Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Nov 1;237(5):731-736.
doi: 10.1097/XCS.0000000000000800. Epub 2023 Jul 7.

Statistical Power of Randomized Controlled Trials in Trauma Surgery

Affiliations

Statistical Power of Randomized Controlled Trials in Trauma Surgery

Arthur Berg et al. J Am Coll Surg. .

Abstract

Background: Our purpose was to conduct a bibliometric study investigating the prevalence of underpowered randomized controlled trials (RCTs) in trauma surgery.

Study design: A medical librarian conducted a search of RCTs in trauma published from 2000 to 2021. Data extracted included study type, sample size calculation, and power analyses. Post hoc calculations were performed using a power of 80% and an alpha level of 0.05. A CONSORT checklist was then tabulated from each study as well as a fragility index for studies with statistical significance.

Results: In total 187 RCTs from multiple continents and 60 journals were examined. A total of 133 (71%) were found to have "positive" findings consistent with their hypothesis. When evaluating their methods, 51.3% of articles did not report how they calculated their intended sample size. Of those that did, 25 (27%) did not meet their target enrollment. When examining post hoc power, 46%, 57%, and 65% were adequately powered to detect small, medium, and large effect sizes, respectively. Only 11% of RCTs had complete adherence with CONSORT reporting guidelines and the average CONSORT score was 19 out of 25. For positive superiority trials with binary outcomes, the fragility index median (interquartile range) was 2 (2 to 8).

Conclusions: A concerningly large proportion of recently published RCTs in trauma surgery do not report a priori sample size calculations, do not meet enrollment targets, and are not adequately powered to detect even large effect sizes. There exists opportunity for improvement of trauma surgery study design, conduct, and reporting.

PubMed Disclaimer

Comment in

References

    1. Olubimpe A, Dickson L, Teegan I, et al. A systematic review of power and sample size reporting in randomized controlled trials within plastic surgery. Plast Recon Surg. 2012;130:78e–86e.
    1. Faber J, Fonseca L. How sample size influences research outcomes. Dent Press J Orthodon. 2014;19:27–29.
    1. Bedard P, Krzyzanowska M, Pintilie M, et al. Statistical power of negative randomized controlled trials presented at American Society for Clinical Oncology. J Clin Onc. 2007;25:3482–3487.
    1. Keen H, Pile K, Hill C. The prevalence of underpowered randomized clinical trials in rheumatology. J Rheum. 2005;32:2083–2088.
    1. Harvey L, Glinsky J, Bowden J, et al. How well do randomised controlled trials of physical interventions for people with spinal cord injury adhere to the CONSORT guidelines? An analysis of trials published over a 10-year period. Spinal Cord. 2014;52:795–802.

LinkOut - more resources