BMJ  2004;328:702-708 (20 March), doi:10.1136/bmj.328.7441.702

Education and debate

CONSORT statement: extension to cluster randomised trials

¹ Health Services Research Unit, University of Aberdeen, Aberdeen, AB25 2ZD, ² Medical Statistics Unit, London School of Hygiene and Tropical Medicine, London, ³ Centre for Statistics in Medicine, Oxford

The first 150 words of the full text of this article appear below.

Reports of cluster randomised trials require additional information to allow readers to interpret them accurately

The effective reporting of randomised controlled trials has received useful attention in recent years. Many journals now require that reports conform to the guidelines in the Consolidated Standards of Reporting Trials (CONSORT) statement, first published in 1996¹ and revised in 2001.² The statement includes a checklist of items that should be included in the trial report. These items are evidence based whenever possible and are regularly reviewed.³ The statement also recommends including a flow diagram to show the flow of participants from group assignment through to the final analysis.

The CONSORT statement focused on reporting parallel group randomised trials in which individual participants are randomly assigned to study groups. However, in some situations it is preferable to randomly assign groups of individuals (such as families or medical practices) rather than individuals. Reasons include the threat . . . [Full text of this article]

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Rapid Responses:

Read all Rapid Responses

CONSORT statement: extension to cluster randomised trials – non-specific effects of control arms may hinder generalisability of results.

Amina Pasquarella, et al.
bmj.com, 23 Mar 2004 [Full text]

Reporting of cluster randomised trials when used in meta-analyses

James M Thomas, et al.
bmj.com, 26 Mar 2004 [Full text]

Is the intraclass correlation enough?

Paul B Silcocks
bmj.com, 11 Aug 2004 [Full text]