Table 5.

Comparison of the difference between the medians in the groups of subjects stratified by age and sex (Mann-Whitney test).

Variable	Two-tailed probability
iFGF23 (1-6 years) vs iFGF23 (7-12 years)	P = 0,5183
iFGF23 (1-6 years) vs iFGF23 (13-18 years)	P = 0,7562
iFGF23 (7-12 years) vs iFGF23 (13-18 years)	P = 0,3404
iFGF23 Males vs iFGF23 Females	P = 0,3429
iFGF23 (1-6 years) Females vs iFGF23 (7-12 years) Females	P = 0,5050
iFGF23 (1-6 years) Females vs iFGF23 (13-18 years) Females	P = 0,1967
iFGF23 (7-12 years) Females vs iFGF23 (13-18 years) Females	P = 0,9199
iFGF23 (1-6 years) Males vs iFGF23 (7-12 years) Males	P = 0,2335
iFGF23 (1-6 years) Males vs iFGF23 (13-18 years) Males	P = 0,6888
iFGF23 (7-12 years) Males vs iFGF23 (13-18 years) Males	P = 0,4450