Study designs of evaluations included in the review
Published randomised controlled trials (RCTs). Crossover or non-crossover, open or blinded with a minimum duration of treatment of 6 weeks.
Specific interventions included in the review
Metformin and sulphonylurea(s) for the treatment of non-insulin dependent diabetes mellitus.
Participants included in the review
Patients with non-insulin dependent diabetes mellitus, either newly presenting or with long-standing diabetes up to 24 years. Age ranged from 36 to 94 years and the majority of patients were overweight.
Outcomes assessed in the review
Glycaemic control (assessed by fasting plasma glucose, random plasma glucose or glycated haemoglobin) and body weight details. Other outcome measures included C-peptide, plasma insulin, serum triglycerides and total cholesterol, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol.
How were decisions on the relevance of primary studies made?
The authors do not state how the papers were selected for the review, or how many of the authors performed the selection.