INS and metabolic syndrome: Table 6 listed the top 10 keywords for each cluster. Table 7 listed the ranking of the top 10 keywords according to their frequency. 4 of the top 10 keywords were clustered in the red cluster. The top 3 keywords were “coronary heart disease (n=1641)”, “polycystic ovary syndrome (n=1614)”, and “insulin-resistance (n=1090)”. Figure 7B shows that the hot research directions of CHD and PCOS in recent ten years were oxidative stress, fatty liver-disease, primary prevention, estrogen plus progestin, insulin sensitivity, genome-wide association, metabolism, and dyslipidemia, et al.