Summary odds ratio of postoperative bacterial infection derived from the univariate (unadjusted) results of observational68,70,78,80,82 and experimental4,83 clinical studies comparing recipients of similar volumes of allogeneic or autologous blood.20 

For each study, the figure shows the OR of postoperative bacterial infection in recipients of allogeneic (compared with autologous) blood. The data from the experimental studies4 83 depicted here represent observational comparisons restricted to patients receiving similar volumes of allogeneic or autologous blood (see text). Each OR is surrounded by its 95% CI. If the 95% CI of the OR includes the null value of 1, the TRIM effect is not statistically significant. The data are plotted on a logarithmic scale extending from 0.1 to 1000.