Pearls and pitfalls of PROMIS clinically significant outcomes in orthopaedic surgery

Introduction Patient-Reported Outcome Measurement Information System (PROMIS) was developed as a uniform and generalizable PROM system using item response theory and computer adaptive testing. We aimed to assess the utilization of PROMIS for clinically significant outcomes (CSOs) measurements and provide insights into its use in orthopaedic research. Materials and methods We reviewed PROMIS CSO reports for orthopaedic procedures via PubMed, Cochrane Library, Embase, CINAHL, and Web of Science from inception to 2022, excluding abstracts and missing measurements. Bias was assessed using the Newcastle–Ottawa Scale (NOS) and questionnaire compliance. PROMIS domains, CSO measures, and study populations were described. A meta-analysis compared distribution and anchor-based MCIDs in low-bias (NOS ≥ 7) studies. Results Overall, 54 publications from 2016 to 2022 were reviewed. PROMIS CSO studies were observational with increasing publication rates. Evidence-level was II in 10/54, bias low in 51/54, and compliance ≥ 86% in 46/54. Most (28/54) analysed lower extremity procedures. PROMIS domains examined Pain Function (PF) in 44/54, Pain Interference (PI) in 36/54, and Depression (D) in 18/54. Minimal clinically important difference (MCID) was reported in 51/54 and calculated based on distribution in 39/51 and anchor in 29/51. Patient acceptable symptom state (PASS), substantial clinical benefit (SCB), and minimal detectable change (MDC) were reported in ≤ 10/54. MCIDs were not significantly greater than MDCs. Anchor-based MCIDs were greater than distribution based MCIDs (standardized mean difference = 0.44, p < 0.001). Conclusions PROMIS CSOs are increasingly utilized, especially for lower extremity procedures assessing the PF, PI, and D domains using distribution-based MCID. Using more conservative anchor-based MCIDs and reporting MDCs may strengthen results. Researchers should consider unique pearls and pitfalls when assessing PROMIS CSOs.