Measurement Properties of Patient-Reported Outcome Measures Used in Patients Undergoing Total Hip Arthroplasty: A Systematic Review.

BACKGROUND: Many patient-reported outcome measures (PROMs) have been developed to evaluate patient conditions before and after total hip arthroplasty. Also, many studies have been conducted to evaluate and compare the qualities of these instruments. Previously published reports suggest that most of these studies have poor methodology. Recently, 2 sets of criteria were developed for guiding and assessing the methodological and psychometric quality of these PROMs. We reviewed PROMs for total hip arthroplasty patients and appraised the methodological quality and psychometric evidence of evaluations of each identified instrument.

METHODS: Databases including PubMed, MEDLINE, Embase, CINAHL, the Cochrane Library, and others were searched for English-language articles published on or before April 14, 2017, using search terms related to outcome instrument, the condition or procedure of interest (hip arthroplasty), and psychometric properties. The methodological quality of the studies and the evidence of the psychometric properties were summarized and appraised using the COSMIN (COnsensus-based Standards for the selection of health Measurement INstruments) checklist and the psychometric evidence criteria. Overall psychometric ratings were derived by combining the 2 criteria.

RESULTS: Seventy-three studies investigating 26 instruments were included. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Oxford Hip Score, Harris hip score, and the Hip disability and Osteoarthritis Outcome Score (HOOS) were the most frequently assessed instruments. The WOMAC had 5 properties with positive evidence and was the highest-quality instrument overall, followed by the HOOS and the European Health Interview Survey (EUROHIS)-Quality of Life 8-item index.

CONCLUSIONS: Despite a large number of included studies, many had low COSMIN ratings. We recommend additional rigorous studies to explore the psychometric properties of these instruments. Furthermore, the development of a core outcome set for total hip arthroplasty clinical trials is needed.