1984 to present; not all states participated prior to 2001
Mode of Collection
Sample survey: telephone interview (cell and land line).
The Behavioral Risk Factor Surveillance System (BRFSS) is a state-based system of telephone health surveys that collects information on health risk behaviors, preventive health practices, and health care access primarily related to chronic disease and injury. The survey was established in 1984. Data are collected monthly in all 50 states, the District of Columbia, Puerto Rico, the U.S. Virgin Islands, and Guam.
Issues addressed in the BRFSS include tobacco use and other behavioral risk factors, preventive care practices, health care coverage, HIV/AIDS knowledge and prevention, physical activity, and fruit and vegetable consumption.
U.S. civilian noninstitutionalized population ages 18 years and older residing in households.
Data collection is conducted separately by each state. The design uses state-level, random digit dialed probability samples of the adult (ages 18 and older) population. All projects use a disproportionate stratified sample design except for Guam, Puerto Rico, and the U.S. Virgin Islands who use a simple random sample design. The questionnaire consists of 3 parts: (1) a core component of questions used by all states, which includes questions on demographics, and current health-related conditions and behaviors; (2) optional CDC modules on specific topics (e.g., cardiovascular disease, arthritis), that states may elect to use; and (3) state-added questions, developed by states for their own use. The state-added questions are not edited or evaluated by CDC. Interviews are generally conducted using computer-assisted telephone interviewing (CATI) systems. Data are weighted for noncoverage and nonresponse.
Response Rates and Sample Size
More than 350,000 adults are interviewed each year. Response rates vary by state: in 2017, the land line response rate ranged between 22% and 64% while the cell phone response rate ranged from 31% to 69%. The combined response rate ranged from 31% to 64%.
The BRFSS is conducted independently by each state and therefore methodologies may vary. Pooled national estimates may not take into account these differences and so may differ from estimates obtained using data sources that use methodologies designed to produce national estimates. Also, the BRFSS was not designed to produce county-specific estimates in most states although county-specific estimates may be presented if there are more than 50 respondents in a county.