TITLE:
Comparative Evaluation of Bovine-Brain-Derived Thromboplastin versus Commercial Thromboplastin Reagents for Prothrombin Time and INR: A Pilot Experimental Study at National Polytechnic University Institute Medical Laboratory
AUTHORS:
Lukong Hubert Shalanyuy, Fonyuy Husein Ali, Wam Elvis Chongsi, Romi Tungleh Toboh, Emmanuel Foncham
KEYWORDS:
Hemostasis, Prothrombin Time, International Normalized Ratio, International Sensitivity Index, Bovine-Brain-Derived Thromboplastin, Commercial Thromboplastin Reagents
JOURNAL NAME:
Open Access Library Journal,
Vol.13 No.8,
August
26,
2026
ABSTRACT: Hemostasis is a vital physiological process, and the Prothrombin Time (PT) test with International Normalized Ratio (INR) is central to monitoring coagulation. Variability in PT/INR results persists due to differences in thromboplastin reagents, with bovine-brain-derived thromboplastin widely used in resourcelimited laboratories for affordability, but associated with lower sensitivity and batch-to-batch variability. Commercial reagents provide greater consistency but are costly. Comparative evaluation is essential to ensure accuracy, reproducibility, and patient safety. The main purpose of this study was to evaluate the analytical performance of bovine-brain-derived thromboplastin compared to commercial thromboplastin reagents for PT and INR testing, focusing on accuracy, precision, reproducibility, concordance of INR values, and International Sensitivity Index (ISI) calibration. An experimental study design was employed at National Polytechnic University Institute Bamenda, Cameroon. Plasma samples from 10 participants were analyzed using both bovine-brain-derived and commercial thromboplastin reagents. A convenience sampling technique was used to include participants. Laboratory procedures followed standardized protocols for reagent preparation, calibration, and PT/INR testing. Data were analyzed using Microsoft Excel 2013, and SPSS version 20.0 with descriptive statistics (mean, standard deviation, coefficient of variation) and agreement analysis (Pearson correlation). The bovine brain derived reagent produced a mean PT of 118.9 seconds (SD 77.4; CV 65.1%), while the commercial reagent yielded a mean PT of 63.0 seconds (SD 41.2; CV 65.4%). Reproducibility was wider with the bovine reagent (27 - 254 s) compared to the commercial reagent (18 - 165 s). Logarithmic transformation reduced dispersion but did not eliminate discrepancies, with weak correlation (r ≈ 0.305, p ≈ 0.392). The estimated ISI for the bovine reagent was 0.369 compared to 1.2 for the commercial reagent, indicating markedly lower sensitivity. This study confirms that bovine-brain-derived thromboplastin, while affordable and accessible, exhibits poor accuracy, precision, and reproducibility compared to commercial reagents. Commercial thromboplastin reagents provide values closer to expected norms, making them more suitable for routine PT/INR testing and anticoagulation monitoring.