VALIDATION DATA

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)

The components of the MOI‐RA are individually accepted as reliable in RA assessment. However, test–retest reliability for the aggregate measure has not been studied.

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)

The MOI‐RA is a composite measure inclusive of all 7 of the American College of Rheumatology (ACR) core set measures used to assess outcomes in RA chosen by expert consensus to represent valid dimensions of disease activity in RA, indicating  excellent face validity.

B. Construct Validity:
Structural validity
Not Tested
Hypotheses-testing Tested
Cross-cultural validity Not Tested
Brief Description
C. Criterion validity Tested
Comparison with a 'gold standard' Continuous scores:
correlations, ROC curves Dichotomus:
Sensitivity & Specificity (Describe)

The MOI‐RA was compared to ACR response criteria with mean change in the MOI‐RA from baseline to 6 months similar in patients grouped into those who did not meet ACR20, those who met ACR20 but not ACR50 response, those with ACR50 but not ACR remission, and those who met ACR remission criteria. The MOI‐RA was also compared to the DAS28 with correlations between 0.84 and 0.90 over a period of 6 months.