The data are also used to present the characteristics of those dying in the United States, to determine life expectancy, and to compare mortality trends with other countries. Preliminary and final annual data are available. Basic demographic information, such as age, race, gender, and income, is also collected to enable analysis of crime by various subpopulations. This survey teaches us about the health and diet of people in the United States. Over the years, this survey has lead to improvements in the food we eat and the health care we receive.
Information is collected on all household members.
Questions are designed to retain comparability to previous NHIS surveys for reporting of activity limitation due to physical, mental, or emotional problems. Information on activity limitation is collected on each family member. Findings are based on a national sample of visits to the emergency departments and outpatient departments of noninstitutional general and short-stay hospitals, exclusive of Federal, military, and Veterans Administration hospitals, located in the 50 States and the District of Columbia. The survey uses a four-stage probability design with samples of geographically defined areas, hospitals within these areas, clinics within hospitals, and patient visits within clinics. Annual data collection began in 1992.