This indicator uses data collected from the Behavior Risk Factor Surveillance Survey (BRFSS). The BRFSS is a state-based system of health surveys established in 1984 by CDC. Prevalence estimates are organized by different variables to estimate the number of people with asthma in different time periods and geographic areas, such as states and counties. Self-reported data have some limitations because respondents may have difficulty recalling events and understanding questions. Furthermore, cultural and language barriers and limited health knowledge can affect the quality of self-reported data.

This indicator uses data from state emergency department records and the U.S. Census Bureau. It estimates the number and rate of emergency department visits for asthma. These data can be used to identify trends and patterns of emergency department visits over time and in different geographic areas, such as states and counties.

This indicator uses data collected by hospitals. It can be used to identify trends and patterns in the occurrence of asthma hospitalizations across time and space. The data are organized by different variables to help estimate the number of asthma hospital admissions in different time periods, age groups, and geographic areas, such as states and counties. Asthma hospital admissions tend to be for more severe asthma attacks and do not include asthma among individuals who do not receive medical care, who are not hospitalized, or who are treated in outpatient settings. Differences between geographic areas may be the result of differences in the underlying population or in the diagnostic or coding techniques used by the reporting hospital.