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Published on: January 19, 2024
Reference Interval Establishment for Four Coagulation Parameters Using Indirect Methods in a High-Altitude Chinese
Banjiu Zhaxi1, Danni Mu1, Shengfang Ye2
1Department of Laboratory Medicine, Peking Union Medical College Hospital, Peking Union Medical College & Chinese Academy of Medical Science, Beijing, China.
Objectives:
This study utilized two indirect methods to establish reference intervals (RIs) for four coagulation parameters for the adult population in Tibet, a high-altitude region in Western China.
Methods:
Coagulation Data, Including Activated Partial Thromboplastin Time (APTT), prothrombin Time (PT), thrombin Time (TT), and Fibrinogen (FIB) Obtained From the People's Hospital of Tibet Autonomous Region Between 2019 and 2023, Were Subjected to Box-Cox Transformation for Normalization and Tukey Method for Outlier Removal. the RIs Were Calculated Using Hoffmann and refineR Methods, Respectively.
Results:
A total of 5086, 5282, 5386, and 5377 test results for APTT, PT, TT, and FIB were included. The Hoffmann and refineR method yielded the following total RIs: APTT 30.54-46.32 and 30.14-44.30 s; PT 10.54-14.51 and 10.32-13.89 s; TT 14.92-19.46 and 14.88-18.93 s; FIB 2.05-4.68 and 2.02-4.40 g/L, respectively. Gender-partitioned RIs were calculated for all four parameters, while age-partitioned RIs were specifically calculated for PT and FIB based on bias ratio values. The lower limits of RIs estimated by the two methods remained consistent. The established RIs for APTT and FIB were significantly higher than those utilized in the plain area and those provided by the manufacturer, whereas the established RIs of TT were significantly lower.
Conclusion:
The RIs for coagulation parameters in the population living on the Tibetan Plateau exhibited significant divergence from those utilized in the plain area. Specific RIs for high-altitude regions should be established to accurately evaluate the presence of coagulation disorders.