Refining the Factor Structure of the All Aspects of Health Literacy Scale

Objective: Although the All Aspects of Health Literacy Scale (AAHLS) is a commonly used measure of health literacy, the psychometric evaluation approach employed in its original validation is questionable. In this study, we evaluated the psychometric properties and factor structure of the AAHLS using widely-accepted analytic methods. Methods: We collected data from 393 students from a Mid-Atlantic university. Participants completed the AAHLS in an online format. We conducted an exploratory factor analysis (EFA) to determine whether a different factor/subscale structure emerged in this sample than in the original validation sample. We ran follow-up confirmatory factor analyses (CFAs). Results: The EFA suggested an 11-item, 4-factor model. The CFA of the 4-factor model had adequate model fit but evidenced several low item loadings, suggesting that several items did not perform well. We tested a modified 8-item, 3-factor model that had good fit and high item loadings. Compared to the original factor structure, the functional health literacy subscale was removed. Conclusions: The newly proposed 3-factor/subscale model with 8 items captures communicative health literacy and 2 separate aspects of critical health literacy. Further replication in other diverse samples is warranted to investigate the psychometric properties of the AAHLS, although we recommend use of the revised version over the original.