Year: 2010
Type: letter
Abstract: In their recently published article, Dr Aberegg and colleagues described interesting results of a literature search for randomized controlled trials comparing mortality of therapies for critically ill adults in fi ve high impact journals over a 10 year period [1]. Th e authors show that the predicted delta (the eff ect size of a therapy compared to control) used for power calculations was substantially larger than the observed delta in the majority of the included studies. Th ey conclude that this fi nding, referred to as ‘delta infl ation’, led to underpowered trials in the fi eld of critical care medicine. We agree that treatment eff ects are small in this fi eld of medicine and that many critical care trials have been underpowered. Th is problem is particularly relevant to the fi eld of neurocritical care after traumatic brain injury [2]. Th e IMPACT (International Mission on Prognosis and Clinical Trial Design in Traumatic Brain Injury) Study Group extensively investigated possible causes and solutions and recently reported recommendations for improving the design and analysis of future clinical trials in traumatic brain injury to increase statistical power [3]. Th ese include the use of relatively broad enrolment criteria instead of strict patient selection [4], covariate adjustment for baseline patient characteristics [5], and ordinal rather than dichotomous outcome analysis [6]. In our opinion these recommendations are also applicable to other fi elds of critical care research characterized by heterogeneous patient populations. We submit that adopting these recommendations in future trials will increase the chance of detecting small but clinically relevant treatment eff ects in critical care medicine. Competing interests All authors are members of the IMPACT Study Group. The work of the IMPACT Study Group is funded by a grant of the US National Institutes of Health (NS-042691). Author details 1
Source: Critical Care
DOI: 10.1186/cc9021
Authors: Bob Roozenbeek, Hester F Lingsma, Ewout W Steyerberg, Andrew IR Maas, the IMPACT Study Group
Institutions: Erasmus MC, Antwerp University Hospital
Language: English
Subfield: Statistics and Probability
Field: Mathematics
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $4,190
OpenAlex ID: W2152582806