Cross-cultural adaptation and psychometric properties of the Dutch version of the Hand Function Sort in patients with complaints of hand and/or wrist.

Background: Musculoskeletal complaints of arm, neck, and shoulder (CANS) can lead to loss of work productivity. To assess the functional consequences of impairments in work, patient-reported outcomes can be important. The Hand Function Sort (HFS) is a 62-item pictorial questionnaire that focuses on work task performance. The aims of this study were the cross-cultural adaptation of HFS into HFS-Dutch Language Version (HFS-DLV) (Part I) and determining construct validity, internal consistency, test-retest reliability, responsiveness and floor/ceiling effects of HFS-DLV (Part II).

Methods: I: Translation into Dutch using international guidelines. II: Construct validity was assessed with Spearman's correlation coefficients between the HFS-DLV and the Dutch version of the QuickDASH, PRWHE, PDI, RAND-36, NRS-pain, and work ability score. Internal consistency was assessed using Cronbach's α and reliability by a test-retest procedure. A global rating scale of change was used after 4-8 weeks of hand therapy to determine responsiveness.

Results: I: Forty patients were included, and no items were changed. II: 126 patients with hand, wrist, and/or forearm disorders classified as specific or nonspecific CANS. Six predefined hypotheses (50%) were confirmed. Cronbach's α: 0.98. Test-retest reliability: ICC of 0.922. AUC of 0.752. There were no floor/ceiling effects.

Conclusions: I: Translation process into the HFS-DLV went according to plan. II: For construct validity, the presumed direction of correlations was correct, but less than 75% of hypotheses were confirmed. Internal consistency was high, suggesting redundancy. Reliability and responsiveness of the HFS-DLV were good. HFS-DLV can be used in research or clinical practice for Dutch patients with CANS, to evaluate self-reported functional work ability.