Lee et al. BMC Cancer 2011, 11:20 http://www.biomedcentral.com/1471-2407/11/20 Page 7 of 10 Figure 1 Hazard ratios in metformin-treated type 2 diabetes for cancer incidence for men (n = 8,167). Adjusted for age group, gender, other oral anti-hyperglycemic medication, CCI score, and duration of metformin exposure (a time dependent variable). Reference: Diabetes patients use oral anti-hyperglycemic medication except metformin. Figure 2 Hazard ratios in metformin-treated type 2 diabetes for cancer incidence for women (n = 7,100). Adjusted for age group, gender, other oral anti-hyperglycemic medication, CCI score, and duration of metformin exposure (a time dependent variable). Reference: Diabetes patients use oral anti-hyperglycemic medication except metformin.