The reproduction and results of Quick's method with tissue thromboplastin (Kirov Institute of Hematology and Blood Transfusion--KIHBT) and Excel and Excel S simplastins (Organon Teknika, Netherlands) in the tube and automated versions were compared. Semiautomated coagulometer COAG-A-MATE XM and automated COAG-A-MATE RA-4 of the same firm were used. Three Verifi plasmas (Organon Teknika) with different activities of factors II, VII, IX, and X were used. Tests with thromboplastin manufactured by KIHBT were well reproduced both in the tube and automated modifications (CV < 10%). This thromboplastin can be used for monitoring the efficiency of therapy by indirect anticoagulants. For evaluating the correlation between results, plasma samples from 21 donors and 12 patients treated by indirect anticoagulants with the prothrombin index (PI) lower than 75% were analyzed. The PI of the tube and automated modifications were in good correlation. Tests with the Russian thromboplastin showed high coefficients of correlation between the two modifications of Quick's test, which recommends the use of these device-reagent combinations for evaluation of PI.