Validation of the Polish version of the Knee injury and Osteoarthritis Outcome Score (KOOS) in patients with osteoarthritis undergoing total knee replacement

Abstract

ObjectiveTo test the clinimetric properties and to evaluate the internal consistency, validity and reliability of the Polish version of the Knee injury and Osteoarthritis Outcome Score (KOOS) in older patients with end-stage knee osteoarthritis undergoing total knee replacement (TKR).Design and settingA prospective cohort study performed at the university hospital and the outpatient clinic.MethodsThe patients were asked to complete the KOOS questionnaire and the Short Form 36 Health Survey. We evaluated floor/ceiling effects, reliability (using Cronbach's α, intraclass correlation coefficients (ICC) and measurement error), structural validity (performing exploratory principal factor analysis), construct validity (with the use of 3 a priori hypotheses) and responsiveness (using data obtained before and after the surgery, and described by Global Perceived Effect, effect size and standardised response mean).ResultsThe study consisted of 68 participants (mean age 68.8, 82% women). The floor effects were found prior to surgery for the subscales Sports and Recreation Function, and Quality of Life. The Cronbach's α was from 0.90 to 0.92 for all subscales, indicating excellent internal consistency. The test–retest reliability at follow-up was excellent, with ICCs ranging from 0.81 to 0.86 for all KOOS subscales. The minimal detectable change ranged from 18.2 to 24.3 on an individual level and from 2.4 to 2.9 on a group level. All KOOS items were relevant, and all a priori established hypotheses were supported. Responsiveness was confirmed with a statistically significant correlation between all KOOS subscales and the Global Perceived Effect score (ranging from 0.56 to 0.70, p<0.001).ConclusionsThe Polish version of KOOS demonstrated good reliability, validity and responsiveness for use in patient groups that had undergone TKR. Since the smallest change considered clinically relevant cannot reliably be detected in individual cases, the Polish version of KOOS is advocated for assessment of groups of patients.

Validation of the Spanish Version of the Knee Injury and Osteoarthritis Outcome Score (KOOS) for Elderly Patients With Total Knee Replacement

“…TKR is a procedure with steady increase in the clinical activity and research and thus a reliable and detailed understanding of the clinical outcome is need. To our knowledge, only two previous studies have validated the KOOS specifically in a cohort of elderly patients who have undergone TKR . Overall, the results of the present study were comparable to those studies, despite the fact that one of those study had smaller sample size, and to the original KOOS …”

“…There was high test–retest reproducibility for all KOOS subscales, with ICCs ranging from 0.76 to 0.91, which revealed satisfactory stability and reproducibility of the KOOS over time in our patients. The ICCs values were comparable to those observed in previous studies performed in patients who underwent TKR . The Sports/Recreational subscale had the lowest ICC (0.76) which suggested that the questions about these activities were relevant in the patients underwent TKR.…”

“…The KOOS proved to be a valid instrument in different languages for the quantification of OA or the outcomes of specific orthopedic interventions . TKR is a procedure with steady increase in the clinical activity and research and thus a reliable and detailed understanding of the clinical outcome is need.…”

“…This later questionnaire was returned by mail in a pre‐paid envelope. The 1–2 week test–retest period was considered appropriate to assume that the clinical situation would not change during this period, and that patients would not remember their exact previous answers …”

Knee injury and osteoarthritis outcome score in patients with isolated meniscus injury; Validity and reliability

“…[5678912141516] This high Cronbach's alpha indicates that IKOOS is homogeneous and internally consistent. Only the symptom subscale in Iranian,[17] Dutch,[13] Spanish,[11] and Greek[10] version was lower than 0.7.…”