Hematological studies by several Brazilian and other Latin-American authors who give parameters considered as normal for different populations have been reviewed. Results showed significant differences, due to social, environmental and nutritional factors as well as to different methodological procedures and also to age, sex, race, occupation and other individual characteristics. Three Brazilian studies were selected in the light of the wide variety of parameters included. Ranges are presented as a demonstration of the variations in such samples, presumably considered "normal" by the respective authors presumably "normal". One of the purposes of the present study is to establish the basis for future investigation into the effects of industrialization on the ranges of the hematological parameters of individuals taken to be normal.
Hematologic tests; Population; Socio-economic factors; Reference values