Measurement properties of rheumatoid arthritis-specific quality-of-life questionnaires: systematic review of the literature

This study conducted a systematic review of the methodological quality of the psychometric evaluation process and the quality of measurement properties of rheumatoid arthritis (RA)-specific health-related quality-of-life (HRQOL) questionnaires with the purpose of obtaining the best evidence to help in the selection of the most appropriate instrument for measuring HRQOL in RA patients. A systematic literature search was performed to identify RA-specific HRQOL questionnaires in databases. The methodological quality of the studies was assessed using the Consensus-based Standards for the Selection of Health Measurement Instruments checklist. The quality of the measurement properties was assessed using quality criteria. The evidence regarding the measurement properties was pooled using best-evidence synthesis, with considerations of the number and methodological quality of the studies, and the consistency of their findings in terms of the quality of the measurement properties. The search identified 37 studies describing 9 instruments. Best-evidence synthesis suggested that the Rheumatoid Arthritis Quality of Life (RAQoL) questionnaire had the strongest positive evidence, especially with respect to reliability, measurement error, and content validity, and moderate positive evidence with respect to hypothesis testing and responsiveness. The current evidence suggests that the best-validated instrument among the RA-specific HRQOL measures is the RAQoL questionnaire in terms of both methodological quality in the process of psychometric evaluation and the quality of the measurement properties. However, there is limited evidence regarding internal consistency and structural validity of the RAQoL. Further efforts are warranted to establish the psychometric quality of this questionnaire.