| MEASUREMENT PROPERTIES | |
| Limitations | >=5 European languages (English) |
| Observations | |
| 1. RELIABILITY | |
| A. Internal Consistency | Tested |
| Cronbach's (Describe) |
Internal consistency reliability was 0.92. Excellent internal consistency (α > 0.9) was noted in patients with AS |
| B. Reliability intraobserver or test-retest | Tested |
| Continuous scores: intraclass correlation coefficient (ICC) Dichotomus: Cohen kappa (Describe) |
Actual and estimated PROMIS mental health summary scores showed low ICCs ranging from 0.727 for IRT preferred linking to 0.662. PROMIS physical health summary scores showed moderate to low ICCs, with the highest for IRT preferred linking and the lowest for the direct method (ICC(3,1): 0.801 and 0.718, respectively). Good test-retest reliability (r > 0.8)was noted in patients with AS |
| 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 | 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 |
Item-scale correlations for the 10 global health items ranged from 0.53 (global7: rating of pain) to 0.80 (global09: satisfaction with social roles). The single-factor confirmatory categorical factor analysis model for all 10 items was statistically rejectable (χ2 = 19,619.82, df = 15, P ≤ 0.001) and did not fit the data very well (CFI = 0.927; TLI = 0.961; RMSEA = 0.249). Two-factors are needed (physical and mental health) to account for the covariation among the items. |
| C. Criterion validity | Not Tested |
| Comparison with a 'gold standard' Continuous scores: correlations, ROC curves Dichotomus: Sensitivity & Specificity (Describe) |
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