Fig. 7

Age-stratified estimates for pre-existing conditions extracted from the single studies. Due to differences in the age groups, the estimates were not pooled. Age groups are illustrated in each column as reported in the primary studies. Panel A illustrates single-study estimates for younger age groups. Panel B gives the estimates for older age groups. The error bars represent 95% confidence intervals. The dashed line indicates 1.0 value. The estimates with error bars crossing the 1.0-line lack statistical significance