Development and Validation of the Consumer Health Activation Index

Background. Although there has been increasing interest in patient engagement, few measures are publicly available and suitable for patients with limited health literacy. Objective. We sought to develop a Consumer Health Activation Index (CHAI) for use among diverse patients. Methods. Expert opinion, a systematic literature review, focus groups, and cognitive interviews with patients were used to create and revise a potential set of items. Psychometric testing guided by item response theory was then conducted among 301 English-speaking, community-dwelling adults. This included differential item functioning analyses to evaluate item performance across participant health literacy levels. To determine construct validity, CHAI scores were compared to scales measuring similar personality constructs. Associations between the CHAI and physical and mental health established predictive validity. A second study among 9,478 adults was used to confirm CHAI associations with health outcomes. Results. Exploratory facto...