TABLE 1.
Model-derived retinol kinetic parameters for 3 groups of young children1
| Parameter | Bangladesh | Philippines | Guatemala |
|---|---|---|---|
| DT(3), d | 0.206 | 0.206 | 0.206 |
| L(4,3), d−1 | 0.8 | 0.8 | 0.8 |
| L(0,3), d−1 | 0.2 | 0.2 | 0.2 |
| L(5,4), d−1 | 2.15 | 1.22 | 1.22 |
| L(7,5), d−1 | 13.9 | 3.07 | 3.07 |
| L(5,7), d−1 | 1.59 | 0.340 | 0.340 |
| L(6,5), d−1 | 12.3 | 12.3 | 12.3 |
| L(5,6), d−1 | 0.0217 | 0.00884 | 0.00884 |
| L(10,6), d−1 | 0.00246 | 0.00194 | 0.00108 |
| L(8,5), d−1 | 1.30 | 2.21 | 1.34 |
| DT(8), d | 0.052 | 0.052 | 0.052 |
| L(10,8), d−1 | 1 | 1 | 1 |
Values are model-predicted fractional transfer coefficients [L(I, J)s, or the fraction of retinol in compartment J transferred to compartment I each day] and delay times [DT(I)s, or delay time spent in compartment I] determined for geometric mean data sets for Bangladeshi, Filipino, and Guatemalan children using the model shown in Figure 1. For the Filipino and Guatemalan groups, results were calculated using a partially parallel model in which values for the following parameters were set equal between groups: DT(3), L(5,4), L(7,5), L(5,7), L(6,5), and L(5,6). For the Bangladeshi group, values for DT(3) and L(6,5) were set equal to those in the other 2 groups but values for L(5,4), L(5,6), L(7,5), and L(5,7) were independent and adjustable in the model. For all 3 groups, L(10,6) was adjustable and independent. In addition, L(8,5) was fixed for each group at the value calculated to be 50% of the disposal rate/M(5) (see Methods) and DT(8) was fixed at 75 min. See Supplemental Table 2 for corresponding statistical uncertainties for parameters.