Fig. 1: Flowchart of the study population.

MM metformin during RCT and extension study, PM placebo during RCT and metformin during extension study, MP metformin during RCT and placebo during extension study, PP placebo during RCT and extension study

MM metformin during RCT and extension study, PM placebo during RCT and metformin during extension study, MP metformin during RCT and placebo during extension study, PP placebo during RCT and extension study