INS and type 2 diabetes mellitus: Further analysis showed that the higher CCI score among the Medical-aid group than the higher income group was persistently found, not only among patients in the insulin use group (9.8% vs. 9.2%, P < 0.0001) but also in patients in the oral antidiabetic drug group (5.7% vs. 4.8%, P < 0.0001) and those in the non-use of antidiabetic drug T2DM group (3.7% vs. 2.5%, P < 0.0001).