. 2015 Sep 15;124(4):468–476. doi: 10.1289/ehp.1409551

Table 3.

The variance apportionment of log₁₀-transformed creatinine-corrected metal concentrations in urine samples, collected days apart and months apart, from 11 adults.

Type of sample	As	Cd	Co	Cu	Pb	Mo	Ni
Days apart (n = 326)
Spot sample
ICC	0.41	0.64	0.41	0.18	0.10	0.01	0.12
Between persons σ² (%)^a	0.011 (41)	0.047 (64)	0.033 (41)	0.017 (18)	0.018 (10)	0.001 (1)	0.012 (3)
Within person, between day σ² (%)^b	0.015 (56)	0.007 (10)	0.007 (9)	0.012 (12)	0.011 (6)	0.024 (25)	0.107 (31)
Within person, within day σ² (%)^c	0.001 (3)	0.020 (26)	0.041 (50)	0.068 (70)	0.161 (84)	0.070 (74)	0.232 (66)
First morning sample^d
ICC	0.32	0.77	0.74	0.44	0.36	0.01	0.12
Between person σ² (%)^a	0.016 (32)	0.064 (77)	0.077 (74)	0.017 (44)	0.022 (36)	0.001 (1)	0.013 (12)
Within person σ² (%)^b	0.034 (68)	0.019 (23)	0.027 (26)	0.022 (56)	0.040 (64)	0.080 (99)	0.094 (88)
24-hr collection^d
ICC	0.34	0.82	0.69	0.16	0.10	0.06	0.14
Between person σ² (%)^a	0.011 (34)	0.049 (82)	0.040 (69)	0.011 (16)	0.010 (10)	0.002 (6)	0.016 (14)
Within person σ² (%)^b	0.021 (66)	0.011 (18)	0.018 (31)	0.057 (84)	0.089 (90)	0.043 (96)	0.100 (86)
Months apart (n = 265)
Spot sample
ICC	0.21	0.51	0.18	0.01	0.01	0.01	0.01
Between persons σ² (%)^a	0.021 (21)	0.051 (51)	0.019 (18)	0.001 (1)	0.001 (1)	0.001 (1)	0.001 (1)
Within person, between day σ² (%)^b	0.041 (42)	0.021 (21)	0.044 (43)	0.031 (23)	0.048 (25)	0.045 (36)	0.185 (36)
Within person, within day σ² (%)^c	0.036 (37)	0.029 (28)	0.041 (39)	0.102 (76)	0.137 (74)	0.078 (63)	0.318 (63)
First morning sample^d
ICC	0.29	0.59	0.31	0.10	0.11	0.09	0.01
Between person σ² (%)^a	0.024 (29)	0.051 (59)	0.035 (31)	0.011 (10)	0.011 (11)	0.001 (9)	0.001 (1)
Within person σ² (%)^b	0.058 (71)	0.036 (31)	0.078 (69)	0.096 (90)	0.090 (89)	0.113 (99)	0.322 (99)
24-hr collection^d
ICC	0.30	0.65	0.30	0.01	0.01	0.02	0.01
Between person σ² (%)^a	0.021 (30)	0.051 (65)	0.025 (30)	0.001 (1)	0.001 (1)	0.001 (2)	0.001 (1)
Within person σ² (%)^b	0.050 (70)	0.027 (35)	0.058 (70)	0.073 (99)	0.086 (99)	0.054 (98)	0.176 (99)
Days apart: days 0, 1, 2, 3, and 4; months apart: days 0, 30, 60, and 90. σ² = variance. ^aThe proportion of between-person variance to the total variance. ^bThe proportion of within-person between-day variance to the total variance. ^cThe proportion of within-person within-day variance to the total variance. ^dFor first morning and 24-hr urine collections, the distinction between within-day vs. between-day variability is not applicable with only one measurement per day.