Table 3.

Odds of Breastfeeding Initiation and Duration Using Full and Reduced Variables Models in Six and Five Sites in Pre-schoolers With Autism Spectrum Disorder Versus Controls Enrolled in the Study to Explore Early Development

	Full variables modela		Reduced variables model
Breastfeeding parameter	Unadjusted odds-ratios and 95% confidence interval	Adjusted odds-ratios and 95% confidence interval	Unadjusted odds-ratios and 95% confidence interval	Adjusted odds-ratios and 95% confidence interval
Breastfeeding initiation in six sitesb	0.62 (0.45, 0.85)	0.88 (0.60,1.28)	0.62 (0.45, 0.85)	0.89 (0.61, 1.28)b
Breastfeeding initiation in five sitesc	0.61 (0.44, 0.85)	0.87 (0.58, 1.30)	0.61 (0.44, 0.85)	0.90 (0.61, 1.33)c
Breastfeeding duration in six sites (high tertile vs. low tertile)d	0.47 (0.36, 0.61)	0.61 (0.45, 0.84)	0.47 (0.36, 0.61)	0.61 (0.44, 0.83)d
Breastfeeding duration in five sites (high tertile vs. low tertile)e	0.46 (0.35, 0.62)	0.60 (0.42, 0.85)	0.46 (0.35, 0.62)	0.60 (0.42, 0.84)e
Breastfeeding duration in six sites (middle tertile vs. low tertile)d	0.55 (0.42, 0.71)	0.72 (0.54, 0.98)	0.55 (0.42, 0.71)	0.73 (0.54, 0.98)d
Breastfeeding duration in five sites (middle tertile vs. low tertile)e	0.50 (0.38, 0.66)	0.64 (0.46, 0.89)	0.50 (0.38, 0.66)	0.64 (0.46, 0.88)e

Note. Bold values are assessed at the P-value of <0.05.

^aAdjusted for the following variables: child sex, gestational age, birth weight, 5-min Apgar score, birth plurality, mode of delivery; mother’s age at the time of child’s birth in years, parity with the index child, race and ethnicity, education at time of child’s birth, place of birth, employment status during the 3 months before the child’s birth until the end of breastfeeding period, marital status, smoking status, and presence of neuropsychiatric diagnoses; family estimated income during the year preceding the index child’s birth, and study site.

^bAdjusted in the reduced variables model for maternal age, race, education, place of birth, family income, maternal psychiatric diagnoses, child sex, gestational age, mode of delivery.

^cAdjusted in the reduced variables model for all the variables in six site reduced variables model listed above plus mother’s marital status.

^dAdjusted in the reduced variables model for maternal age, race, ethnicity, education, family income, maternal psychiatric diagnoses, child sex, gestational age, birth weight, birth plurality, mode of delivery.

^eAdjusted in the reduced variables model for all the variables in six site reduced variables model listed above plus mother’s marital status.