An Overview of Medical, Surgical, and Rehabilitation Outcome Measures Used in Randomized Controlled Trials of Moderate to Severe Traumatic Brain Injury

Abstract Optimal reporting of outcomes is critical for the interpretation of research findings. This review aimed to examine the utilization of outcome measures (OMs) in randomized controlled trials (RCTs) of moderate to severe TBI (MSTBI). Systematic searches were conducted up to December 2022 in MEDLINE, PubMed, Scopus, CINAHL, EMBASE and PsycINFO, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. RCTs were included if the population studied had ≥18 years and ≥ 50% had MSTBI. 662 met inclusion criteria. There was a total of 839 unique OMs across all included RCTs. Of these, only 195 (23.2%) were used in ≥4 RCTs. On average, RCTs included 1.26 OMs (range 1 to 23). A total of 495 (59%) of OMs were classified in the recovery and rehabilitation category, and 344 (41%) in the medical and surgical measures category. There was a more equal representation of OMs in high income countries (HICs) compared to low to middle income countries (LMICs), with the latter using fewer recovery and rehabilitation OMs. OMs used in RCTs of MSTBI have significant heterogeneity and variable clinical relevance, which limits the impact and generalizability of research in MSTBI, and the ability to compare across studies.