Effect of metformin (vs. placebo or sulfonylurea) on all-cause and cardiovascular mortality and incident cardiovascular events in patients with diabetes: an umbrella review of systematic reviews with meta-analysis. - Bahardoust M; Mousavi S; Yariali M; Haghmoradi M; Hadaegh F; Khalili D; Delpisheh A (Journal of diabetes and metabolic disorders, 2023)