Protocol:
We thank all referees from the Cochrane Consumers and Communication Review Group and from the NIVEL, Netherlands Institute for Healthcare Services Research, for their very useful comments on the protocol and the text of the review. We also thank the editors and staff of the Consumers and Communication Review Group; particularly Ms Judy Stoelwinder for her assistance with the search strategy for this review.

We thank NIVEL, the Netherlands Institute for Healthcare Services Research, which provided support to this review in the form of a workstation and email and internet facilities, as well as a budget of 1500 Euro for retrieving papers. The comments and support of the scientific staff of the NIVEL, and especially of Prof. Dr. J. van der Zee and Dr. A.L. Francke, were very welcome.

Review:

• Ms. Judy Stoelwinder, Consumers and Communication Review Group, assisted with the search strategies for this review.

• Ms. Anne Vicky Carlier, Netherlands Institute for Health Care Services Research, performed all interlibrary loans.

• Mr. Rob Scholten, Dutch Cochrane Center, checked the statistical analyses.

• Ms. Atie Schipaanboord commented on the text of the review from the perspective of the Dutch Patients and Consumers Federation.

• Mr. Jouke van der Zee and Ms. Anneke Francke, Director and Program Coordinator of the Netherlands Institute for Health Care Services Research, gave general scientific advice on the review.

• The scientific committee of the Netherlands Institute for Health Care Services Research commented the protocol and the text of the review.

• The editors and staff of the Consumers and Communication Review Group, and especially Dr. Megan Prictor and Dr. Sophie Hill, gave general advice, comments and above all support in writing the protocol and the text of the review.