All published and unpublished randomized controlled trials that assessed the efficacy of SGAs (aripiprazole, amisulpride, clozapine, olanzapine, quetiapine, risperidone, ziprasidone, and zotepine) in the treatment of mania were searched for in the PsiTri database (http://psitri.stakes.fi) (last search: May 2006). PsiTri is a register of controlled trials that compiles the registers of all Cochrane review groups in the field of mental health. The registers of the single Cochrane review groups are compiled by means of regular searches of numerous electronic databases and conference abstract books and hand searches of major journals (the exact search strategies of the individual review groups are listed in The Cochrane Library10). We also searched MEDLINE. The abstracts, titles, and index terms of studies were searched using the following key words: aripiprazole,amisulpride,clozapine,olanzapine,quetiapine,risperidone,ziprasidone, and zotepine in conjunction with mania,manic, and bipolar. In addition, the reference sections of included articles and key reviews were screened, and the first and last authors (Michael Berk, Charles Bowden, William Carson, Marielle Erdekens, Robert Hirschfeld, Paul Keck, Sumant Khanna, Roger McIntyre, Steven Potkin, Gary Sachs, Mauricio Tohen, Lakshmi Yatham, and John Zajecka) of the included studies and the pharmaceutical companies (AstraZeneca, Eli Lilly, Janssen-Cilag, Bristol-Myers Squibb, and Pfizer) were asked by e-mail between October 1, 2005, and March 31, 2006, whether they were aware of further trials. They were also contacted for the provision of missing data necessary for the meta-analysis. We thank Tohen et al, Yatham et al, McIntyre et al, Smulevich et al, and Bowden et al for sending us additional data. A rating based on the 3 quality categories described in The Cochrane Collaboration Handbook11 was given for each trial: A indicates low risk of bias (adequate allocation concealment); B, moderate risk of bias (some doubt about the results, mainly studies said to be randomized but without an explanation of the method); and C, high risk of bias (clearly inadequate allocation concealment, eg, alternate randomization). Only trials belonging to categories A and B were included. Two of us (H.S. and S.L.) independently extracted data from the trials. Any disagreement was discussed, and the decisions were documented.