Crosswalks between the Oxford hip and knee scores and the HOOS-12 and KOOS-12 instruments

S.-E. Soh, I. A. Harris, K. Cashman, S. E. Graves, I. N. Ackerman

Research output: Contribution to journalArticleResearchpeer-review

1 Citation (Scopus)


Objective: To develop and validate bi-directional crosswalks between the Oxford Hip Score (OHS) and HOOS-12 summary impact score, and between the Oxford Knee Score (OKS) and KOOS-12 summary impact score. Methods: Data were sourced from the Australian Orthopaedic Association National Joint Replacement Registry Patient-Reported Outcome Measures Program. Patients undergoing primary joint replacement for osteoarthritis who completed the OHS and HOOS-12 or OKS and KOOS-12 instruments were included in the analysis. An equipercentile method was used to create four crosswalks, with the distribution of scores smoothed using log-linear models prior to equating. Crosswalk validity was assessed through comparison of actual vs derived scores, Pearson correlation coefficients, root mean square errors (RMSE) and Bland-Altman plots. Results: Paired OHS/HOOS-12 data and paired OKS/KOOS-12 data were available for 4,513 patients undergoing total hip replacement and 5,942 patients undergoing total knee replacement, respectively. Minimal differences were observed between actual and crosswalk-derived mean scores (actual OHS 27.55 vs derived OHS 27.56; actual HOOS-12 53.28 vs derived HOOS-12 53.31; actual OKS 27.34 vs derived OKS 27.34; actual KOOS-12 50.51 vs derived KOOS-12 50.58). High correlation was observed between actual and derived scores (Pearson's r for hip-specific instruments: 0.943–0.946; Pearson's r for knee-specific instruments: 0.925–0.931). Plotted actual vs mean derived scores also indicated robust concordance across the breadth of the instrument scales. Conclusion: These crosswalks provide close approximations of actual OHS, OKS, HOOS-12 and KOOS-12 scores, as indicated by multiple validation metrics. They offer a resource for clinicians, researchers and arthroplasty registries to support PROMs score conversion and data harmonisation efforts.

Original languageEnglish
Pages (from-to)570-577
Number of pages8
JournalOsteoarthritis and Cartilage
Issue number4
Publication statusPublished - 1 Apr 2022


  • Crosswalks
  • Hip arthroplasty
  • Hip replacement
  • Knee arthroplasty
  • Knee replacement
  • Patient-reported outcome measures

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