SynthesisBMC medical research methodology2019
Ideal vs. real: a systematic review on handling covariates in randomized controlled trials.
Synthesis in BMC medical research methodology, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 16 papers, 2 of them syntheses that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
16 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- Pooled it
- A systematic review of randomisation method use in RCTs and association of trial design characteristics with method selection.BMC medical research methodology · 2022Pooled it
- Planning a method for covariate adjustment in individually randomised trials: a practical guide.Trials · 2022Trial
- Adjustment for Baseline Covariates to Increase Efficiency in RCTs with Binary Endpoint: A Comparison of Bayesian and Frequentist Approaches.International journal of environmental research and public health · 2021Trial
- Covariate Adjustment for Wilcoxon Two Sample Statistic and Test.Statistics in medicine · 2026Article
- Minimization of expected balance distribution differences: optimization of the randomized allocation algorithm based on the Pocock-Simon design.BMC medical research methodology · 2026Article
- High Cardiorespiratory Fitness and Vigorous Physical Activity Relate to Select Pain Sensitivity Assessments in Healthy Adults: A Cross-Sectional Study.Pain research & management · 2026Article
- Smoking Cessation Among Patients with Chronic Pain in a Comparative Effectiveness Trial.Journal of general internal medicine · 2025Article
- Workflows to automate covariate-adaptive randomization in REDCap via data entry triggers.JAMIA open · 2025Article
- CONSORT 2025 explanation and elaboration: updated guideline for reporting randomised trials.BMJ (Clinical research ed.) · 2025Article
- Covariate adjustment in Bayesian adaptive randomized controlled trials.Statistical methods in medical research · 2024Article
- The handling of missing data in trial-based economic evaluations: should data be multiply imputed prior to longitudinal linear mixed-model analyses?The European journal of health economics : HEPAC : health economics in prevention and care · 2023Article
- Article
- A scoping review described diversity in methods of randomization and reporting of baseline balance in stepped-wedge cluster randomized trials.Journal of clinical epidemiology · 2023Article
- Recent innovations in adaptive trial designs: A review of design opportunities in translational research.Journal of clinical and translational science · 2023Review
- When randomisation is not good enough: Matching groups in intervention studies.Psychonomic bulletin & review · 2021Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
5 authors.
Funding
Abstract
backgroundIn theory, efficient design of randomized controlled trials (RCTs) involves randomization algorithms that control baseline variable imbalance efficiently, and corresponding analysis involves pre-specified adjustment for baseline covariates. This review sought to explore techniques for handling potentially influential baseline variables in both the design and analysis phase of RCTs.
methodsWe searched PubMed for articles indexed "randomized controlled trial", published in the NEJM, JAMA, BMJ, or Lancet for two time periods: 2009 and 2014 (before and after updated CONSORT guidelines). Upon screening (343), 298 articles underwent full review and data abstraction.
resultsTypical articles reported on superiority (86%), multicenter (92%), two-armed (79%) trials; 81% of trials involved covariates in the allocation and 84% presented adjusted analysis results. The majority reported a stratified block method (69%) of allocation, and of the trials reporting adjusted analyses, 91% were pre-specified. Trials published in 2014 were more likely to report adjusted analyses (87% vs. 79%, p = 0.0100) and more likely to pre-specify adjustment in analyses (95% vs. 85%, p = 0.0045). Studies initiated in later years (2010 or later) were less likely to use an adaptive method of randomization (p = 0.0066; 7% of those beginning in 2010 or later vs. 31% of those starting before 2000) but more likely to report a pre-specified adjusted analysis (p = 0.0029; 97% for those initiated in 2010 or later vs. 69% of those started before 2000).
conclusionWhile optimal reporting procedures and pre-specification of adjusted analyses for RCTs tend to be progressively more prevalent over time, we see the opposite effect on reported use of covariate-adaptive randomization methods.
Indexed as
Identifiers
What Socratic holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.