Reference range number line format preferred by adults for display of asthma control status

Objective: Optimal asthma self-management requires an accurate understanding of one's asthma control status. Tailored infographics are a promising way of conveying status information but little is known about which formats are effective at supporting comprehension while also being appealing to adults with asthma. Methods: In this focus group study, we compared two formats to display Asthma Control Questionnaire (ACQ) scores: a stoplight graphic and a reference range number line (RRNL). Results: Both formats supported comprehension but the RRNL was strongly preferred for its informativeness and for cueing participants to consider the self-management strategies they should undertake to improve their asthma control. Conclusions: The RRNL format may have broad appeal and can be adapted to numerous clinical variables for low health literacy patient-facing displays, as in patient portals. However, until viewers are familiar with the format, use as a communication tool in the context of a clinical visit is recommended to forestall undue alarm over abnormal/out-of-range values.