Perbedaan Nilai Prothrombin Time dan activated Partial Thromboplastin Time pada Sampel Ikterik dengan Metode Optikal dan Metode Elektromekanik

Abstract

Background: Prothrombin time (PT) and activated partial thromboplastin time (aPTT) tests are important screening tests for assessing coagulation pathway function and monitoring anticoagulant therapy. These tests use coagulation analyzers with different detection methods, namely optical and electromechanical methods. The working principles of these two methods can cause variations in test results, especially in samples affected by jaundice. Therefore, it is necessary to evaluate the comparative values of PT and aPTT in jaundiced samples using both methods. Objective: To assess the differences in PT and aPTT values in jaundiced samples using the optical and electromechanical methods. Methods: This study used a cross-sectional design with 69 jaundiced samples at Adam Malik Hospital. PT and aPTT tests were performed using two methods, namely the optical method and the electromechanical method. Data were analyzed using the Mann Whitney test, Kappa test, Spearman correlation test, and Bland Altman test. Results: Significant differences were found in PT and aPTT tests using optical and electromechanical methods (p < 0.001), while INR did not show significant differences (p = 426). In the test of agreement between the interpretation of results using the Kappa test, the agreement was moderate for PT (κ = 0.599; p < 0.001) and strong for aPTT (κ = 0.661; p < 0.001). Despite numerical differences, both methods provided comparable clinical interpretations. The correlation test between total bilirubin and PT and aPTT showed no significant relationship. Conclusion: Optical and electromechanical methods produce comparable clinical interpretations despite differences in PT and aPTT values, and total bilirubin levels are not associated with PT or aPTT results.