| MEASUREMENT PROPERTIES | |
| Limitations | >=5 European languages (English) |
| Observations | |
| 1. RELIABILITY | |
| A. Internal Consistency | Tested |
| Cronbach's (Describe) |
The Crohnbach α values showed a good level of internal consistency (i.e., approximating 0.8): pain (0.82), physical function (0.92),social function (0.8), general health perception (0.72) and mental function (0.77) |
| B. Reliability intraobserver or test-retest | Tested |
| Continuous scores: intraclass correlation coefficient (ICC) Dichotomus: Cohen kappa (Describe) |
All questions gave high degrees of reproducibility (test–retest repeatability) and 26 of 41 questions gave a kappa score ≥70 indicating substantial agreement between the first and second administration: pain (0.68 (0.64-0.7)), physical function (0.74 (0.69-0.8)), social function (0.79 (0.65-0.9)), general health perception (0.66 (0.64-0.74)) and mental function (0.65 (0.54-0.72)). |
| 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 | Tested |
| Brief Description |
Convergent validity (percentage of question scores correlating with the domain score better than 0.40) was good: pain (100%), physical function (94%), social function (100%), general health perception (100%) and mental function (98%) |
| C. Criterion validity | Tested |
| Comparison with a 'gold standard' Continuous scores: correlations, ROC curves Dichotomus: Sensitivity & Specificity (Describe) |
Significant correlations existed between scores of similar domains of QUALEFFO and SF-36 for pain (0.74), physical function (0.81) and mental function (0.80). The ROC curve analysis of QUALEFFO indicated that all five domains were significantly predictive of vertebral fractures than controls: pain (0.77 (0.03)), physical function (0.78 (0.03)), social function (0.67 (0.03)), general health perception (0.71 (0.03)) and mental function (0.64 (0.03)). |