Optical and Mechanical Clot Detection Methodologies: A Comparison Study for Routine Coagulation Testing

Background: Automated coagulation analyzers are preferred to meet increasing coagulation test volume. Two distinct technological families exist based on optical and mechanical clot detection methodologies. Which one is superior to the other is still a conflict and needs new studies. Methods: We have compared prothrombin and activated partial thromboplastin results obtained with mechanical method with those obtained by photo-optical method used routinely in our specialized laboratory. Results: The instrumental results showed good precision ranging between 0.7% and 1.8% coefficient of variation. Statistical analysis demonstrated an excellent correlation between the photo-optical and mechanical analyzers for PT (R2 0.97), and aPTT (R2 0.85). Conclusion: Correlation between the two clot-detection systems was maintained even when measuring turbid samples (R2 ≥ 0.97 for two tests)