Extending the CONSORT statement to cluster randomized trials: for discussion

The need for clear reporting of randomized controlled trials has been empha sized recently. The CONSORT Statement has made evidence-based suggestions f or a checklist and a patient flow diagram. Adapting this for cluster random ized controlled trials presents particular challenges. Simple changes in th e checklist and diagram for the completely randomized two level cluster ran domized trials are suggested for discussion. An example taken from an unpub lished trial demonstrates that these changes are less simple to implement, although extensions to electronic publications may be helpful. These sugges tions should be formally evaluated. Further work is required to consider th e cases of more levels and of stratified or pair-matched cluster randomized trials. Copyright (C) 2001 John Wiley gr Sons, Ltd.