Journal of General Internal Medicine

, Volume 34, Issue 7, pp 1236–1243 | Cite as

The Fragility Index in a Cohort of HIV/AIDS Randomized Controlled Trials

  • Cole WayantEmail author
  • Chase Meyer
  • Rebecca Gupton
  • Mousumi Som
  • Damon Baker
  • Matt Vassar
Original Research


HIV/AIDS is associated with significant morbidity, mortality, and financial burden. For these reasons, robust clinical evidence is critical. We aim to investigate the fragility index, fragility quotient, and risk of bias of clinical trial endpoints in HIV medicine. The fragility index represents the minimum amount of trial endpoint “nonevents” changed to “events” in one trial arm required to nullify statistical significance. The fragility quotient contextualized the fragility index by dividing the index by the total trial sample size. We selected eligible trials from the Department of Health and Human Services guideline for the use of antiretroviral agents in HIV-1-infected adults and adolescents. We calculated the fragility index and fragility quotient for all included trials. The Cochrane “risk of bias” Tool 2.0 was used to evaluate the likelihood and sources of bias in the included trials. Thirty-nine RCTs were included for our analysis of fragility. Thirty-six were included for our analysis of the risk of bias. The median fragility index was 5. Three RCTs were at high risk of bias, all due to the selection of the endpoint or statistical test. Twenty had some concerns for risk of bias. The analyzed HIV medicine RCT endpoints were fragile, overall. This indicates that a median of 5 patients across all included studies would nullify the statistical significance of the endpoints. Furthermore, we found evidence that concerns for bias are present at a high rate.


HIV acquired immunodeficiency syndrome randomized controlled trials fragility index fragility quotient 


Compliance with Ethical Standards

Conflict of Interest

The authors declare that they do not have a conflict of interest.

Supplementary material

11606_2019_4928_MOESM1_ESM.docx (20 kb)
Supplementary Table 1 (DOCX 20 kb)


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Copyright information

© Society of General Internal Medicine 2019

Authors and Affiliations

  • Cole Wayant
    • 1
    Email author
  • Chase Meyer
    • 1
    • 2
  • Rebecca Gupton
    • 3
  • Mousumi Som
    • 3
  • Damon Baker
    • 3
  • Matt Vassar
    • 1
    • 2
  1. 1.Department of Biomedical SciencesOklahoma State University Center for Health SciencesTulsaUSA
  2. 2.Department of Psychiatry and Behavioral SciencesOklahoma State University Center for Health SciencesTulsaUSA
  3. 3.Internal MedicineOklahoma State University Medical CenterTulsaUSA

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