Fig. 5

a Forest plot of hazard ratio of CV events VENTS among patients with T2DM at baseline, metformin therapy vs no-metformin therapy. b Forest plot of hazard ratio of CV events among patients without T2DM at baseline, metformin therapy vs no-metformin therapy. c Forest plot of hazard ratio of CV events among patients with metformin monotherapy vs sulphonylurea monotherapy. d Forest plot of hazard ratio of CV events among patients with metformin monotherapy vs no-drug therapy