ABSTRACT
The 41-item Quality of Life Questionnaire of the European Foundation for Osteoporosis (QUALEFFO-41) is a widely used and freely available patient-reported outcome measure (PROM). However, data on its reliability, validity, and responsiveness remain unclear. Therefore, this study aimed to systematically review the measurement properties of the QUALEFFO-41. A systematic search of MEDLINE, EBSCOhost, and Cochrane Library from their inception up to December 2022 was performed. Data were extracted, and the methodological quality of each measurement property was evaluated according to the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) guidelines. The evidence of the measurement properties was rated against the updated criteria for good measurement properties, and the quality of evidence was graded using the modified GRADE approach. A total of 99 articles were identified, of which eight studies were included in the review. The QUALEFFO-41 is categorized as B as it demonstrated moderate quality evidence for sufficient content validity, moderate-to-high quality evidence for sufficient hypothesis testing for construct validity (except for the social function domain for convergent validity), and very low-quality evidence for sufficient responsiveness. For structural validity and internal consistency, only the domains of pain and general health perception were sufficient with low-quality evidence. For reliability, only the domain of physical function was sufficient with low-quality evidence. None of the studies reported measurement error, cross-cultural validity, and criterion validity. The QUALEFFO-41 may be a promising, valid, and reliable PROM to assess HRQoL in osteoporosis patients with vertebral fractures. However, future studies must focus on good methodological quality to strengthen the evidence of measurement properties, especially on structural validity, reliability, responsiveness, and cross-cultural validity. The systematic review evaluated the measurement properties of the QUALEFFO-41 questionnaire for assessing Health-Related Quality of Life (HRQoL) in osteoporosis patients. The review found moderate-to-high-quality evidence for construct validity but limited evidence for responsiveness and other properties. Future studies should focus on strengthening the evidence, particularly for structural validity, reliability, responsiveness, and cross-cultural validity. The QUALEFFO-41 shows promise as a valid and reliable PROM for HRQoL assessment in osteoporosis patients.