title: Comparative study of a portable prothrombin time monitor employing three different systems in oral anticoagulant units.
abstract: The aim of this study was to evaluate the accuracy of the portable coagulometer CoaguChek (Roche Diagnostics) as a prothrombin time (PT) monitor, and to correlate capillary blood results with those of three different routine methods used for monitoring oral anticoagulant therapy (OAT): capillary, plasma and whole blood samples. Three hospitals participated in the study with a total of 235 patients on OAT. The international normalized ratio (INR) results obtained with CoaguChek were compared with those obtained using each of the routine methods. The study presents a good correlation between the PT monitor and the three methods studied: r = 0.9745 (hospital A), r = 0.9283 (hospital B), r = 0.9136 (hospital C). A simplified concordance test of the methods results in a nine-field comparison table showing concordances of 87.2, 85.7 and 68.4%, respectively. The absolute difference (mean +/- SD) between laboratory A and CoaguChek INRs was 0.0571 +/- 0.2042, with values of 0.04286 +/- 0.3906 for laboratory B and 0.6986 +/- 0.6170 for laboratory C. These results confirm that CoaguChek could be used as a new method for oral anticoagulant monitoring, and is in best agreement with the capillary blood PT system.
authors.affiliation: FIDEC Fundación para la Investigación y Docencia de las Enfermedades Cardiovasculares, Facultad de Medicina y Odontología, Universidad del País Vasco/Euskal Herriko Unibertsitatea, Hospital de Basurto, Bilbao, Spain. bdbvarim@lg.ehu.es
authors.forename: M
authors.initials: M
authors.lastname: Vacas
authors.forename: M A
authors.initials: MA
authors.lastname: Fernández
authors.forename: F
authors.initials: F
authors.lastname: Martínez-Brotons
authors.forename: P J
authors.initials: PJ
authors.lastname: Lafuente
authors.forename: F
authors.initials: F
authors.lastname: Ripoll
authors.forename: C
authors.initials: C
authors.lastname: Alvarez
authors.forename: J A
authors.initials: JA
authors.lastname: Iriarte
mesh_terms: D006801:Humans; D019934:International Normalized Ratio; D018670:Monitoring, Ambulatory / Q000295:instrumentation* / Q000592:standards*; D011517:Prothrombin Time; D012044:Regression Analysis; D015203:Reproducibility of Results