Background: People with Duchenne muscular dystrophy (DMD) adopt compensatory movement patterns to maintain independence as muscles get weaker. The Duchenne Video Assessment (DVA) tool provides a standardized way to document and assess ease of movement. Caregivers video record patients doing specific movement tasks at home using a secure mobile application. Physical therapists (PTs) score the videos using scorecards with prespecified compensatory movement criteria.
Objective: To gather expert input on the compensatory criteria indicative of clinically meaningful change in disease to include in scorecards for 15 movement tasks.
Approach: We conducted 2 rounds of a Delphi panel, a method for building consensus among experts. We recruited 8 PTs who have evaluated ≥50 DMD patients in clinic and participated in ≥10 DMD clinical trials. In Round 1, PTs completed a preliminary questionnaire to evaluate compensatory criteria clarity and rate videos of 4 DMD patients performing each movement task using scorecards. In Round 2, PTs participated in an in-person discussion to reach consensus (≥75% agreement) on all compensatory criteria with disagreement or scoring discrepancies during Round 1.
Results: Of the 8 PTs, 38% practiced physical therapy for ≥20 years, 75% provided physical therapy to ≥200 DMD patients, and 38% participated in ≥15 DMD clinical trials. Of 153 version 1 compensatory criteria, 70 (46%) were revised in Round 1. Of 150 version 2 compensatory criteria, 85 (57%) were revised in Round 2. The 8 PTs reached 100% agreement on all changes made to scorecards during the in-person discussion except the Run scorecard due to time restrictions. A subset of the panel (3 PTs) met after the in-person discussion and reached consensus on the compensatory criteria to include in the Run scorecard.
Conclusion: Expert DMD PTs confirmed that the compensatory criteria included in the DVA scorecards were appropriate and indicative of clinically meaningful change in the disease.