Practical considerations for sample size calculation for cluster randomized trials Article Swipe
Clémence Leyrat
,
Sandra Eldridge
,
Monica Taljaard
,
Karla Hemming
·
YOU?
·
· 2024
· Open Access
·
· DOI: https://doi.org/10.1016/j.jeph.2024.202198
YOU?
·
· 2024
· Open Access
·
· DOI: https://doi.org/10.1016/j.jeph.2024.202198
Cluster randomized trials are an essential design in public health and medical research, when individual randomization is infeasible or undesirable for scientific or logistical reasons. However, the correlation among observations within clusters leads to a decrease in statistical power compared to an individually randomised trial with the same total sample size. This correlation - often quantified using the intra-cluster correlation coefficient - must be accounted for in the sample size calculation to ensure that the trial is adequately powered. In this paper, we first describe the principles of sample size calculation for parallel-arm CRTs, and explain how these calculations can be extended to CRTs with cross-over designs, with a baseline measurement and stepped-wedge designs. We introduce tools to guide researchers with their sample size calculation and discuss methods to inform the choice of the a priori estimate of the intra-cluster correlation coefficient for the calculation. We also include additional considerations with respect to anticipated attrition, a small number of clusters, and use of covariates in the randomisation process and in the analysis.
Related Topics
Concepts
Sample size determination
CRTS
Statistics
Cluster (spacecraft)
Computer science
Cluster randomised controlled trial
Sample (material)
Covariate
Correlation
Statistical power
A priori and a posteriori
Econometrics
Randomized controlled trial
Mathematics
Medicine
Philosophy
Chemistry
Epistemology
Geometry
Computer graphics (images)
Surgery
Programming language
Chromatography
Metadata
- Type
- article
- Language
- en
- Landing Page
- https://doi.org/10.1016/j.jeph.2024.202198
- OA Status
- hybrid
- Cited By
- 13
- References
- 49
- Related Works
- 10
- OpenAlex ID
- https://openalex.org/W4391787823
All OpenAlex metadata
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- OpenAlex ID
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https://openalex.org/W4391787823Canonical identifier for this work in OpenAlex
- DOI
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https://doi.org/10.1016/j.jeph.2024.202198Digital Object Identifier
- Title
-
Practical considerations for sample size calculation for cluster randomized trialsWork title
- Type
-
articleOpenAlex work type
- Language
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enPrimary language
- Publication year
-
2024Year of publication
- Publication date
-
2024-02-01Full publication date if available
- Authors
-
Clémence Leyrat, Sandra Eldridge, Monica Taljaard, Karla HemmingList of authors in order
- Landing page
-
https://doi.org/10.1016/j.jeph.2024.202198Publisher landing page
- Open access
-
YesWhether a free full text is available
- OA status
-
hybridOpen access status per OpenAlex
- OA URL
-
https://doi.org/10.1016/j.jeph.2024.202198Direct OA link when available
- Concepts
-
Sample size determination, CRTS, Statistics, Cluster (spacecraft), Computer science, Cluster randomised controlled trial, Sample (material), Covariate, Correlation, Statistical power, A priori and a posteriori, Econometrics, Randomized controlled trial, Mathematics, Medicine, Philosophy, Chemistry, Epistemology, Geometry, Computer graphics (images), Surgery, Programming language, ChromatographyTop concepts (fields/topics) attached by OpenAlex
- Cited by
-
13Total citation count in OpenAlex
- Citations by year (recent)
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2025: 8, 2024: 5Per-year citation counts (last 5 years)
- References (count)
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49Number of works referenced by this work
- Related works (count)
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10Other works algorithmically related by OpenAlex
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