Changed items

The following changes to the published protocol with regards to 'types of intervention' were implemented: The following comparisons were acceptable for evaluation: ‐ rosiglitazone versus placebo; ‐ rosiglitazone versus another oral antidiabetic medication (meglitinide analogues, metformin, pioglitazone, sulphonylureas); ‐ rosiglitazone in combination with an oral antidiabetic medication or insulin versus a combination of an oral antidiabetic medication or insulin (agents and treatment schemes had to be identical). Excluded interventions: Combination therapies consisting of different compounds in the treatment arms (for example rosiglitazone plus metformin versus uptitration of metformin or rosiglitazone plus gliclazide versus gliclazide). Another Cochrane review will investigate rosiglitazone‐metformin combination therapies including different treatment regimens of these compounds. Furthermore, dipeptidyl peptidase‐4 (DPP‐4) inhibitors for type 2 diabetes mellitus are excluded, since these are the topic of another Cochrane review (Richter 2007), as well as glucagon‐like peptide analogues for type 2 diabetes mellitus (Cochrane review, Snaith 2007).