RESUMO
Federally sponsored health surveys are a critical source of information on public health in the United States. The National Center for Health Statistics (NCHS) is the nation's principal health statistics agency and is responsible for collecting accurate, relevant, and timely data. NCHS conducts several population-based national surveys as well as collecting vital statistics data, which are used by a broad range of users (researchers and policy makers, among others) to evaluate and profile the health of the American people. These national health surveys provide rich cross-sectional information on risk factors such as smoking, height and weight, health status, and socioeconomic circumstances, but information on longitudinal outcomes is often missing. Demand is increasing to incorporate information from additional sources in order to enhance the availability and quality of information on exposures and outcomes.