Muireann Ni Chroinin reviewed the literature searches from 2002‐2004, identified and reviewed the full‐text publication of all citations of potential or potentially eligible RCTs, extracted the methodology and data, entered the description of studies and data entry in RevMan, analysed and interpreted results of the meta‐analysis and wrote the final review.

Dr Ilana Greestone conceived the protocol, requested the literature search, identified and reviewed the full‐text publication of all citations of potential or potentially eligibible RCTs from 1999‐2001, drafted the correspondance to authors and/or the pharmaceutical companies to solicit their collaboration in this review and to identify other possibly relevant trials, participated in extraction of the methodology and data, entering the description of studies and data entry in RevMan, interpreted results of the meta‐analysis and approved the final review.

Three research assistants participated in some aspects of the review. Helen Magdalinos (May‐July 2001), Alya Danish (November 2001‐March 2002), Vincent Masse (June‐August 2004) participated in the entry of data, references, characteristics of included and excluded studies, and revision of the table of comparisons. Xu Zhang performed and assisted in the interpretation of the meta‐regression.

Francine Ducharme supervised Muireann Ni Chroinin, Ilana Greenstone and the research assistants. She revised the protocol, supervised the literature search, created the methodology and data extraction forms, reviewed all full‐text publications for relevance, participated in the selection of trials, methodology assessment, and data extraction, corresponded with authors and/or the pharmaceutical companies to identify other possibly relevant trials, verify methodology and data extraction and request additional information, supervised the analysis, interpretation, and writing up of the review.