To our knowledge, no functional outcome measure has been developed and validated for Dupuytren's disease. We aimed to develop and validate a patient-reported functional outcome measure for Dupuytren's disease.
Patients with Dupuytren's disease (n = 9) and medical experts (n = 7) provided input and opinions about limiting activities that were difficult to perform because of Dupuytren's disease for item generation. The provisional scale was studied in an independent sample of patients (n = 85) for item reduction according to response distribution, reliability, redundancy, and loading in a 1-factor solution. The final scale was evaluated as follows: reliability using Cronbach's alpha coefficient and test-retest intraclass correlation coefficient from the previous 85-patient population, and construct validity and responsiveness after needle aponeurotomy in another independent 53-patient sample. For construct validity, convergent validity and divergent validity were tested. The clinically important change was estimated relative to a 1-point categorical change on the Tubiana scale.
A 52-item provisional scale was generated and reduced to the final 9-item scale called the Unité Rhumatologique des Affections de la Main (URAM) scale (total score 0-45). The scale showed good to excellent reliability and suitable construct validity. The URAM score improved after needle aponeurotomy: the standardized effect size was 0.56. The estimated clinically important change of the URAM scale was 2.9 points.
We provide the first patient-reported functional measure for Dupuytren's disease. The URAM scale demonstrated suitable psychometric properties, and is short and convenient enough for easy use in daily practice and in clinical studies.