Abstract
Being born preterm and being raised in poverty are each linked
with worse cognitive and academic outcomes. While socioeconomic
status (SES) has often been treated as a confounding factor in
studies of the developmental impacts of preterm birth, it has also
been hypothesized that SES acts as an effect modifier of the
relationship between preterm birth and cognitive and academic
outcomes. Since preterm children may be more vulnerable to the
adverse developmental impacts of growing up in disadvantaged
households, it is plausible that lower SES exacerbates the adverse
impacts of preterm birth. Conversely, it is also possible that
childhood poverty exerts such profound effects on cognitive
outcomes that being born early does not contribute additional
substantial risk. This dissertation investigated whether SES
modifies the effect of preterm birth on children's cognitive and
academic outcomes in early childhood through entry into school with
an explicit focus on assessment of additive interaction. Data
sources were the Early Childhood Longitudinal Study-Birth Cohort
(ECLS-B) and the Millennium Cohort Study (MCS). The ECLS-B and MCS
were longitudinal birth cohorts that enrolled 10,700 children in
the US and 18,818 children in the UK, respectively, in 2001 and
followed them through childhood with prospective measurement of
cognitive development. The first goal was to better understand
patterns of cognitive outcomes with each additional gestational
week (Aim 1). In ECLS-B, those born early preterm, moderate
preterm, or late preterm scored worse than term children on
cognitive ability tests at two years old and reading and
mathematics tests at kindergarten but there were no significant
differences observed for other gestational ages. The second goal
was to assess the presence of additive interaction between preterm
or early term birth and household SES in their effects on cognitive
scores in ECLS-B (Aim 2) and MCS (Aim 3). In ECLS-B, adjusted
deficits were 0.4-0.6 standard deviations (SD) for early preterm,
0.2-0.3 SD for moderate preterm, and 0.1 SD for late preterm
compared with term, and 0.6-0.9 SD comparing highest versus lowest
SES quintiles on cognitive ability tests at two years old and
reading and mathematics tests at kindergarten. In MCS, adjusted
deficits were 0.2-0.3 SD for early or moderate preterm, 0.1 SD for
late preterm, and 0.05 SD for early term compared with term, and
0.3-0.4 SD for children living in poverty compared with those not
living in poverty on cognitive assessments at three, five, and
seven years old. In both studies, there was no evidence of additive
interaction between the two risk factors; household SES did not
modify the relationship between gestational age and cognitive
outcomes. Findings underscore the important adverse impacts of both
being born preterm and being raised in more disadvantaged
households on children's cognitive outcomes. The estimated joint
effects were additive with doubly exposed children performing the
worst, suggesting the need for targeting of early childhood
interventions to these high-risk children.
Table of Contents
Chapter 1. Introduction
Chapter 2. Background
Chapter 3. Data Sources
Chapter 4. Describing the shape of the relationship between
gestational age at birth and cognitive development in a nationally
representative U.S. birth cohort
Chapter 5: Does socioeconomic status modify the association between
preterm birth and children's early cognitive ability and
kindergarten academic achievement in the United States?
Chapter 6: Preterm birth, childhood poverty, and cognitive
development among children in the United Kingdom
Chapter 7: Conclusions and Future Directions
Appendix
About this Dissertation
Rights statement
- Permission granted by the author to include this thesis or dissertation in this repository. All rights reserved by the author. Please contact the author for information regarding the reproduction and use of this thesis or dissertation.
School |
|
Department |
|
Degree |
|
Submission |
|
Language |
|
Research Field |
|
Keyword |
|
Committee Chair / Thesis Advisor |
|
Committee Members |
|