Reference Population Expected Rates: CDC Criteria for Anemia

Reference Population Expected Rates: CDC Criteria for Anemia
Anemia is defined as a hemoglobin concentration or hematocrit less than the 5th percentile of the distribution in a non-iron deficient reference population specific for age, sex, and stage of pregnancy for women and age and sex for children.

The reference population for anemia was based on the third National Health and Nutrition Examination Survey (NHANES III), which excluded persons who had a high likelihood of iron deficiency. Age, sex, and stage of pregnancy specific hemoglobin and hematocrit cutoff values for anemia are based on the 5th percentile from NHANES III for both children and women. In the reference population about 5 percent of the population is expected to fall below the 5th percentile for anemia due to normal biologic variation. Prevalence of anemia greater than the expected 5 percent based on the reference population may indicate that anemia is a health problem in the population.