The Responsiveness of Oxford Knee Score in Iranian Patients with Knee Osteoarthritis Following Physiotherapy Intervention

Document Type : Original Articles


1 Associate Professor, Department of Physiotherapy, School of Rehabilitation Sciences AND Musculoskeletal Research Center, Isfahan University of Medical Sciences, Isfahan, Iran

2 Associate Professor, Department of Physical Therapy, School of Paramedical Sciences AND Orthopedic Research Center Mashhad University of Medical Sciences, Mashhad, Iran

3 Assistant Professor, Department of Physical Therapy, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran

4 MSc Student, Student Research Committee (Treata), Department of Physiotherapy, School of Rehabilitation Sciences, Isfahan University of Medical Sciences, Isfahan, Iran



Introduction: The main purpose of physiotherapy in patients with knee osteoarthritis includes reducing pain, improving individual functional abilities, and increasing quality of life. Thus, the therapists need a tool to measure the outcome of these changes after intervention. In order to utilize these tools, they should have acceptable validity, reliability, and responsiveness. The Oxford Knee Score (OKS) is one of the most common tools used for assessment of the patients with knee osteoarthritis. However, to our knowledge, there has been no study on its responsiveness in this group of the patients. Therefore, the purpose of this study was to investigate the responsiveness of this outcome measure, and to measure minimal clinically important change in the patients with knee osteoarthritis following physiotherapy.Materials and Methods: 146 Iranian men and women with knee osteoarthritis referred to physiotherapist were entered the study via a nonrandomized convenience sampling method. The Oxford Knee Score was completed in the first session, and again after four weeks of physiotherapy. In the last session, the patients filled a 7-item retrograde Likert questionnaire, tooResults: The area under the curve (AUC) of 0.78, and δ correlation coefficient of 0.59 indicated high responsiveness of Oxford Knee Score. The sensitivity and specificity of scale was 0.50 and 0.91, respectively. The minimal clinically important change (MCIC) of this tool was 6.5.Conclusion: Our findings provide evidence for selection of appropriate outcome measure for assessment of changes in these patients. The minimal clinically important change of this tool was determined which provide practical information for clinicians to make decision on clinical significance of changes in patients status.


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  • Receive Date: 22 January 2018
  • Revise Date: 25 March 2023
  • Accept Date: 22 May 2022
  • First Publish Date: 22 May 2022