Focused Evidence Review: Psychometric Properties of Patient-Reported Outcome Measures for Chronic Musculoskeletal Pain

Developing successful interventions for chronic musculoskeletal pain requires valid, responsive, and reliable outcome measures. The Minneapolis VA Evidence-based Synthesis Program completed a focused evidence review on key psychometric properties of 17 self-report measures of pain severity and pain-related functional impairment suitable for clinical research on chronic musculoskeletal pain. Pain experts of the VA Pain Measurement Outcomes Workgroup identified 17 pain measures to undergo systematic review. In addition to a MEDLINE search on these 17 measures (1/2000-1/2017), we hand-searched (without publication date limits) the reference lists of all included studies, prior systematic reviews, and-when available-Web sites dedicated to each measure (PROSPERO registration CRD42017056610). Our primary outcome was the measure's minimal important difference (MID). Secondary outcomes included responsiveness, validity, and test-retest reliability. Outcomes were synthesized through evidence mapping and qualitative comparison. Of 1635 abstracts identified, 331 articles underwent full-text review, and 43 met inclusion criteria. Five measures (Oswestry Disability Index (ODI), Roland-Morris Disability Questionnaire (RMDQ), SF-36 Bodily Pain Scale (SF-36 BPS), Numeric Rating Scale (NRS), and Visual Analog Scale (VAS)) had data reported on MID, responsiveness, validity, and test-retest reliability. Seven measures had data reported on three of the four psychometric outcomes. Eight measures had reported MIDs, though estimation methods differed substantially and often were not clinically anchored. In this focused evidence review, the most evidence on key psychometric properties in chronic musculoskeletal pain populations was found for the ODI, RMDQ, SF-36 BPS, NRS, and VAS. Key limitations in the field include substantial variation in methods of estimating psychometric properties, defining chronic musculoskeletal pain, and reporting patient demographics. Registered in the PROSPERO database: CRD42017056610.