Background :Reference values of hematological parameters vary considerably under the influence of different factors, such as age, race, and sex. The aim of this study was to determine the reference values of hematological parameters for primary school children living in Chungnam province. Method :An automated complete blood cell count was performed on a group of school children from Chungnam province. Blood was collected by venipuncture in a 5 mL lavender top tube anticoagulated with EDTA (Vacutainer System, BectonDickinson and Company Rutherford, New Jersey, U. S. A. 1. Blood specimens were analyzed on a Coulter Count Model S-Plus STKR at room temperature within two hours of drawing. These data were statistically analyzed using the SPSS computer program. Result :The reference values obtained were : total leukocyte count, 4.7 to 12.3 x 10^3/uL; red blood cell count, 4.1 to 5.3 X lO^6/uL; hemoglobin, 11.9 to 14.7g/dL; hematocrit, 33.8 to 41.8% ; MCV, 74.8 to 86.8 fL; MCH, 26.1 to 30.9 pg; MCHC, 34.3 to 36.3g/dL; RDW, 11.6 to 14.1%; platelet count, 222 to 519 X 103/pL; and MPV, 6.4 to 9.6 fL. Conclusion :We constructed the reference values of complete blood cell count according to the theory advocated by International Committee for Standardization in Hematology(ICSH) and International Federation of Clinical Chemistry (IFCC) using automated cell counter. So our reference values are adequate for clinical application than those obtained from published value. In the school children, reference values obtained from low grade or high grade group are more adequate for clinical application than those from male or female group.

Keywords: Reference values, Hematological parameters, Complete blood cell count