ArticleJournal of clinical epidemiology2015
Covariate adjustment had similar benefits in small and large randomized controlled trials.
Article in Journal of clinical epidemiology, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 22 papers, 2 of them syntheses that pooled it.
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Who cites it
22 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- Pooled it
- Foundational Number Sense Training Gains Are Predicted by Hippocampal-Parietal Circuits.The Journal of neuroscience : the official journal of the Society for Neuroscience · 2022Pooled it
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- Addressing digital exclusion to improve access to HIV and viral hepatitis care for people who experience criminalization: a mixed methods evaluation of a quality improvement project.International journal for equity in health · 2025Article
- Mental and Emotional Health of Youth after 24 months of Gender-Affirming Medical Care Initiated with Pubertal Suppression.medRxiv : the preprint server for health sciences · 2025Article
- Association between Heavy metals and triglyceride-glucose-related index: a mediation analysis of inflammation indicators.Lipids in health and disease · 2025Article
- The effects of etidronate on brain calcifications in Fahr's disease or syndrome: rationale and design of the randomised, placebo-controlled, double-blind CALCIFADE trial.Orphanet journal of rare diseases · 2024Article
- Covariate adjustment in randomized clinical trials with missing covariate and outcome data.Statistics in medicine · 2023Article
- Article
- The benefits of covariate adjustment for adaptive multi-arm designs.Statistical methods in medical research · 2022Article
- Two-stage matching-adjusted indirect comparison.BMC medical research methodology · 2022Article
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- Bumetanide for Irritability in Children With Sensory Processing Problems Across Neurodevelopmental Disorders: A Pilot Randomized Controlled Trial.Frontiers in psychiatry · 2022Article
- Statistical analysis of continuous outcomes from parallel-arm randomized controlled trials in nutrition-a tutorial.European journal of clinical nutrition · 2021Article
- Lessons from the CONSCIOUS-1 Study.Journal of clinical medicine · 2020Review
- Matching with time-dependent treatments: A review and look forward.Statistics in medicine · 2020Review
- An evaluation of inverse probability weighting using the propensity score for baseline covariate adjustment in smaller population randomised controlled trials with a continuous outcome.BMC medical research methodology · 2020Article
- Efficient design and analysis of randomized controlled trials in rare neurological diseases: An example in Guillain-Barré syndrome.PloS one · 2019Article
- Article
Corrections and comments
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Authors and funding
5 authors.
Funding
Abstract
objectivesCovariate adjustment is a standard statistical approach in the analysis of randomized controlled trials. We aimed to explore whether the benefit of covariate adjustment on statistical significance and power differed between small and large trials, where chance imbalance in prognostic factors necessarily differs. STUDY DESIGN AND
settingWe studied two large trial data sets [Global Use of Strategies to Open Occluded Coronary Arteries (GUSTO-I), N = 30,510 and International Stroke Trial (IST), N = 18,372] repeatedly drawing random samples (500,000 times) of sizes 300 and 5,000 per arm and simulated each primary outcome using the control arms. We empirically determined the treatment effects required to fix power at 80% for all unadjusted analyses and calculated the joint probabilities in the discordant cells when cross-classifying adjusted and unadjusted results from logistic regression models (ie, P < 0.05 vs. P ≥ 0.05).
resultsThe power gained from an adjusted analysis for small and large samples was between 5% and 6%. Similar proportions of discordance were noted irrespective of the sample size in both the GUSTO-I and the IST data sets.
conclusionThe proportions of change in statistical significance from covariate adjustment of strongly prognostic characteristics were the same for small and large trials with similar gains in statistical power. Covariate adjustment is equally recommendable in small and large trials.
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