Multimethod development and investigation of psychometric properties of a new scale of physicians’ self-efficacy in caring for adults with intellectual disability

Low physician confidence in caring for adults with intellectual disability (ID) can compromise care quality and health outcomes and may exacerbate healthcare barriers for this population. Although training interventions targeting self-efficacy can improve providers' practice, an instrument with evidence of validity specifically designed to assess physicians' self-efficacy in caring for adults with ID is not yet available. This paper describes the development of the SEC-ID and examines its psychometric properties as a brief measure of physicians' self-efficacy. In Step 1, the SEC-ID was drafted based on a literature review and revised by experts, who judged it to be clear and comprehensive, resulting in a 15-item scale with five-point Likert responses. In Step 2, the SEC-ID was administered to 279 U.S. physicians and its psychometric properties were examined using methods from Classical Test Theory and Rasch Measurement Theory. Results provided evidence of construct validity, supporting a largely unidimensional, reliable score with the greatest measurement precision at lower levels of self-efficacy. Items were discriminant, non-redundant, and unambiguous; their ordering along the latent continuum was stable and reproducible, and the response categories functioned as intended. Measurement invariance was supported across gender, physician status (attending vs. resident), prior ID-related training, and contact with individuals with ID outside the workplace. Higher SEC-ID scores were positively associated with prior ID-related training and with physicians' willingness and comfort in interacting with individuals with ID. Overall, these properties distinguish the SEC-ID from existing measures and support its use as a brief tool for research and training evaluation.