Evaluation of the Michigan Asthma Call Back Survey, 2005-2010

BACKGROUND: The Michigan Department of Community Health (MDCH), in collaboration the Office for Survey Research (OSR) at Michigan State University, began conducting the Asthma Call Back Survey (ACBS) in 2005 with funding from the National Asthma Control Program at the Centers for Disease Control and Prevention (CDC). This telephone survey is a follow-up to the Michigan Behavioral Risk Factor Survey for adults who identify themselves or a child in their household as having a physician-diagnosis of asthma. Survey questions cover symptoms, triggers, and management techniques. Results from all states conducting the ACBS are weighted to produce comparable prevalence estimates.

METHODS: We applied the 2001 MMWR article, “Updated Guidelines for Evaluating Public Health Surveillance Systems” to ACBS data from 2005-2010, focusing on the surveillance system’s simplicity, flexibility, data quality, acceptability, representativeness, timeliness and stability. Accessibility and utility of the data were also assessed. Key stakeholders included CDC staff involved in the creation of the ACBS, MDCH epidemiologists responsible for data analyses and dissemination, OSR contractors charged with data collection, and both current and non-current data users from asthma-related organizations. These stakeholders completed in-person or telephone interviews (n=17). Refusal and completion rates for the 2010 Michigan ACBS were compared to the median rates for all states conducting the survey.

RESULTS: Stakeholder interviews rated the Michigan ACBS high on data quality, flexibility; fair on timeliness, representativeness, acceptability, simplicity; and poor on stability. MDCH posts asthma prevalence tables, factsheets, and burden reports on the asthma website; however non-current users were unaware of these resources. Among current users, ACBS data support grant applications and program initiatives and are summarized for journal publications, educational materials and presentations. In 2010, the Michigan ACBS had a refusal rate of 32.5% among eligible adults who refused or terminated early and an interview completion rate of 94.9% among eligible adults who started the interview. Similarly, in 2010 for the child survey the refusal rate was 27.2% and the interview completion rate was 96.7%. The Michigan ACBS completion and refusal rates were better than the median rates for all states conducting the survey.

CONCLUSIONS: The Michigan ACBS is the only source of detailed, state-level data on asthma triggers, symptoms and management. Standardized survey protocols yield high-quality asthma data, yet better dissemination of this data is necessary to increase utility of the survey. The most critical obstacle to the ACBS is funding. The continuation of the Michigan ACBS is crucial for monitoring asthma trends and guiding interventions in the state.