Table 7.
PK Model Parameter Estimates for a Typical Infant (Fixed Effects)
| Model Label | Parameter Name a |
Parameter Estimate (std. error) |
Covariate Estimate (standard error) |
−2 log likelihood (p-value e) |
||
|---|---|---|---|---|---|---|
| log(Size)b | GA Stratac | Creatinine Clearanced |
||||
| Base Model | Volume (V) | 0.5115 (0.0345) | 2708.2 (NA) | |||
| Clearance (Cl) | 0.0679 (0.0064) | |||||
| Endogenous Production (R) | 2.666 (0.2762) | |||||
| log(Size) | Volume (V) | 0.5177 (0.0359) | 2702.3 (0.02) | |||
| Clearance (Cl) | 0.0661 (0.0059) | 0.3544 (0.1460) | ||||
| Endogenous Production (R) | 2.542 (0.2566) | |||||
| GA Strata | Volume (V) | 0.5937 (0.0546) | −0.2776 (0.1286) | 2704.1 (0.04) | ||
| Clearance (Cl) | 0.0660 (0.0059) | |||||
| Endogenous Production (R) | 2.572 (0.2566) | |||||
| Creatinine Clearance | Volume (V) | 0.5096 (0.0341) | 2701.1 (0.03) | |||
| Clearance (Cl) | 0.0671 (0.065) | |||||
| Endogenous Production (R) | 3.273 (0.430) | −0.3252 (0.1260) | ||||
| All Covariates | Volume (V) | 0.5924 (0.0539) | −0.2777 (0.1257) | 2697.4 (0.03) | ||
| Clearance (Cl) | 0.0549 (0.0120) | 0.2158 (0.1963) | ||||
| Endogenous Production (R) | 3.040 (0.457) | −0.1898 (0.1583) | ||||
a
Units – V in L/kg, Cl in L/kg/h, R in mg/kg/h; where L: liters of serum, kg: kg’s of body weight, mg; mg’s of inositol, h: hours
b
log(Size): Natural logarithm of wi/w̃ where wi is the birth weight, in grams, for the i-th infant, w̃ is the median birth weight of the infants in the study (997.5 gm);
c
Gestational Age Strata: Reference cell 23–26 weeks; Comparison cell 27–29 weeks;
d
Creatinine Clearance: clearance in ml/min
e
p-value for testing the model including the covariates versus the base model without the covariates.