Table 5.

Linear regression analysis of risk factors (regression model values: R square=0.153; adjusted R square=0.149, standard error=6.393; F=42.443; p=0.000)

Predictor	B	Standard error	Beta	t	Significance (p value)
Age	−0.047	0.028	−0.039	−1.707	0.088
Week of pregnancy	−0.074	0.021	−0.063	−3.588	<0.001
Years of education	−0.168	0.059	−0.069	−2.830	0.005
Income	−0.405	0.073	−0.143	−5.561	<0.001
Number of children living in home	0.023	0.128	0.003	0.179	0.858
MHCa	0.054	0.009	0.115	5.820	<0.001
Married or living with partnera	−1.704	0.341	−0.099	−4.991	<0.001
Caucasiana	−0.428	0.329	−0.023	−1.299	0.194
Employeda	−0.912	0.267	−0.065	−3.412	0.001
Number of premature births <36 weeks	0.361	0.258	0.025	1.395	0.163
Number of stillbirths	1.800	0.580	0.054	3.104	0.002
Number of miscarriages	0.283	0.117	0.043	2.415	0.016

B unstandardized regression coefficients, beta standardized regression coefficients

^aCategorical variables were re-coded for linear regression