Table 5.

Regression model for GFR estimation: 10-h studies^a

Parameter	Coefficient	95% CI	P
Fixed effects
constant (ml/min/1.73 m2)	58.6	46.4 to 70.8	<0.001
sampling time (h)	−11.7	−14.2 to −9.2	<0.001
sampling time2 (h2)	0.676	0.48 to 0.87	<0.001
eGFR (ml/min/1.73 m2)	0.369	−0.01 to 0.75	0.057
eGFR × sampling time	0.119	0.04 to 0.20	0.003
eGFR × sampling time2	−0.007	−0.013 to −0.001	0.021
Random effects
intercept SD	7.66	5.01 to 11.72
sampling time SD	0.624	0.380 to 1.027
correlation (time, intercept)	−0.85	−0.96 to −0.53
residual SD	2.56	2.22 to 2.96

^aRandom coefficient model with maximal likelihood estimates.