Study designs of evaluations included in the review
Randomised controlled trials (RCTs) were eligible for inclusion in the review.
Specific interventions included in the review
Studies that compared antithrombin concentrate with placebo were eligible for inclusion. The included studies used different regimens of antithrombin concentrate over 4 or 5 days (details were reported). Two studies did not administer concomitant prophylactic heparin treatment (in these studies a supranormal antithrombin level was achieved in the treatment group); in the third study concomitant heparin was given and a normal antithrombin level was achieved.
Participants included in the review
Studies of patients with severe sepsis and DIC or plasma antithrombin levels less than 70% were eligible for inclusion. The review also included studies with subgroups of participants that met these inclusion criteria. The review included patients with DIC who presented with severe shock, patients with severe sepsis or postsurgical complications with antithrombin levels less than 70%, and a subgroup of patients with severe sepsis in whom the diagnosis of DIC was made post hoc.
Outcomes assessed in the review
Studies reporting mortality were eligible for inclusion. The review primarily assessed death from any cause, but death from specific complications such as major bleeding were also reported. Deaths were assessed at 28 or 30 days post-intervention.
How were decisions on the relevance of primary studies made?
The authors did not state how the papers were selected for the review, or how many reviewers performed the selection.