data on about 30 visits
National Hospital Discharge Survey (NHDS)	To provide nationwide information on hospital discharges using a sample of discharges from 500 hospitals in 50 states. (Note: NIS is generally the more comprehensive database. The only advantages of NHDS are data involving years prior to 1988 and data on 17 states not in NIS)	Hospital discharges	All ages	Abstracted	Annually since 1965	270,000 inpatient records yearly
Nationwide Inpatient Sample (NIS)	To provide nationwide information on hospital discharges using all discharges from 900 hospitals in 33 states (approximately 20% of all US discharges.	Hospital Discharges	All ages	Abstracted	Annually since 1988	7 million hospital stays yearly
Surveillance, Epidemiology, and End Results (SEER)	To provide data on cancer incidence, initial therapy and survival.	Incident cancer cases	All ages	Cancer registry	Annually since 1973	170,000 new cases each year