“Breast is Best, But for How Long? Testing Breastfeeding Guidelines for Optimal Cognitive Ability

Objectives. To investigate the relationship between breastfeeding duration and cognitive development using longitudinal survey data. The World Health Organisation (WHO) and the American Academy of Pediatrics (AAP) recommend exclusive breastfeeding until six months post-partum and a combination of complementary foods and breast milk thereafter. This study estimates non-parametric regression models to test whether these recommendations also hold for cognitive ability. Design. Longitudinal cohort study with two waves of 18,819 children who were born in the UK between 2000-2002. We estimate several generalised additive regression models to examine the impact of exclusive and non-exclusive breastfeeding duration on cognitive ability, while controlling for a range of confounding family characteristics. Setting and Participants: Participants of the UK Millennium Cohort Study (MCS). Main outcome measures: Cognitive development at age three as measured by the Bracken School Readiness Assessment. Results. The models identify a non-linear relationship between exclusive and non-exclusive breastfeeding and cognitive ability. There are high initial positive returns to exclusive breastfeeding which peak at six months, with the returns to non-exclusive breastfeeding continuing to increase until 10/12 months. These results suggest that the WHO/AAP guidelines recommending exclusive breastfeeding for the first 6 months of life also hold for optimal cognitive ability. The models also show that the optimal switching point from exclusive to nonexclusive breastfeeding occurs at six months, and that a combination of breast milk and solids should continue until thereafter, peaking at 10 months. Conclusion. While breastfeeding recommendations primarily target physical growth and development, our study confirms that such recommendations are also optimal for cognitive development. These results provide further evidence that recent UK policy initiatives to extend paid maternity leave is appropriate for the maximal development of the child’s cognitive ability. While this study controls for a range of confounding factors, there may still exist unobserved family characteristics which mediate this relationship.

Three essays in health economics : determinants of individual health, medical care use, and treatment

This dissertation studies and identifies determinants of individual health. The first chapter analyzes how the supply of medical care affects patient treatment and health outcomes, focusing on how hospitals respond to the loss of a profitable service line. This chapter provides strong evidence that hospital spillovers across service lines are empirically important and that hospitals differentiate treatment by patient payer type. Hospitals practice both revenue augmenting and cost-cutting behavior in other lines of care, targeting specific procedures and payers according to their profitability. Specifically, they increase the number of surgical procedures and perform more marginal surgeries. The effects are concentrated in medical specialties where there are more discretionary surgeries and higher profit margins. Furthermore, hospitals cut back on unprofitable treatment by reducing non-elective admissions and uninsured elective care. Hospitals also increase the intensity of treatment among private payers. The second chapter of this dissertation investigates the demand side of health care, analyzing the role that health insurance plays on primary medical care usage by young American adults. I find office-based physician visits and prescription drugs are not affected by insurance, but dental visits are. There is a small increase in out-of-pocket expenditures caused by insurance loss, concentrated heavily at the top of the distribution. No change in health status or ability to afford care is found. The findings shed light on the expected welfare benefits of recent US health care policies targeting young adults. The final chapter of this dissertation analyzes the extent to which the early childhood environment shapes child health and development outcomes and, specifically, whether universal childcare levels the playing field across children. I analyze the introduction of a universal childcare program in Quebec in 1997, testing its impact on the distribution of child health and development outcomes. I find that there is little heterogeneity in the response to the policy across the distributions of child motor skills and cognitive outcomes. I do, however, find evidence that it led to a reduction in child body weight at the upper end of the distribution.Arts, Faculty ofVancouver School of EconomicsGraduat

Breast is best, but for how long? Testing breastfeeding guidelines for optimal cognitive ability

Objectives: To investigate the relationship between breastfeeding duration and cognitive development using longitudinal survey data. The World Health Organisation (WHO) and the American Academy of Pediatrics (AAP) recommend exclusive breastfeeding until six months post-partum and a combination of complementary foods and breast milk thereafter. This study estimates non-parametric regression models to test whether these recommendations also hold for cognitive ability. Design: Longitudinal cohort study with two waves of 18,819 children who were born in the UK between 2000-2002. We estimate several generalised additive regression models to examine the impact of exclusive and non-exclusive breastfeeding duration on cognitive ability, while controlling for a range of confounding family characteristics. Setting and Participants: Participants of the UK Millennium Cohort Study (MCS). Main outcome measures: Cognitive development at age three as measured by the Bracken School Readiness Assessment. Results: The models identify a non-linear relationship between exclusive and non-exclusive breastfeeding and cognitive ability. There are high initial positive returns to exclusive breastfeeding which peak at six months, with the returns to non-exclusive breastfeeding continuing to increase until 10/12 months. These results suggest that the WHO/AAP guidelines recommending exclusive breastfeeding for the first 6 months of life also hold for optimal cognitive ability. The models also show that the optimal switching point from exclusive to nonexclusive breastfeeding occurs at six months, and that a combination of breast milk and solids should continue until thereafter, peaking at 10 months. Conclusion: While breastfeeding recommendations primarily target physical growth and development, our study confirms that such recommendations are also optimal for cognitive development. These results provide further evidence that recent UK policy initiatives to extend paid maternity leave is appropriate for the maximal development of the child’s cognitive ability. While this study controls for a range of confounding factors, there may still exist unobserved family characteristics which mediate this relationship