Different types of cluster membership in parallel-group cluster-randomised trials, where the clusters are institutions: a classification system to aid identification, with six proposed designs
Implications of distinctions between the six types of cluster membership for the statistical analysis require further research. CONSORT guidance needs updating to include specific guidance on reporting the type of cluster membership alongside the description of how design features apply to clusters. Further methodological research is required into both the statistical and the practical implications of adopting previously unlabelled but frequently used types of cluster membership.
Authors
- Claire Surr (ORCID: https://orcid.org/0000-0002-4312-6661)
- Rebecca Walwyn (ORCID: https://orcid.org/0000-0001-9120-1438)
- Amanda Farrin (ORCID: https://orcid.org/0000-0002-2876-0584)
- Andrew J Copas (ORCID: https://orcid.org/0000-0001-8968-5963)
- Alys Wyn Griffiths (ORCID: https://orcid.org/0000-0001-9388-9168)
- Laura Marsden (ORCID: https://orcid.org/0000-0003-3186-2079)
Institutions
- University of Leeds (GB)
- University of Liverpool (GB)
- MRC Clinical Trials Unit at UCL (GB)
- Leeds Dental Hospital (GB)
- University College London (GB)
- Leeds Beckett University (GB)
Publication Details
- Journal
- Trials
- Published
- 2025-09-29
- DOI
- https://doi.org/10.1186/s13063-025-09066-4
- Primary Topic
- Health Systems, Economic Evaluations, Quality of Life
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Medical Research Council