Validity and responsiveness of the German version of the Motor Activity Log for the assessment of self-perceived arm use in hemiplegia after stroke

BACKGROUND: Rehabilitation of patients after stroke requires valid and responsive assessments for arm and hand function to determine the effectiveness of rehabilitative interventions. The Motor Activity Log (MAL) aims to assess self-perceived arm and hand use after stroke. Its clinimetric properties are incomplete and contradictory. OBJECTIVE: To investigate internal consistency, concurrent validity and responsiveness of the German MAL-30 in patients after stroke with minimal to moderate arm and hand function. METHODS: 42 patients were included in this longitudinal prospective cohort study. Internal consistency was determined in a complete-case analysis with Cronbach's α. Concurrent validity was assessed with Spearman' rho by comparing the German MAL-30 with Wolf Motor Function Test, Chedoke McMaster Stroke Assessment, isometric elbow, shoulder and grip strength at baseline, post-treatment and 6 month follow-up. Responsiveness was determined separately for lower and higher arm and hand function by calculating the standardized response mean. RESULTS: Internal consistency was excellent (Cronbach's α = 0.94-0.99), concurrent validity good to excellent (Spearman's rho = 0.64-0.99). Responsiveness was high for both functional levels from baseline to discharge (SRM = 0.93-1.43) and to follow-up (SRM = 0.95-1.34). CONCLUSION: The German MAL-30 is a valid and responsive assessment for self-perceived arm and hand use after stroke even when function is low.