Table 6.

Estimates with interaction of caffeine and duration of treatment

Effect	Estimate (logit)	Standard Error	P
Intercept	3.39	5.99	0.57
Average Caffeine dose (mg/kg/d)	0.24	0.09	0.029*
Duration of caffeine treatment (days)	0.64	0.27	0.02*
Caffeine dose* Duration of caffeine treatment (days)	0.07	0.04	0.05*
Steroid cumulative dose (mg)	0.09	0.05	0.07
Vitamin D (units)	−1.86	0.36	0.04*
Average biweekly Birth Weight (grams)	−0.06	0.02	0.001*
Gestational age (weeks)	−0.64	0.15	0.001*

p* Indicates significant level