Evidence of Content Validity of the Duchenne Video Assessment Scorecards from a Delphi Panel Study


Real World Data - Disease registries, natural history, post marketing surveillance

Poster Number: 172


Marielle Contesse, PhD, Linda Lowes, PT, PhD, Michelle White, PhD, Laura Dalle Pazze, Christine McSherry, RN, Mindy Leffler, Med


1. Casimir, 2. Nationwide Children's Hospital, 3. Optum, 4. Charley's Fund, 5. Casimir, 6. Casimir

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.