Sex-Specific Reference Intervals and Age-Related Variations in Hematologic Parameters in Korean Adults Measured Using the Beckman Coulter DxH 900 Analyzer

Background: This study established sex-specific reference intervals (RIs) for hematological parameters, including the monocyte distribution width (MDW), in Korean adults and assessed the need for separate RIs according to sex in older adults.Methods: Hematological parameters were measured using a DxH 900 hematology analyzer (Beckman Coulter, USA) on 328 peripheral blood samples from 124 men and 204 women aged 19-93 years.Results: The RIs for white blood cells, red blood cells (RBCs), Hb, Hct, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, monocyte percentage, and neutrophil, eosinophil, lympho cyte, and monocyte counts differed significantly by sex (P<0.05).Mean corpuscular volume was significantly positively associated with age, whereas RBC and platelet counts were significantly negatively correlated with age in both men and women.Age-based analysis revealed significant shifts in the RBC parameters beginning at 60 years of age in men and 70 years of age in women.The MDW did not show significant differences according to sex or age.Conclusions: This study supports the use of sex-specific RIs and highlights the importance of considering age when interpreting results regarding hematological parameters in clinical practice.