RESUMEN
INTRODUCTION: Sample stability is essential to obtain reliable results in the clinical laboratory. This study was conducted to investigate the reliability of hematological parameters using ABX Pentra 60 in samples stored for up to 72 hours at different temperatures. METHODS: A total of 651 blood samples were analyzed at different analysis times: 2, 24, 48, and 72 hours and forms and storage: room temperature (25°C) and at 4°C. The imprecision of the results was evaluated by the analytical coefficient of variation (CVa%) obtained by the typical error (TE) and Kruskal-Wallis analysis, to compare the averages. The reliability of the results was evaluated by the CVa (%) within the maximum allowable analytical variation and by the difference of means of the results in relation to the baseline sample (2 hours). RESULTS: Red blood count, hemoglobin, and MCH parameters showed stability up to 72 hours at room temperature and at 4°C. The other complete blood count parameters showed imprecision results emitted by the ABX Pentra 60 from 24 hours of sample storage, independent of the storage temperature. In addition, there were significant oscillations in the mean values, particularly for the samples stored at room temperature, with the exception of platelet parameters that exhibited mean changes also at 4°C. CONCLUSION: The results demonstrate the importance of the clinical analyst's knowledge about the behavior of the CBC parameters over time under different storage conditions, and mainly the imprecision of the hematological equipment used, for the suitable interpretation of the results.