Figure 1

Partially corrected meta-analysis of postoperative blood loss in the three trials included by Jacob and colleagues comparing tetrastarch with albumin [ 3 ]. Upon request, individual patient postoperative blood loss data were supplied by Niemi and colleagues [6] and the means and standard deviations of cumulative 24-hour postoperative blood loss by Choi and colleagues [7]. The data provided by Niemi and colleagues reveal that the true blood loss difference in their trial was 41 ml, not 95 ml as imputed by Jacob and colleagues. Both groups in the trial by Hanart and colleagues received albumin postoperatively [8], while Choi and colleagues infused tetrastarch in both groups postoperatively. Reliable correction for confounding in those two trials is not feasible, so these data are subject to bias in favor of tetrastarch. Test fluid administration was limited to the postoperative period in the trial of Niemi and colleagues. Data combined under a fixed-effects model. Error bars indicate 95% confidence interval (CI). Data points scaled according to meta-analytic weight. SD, standard deviation; SMD, standardized mean difference.