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Table 4 Breastfeeding duration estimated using a negative binomial model

From: Seasonal differences in breastfeeding in the United States: a secondary analysis of longitudinal survey data

 

All

Male

Female

Intercept

4.9966 (7.3766)

−0.3997 (10.2272)

10.5373 (10.6594)

Sex

 Male

−0.1215 (0.9719)

  

Season of birth

 Summer

1.5145 (1.3689)

−1.5044 (1.9895)

4.0767** (1.8889)

 Fall

1.9723 (1.3865)

0.1215 (2.0043)

3.7705** (1.9278)

 Winter

1.9264 (1.3812)

0.4624 (1.9652)

3.1146 (1.9554)

Race/ethnicity

 Black

−3.1933** (1.5553)

−3.4831 (2.2455)

−2.9703 (2.1645)

 Hispanic

−1.3716 (1.3344)

−0.1747 (1.9087)

−2.2999 (1.8707)

Education level

 High school

1.5619 (2.3159)

1.1650 (3.4197)

1.5911 (3.1691)

 Associate

2.8234 (2.6308)

1.2178 (3.8532)

4.2818 (3.6313)

 College

3.1363 (2.6817)

3.2755 (3.9200)

2.9931 (3.6988)

 Graduate school

6.5491** (2.9011)

6.0407 (4.2056)

6.6130 (4.0439)

 Other Degree

2.3204 (2.8535)

3.9257 (4.0243)

−0.2220 (4.1275)

Test score

 ASVAB math

0.0011*** (0.0002)

0.0009*** (0.0003)

0.0013*** (0.0003)

Mother’s lifestyle factors at the birth of the child

 Hours worked for pay

−0.0030*** (0.0006)

−0.0032*** (0.0008)

− 0.0027*** (0.0008)

 Income

0.0000 (0.0000)

0.0000 (0.0000)

0.0000 (0.0000)

 Married at birth

0.5815 (1.5629)

−1.2461 (2.2463)

2.5388 (2.1818)

 Age of mother at first birth

0.4950*** (0.1598)

0.7094*** (0.2270)

0.2952 (0.2259)

Age of mother at birth

 10–19

−5.9093** (3.0554)

−5.5479 (4.4112)

−5.3483 (4.2386)

 20–29

−2.6985 (1.7040)

−2.6266 (2.4916)

−2.4915 (2.3387)

Birth order of the child

 Firstborn

1.1044 (1.5698)

2.7261 (2.2892)

−0.7012 (2.1731)

 Youngest

3.7197** (1.5473)

4.0268 (2.2004)

3.1348 (2.1969)

Projected number of children

 Ideal family size desired as a teen

−0.0591 (0.3337)

−0.1663 (0.4669)

0.1015 (0.4774)

Number of kids ever born

 Two children

3.6467 (2.3488)

8.0871** (3.4305)

−0.7376 (3.2356)

 Three children

9.3003*** (2.7184)

14.3225*** (3.9210)

4.1879 (3.8208)

 Four children

9.1642*** (3.0622)

13.3359*** (4.4094)

4.7484 (4.2944)

 5+ children

12.8655*** (3.4816)

18.8453*** (5.0290)

7.1256 (4.8664)

Decade of child’s birth

 Seventies

−3.9606 (4.4815)

−4.0233 (6.5379)

−5.0121 (6.2320)

 Eighties

−7.7156** (3.2527)

−7.7721 (4.5957)

−8.3248 (4.6169)

 Nineties

−6.4642** (2.8224)

−7.0396 (3.9512)

−6.2624 (4.0305)

Scale

21.7123 (0.3402)

21.6101 (0.4771)

21.6193 (0.4808)

  1. ***Denotes significantly different from 0 at the 99% level, and ** at the 95% level