Use of covariates in randomized controlled trials
Open accessAbstract
A recent discussion in this journal illustrates some recurrent misunderstandings about the role of covariates in randomized controlled trials (RCTs). This letter aims at clarifying this role and at pointing out a pitfall in SPSS repeated measures ANOVA. We hope that our commentary will contribute to a further improvement in the use of advanced statistics in neuropsychology.
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The use of covariates in a study design such as this is not a sound strategy.
“detailed statistical arguments as to why the use of covariates in a study design such as ours is not a sound strategy.”
From The effect of risk communication on periodontal treatment outcomes: A randomized controlled trial. (2019) · cites this paper as [20]
The paper does not argue that using covariates in randomized controlled trials is unsound. In its discussion of baseline differences, it says covariates can increase the power of a treatment-effect test, although they are not needed to correct chance baseline differences. The citing sentence does not specify what differs about its own design, so the paper cannot establish a blanket judgment about that design. (LLM, conf=0.88)
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- Authors
- VAN BREUKELEN, G. J. P., & VAN DIJK, K. R. A.
- Venue
- Journal of the International Neuropsychological Society
- Publisher
- Cambridge University Press (CUP)
- Published
- 2007-08-14
- Volume
- 13
- Issue
- 5
- Pages
- 903-904
- ISSN
- 1355-6177 (ISSN-L)
- 1469-7661
- OpenAlex
- W2155859251
- Cited by
- 78
- References
- 0
- Citations by year
- 2025: 6 · 2024: 4 · 2023: 4 · 2021: 4 · 2020: 6 · 2019: 4 · 2018: 4 · 2017: 6 · 2016: 2 · 2015: 12 · 2014: 4 · 2013: 4 · 2012: 5
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- Journal of the International Neuropsychological Society (publishedVersion)
- PubMed (publishedVersion)
- Research Publications (Maastricht University) (publishedVersion, other-oa)
- Research Publications (Maastricht University) (submittedVersion, other-oa)
- Topics
- Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Clinical Trials
- Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods and Bayesian Inference
- Social Sciences › Decision Sciences › Statistics, Probability and Uncertainty › Meta-analysis and systematic reviews
- Keywords
- covariates, randomized controlled trials, repeated measures ANOVA, SPSS, neuropsychological research, statistical analysis
- MeSH terms
- Analysis of Variance, Clinical Trials as Topic, Data Interpretation, Statistical, Humans, Randomized Controlled Trials as Topic
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