Measurement properties of the HOOS-PS in revision total hip arthroplasty: a validation study on validity, interpretability, and responsiveness in 136 revision hip arthroplasty patients

Background and purpose - To determine whether the Hip disability and Osteoarthritis Outcome Score-Physical function Short-form (HOOS-PS) is able to appropriately evaluate physical function in revision hip arthroplasty patients, this study assesses psychometric properties of the Dutch HOOS-PS in this patient population.Patients and methods - We assessed psychometric properties of the HOOS-PS following the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) criteria. Content validity, including comprehensi-bility, comprehensiveness, and relevance of the items, was assessed using cognitive debriefing interviews in hip revision patients (n = 8) and orthopedic surgeons specialized in revi-sion surgery (n = 7). Construct validity, responsiveness, and interpretability (floor/ceiling effects) were assessed in revi-sion hip arthroplasty patients (baseline n = 136, follow-up n = 67). We formulated hypotheses a priori to assess construct validity and responsiveness using the EuroQol 5-Dimensions Health Questionnaire, Numeric Rating scale for pain, and Oxford Hip Score as comparators. All questionnaires were measured at baseline and 1 year postoperatively.Results - We found insufficient content validity of the HOOS-PS, as relevance and comprehensibility of the items scored < 85% on the COSMIN criteria for revision hip arthroplasty patients. Construct validity was sufficient as all hypotheses were confirmed (>= 75% COSMIN criteria). Interpretability was sufficient (< 15% COSMIN criteria) and responsiveness was insufficient (< 75% COSMIN criteria). Interpretation - The Dutch HOOS-PS is not able to sufficiently evaluate physical function in revision hip arthro-plasty patients. Minor changes in the items are needed for the HOOS-PS to become sufficiently content valid, because the HOOS-PS lacks relevant items and comprehensiveness.

Automated summary

This study evaluated the psychometric properties of the Dutch version of HOOS-PS in revision hip arthroplasty patients. The results showed insufficient content validity of HOOS-PS in this patient population, indicating the need for minor changes. However, construct validity and interpretability showed positive results.