Reference Intervals for Hemoglobin and Age- and Gender-Related Trends in the Population of Southwest China

Background: The establishment of a proper reference range is necessary for both the prognosis and diagnosis of clinical disease. Our study aimed to establish the hemoglobin reference interval for the population of Southwest of China and to compare this with published data for other races. Methods: A total of 21085 healthy individuals (11561 men and 9524 women, age range 18 - 100 years) living in Southwest China were selected. CBC was performed on an XE-2100 hematology analyzer. The medians were calculated and reference values were determined at the 2.5th and 95th percentiles. Results: There was a statistically significant gender difference for RBC count, Hb, and MCV (p = 0.000). The comparison of Hb by gender showed higher values among males, with lower values in females and this difference was similar to the values for RBC count and MCV. For males, mean values for fib and RBC decreased with age. However, mean values for fib in females increased after middle age. Conclusions: Reference intervals for major red blood cell parameters established in this study showed significant gender differences. For males, mean values for Hb and RBC decreased with age. This is the first region-wide population study on hematologic reference values among people in Southwest China.