| MEASUREMENT PROPERTIES | |
| Limitations | >=5 European languages (English) |
| Observations | |
| 1. RELIABILITY | |
| A. Internal Consistency | Tested |
| Cronbach's (Describe) |
0.61-0.82 |
| B. Reliability intraobserver or test-retest | Tested |
| Continuous scores: intraclass correlation coefficient (ICC) Dichotomus: Cohen kappa (Describe) |
Good-to-excellent test–retest reliability with kappa scores for each item ranging from 0.65–0.81 (all P <0.001) |
| 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 | Tested |
| Expert opinion (relevance and comprehensiveness) (Describe) |
MDHAQ was derived from the HAQ and includes an index of the three RA core data set measures (physical function, pain, and global estimate) |
| B. Construct Validity: Structural validity |
Tested |
| Hypotheses-testing | Tested |
| Cross-cultural validity | Not Tested |
| Brief Description |
The 2 items regarding participation in sports and walking 2 miles do not fit Rasch model criteria for unidimensionality. In addition, missing MDHAQ items affect the final score more than for HAQ-II, but less than for HAQ or MHAQ. |
| C. Criterion validity | Tested |
| Comparison with a 'gold standard' Continuous scores: correlations, ROC curves Dichotomus: Sensitivity & Specificity (Describe) |
The MDHAQ and HAQ have been shown to be highly correlated; however, average MDHAQ scores have been shown to be 0.34 lower than HAQ scores. |