Psychometric properties of patient-reported outcome measures for health-related quality of life in multiple myeloma: a systematic review based on COSMIN guidelines

Purpose To systematically identify patient-reported outcome measures (PROMs) used to assess health-related quality of life (HRQoL), symptoms, and disease burden in patients with multiple myeloma (MM), and to appraise their measurement properties using the COSMIN methodology. Methods A systematic review was conducted in accordance with the COSMIN guideline for reviews of PROMs. Eligible studies reported PROM development, content validation, cross-cultural adaptation, or one or more measurement properties of PROMs used in adult patients with MM. Methodological quality was assessed using the COSMIN Risk of Bias checklist. The results for each measurement property were rated against the COSMIN criteria for good measurement properties, and the certainty of evidence was graded using the modified GRADE approach recommended by COSMIN. Results Twenty-six studies involving 14 PROMs were included. The EORTC QLQ-MY20 was the most frequently evaluated MM-specific module, followed by MyPOS, HM-PRO, MDASI-MM, FACT-MM, MySIm-Q, and QLICP-MM. Evidence was most often available for internal consistency, structural validity, and hypothesis testing for construct validity. By contrast, formal evidence on measurement error, criterion validity, and cross-cultural validity was seldom reported. No PROM demonstrated uniformly high-quality evidence across all key measurement properties. The EORTC QLQ-MY20 and MyPOS showed the broadest body of supportive evidence and appear to be the most defensible options for MM-specific HRQoL assessment, although additional high-quality content validity and longitudinal measurement studies remain necessary. Conclusion Current evidence supports the use of several MM-specific PROMs, particularly the EORTC QLQ-MY20 and MyPOS, but the overall evidence base remains uneven. Future research should prioritize patient-centered content validation, measurement-error evidence, cross-cultural validity, responsiveness, and interpretability to strengthen PROM selection for MM clinical trials and practice.