An Assessment Of An Amidolytic Assay For Factor VII In The Laboratory Control Of Oral Anticoagulants

An amidolytic assay for factor VII, modified from the method of Seligsohn et al (1978), has been compared with the results of the prothrombin time using British Comparative Thromboplastin, Thronbotest and a clotting assay for factor VII. In ‘long-term’ oral anticoagulant administration agreement with the conventional methods was good and better than in our previous study when amidolytic assays for factors II and X respectively were studied (Latallo et al 1981). The method appeared to be reasonably specific for factor VII.

On the present evidence the chromogenic assay for factor VII offers a limited but apparently dependable guide to dosage but it is elaborate to perform and difficult to standardise. The main limiting factor for its routine application is the need to prepare a purified factor X extract.

• 1 Latallo ZS, Thomson. Jean M, Poller L. 1981; Brit. J. Haemat 47: 307-3l8
• 2 Seligsohn U, Østerud B, Rapaport SI. 1978; Blood 52: 978-988