© American Society for Clinical Pathology Indirect Estimation of Pediatric Between-Individual Biological Variation Data for 22 Common Serum

Objectives: Derivation of between-individual biological variation (CVg) data requires repeat sampling of the same subject, which is undesirable and challenging in children. We describe an indirect sampling (data mining) approach to obtain these data in children. Methods: Twenty-two serum biochemistry results from 6,989 children, who visited their primary care physician in Queensland, Australia, and were tested only twice within a year were included. The CVg and index of individuality of the boys and girls were estimated by year of age, according to the procedures recommended by Fraser and Harris. Results: The CVg was generally higher during the first year of life and declined to reach a constant level by age 4 to 6 years, except for aspartate aminotransferase, alanin