| Percentage contributions of variance components within-individual | Percentage contributions of variance components between-individual | VR | Mean intake (μg/day) | CV_{w}^{a} (%) | CV_{b}^{b} (%) | D_{1} 10%(days) ^{c} | D_{2} 20%(days) ^{c} | D_{3} r = 0.9 (days)^{d} | D_{4} r = 0.8 (days)^{d} | D_{5} r = 0.5 (days)^{d} |
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Men (n = 98) | 76.3 | 23.7 | 3.2 | 9.80 | 79.1 | 44.0 | 240 | 60 | 14 | 6 | 1 |

Women (n = 142) | 81.2 | 18.8 | 4.3 | 10.21 | 83.0 | 39.9 | 265 | 66 | 18 | 8 | 1 |

All (n = 240) | 79.8 | 20.2 | 3.9 | 10.04 | 81.5 | 41.5 | 255 | 64 | 16 | 7 | 1 |

- CV
_{w}, coefficient of within-individual variation; CV_{b}, coefficient of between-individual variation; VR, ratio of within- to between- individual variance \( \left(\frac{{\hat{\sigma}}_w^2}{{\hat{\sigma}}_b^2}\right) \) ^{a}\( \mathrm{CVw}=\frac{\sqrt{{\hat{\sigma}}_w^2}}{\mathrm{mean}\ \mathrm{acrylamide}\ \mathrm{intake}}\times 100 \)^{b}\( \mathrm{CVb}=\frac{\sqrt{{\hat{\sigma}}_b^2}}{\mathrm{mean}\ \mathrm{acrylamide}\ \mathrm{intake}}\times 100 \)^{c}Number of days needed to lie within specified % of the true means: D_{1.2} = (Z_{α}CV_{w}/E)^{2}, where D = number of days needed per person, Z_{α} = normal deviate (1.96), E = specific error admitted as a percentage of the true usual intake; 10% or 20%^{d}Number of days required to ensure r = 0.9 or 0.8 or 0.5 between observed and true mean intake: \( {\mathrm{D}}_{3,4,5}=\left[\frac{r^2}{\left(1-{r}^2\right)}\right]\times \mathrm{VR} \), where r = the unobservable correlation coefficient between the observed and true mean nutrient intakes of the individual