MG-ADL: Still a relevant outcome measure

Introduction: The aim of this analysis was to examine the performance of the Myasthenia Gravis-specific Activities of Daily Living scale (MG-ADL) during a multicenter scale validation study. Methods: Consecutive MG patients were assessed with several MG outcome measures, including the MG-ADL. Statistical tests included descriptive analysis, Pearson correlation, and sensitivity/specificity. Results: Eighty-seven patients completed the MG-ADL, MG Composite (MGC), and MG 15-item Quality of Life scale (MG-QOL15) on the first visit, and 76 returned for the second visit. At the first visit, there was a strong positive correlation between MG-ADL and MGC (r 1/4 0.85, P < 0.0001) and MG-QOL15 (r 1/4 0.76, P < 0.0001). Correlation of the delta MG-ADL score and physician impression of change between the visits was strong (r 1/4 0.70, P < 0.0001). A 2-point improvement in the MG-ADL best predicted clinical improvement. Test-retest analysis demonstrated a high reliability coefficient. Conclusions: The MG-ADL correlates strongly with newer, validated MG outcome measures. A 2-point improvement in the MG-ADL indicates clinical improvement. The MG-ADL is useful as a research tool and in routine clinical management.