Psychometric Properties of the Brief Pain Inventory-Short Form and Revised Short McGill Pain Questionnaire Version-2 in Musculoskeletal Conditions
Abstract
Introduction: Comprehensive pain assessment depends on the use of psychometrically valid patient-reported outcome measures (PROMs). The Brief Pain Inventory-Short Form (BPI-SF) and Revised Short McGill Pain Questionnaire Version-2 (SF-MPQ-2) are general-use multidimensional pain assessment tools commonly used in musculoskeletal conditions. Understanding all relevant measurement properties supports stronger decisions about PROMs.
Thesis Objectives: The overarching objective of this thesis was to determine the sufficiency of measurement evidence backing the use of the BPI-SF and SF-MPQ-2 in musculoskeletal conditions. Specifically, a systematic review was conducted to locate, summarize and compare the quality and content of psychometric evidence backing the BPI-SF and SF-MPQ-2 in musculoskeletal conditions. Based on this review, the gap in evidence regarding the reliability and agreement properties (reproducibility) of SF-MPQ-2 was examined among patients with musculoskeletal shoulder pain.
Methods: For the systematic review, we searched four databases to identify relevant citations. Two reviewers independently screened, extracted and appraised (using MacDermid and COSMIN guidelines) all psychometric reports on both tools in musculoskeletal conditions. To determine the SF-MPQ-2 reproducibility, a convenience sample of adults diagnosed with musculoskeletal shoulder pain (baseline, n=195; test-retest, n=48) completed the SF-MPQ-2 twice. Cronbach alpha (α), intraclass correlations coefficient (ICC2,1), agreement parameters (SEM, MDC) and Bland-Altman plots were assessed.
Results: High quality evidence indicated both tools have high internal consistency (α = 0.83-0.96); and that they are moderately related (r = 0.3-0.69) to other health-related outcome measures. More studies of better quality have evaluated the BPI-SF responsiveness (n=5), retest reliability (n=3), known group validity (n=2) and structural validity (n=3), compared to the SF-MPQ-2. Our analysis of the SF-MPQ-2 reproducibility established internal consistency as satisfactory (α, 0.83-0.95), relative reliability as good (neuropathic, intermittent, and affective subscales: 1CC2,1= 0.78 - 0.88) to excellent (total and continuous subscale scores: 1CC2,1= 0.92 - 0.95). Agreement was within acceptable limits and there was no evidence of systematic bias.
Conclusion: A greater volume of evidence of better quality currently supports the BPI-SF although emerging evidence suggest the SF-MPQ-2 has excellent reliability and agreement properties when used to assess adults with musculoskeletal shoulder pain. Direct comparisons of the two scales in different contexts are needed.
Keywords: Brief Pain Inventory; Musculoskeletal Conditions; McGill Pain Questionnaire; Reliability; Psychometric Properties; Reproducibility; Systematic Review