Pediatric reference values for calcium, magnesium and inorganic phosphorus in serum obtained from Bhattacharya plots for data from unselected patients.

Pediatric reference values for total calcium, magnesium and inorganic phosphorus are given. The values were determined by using Bhattacharya plots for unselected data. The reference values for calcium (from 8320 values from patients) and magnesium (from 1231 values from patients) show only minor dependence on age. Reference values for ages up to 20 years for calcium were 2.14-2.64 mmol/l and for magnesium 0.57-1.12 mmol/l. However, for inorganic phosphorus (3349 values from patients) a gradual decrease in concentration occurred throughout childhood from 1.56-2.29 mmol/l (less than 1 year) to 1.03-1.78 mmol/l (greater than 15 years).