. Author manuscript; available in PMC: 2018 May 1.

Published in final edited form as: Prev Sci. 2017 May;18(4):416–427. doi: 10.1007/s11121-017-0780-6

Table 4a.

Covariate ^a effects on Maternal Smoking and Drinking Trajectories (N=8,800), ECLS-B (Reference class: NS-ND)

	Drinking Classes		Concurrent Users

			Predominantly Smokers		Both Alc/Cigs

	NS-MPD (25.8%)	NS-EHPD (8.4%)	TRS-LPD (10.7%)	HS-DPD (8.6%)	TRS-HPD (5.9%)

	AOR^b	AOR	AOR	AOR	AOR
Maternal Age
Age 18–25	–	0.17^**	2.04^**	–	–
Age 36+	–	2.21^**	–	–	–
Maternal Race/Ethnicity
Black	0.45^**	0.19^**	0.27^**	0.03^**	0.40^**
Hispanic	0.37^**	0.26^**	0.23^**	0.02^**	0.14^**
Asian and Others	0.42^**	0.21^**	0.41^**	0.28^**	0.49^**
Mother Married or Cohabiting with Partner
Yes	0.58^**	–	0.72^*	0.65^*	0.46^**
Maternal Education
High school	1.56^*	–	–	0.55^**	1.88^*
Some college	2.18^**	–	0.60^*	0.29^**	–
College or grad school	2.48^**	5.40^*	0.16^**	0.04^**	–
Household Income (proportion of federal poverty line)
100–130%	–	–	–	–	–
130–185%	–	–	–	–	–
>185%	2.43^**	6.92^*	–	0.63^*	2.25^**
Moderate or Severe Postpartum Depression
Depressed	–	–	1.45^**	2.21^*	–
Breastfeeding
≤ 6 months	1.37^*	1.76^*	–	0.76^*	–
> 6 months	–	–	0.32^**	0.22^**	0.40^**
Maternal Employment Status
Part-time	1.55^**	1.69^**	1.35^*	–	1.76^**
Full-time	1.51^**	–	–	1.40^*	–
Planned pregnancy	–	–	0.73^*	0.65^**	0.69^*

P-value <0.05

^**

P-value<0.01

The choice of reference category for each covariates were carefully selected based on theory, empirical distribution, as well as past literature. The reference category for Maternal Age is 26–35, for Maternal Race/Ethnicity is White, for Maternal Education is Less than high school, for Household Income is Lower than poverty line, for Breastfeeding is Never breastfeed, and for Employment Status is Not employed.

Adjusted Odds Ratio; AOR greater than 1 represents increasing log odds of being assigned to a given class compared to the NS-ND class.