Evaluating functional disability in clinical trials of lisdexamfetamine dimesylate in binge eating disorder using the Sheehan Disability Scale

Abstract

ObjectivesThis study examined Sheehan Disability Scale (SDS) performance in binge eating disorder (BED) and explored relationships between SDS and BED outcomes using data from three placebo‐controlled lisdexamfetamine (LDX) studies (two short‐term, dose‐optimized studies and one double‐blind, randomized‐withdrawal study) in adults with Diagnostic and Statistical Manual of Mental Disorders, fourth edition, text revision (DSM‐IV‐TR)–defined BED.MethodsAnalyses evaluated the psychometric properties of the SDS.ResultsConfirmatory factor analysis supported a unidimensional total score in the short‐term studies, with internal consistency (Cronbach's α) being 0.878. Total score exhibited good construct validity, with moderate and statistically significant correlations observed with Yale–Brown Obsessive Compulsive Scale modified for binge eating, Binge Eating Scale (BES), and EuroQol Group 5‐Dimension 5‐Level health status index scores. Known‐groups validity analysis for the short‐term studies demonstrated a significantly lower total score at end of study in participants considered “not ill” versus “ill” based on Clinical Global Impressions–Severity scores. SDS total score changes in the short‐term studies were greater in responders than nonresponders based on binge eating abstinence or BES score. In the randomized‐withdrawal study, SDS scores increased relative to baseline to a greater extent in participants randomized to placebo than LDX.ConclusionsThese analyses support the reliability, validity, and responsiveness to change of the SDS in individuals with BED.