Translation and validation of the Swedish version of the problematic experience of therapy scale (PETS-Swe) for patients with peripheral nerve injuries in the hand.

Abstract

Introduction: The Problematic Experience of Therapy Scale (PETS) identifies barriers to home-based exercise programs but has not been validated in hand therapy populations. This study aimed to translate the extended PETS into Swedish and evaluate its content and construct validity in patients undergoing early sensory relearning following peripheral nerve injury.

Methods: The PETS was translated into Swedish (PETS-Swe) following established cross-cultural adaptation guidelines. Fifty-three patients with peripheral nerve injuries completed the PETS-Swe four weeks into a home-based sensory relearning program. Exercise adherence was monitored using a daily exercise diary. Content validity was assessed through expert review (face validity) and patient ratings of item relevance, clarity, and ambiguity. Item-level (I-CVI) and scale-level (SCVI) content validity indices were calculated, alongside modified kappa statistics for interrater agreement. Construct validity was examined using Spearman's correlation between PETS-Swe scores and reported exercise frequency.

Results: Translation revealed no major discrepancies. Most items demonstrated high content validity (I-CVI and S-CVI >0.8), though lower relevance scores were observed in the technical subscale (I-CVI: 0.65-0.69). Interrater agreement was good to excellent across all items (K >0.74 for items 1-17; K = 0.6-0.74 for items 18-20). Expert reviewers confirmed strong face validity. Moderate negative correlations were found between PETS-Swe scores and exercise adherence (rho = -0.40 to exercise log; -0.57 to diary), supporting construct validity.

Discussion: The Swedish version of the extended PETS is a valid tool for identifying barriers to home-based sensory relearning in patients with peripheral nerve injuries undergoing hand therapy.