(246) The Fragility Index of randomized controlled trials in obstetrics

Objective: To assess the fragility index (FI) and fragility quotient (FQ) of recently published obstetric randomized controlled trials (RCTs) in order to evaluate the robustness of study results beyond conventional statistical significance testing.

Study Design:

A retrospective analysis was conducted to identify obstetric RCTs published between 2018 and 2022 in the top medical and obstetric journals, based on impact factor. Eligible studies included those with at least one statistically significant binary primary outcome. Two independent reviewers extracted data on sample size, event and control group sizes, loss to follow-up, blinding status, type of intervention, and other relevant factors. The FIs and FQs were calculated for each study.

Results: A total of 245 RCTs were identified, and 31 met the eligibility criteria. The median and interquartile range FI for all studies was 6 (2-20), while the median FQ was 0.011 (0.004-0.034). Of the studies, 39% had an FI < 5. RCTs with placebo control groups demonstrated greater robustness compared to those with active control groups (5 [2-12]; P=0.028). Otherwise, no statistically significant relationships were observed between FI or FQ and other variables. Loss to follow-up exceeded the FI in 39% of the studies.

Conclusion: Incorporating the FI and FQ as complementary measures to traditional statistical significance testing is crucial for assessing the robustness of trial results in obstetrics. These metrics offer valuable insights into study reliability and can guide informed decisions regarding the safety and efficacy of interventions. By considering the FI and FQ, clinicians and researchers can navigate uncertainties associated with the evidence more effectively.