title: Biological and analytical variation of commonly determined blood constituents in healthy blood donors.
abstract: The relative contributions of analytical error and non-systematic biological variation to the reference range for 19 commonly-determined blood chemistry values have been estimated during the course of studying 1000 healthy blood donors. Estimates of non-systematic biological variations are arrived at by determining the variation found in donors matched for factors known to affect blood chemistry such as age and sex, and deducting the within-batch analytical error which applied. Comparison of the within-batch and between-batch analytical precision with the biological variation showed that the percentage increases in the normal range attributable to between-batch analytical error varies between 1 and 29%. This contribution is particularly large in the case of the electrolytes and amounts to no less than 29% in the case of calcium. Apart from well-known relationships a remarkable lack of correlation between the concentration of the different constituents in health is demonstrated.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001774:Blood Chemical Analysis; D001782:Blood Donors; D002118:Calcium / Q000097:blood; D002245:Carbon Dioxide / Q000097:blood; D002712:Chlorides / Q000097:blood; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D008297:Male; D008722:Methods; D008875:Middle Aged; D010710:Phosphates / Q000097:blood; D011188:Potassium / Q000097:blood; D011786:Quality Control; D012709:Serum Albumin / Q000032:analysis; D012964:Sodium / Q000097:blood; D013223:Statistics as Topic
chemical_list: D002712:Chlorides; D010710:Phosphates; D012709:Serum Albumin; D002245:Carbon Dioxide; D012964:Sodium; D011188:Potassium; D002118:Calcium