TY - JOUR
T1 - The Fragility Index in Multicenter Randomized Controlled Critical Care Trials
AU - Ridgeon, Elliott E.
AU - Young, Paul J.
AU - Bellomo, Rinaldo
AU - Mucchetti, Marta
AU - Lembo, Rosalba
AU - Landoni, Giovanni
PY - 2016/3/9
Y1 - 2016/3/9
N2 - OBJECTIVES:: Recent literature has drawn attention to the potential inadequacy of frequentist analysis and threshold p values as tools for reporting outcomes in clinical trials. The fragility index, which is a measure of how many events the statistical significance of a result depends on, has been suggested as a means to aid the interpretation of trial results. This study aimed to calculate the fragility index of clinical trials in critical care medicine reporting a statistically significant effect on mortality (increasing or decreasing mortality). DATA SOURCES:: Literature search (PubMed/MEDLINE) to identify all multicenter randomized controlled trials in critical care medicine. STUDY SELECTION:: We identified 862 trials; of which 56 fulfilled eligibility criteria and were included in our analysis. DATA EXTRACTION:: Calculation of fragility index for trials reporting a statistically significant effect on mortality, and analysis of the relationship between trial characteristics and fragility index. DATA SYNTHESIS:: The median fragility index was 2 (interquartile range, 1–3.5), and greater than 40% of trials had a fragility index of less than or equal to 1. 12.5% of trials reported loss to follow-up greater than their fragility index. Trial sample size was positively correlated, and reported p value was negatively correlated, with fragility index. CONCLUSIONS:: In critical care trials reporting statistically significant effects on mortality, the findings often depend on a small number of events. Critical care clinicians should be wary of basing decisions on trials with a low fragility index. We advocate the reporting of fragility index for future trials in critical care to aid interpretation and decision making by clinicians.
AB - OBJECTIVES:: Recent literature has drawn attention to the potential inadequacy of frequentist analysis and threshold p values as tools for reporting outcomes in clinical trials. The fragility index, which is a measure of how many events the statistical significance of a result depends on, has been suggested as a means to aid the interpretation of trial results. This study aimed to calculate the fragility index of clinical trials in critical care medicine reporting a statistically significant effect on mortality (increasing or decreasing mortality). DATA SOURCES:: Literature search (PubMed/MEDLINE) to identify all multicenter randomized controlled trials in critical care medicine. STUDY SELECTION:: We identified 862 trials; of which 56 fulfilled eligibility criteria and were included in our analysis. DATA EXTRACTION:: Calculation of fragility index for trials reporting a statistically significant effect on mortality, and analysis of the relationship between trial characteristics and fragility index. DATA SYNTHESIS:: The median fragility index was 2 (interquartile range, 1–3.5), and greater than 40% of trials had a fragility index of less than or equal to 1. 12.5% of trials reported loss to follow-up greater than their fragility index. Trial sample size was positively correlated, and reported p value was negatively correlated, with fragility index. CONCLUSIONS:: In critical care trials reporting statistically significant effects on mortality, the findings often depend on a small number of events. Critical care clinicians should be wary of basing decisions on trials with a low fragility index. We advocate the reporting of fragility index for future trials in critical care to aid interpretation and decision making by clinicians.
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U2 - 10.1097/CCM.0000000000001670
DO - 10.1097/CCM.0000000000001670
M3 - Article
AN - SCOPUS:84960455175
JO - Critical Care Medicine
JF - Critical Care Medicine
SN - 0090-3493
ER -