| MEASUREMENT PROPERTIES | |
| Limitations | >=5 European languages (English) |
| Observations |
There are > 50 language versions |
| 1. RELIABILITY | |
| A. Internal Consistency | Tested |
| Cronbach's (Describe) |
Knee injuries: Pain: 0.84–0.91; Symptoms: 0.25–0.75; ADL: 0.94–0.96; Sport/rec: 0.85–0.89; QOL: 0.64–0.9 Knee OA: Pain: 0.65–0.94; Symptoms: 0.56–0.83; ADL: 0.78–0.97; Sport/rec: 0.84–0.98; QOL: 0.71–0.85 |
| B. Reliability intraobserver or test-retest | Tested |
| Continuous scores: intraclass correlation coefficient (ICC) Dichotomus: Cohen kappa (Describe) |
ICC for knee injury: Pain: 0.85–0.93; Symptoms: 0.83–0.95; ADL: 0.75–0.91; Sport/rec: 0.61–0.89; QOL: 0.83–0.95 Knee OA: Pain: 0.8–0.97; Symptoms: 0.74–0.94; ADL: 0.84–0.94; Sport/rec: 0.65–0.92; QOL: 0.6–0.91 |
| C. Reliability interobserver or Measurement error | Tested |
| Standard error of measurement (SEM), smallest detectable change (SDC) or Limits of agreement (LoA) (Describe) |
The Minimal Detectable Changes in patients with knee injury were for Pain 6-6.1, for Symptoms 5-8.5, for ADL 7-8, for Sport/Rec 5.8-12, and for QOL 7-7.2. The Minimal Detectable Changes in patients with knee OA were for Pain 13.4, for Symptoms 15.5, for ADL 15.4, for Sport/Rec 19.6, and for QOL 21.1 SEM: Knee injury Pain: 2.2; Symptoms: 3.1; ADL: 2.9; Sport/rec: 2.1; QOL: 2.6 Knee OA: Pain: 7.2–10.1; Symptoms: 7.2–9; ADL: 5.2–11.7; Sport/rec: 9–24.6; QOL: 7.4–10.8 |
| 2. VALIDITY | |
| A. Content validity: face validity | Tested |
| Expert opinion (relevance and comprehensiveness) (Describe) |
Items were generated from a literature review, from the the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), version 3.0, an expert panel (patients referred to physical therapy for knee injuries, orthopedic surgeons, and physical therapists from Sweden and the US) and a pilot study of 2 questionnaires (1 for symptoms of ACL injury, 1 for symptoms of OA) in individuals with posttraumatic OA. |
| B. Construct Validity: Structural validity |
Tested |
| Hypotheses-testing | Tested |
| Cross-cultural validity | Tested |
| Brief Description |
Rasch analysis conducted using patient data 20 weeks post–ACL reconstruction showed that of the five proposed subscales in KOOS, only knee-related quality of life (QoL) and sport and recreational related function (Sport/Rec) fulfilled the criteria of a unidimensional measurement scale when applied to these patients. The three subdomains in KOOS extracted from WOMAC did not fulfill these criteria. |
| C. Criterion validity | Not Tested |
| Comparison with a 'gold standard' Continuous scores: correlations, ROC curves Dichotomus: Sensitivity & Specificity (Describe) |
Criterion validity was not evaluated due to the lack of an established gold standard measure for domains captured by KOOS |