Tracking Asthma

Tracking asthma involves collecting data about people diagnosed and living with asthma and collecting data about people who experience asthma attacks. This includes tracking the number of people ever told by a physician that they have asthma, the number of asthma-related physician visits, the number of hospital or emergency room visits, and the number of deaths due to asthma. Public health officials rely on many sources of data including:

• surveys of self-reported symptoms or diagnoses,
• medical encounters of people receiving care for asthma, and
• death certificates.

Each source gives a snapshot of different aspects of the burden of asthma. While we can use survey data to estimate the number of people suffering from asthma attacks, we do not have data on exactly when, where, and how often individuals have asthma attacks.

The Tracking Network includes data on asthma hospital stays, emergency department visits for asthma, and asthma prevalence which is the number of people diagnosed with and living with asthma. These data are useful in providing estimates about the geographic distribution and effects of asthma among different populations. These estimates can be used to plan and evaluate asthma interventions.

The hospital admissions data available on the Tracking Network present state hospital discharge data. The Tracking Network is using hospital admission dates while other public health programs use the hospital discharge dates to count asthma cases. This may cause a difference in asthma rates between the Tracking Network and other public health Web sites.

The emergency department visits for asthma data available on the Tracking Network can be used to identify trends and patterns of emergency department visits over time and in different geographic areas. These data are obtained from state emergency department records and the U.S. Census Bureau.

The asthma prevalence data used on the Tracking Network are obtained from CDC's Behavioral Risk Factor Surveillance Survey (BRFSS). The BRFSS is a state-based system of health surveys established in 1984.