The Fragility Index in a Cohort of Pediatric Randomized Controlled Trials

J Clin Med. 2017 Aug 14;6(8):79. doi: 10.3390/jcm6080079.


Data suggest inadequacy of common statistical techniques for reporting outcomes in clinical trials. The Fragility Index can measure how many events the statistical significance hinges on, and may facilitate better interpretation of trial results. This study aimed to assess the Fragility Index in pediatric randomized controlled trials (RCTs) with statistically significant findings published in high-quality medical journals. A Fragility Index was calculated on included trials with dichotomous positive outcomes. Analysis of the relationship between trial characteristics and the Fragility Index was performed. Of the 429 abstracts screened, 17 met the inclusion criteria and underwent analysis. The median Fragility Index was 7 with an interquartile range of 2-11. In 41% of the studies, the number of patients lost to follow-up or withdrawn prior to analysis was equal to or greater than the Fragility Index. There was no correlation between the RCT sample size and the Fragility Index (r = 0.249, p = 0.335) nor the event group size and the Fragility Index (r = 0.250, p = 0.334). There was a strong negative correlation between the original p-value and the Fragility Index (r = -0.700, p = 0.002). The Fragility Index is a calculated metric that may assist in applying clinical relevance to statistically significant outcomes in pediatric randomized controlled trials with dichotomous outcomes.

Keywords: clinical trials; pediatrics; randomized controlled trials; research methodology; statistics.