Table 5.

Comparison between measured corrected TCa and predicted corrected TCa values derived from the four previously reported formulas and the approximated corrected TCa in patients with CKD G4 + G5 and CKD G5D, respectively

	Measured corrected TCa	Payne	Jain	Portale	Ferrari	New formula
G4 + G5
Mean ± SD, mg/dl	9.34 ± 0.81	8.99 ± 0.82*	8.10 ± 0.78*	8.90 ± 0.78*	9.24 ± 1.10**	9.32 ± 0.84
ICC		0.576	0.652	0.652	0.377	0.826
95% CI		0.545–0.605	0.626–0.677	0.626– 0.677	0.338– 0.415	0.812– 0.840
G5D
Mean ± SD, mg/dl	9.32 ± 0.97	9.43 ± 1.01	8.44 ± 0.99*	9.24 ± 0.99	9.98 ± 1.25*	9.33 ± 1.00
ICC		0.766	0.504	0.803	0.480	0.850
95% CI		0.719–0.807	0.420–0.579	0.762– 0.838	0.394– 0.558	0.818– 0.877

CI = Confidence interval; SD = standard deviation.

^*p < 0.001 and

^**p < 0.05 vs. measured corrected TCa.