Assessment of Validity, Reliability and Responsiveness of Korean Knee Injury and Osteoarthritis Outcome Score(KOOS) for the Knee Injury

Seo, Seung Suk; Chung, Kyung Chil; Kim, Young Bok

Abstract

PURPOSE: To assess the suitability of the Korean KOOS (Knee injury and osteoarthritis outcome score) as a patient-centered clinical measurement of the validity, reliability and responsiveness to the treatment of knee injuries.
MATERIALS AND METHODS
One hundred and eight patients who had experienced an arthroscopic ACL reconstruction or a menisectomy between Jan. 2002 and Jun. 2003 were examined immediately after surgery, and 6 and 12 months after surgery. The SF-36 and Lysholm knee scale were administered simultaneously to each case in order to calculate the inter-item correlation.
RESULTS
Measurements of the test-retest reliability showed that all intra-class coefficients (ICC) were measured as r=0.75-0.89 and Cronbach's alpha was 0.73-0.81. Regarding the validity, there was a strong correlation with the SF-36 and the Lysholm, subscales (SF-36 vs KOOS: Physical functioning vs ADL (r=0.67)/Physical functioning vs Sports and recreational activities (r=0.61)/Bodily pain vs Pain (r=0.63)). In terms of the responsiveness, the average score measured preoperatively, and three, six and nine months showed a gradual increase. The effect size of pain, symptoms and ADL at postoperative 6 months was 0.8-1.1. A larger effect size was observed in the QOL (1.5) and sports and recreational function (1.3) at 3 months after surgery (n=25).
CONCLUSION
The validity, reliability and responsiveness of the Korean KOOS was confirmed and is considered to be a useful clinical metrology for a knee injury.