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

ABSTRACT

OBJECTIVES: This 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. METHODS: Analyses evaluated the psychometric properties of the SDS. RESULTS: Confirmatory 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. CONCLUSIONS: These analyses support the reliability, validity, and responsiveness to change of the SDS in individuals with BED.