| MEASUREMENT PROPERTIES | |
| Limitations | >=5 European languages (English) |
| Observations | |
| 1. RELIABILITY | |
| A. Internal Consistency | Tested |
| Cronbach's (Describe) |
This scale has acceptable internal consistency (Cronbach’s alpha 0.82–0.91) |
| B. Reliability intraobserver or test-retest | Tested |
| Continuous scores: intraclass correlation coefficient (ICC) Dichotomus: Cohen kappa (Describe) |
Test–retest reliability coefficients for PSE was 0.87, for FSE was 0.85, and for OSE was 0.90 |
| C. Reliability interobserver or Measurement error | Not Tested |
| Standard error of measurement (SEM), smallest detectable change (SDC) or Limits of agreement (LoA) (Describe) |
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| 2. VALIDITY | |
| A. Content validity: face validity | Tested |
| Expert opinion (relevance and comprehensiveness) (Describe) |
A rheumatologist generated 23 original items; these items were refined, and an additional 20 items added following 3 focus groups of people with arthritis. |
| B. Construct Validity: Structural validity |
Tested |
| Hypotheses-testing | Tested |
| Cross-cultural validity | Tested |
| Brief Description |
Initial validation sample (n =97) produced a 2-factor solution (other symptoms, function) using 25 items. The replication study (n = 144) produced a 3-factor solution (pain, other symptoms, function) using 20 items. Developers stated that the choice between the 2 and 3 factor solution was arbitrary, and they based the decision on the importance of pain and the performance of the other symptoms subscale in regard to depression. |
| C. Criterion validity | Not Tested |
| Comparison with a 'gold standard' Continuous scores: correlations, ROC curves Dichotomus: Sensitivity & Specificity (Describe) |
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