Fig. 1From: Cardiovascular benefits of SGLT2 inhibitors in type 2 diabetes, interaction with metformin and role of erythrocytosis: a self-controlled case series studyIllustration of the self-controlled case series model by metformin and SGLT2i use. The risk periods were patient time divided into four mutually exclusive windows: (i) baseline period which covered the time of metformin use without SGLT2i; (ii) pre-SGLT2i period as the pre-exposure period, which was defined as three months before each initiation of SGLT2i; exposure periods including (iii) SGLT2i use alone period; and (iv) combined use of metformin and SGLT2i period.Back to article page