Effects of Secondhand Smoke Exposure on the Health and Development of African American Premature Infants

Table 2

Effects of secondhand smoke exposure and covariates from mixed model analyses for infant growth outcomes.

Variables	Estimate (SE)	DF	𝑡 value	pr>|𝑡|
Weight
Household smoker versus no smoker
Mean change from 6 to 12 months	−0.03 (0.19)	321	−0.14	0.8859
Mean change from 6 to 18 months	0.03 (0.26)	311	0.10	0.9199
Mean change from 6 to 24 months	0.16 (0.27)	211	0.59	0.5576
Maternal smoker versus not
Mean change from 6 to 12 months	0.05 (0.21)	318	0.24	0.8134
Mean change from 6 to 18 months	0.13 (0.29)	298	0.46	0.6426
Mean change from 6 to 24 months	0.25 (0.29)	191	0.85	0.3947
Height
Household smoker versus no smoker
Mean change from 6 to 12 months	0.67 (0.79)	310	0.85	0.3937
Mean change from 6 to 18 months	1.04 (1.04)	306	1.00	0.3166
Mean change from 6 to 24 months	1.12 (0.95)	205	1.18	0.2398
Maternal smoker versus not
Mean change from 6 to 12 months	0.80 (0.91)	308	0.88	0.3792
Mean change from 6 to 18 months	1.12 (1.21)	297	0.93	0.3552
Mean change from 6 to 24 months	0.96 (1.11)	193	0.86	0.3894
Head circumference
Household smoker versus no smoker
Mean change from 6 to 12 months	−1.18 (0.36)*	289	−3.31	0.0011
Mean change from 6 to 18 months	−1.58 (0.49)*	273	−3.24	0.0014
Mean change from 6 to 24 months	−1.20 (0.45)*	189	−2.63	0.0092
Maternal smoker versus not
Mean change from 6 to 12 months	−1.29 (0.44)*	289	−2.93	0.0036
Mean change from 6 to 18 months	−1.76 (0.61)*	269	−2.87	0.0044
Mean change from 6 to 24 months	−1.39 (0.58)*	193	−2.41	0.0171

*indicates that P values are significant at the  .05 level.