The statistical fragility of outcomes in calcaneus fractures: A systematic review of randomized controlled trials

Abstract

IntroductionThe purpose of this study was to utilize the fragility index to assess the robustness of randomized controlled trials (RCTs) evaluating the management of calcaneus fractures. We hypothesize that the dichotomous outcomes in calcaneus fracture literature will be statistically fragile and comparable to other orthopedic specialties. MethodsWe performed a PubMed search for calcaneus fracture RCTs from 2000 to 2022 using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The fragility index (FI) of each outcome was calculated through the reversal of a single outcome event until significance was reversed. The fragility quotient (FQ) was calculated by dividing each fragility index by study sample size. The interquartile range (IQR) was also calculated for the FI and FQ. ResultsOf the 3003 studies screened, 97 met the search criteria, with 19 RCTs evaluating calcaneus fractures included in the analysis. Seventy-nine dichotomous outcomes with 30 significant (P < 0.05) outcomes and 49 with nonsignificant (P> 0.05) outcomes were identified. The overall FI and FQ of all outcomes were 6 (IQR 3–8) and 0.067 (IQR 0.032–0.100), respectively. ConclusionsThe literature surrounding calcaneus fractures may not be as statistically stable as previously thought. The sole reliance on the P value may depict misleading results. We, therefore, recommend reporting the P value in conjunction with the FI and FQ to give a robust contextualization of clinical findings in the calcaneus fracture literature.