Table 2 Logistic Regression Model Estimating Preterm Rates among Women Enrolled in Medicaid

Independent Variable

95% C.I.

95% C.I.

95% C.I.

95% C.I.

 Age

1.00

1.00–1.00e

1.00

1.00–1.00e

1.00

1.00–1.00e

1.00

0.99–1.01

  (Reference: White)

–

–

–

–

–

–

–

–

 Black

1.35

**

1.32–1.38

–

–

–

–

–

–

 Hispanic

0.83

**

0.79–0.87

–

–

–

–

–

–

 Other

0.99

0.95–1.02

–

–

–

–

–

–

 Smoking

1.50

**

1.3–1.73

1.64

**

1.38–1.94

1.07

0.77–1.48

2.03

0.45–9.11

 Drug Dependence

2.21

**

2.02–2.42

2.12

**

1.91–2.34

2.56

**

1.92–3.41

1.42

0.42–4.78

 Alcohol Dependence

2.09

**

1.71–2.55

2.11

**

1.58–2.8

2.03

**

1.47–2.81

1.45

0.34–6.29

 Diabetes

1.27

**

1.23–1.32

1.27

**

1.2–1.34

1.25

**

1.17–1.33

1.44

**

1.27–1.64

 Hypertension

1.82

**

1.77–1.87

1.77

**

1.7–1.85

1.83

**

1.76–1.91

1.98

**

1.74–2.26

  (Reference: No High Risk Prenatal Encounter)

–

–

–

–

–

–

–

–

 1+ High Risk Prenatal Encounter

1.39

**

1.35–1.42

1.45

**

1.4–1.5

1.28

**

1.24–1.33

1.55

**

1.38–1.74

  (Reference: 8+ Prenatal Visits)

–

–

–

–

–

–

–

–

 No Prenatal Visits

1.78

**

1.72–1.84

1.63

**

1.55–1.72

2.04

**

1.92–2.17

1.58

**

1.34–1.87

 Between 1 and 7 Prenatal Visits

1.68

**

1.64–1.73

1.58

**

1.52–1.64

1.83

**

1.75–1.91

1.47

**

1.24–1.74

Constant

0.04

**

0.04–0.04

0.04

**

0.04–0.05

0.05

**

0.05–0.06

0.04

**

0.03–0.05

Number of Observations

457,144

231,912

141,374

30,902

Model Chi-Square Test

6258.3

**

(12 df)

2338.4

**

(9 df)

2154.6

**

(9 df)

233.6

**

(9 df)

* p < .01; **p < .001.