Behavior risk factor surveillance system or BRFSS is a United States national self-report telephone survey that provides prevalence data concerning behavioral risk factors associated with the nation's most common health conditions. A collaborative effort between the CDC and each state health department, it is the world's largest and nation's leading ongoing telephone survey. Established in 1984, today, all 50 states and 3 U.S. territories participate in this survey. Each year's survey questionnaire is designed by each state's survey coordinator from its state health department and designated CDC staff. Every year over 400 thousand noninstitutionalized U.S. resident adult telephone survey interviews are conducted to collect data about chronic health conditions and risk behaviors associated with the nation's leading causes of morbidity and mortality, including blood pressure, seat belt usage, smoking, drug use, cholesterol, cancer (breast, cervical, colorectal, prostate), immunization, sleep practices, health care access, alcohol use, drinking and driving, sex practices, HIV, and oral health.
Many of the BRFSS questions come from other national surveys that collect information via face-to-face interviews, telephone interviews, and physical examination. These surveys include the National Center for Health Statistics (NHANES), National Health and Nutrition Interview Survey (NHIS), National Survey of Family Growth (NSFG), Current Population Survey (CPS), and National Survey on Drug Use and Health (NSUH). Therefore, BRFSS prevalence estimates can be compared with other national surveys to assess their validity and accuracy. A comprehensive review of numerous published scholarly studies confirms its validity and reliability.
There are three parts to the survey questionnaire- core, optional, and state-added questions. The core contains three sections. Core questions are a standardized set of questions used by all states. The annual core consists of questions that are asked yearly. Rotating core questions are two sets of questions used in alternating years. The emerging core consists of 5 questions that address current or emerging issues and are usually apart of the core for one year. Optional modules include rotating core questions that are not in use that year. State-added questions are questions each state chooses to add based on its individual needs.
Throughout the year, survey interviews are conducted by each state's health department using the same core questionnaire, standardized sampling methods, and methodology. This data is then submitted to the CDC monthly for further processing and analysis. Weighting and adding calculated variables are statistical and analytical methods that decrease potential bias and ensure that the data collected is representative of the population from which it is derived. Survey data is published online by the CDC on an annual basis. Each year's questionnaire, background, design data, survey results from 1984 to the present, as well as analytical and statistical tools for further disseminating and processing are available on the CDC's BRFSS website.