Table 4.

Sampling duration and GFR estimates stratified by eGFR for 10-h GFR^a

Sampling Duration	Mean GFR (ml/min/1.73 m²)	95% CI	Ratio Compared to 10-h GFR	95% CI of Ratio	P
eGFR stratum >30 ml/min/1.73m²
10 h	40.3	33.2 to 48.9
9 h	41.2	34.1 to 49.8	1.02	0.92 to 1.14	>0.2
8 h	42.1	34.8 to 50.9	1.04	0.94 to 1.16	>0.2
7 h	43.7	36.1 to 52.8	1.08	0.97 to 1.21	0.15
6 h	45.2	37.4 to 54.7	1.12	1.01 to 1.25	0.037
5 h	47.2	39.0 to 57.1	1.17	1.05 to 1.31	0.004
4 h	49.3	40.7 to 59.6	1.22	1.10 to 1.36	<0.001
3 h	53.1	43.8 to 64.4	1.32	1.18 to 1.48	<0.001
2.5 h	56.7	46.9 to 68.6	1.41	1.26 to 1.57	<0.001
2 h	62.3	51.5 to 75.3	1.54	1.39 to 1.72	<0.001
eGFR stratum <30 ml/min/1.73m²
10 h	22.2	18.4 to 26.9
9 h	23.6	19.5 to 28.6	1.06	0.96 to 1.18	>0.2
8 h	24.8	20.5 to 30.0	1.12	1.01 to 1.24	0.037
7 h	25.9	21.4 to 31.3	1.16	1.05 to 1.29	0.004
6 h	27.5	22.7 to 33.3	1.24	1.12 to 1.37	<0.001
5 h	30.3	25.0 to 36.6	1.36	1.23 to 1.51	<0.001
4 h	33.4	27.6 to 40.4	1.50	1.36 to 1.67	<0.001
3 h	39.4	32.5 to 47.8	1.77	1.59 to 1.98	<0.001
2.5 h	44.6	36.9 to 54.0	2.01	1.81 to 2.23	<0.001
2 h	50.2	41.5 to 60.7	2.26	2.04 to 2.51	<0.001

↵^a Mean GFR calculated using a nominal mixed model with maximal likelihood estimates.