Reporting the NAFT Major Bleeding Rates in Context: Reviewers Should Include Site Investigator–Classified Rates

In their article, Strebel and colleagues¹ report a systematic review assessing the relative efficacy and safety of low-molecular-weight heparins used to prevent thrombosis after total hip replacement. The authors comment that for the double-blind North American Fragmin Trial (NAFT),² "This relatively low incidence of thrombosis is offset by a relatively high rate of major bleeding of 8.8% in the early preoperative group and 6.8% in the early postoperative group."¹ The authors further note that "The rates of bleeding in both of these perioperative groups are higher" than their pooled preoperative and postoperative data or the perioperative data reported by Planes et al³ and Francis et al.⁴