Fig. 4
Subgroup analysis of the association between restenosis and glycemic control levels. The vertical dashed lines indicate the pooled summary estimate (95% CI) for all studies in Fig. 4 (‘Under Control’ subgroup, RR = 1.53, 95% CI, 1.25–1.62; I2 = 36.9%, P < 0.05, ‘Unknown’ subgroup, RR = 1.37, 95% CI, 1.16–1.63; I2 = 63%, P = 0.001.). The area of each square is proportional to the inverse variance of the estimate. The horizontal lines indicate the 95% confidence intervals of the estimate