Haematological profile in healthy urban population (8 to 70 years of age).

Haematological profile for 17 constituents of blood were determined in 998 healthy school children (8-19 years old) and 2246 healthy adult persons (20-70 years old) residing permanently or at least 5 years in a defined geographic region of Zagreb, Croatia. Physiological variations corresponding to age and sex were studied as the most important factors affecting biological variation in haematological constituents of blood. In our study erythrocytes, haemoglobin and haematocrit values were not sex dependent until the age of 13 after which the values were higher in men that in women. Sedimentation rate showed sex and age related differences in the adult age with higher values in women especially after 50 years. Total leukocyte count declined with age and in adults the values were slightly lower in women. Segmented neutrophil granulocytes showed the upward trend with age whereas the lymphocyte and monocyte counts declined. Women showed slightly higher platelet count in the adult age. Based on biological variation, we have estimated the reference intervals for 17 haematological constituents of blood in order to provide medically reliable evaluation of haematological laboratory results.