| MEASUREMENT PROPERTIES | |
| Limitations | <5 European languages (English) |
| Observations |
The JAFAR cannot be administered to children younger than 7 years of age, making it unsuitable for use in younger children with early disease onset. |
| 1. RELIABILITY | |
| A. Internal Consistency | Tested |
| Cronbach's (Describe) |
Cronbach's alpha of JAFAR-P was 0.96 Cronbach's alpha of JAFAR-C was 0.83 |
| B. Reliability intraobserver or test-retest | Not Tested |
| Continuous scores: intraclass correlation coefficient (ICC) Dichotomus: Cohen kappa (Describe) |
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| C. Reliability interobserver or Measurement error | Tested |
| Standard error of measurement (SEM), smallest detectable change (SDC) or Limits of agreement (LoA) (Describe) |
No significant difference between scores reported by parents on the JAFAR-P and children (JAFAR-C). |
| 2. VALIDITY | |
| A. Content validity: face validity | Not Tested |
| Expert opinion (relevance and comprehensiveness) (Describe) |
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| B. Construct Validity: Structural validity |
Tested |
| Hypotheses-testing | Tested |
| Cross-cultural validity | Not Tested |
| Brief Description |
JAFAR-C and JAFAR-P correlated most strongly with each other (r = 0.75) and with the JAFAS (r = 0.69); all P < 0.05. Known groups validity. Control group of healthy children scored significantly lower than group with JRA, demonstrating the test's ability to discriminate between children with and without JRA. |
| C. Criterion validity | Not Tested |
| Comparison with a 'gold standard' Continuous scores: correlations, ROC curves Dichotomus: Sensitivity & Specificity (Describe) |
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