Measuring health sciences students' attitudes toward persons with disabilities: Is one scale better than another?

Negative attitudes toward persons with disabilities (PWDs) can lead to stigmatization and exclusion, underscoring the need for effective tools to measure and address such attitudes in educational settings. This study compares the psychometric properties of two scales used to assess attitudes toward PWDs among health science learners: the Multidimensional Attitudes Scale Toward Persons with Disabilities (MAS) and the Attitudes and Perspectives Toward Persons with Disabilities Scale (APPD). This research examines the internal consistency, factor stability, factor replicability, and convergent validity of these scales across different measurement occasions using data from second-year Medical (n = 102) and Doctor of Physical Therapy (n = 39) students. An exploratory factor analysis (EFA) with bootstrapping revealed that both scales yielded three-factor solutions with varying degrees of factor stability and replicability. The MAS's three-factor structure-Affect, Cognitive, and Behavioral-demonstrated stronger internal consistency (Cronbach's alpha >= 0.838) and better factor replicability (Tucker congruence coefficients >= 0.88) than the APPD across pre- and post-intervention datasets. Confirmatory factor analysis was conducted as a second test of replicability and revealed that neither scale demonstrated ideal model fit when applying post-intervention data to the pre-intervention measurement model. Convergent validity analysis indicated a medium positive correlation between MAS and APPD scores (r = 0.368, p < 0.001), suggesting only moderate overlap in the constructs they measure. When used with health sciences students, the MAS demonstrated superior psychometric properties compared to the APPD. However, both scales showed limitations and inconsistencies across measurement occasions, highlighting the need for further refinement and validation.