VALIDATION DATA

MEASUREMENT PROPERTIES
Limitations
Observations

The MBDA measures information on biologic pathways as opposed to external signs and symptoms of disease and should provide unique information that is complementary to clinical assessment.

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)
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 development of the MBDA score started with screening 396 candidate biomarkers and ended up with 12 that were combined into a score and shown to correlate well with disease activity. The test is validated for clinical use as a disease activity marker in RA. 

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

The performance of the MBDA score compared to clinical disease activity measures was assessed in seropositive and seronegative groups. The MBDA test performed well in classifying remission/low disease activity versus moderate/high disease activity, and the correlations between the MBDA score and the DAS28‐CRP and DAS28‐ESR were relatively good. It was significantly associated with the DAS28-CRP in both seropositive (AUROC 0.77, P < 0.001) and seronegative (AUROC 0.70, P < 0.001) patients.