Cluster randomised controlled trial

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A cluster randomised controlled trial is a type of randomised controlled trial in which groups of subjects (as opposed to individual subjects) are randomised. [1] Cluster randomised controlled trials are also known as cluster randomised trials, [2] group-randomised trials, [3] [4] and place-randomized trials. [5] Cluster-randomised controlled trials are used when there is a strong reason for randomising treatment and control groups over randomising participants. [6]

Contents

Prevalence

A 2004 bibliometric study documented an increasing number of publications in the medical literature on cluster randomised controlled trials since the 1980s. [1]

Advantages

Advantages of cluster randomised controlled trials over individually randomised controlled trials include:

Disadvantages

Disadvantages compared with individually randomised controlled trials include greater complexity in design and analysis, and a requirement for more participants to obtain the same statistical power. [2] Use of this type of trial also means that the experiences of individuals within the same group are likely similar, leading to correlated results. This correlation is measured by the intraclass correlation, also known as the intracluster correlation. Though this correlation is a known component of cluster randomised controlled trials, a large proportion of the trials fail to account for it. Failing to control for intraclass correlation negatively affects both the statistical power and the incidence of Type I errors of an analysis. [6]

See also

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References

  1. 1 2 Bland JM (2004). "Cluster randomised trials in the medical literature: two bibliometric surveys". BMC Med Res Methodol. 4: 21. doi:10.1186/1471-2288-4-21. PMC   515302 . PMID   15310402.
  2. 1 2 Campbell MK, Elbourne DR, Altman DG, CONSORT group (2004). "CONSORT statement: extension to cluster randomised trials". BMJ. 328 (7441): 702–8. doi:10.1136/bmj.328.7441.702. PMC   381234 . PMID   15031246.
  3. Murray DM, Varnell SP, Blitstein JL (2004). "Design and analysis of group-randomized trials: a review of recent methodological developments". Am J Public Health. 94 (3): 423–32. doi:10.2105/AJPH.94.3.423. PMC   1448268 . PMID   14998806.
  4. Patton GC, Bond L, Carlin JB, Thomas L, Butler H, Glover S, Catalano R, Bowes G (2006). "Promoting social inclusion in schools: a group-randomized trial of effects on student health risk behavior and well-being". Am J Public Health. 96 (9): 1582–7. doi:10.2105/AJPH.2004.047399. PMC   1551970 . PMID   16873760.
  5. Boruch R, May H, Turner H, Lavenberg J, Petrosino A, De Moya D, Grimshaw J, Foley E (2004). "Estimating the effects of interventions that are deployed in many places: place-randomized trials". American Behavioral Scientist . 47 (5): 608–633. doi:10.1177/0002764203259291.CS1 maint: discouraged parameter (link)[ permanent dead link ]
  6. 1 2 Murray, David M.; Taljaard, Monica; Turner, Elizabeth L.; George, Stephanie M. (2020). "Essential Ingredients and Innovations in the Design and Analysis of Group-Randomized Trials". Annual Review of Public Health. 41: 1–19. doi: 10.1146/annurev-publhealth-040119-094027 . PMID   31869281.
  7. Edwards SJ, Braunholtz DA, Lilford RJ, Stevens AJ (1999). "Ethical issues in the design and conduct of cluster randomised controlled trials". BMJ. 318 (7195): 1407–9. doi:10.1136/bmj.318.7195.1407. PMC   1115783 . PMID   10334756.
  8. Sampling People, Networks and Records coursers course (worth finding a better reference)

Further reading