A methodological review of clinical outcomes reported in liver transplantation trials

Abstract Background Liver Transplantation (LT) is a life-saving treatment for end-stage liver disease, for which various outcomes are measured in randomized clinical trials (RCT). The aim of this methodological review is to evaluate and classify outcomes reported in RCT in LT. Methods PubMed and ClinicalTrials.gov were searched in July 2018 for published and ongoing RCTs on LT in the last 5 years. Studies were eligible if focusing on first LT in adult patients, with interventions during the perioperative period. Data extracted concerned LT characteristics, type of intervention, methodological characteristics and outcomes assessed. Results Of 2685 references, 55 were included with a median of 78 (40–120) patients for published trials and planned to include 117 (55–218) patients for ongoing trials. Morbidity was the most frequently used as primary outcome in 37 published (67%) and 13 ongoing trials (54%). We identified 10 different definitions for graft dysfunction, 9 for recovery outcomes and 12 different time-points for mortality. For published trials, among the 397 outcomes specified in the method section, results were reported for 283 (71%). Conclusion Outcomes reported in LT trials are very heterogeneous. A consensus approach to develop a core outcome set (COS) should be considered allowing for comparisons of results across trials. Prospero CRD42018108146.