Multiple sclerosis disease-related knowledge measurement instruments show mixed performance: a systematic review.

OBJECTIVES:This review aimed to summarize the evidence on the measurement properties of available disease-related knowledge measurement instruments in people with multiple sclerosis. STUDY DESIGN AND SETTING:We performed a literature search in the MEDLINE (PubMed), CINAHL (EBSCOhost), and PsycINFO (EBSCOhost) databases from inception to February 10, 2021. Eligible studies were reports developing a disease-related knowledge measurement instrument or assessing one or more of its measurement properties. We assessed the methodological quality of the included studies independently using the "COSMIN Risk of Bias" checklist. We graded the quality of the evidence using a GRADE approach. RESULTS:Twenty-four studies provided information on 14 measurement instruments. All instruments showed sufficient evidence for content validity, three for structural validity, and seven for hypothesis testing for construct validity. Cross-cultural validity and criterion validity were not assessed in any instrument. Only two instruments showed sufficient evidence for the internal consistency of their scores, and two others for their test-retest reliability. Responsiveness was assessed in one instrument, but it was rated as indeterminate. CONCLUSION:Based on the available evidence, two instruments can be recommended for use, two are unrecommended, and five have the potential to be recommended for use but require further research.