Lizotte Annie, Quessy Isabelle, Vanier Marie-Claude, Martineau Josée, Caron Stéphanie, Darveau Martin, Dubé Alain, Gilbert Edith, Blais Normand, Lalonde Lyne
Cité de la Santé de Laval, Quebec, Canada; Faculty of Pharmacy, University of Montreal, Quebec, Canada.
J Thromb Thrombolysis. 2002 Dec;14(3):247-54. doi: 10.1023/a:1025061129122.
In a pharmacist-managed anticoagulation clinic, portable point-of-care coagulation devices may facilitate patient monitoring by providing rapid INR measurement. Few studies, however, have validated this type of device.
To evaluate the reliability, validity and ease of use of the CoaguChek S, a new portable coagulation device.
A total of 100 patients followed at a pharmacist-managed anticoagulation clinic attended two study visits. INRs were measured using the CoaguChek S and the standard laboratory technique.
Reliability: The test-retest reliability (precision) of the CoaguChek S, estimated by the intraclass correlation coefficient (ICC) and a 95% confidence interval (95% CI), was high (0.98 (0.98-0.99)) and comparable to the standard laboratory technique (0.99 (0.98-0.99)). Interrater reliability was also high (0.97 (0.95-0.98)). Reliability coefficients did not vary with the test-strip lot number nor the CoaguChek S operator.
When compared with standard laboratory procedure, the ICC (95% CI) was equal to 0.93 (0.91-0.95). The mean difference (95% CI) between INR measured by the laboratory and the CoaguChek S was equal to -0.02 units (-0.06-0.03). The mean absolute and relative absolute differences (95% CI) were equal to 0.24 units (0.21-0.27) and 9% (8%-10%), respectively. Differences tended to increase for INRs greater than 3 units as seen by a mean difference (95% CI) of -0.17 units (-0.35-0.02). This represented a mean absolute difference (95% CI) of 0.44 units (0.33-0.55) and a mean relative absolute difference of 12% (9%-15%). Concordance between therapeutic decisions based on CoaguChek S and laboratory results was high (Kappa = 0.68). In 34 cases (18%), the therapeutic decision would have been different. However, in 15 of these discordant observations, the difference between the CoaguCheck S and laboratory INR was <or=0.25 units. Ease of use: In 3% of cases, no INR could be measured by the CoaguChek S. The percentage of extra finger pricks and extra test-strips were equal to 25.8% and 23.7%, respectively.
When used by health professionals in a pharmacist-managed anticoagulation clinic, the CoaguChek S is reliable, valid and easy to use. However, its validity tends to decrease as the INR increases, possibly due to the low sensitivity of the thromboplastin. If the CoaguChek S INR is supratherapeutic, we would therefore recommend confirming the results with a standard laboratory measurement.
在药剂师管理的抗凝门诊中，便携式即时凝血设备可通过快速测定国际标准化比值（INR）来方便患者监测。然而，很少有研究对这类设备进行验证。
评估新型便携式凝血设备CoaguChek S的可靠性、有效性和易用性。
在药剂师管理的抗凝门诊随访的100名患者参加了两次研究访视。使用CoaguChek S和标准实验室技术测量INR。
可靠性：通过组内相关系数（ICC）和95%置信区间（95%CI）估计，CoaguChek S的重测可靠性（精密度）很高（0.98（0.98 - 0.99）），与标准实验室技术相当（0.99（0.98 - 0.99））。评分者间可靠性也很高（0.97（0.95 - 0.98））。可靠性系数不随试纸批号和CoaguChek S操作人员而变化。
与标准实验室程序相比，ICC（95%CI）等于0.93（0.91 - 0.95）。实验室测量的INR与CoaguChek S测量的INR之间的平均差值（95%CI）等于 -0.02单位（-0.06 - 0.03）。平均绝对差值和相对绝对差值（95%CI）分别等于0.24单位（0.21 - 0.27）和9%（8% - 10%）。当INR大于3单位时，差值有增大趋势，平均差值（95%CI）为 -0.17单位（-0.35 - 0.02）。这代表平均绝对差值（95%CI）为0.44单位（0.33 - 0.55），平均相对绝对差值为12%（9% - 15%）。基于CoaguChek S的治疗决策与实验室结果之间的一致性很高（Kappa = 0.68）。在34例（18%）病例中，治疗决策会有所不同。然而，在这些不一致的观察结果中，有15例CoaguCheck S与实验室INR之间的差值≤0.25单位。易用性：在3%的病例中，CoaguChek S无法测量INR。额外手指针刺和额外试纸条的百分比分别为25.8%和23.7%。
当由药剂师管理的抗凝门诊中的卫生专业人员使用时，CoaguChek S可靠、有效且易于使用。然而，随着INR升高，其有效性往往会降低，这可能是由于凝血活酶的敏感性较低。因此，如果CoaguChek S测量的INR高于治疗范围，我们建议用标准实验室测量来确认结果。
