TABLE 4.
Unadjusted ORs and aORs From Logistic Regression Models for Each of the Criteria for the Mediation Analysis: Massachusetts Singleton Births, July 1, 2004, to December 31, 2008
| Criteria for mediation | Unadjusted ORa (95% CI) | P | aORb (95% CI) | P |
|---|---|---|---|---|
| ART versus Fertile (N = 312 790) | ||||
| 1. Relationship between ART and EI enrollment | 1.17 (1.10 – 1.25) | <.001 | 1.34 (1.26 – 1.44) | <.001 |
| 2. Relationship between ART and preterm | 1.70 (1.57 – 1.85) | <.001 | 1.45 (1.32 – 1.59) | <.001 |
| 3. Relationship between preterm and EI enrollment | 3.21 (3.11 – 3.31) | <.001 | 2.60 (2.51 – 2.68) | <.001 |
| Subfertile versus Fertile (N = 311 858) | ||||
| 1. Relationship between Subfertile and EI enrollment | 1.07 (1.00 – 1.15) | .06 | 1.21 (1.13 – 1.31) | <.001 |
| 2. Relationship between Subfertile and preterm | 1.28 (1.16 – 1.42) | <.001 | 1.18 (1.06 – 1.31) | .003 |
| 3. Relationship between preterm and EI enrollment | 3.18 (3.08 – 3.28) | <.001 | 2.57 (2.48 – 2.66) | <.001 |
a
For the first 2 assumptions, the unadjusted OR is the crude OR of the association. For the third assumption, the unadjusted OR is the association of EI enrollment (outcome) and preterm (mediator), controlling only for fertility status (exposure).
b
Models adjusted for maternal demographic characteristics (maternal age, race, education, marital status, nativity), insurance, smoking, prenatal care, parity, gender, labor and delivery complications, and abnormal conditions of the newborn.