ArticlePloS one2020
The weakness of fragility index exposed in an analysis of the traumatic brain injury management guidelines: A meta-epidemiological and simulation study.
Article in PloS one, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 15 papers, 3 of them syntheses that pooled it.
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Who cites it
15 citing papers in PubMed, 3 syntheses or guidelines pooled it, 29 citations in OpenAlex.
- Exploring the fragility of meta-analyses in ophthalmology: a systematic review.Eye (London, England) · 2024Pooled it
- The Statistical Fragility of Operative vs Nonoperative Management for Achilles Tendon Rupture: A Systematic Review of Comparative Studies.Foot & ankle international · 2022Pooled it
- Meta-analyses in paediatric surgery are often fragile: implications and consequences.Pediatric surgery international · 2021Pooled it
- Randomized controlled trial outcomes for nonoperative management of lateral epicondylitis of the elbow are statistically fragile: a systematic review.JSES reviews, reports, and techniques · 2025Article
- Robustness of Randomized Control Trials Supporting Current Neurosurgery Guidelines.Neurosurgery · 2023Article
- Fragility of statistically significant outcomes in randomized trials comparing bariatric surgeries.International journal of obesity (2005) · 2023Review
- Assessing the robustness of results from clinical trials and meta-analyses with the fragility index.American journal of obstetrics and gynecology · 2023Review
- Empirical assessment of fragility index based on a large database of clinical studies in the Cochrane Library.Journal of evaluation in clinical practice · 2023Article
- Paediatric surgical trials, their fragility index, and why to avoid using it to evaluate results.Pediatric surgery international · 2022Article
- The Fragility Index for Assessing the Robustness of the Statistically Significant Results of Experimental Clinical Studies.Journal of general internal medicine · 2022Article
- Fragility indices for only sufficiently likely modifications.Proceedings of the National Academy of Sciences of the United States of America · 2021Article
- Fragility Index and Fragility Quotient in Randomized Controlled Trials on Corticosteroids in ARDS Due to COVID-19 and Non-COVID-19 Etiology.Journal of clinical medicine · 2021Review
- How Robust are the Evidences that Formulate Surviving Sepsis Guidelines? An Analysis of Fragility and Reverse Fragility of Randomized Controlled Trials that were Referred in these Guidelines.Indian journal of critical care medicine : peer-reviewed, official publication of Indian Society of Critical Care Medicine · 2021Article
- The statistical fragility of vertebroplasty outcomes: A systematic review of randomized controlled trials.Journal of craniovertebral junction & spineReview
- Beyond the Fragility Index.Pharmaceutical statisticsArticle
Corrections and comments
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Authors and funding
4 authors at 3 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
objectivesTo perform fragility index (FI) analysis on the evidence that forms the basis of the guidelines for the management of severe traumatic brain injury (TBI), and develop a deeper understanding of the pitfalls associated with FI.
designMeta-epidemiological analysis and numerical simulations.
methodsThe Brain Trauma Foundation guidelines (4th edition) for management of severe TBI were used to identify relevant randomised controlled trials (RCTs). FI based on Fisher's exact test and relative risk was performed on eligible RCTs. The relationship between FI, event counts and P values was explored by exhaustively considering different combinations of outcomes for studies of total size ranging from 80 to 10000. Sample size calculations were also performed for a range of power, baseline risk and relative risk, to determine the influence of study design on FI.
resultsFI analysis of the severe TBI management guidelines revealed that most studies were associated with a low FI. In the majority of studies, FI was of a similar magnitude to the number lost to follow-up. The simulations revealed that while FI was inversely related to P value, a wide range of FI may be associated with a given P value. FI is also affected by sample size, baseline risk and effect size. Sample size calculations suggest that aside from very high-powered studies, most are likely to yield low FI values in the range typically encountered in the literature.
conclusionsMany studies are underpowered and are expected to be associated with a small FI. Furthermore, FI over-simplifies the complex, non-linear relationships between sample size, effect size and P value, which hinder comparisons of FI between studies. FI places undue importance on the "significance" of P values and accordingly should only be used sparingly.
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