An Antithrombin III assay based on factor Xa inhibition provides a more reliable test to identify congenital antithrombin III deficiency than an assay based on thrombin inhibition - Demers, C; Henderson, P; Blajchman, M A; Wells, M J; Mitchell, L; Johnston, M; Ofosu, F A; Fernandez-Rachubinski, F; Andrew, M; Hirsh, J; Ginsberg, J S (Thromb Haemost, 1993)