| MEASUREMENT PROPERTIES | |
| Limitations | |
| Observations | |
| 1. RELIABILITY | |
| A. Internal Consistency | Not Tested |
| Cronbach's (Describe) | |
| B. Reliability intraobserver or test-retest | Not Tested |
| Continuous scores: intraclass correlation coefficient (ICC) Dichotomus: Cohen kappa (Describe) |
Future studies need to evaluate reliability. |
| C. Reliability interobserver or Measurement error | Not Tested |
| Standard error of measurement (SEM), smallest detectable change (SDC) or Limits of agreement (LoA) (Describe) |
|
| 2. VALIDITY | |
| A. Content validity: face validity | Not Tested |
| Expert opinion (relevance and comprehensiveness) (Describe) |
The SCTC-DI has been validated against its own derivation data set from the Australian Scleroderma Cohort Study (ASCS) cohort as well as an external data set from the CSRG cohort. internal and external validity were demonstrated against the endpoints of mortality and morbidity |
| B. Construct Validity: Structural validity |
Tested |
| Hypotheses-testing | Not Tested |
| Cross-cultural validity | Not Tested |
| Brief Description |
In ASCS (Australian Scleroderma Cohort Study) and CSRG (Canadian Scleroderma Research Group) cohorts, patients with early disease (within 2 years of disease onset) had steadily increasing numbers of damage items. |
| C. Criterion validity | Tested |
| Comparison with a 'gold standard' Continuous scores: correlations, ROC curves Dichotomus: Sensitivity & Specificity (Describe) |
Receiver operating characteristic curves showed a good discriminatory capability for the SCTC-DI , and KaplanMeier survival estimates showed a statistically significant relationship between the damage score and time to death or worsening of morbidity. |