Figure 2.

Forest plot of the meta-analysis estimating the hazard ratios and 95%CI of overall survival for older (a) and younger (b) patients assigned to intervention treatment, compared with those assigned to control treatment, by age. Squares represent study-specific HRs, and the size of square represents the weight of individual study included in the meta-analysis. Horizontal lines crossing the square indicate the 95% CIs. The dashed vertical lines indicate the age-specific pooled HR. Diamonds indicate the estimated overall effect according to meta-analysis random effect of pooled HRs from all included studies, calculated separately in younger and older patients, with their corresponding 95%CIs. The p value for heterogeneity is from the meta-analysis of the interaction HRs and represents heterogeneity by patients' age.