Psychometric properties of two questionnaires in the context of total wrist arthroplasty.

INTRODUCTION: Patient-rated outcome measures are frequently used to assess the results of total wrist arthroplasty, but their psychometric properties have not yet been evaluated in this group of patients. The purpose of our study was to assess the psychometric properties of the Danish Quick Disabilites of Arm Shoulder and Hand (QuickDASH) and Patient-rated Wrist Evaluation questionnaires in patients with total wrist arthroplasty. METHODS: In a prospective cohort of 102 cases, we evaluated the QuickDASH. Furthermore, in a cross-sectional study and a test-retest on a subgroup of the patients, we evaluated the Patient-rated Wrist Evaluation. RESULTS: Internal consistency and reproducibility were very high (Cronbach's alpha 0.96/0.97; Spearman's rho 0.90/ 0.91; intraclass coefficient 0.91/0.92), and there were no floor or ceiling effects. The responsiveness of the QuickDASH was high (standardised response mean 1.06 and effect size 1.07). The construct validity of both scales was confirmed by three a priori formulated hypotheses: a moderate, negative correlation of scores with grip-strength; a moderate, positive correlation with pain and a very weak or no correlation with mobility. Rheumatoid patients scored significantly higher on the QuickDASH than other patients did. The scores of both questionnaires were very closely related. CONCLUSION: Both questionnaires are valid and equivalent for use in patients with total wrist arthroplasty. FUNDING: This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. TRIAL REGISTRATION: not relevant.