<p>This thesis focuses on two important areas of health economics: health dynamics during pre-adulthood, and physician behaviour. The first two essays seek to explore the important factors that determine the health production process during the period of pre-adulthood. The third chapter then turns the focus to physician labour and service provision behaviours.</p> <p>The first chapter examines the impact of family social economic status (SES) and neighbourhood environment on the dynamics of child <em>physical</em> health development. It examines the distribution of health outcomes and health transitions and explores the determinants of these distributions by estimating the contributions of family SES, neighbourhood status, unobserved heterogeneity and pure state dependence.</p> <p>The second chapter extends the research on health development in pre-adulthood by examining the roles of family SES, early childhood life-events, unobserved heterogeneity and pure state dependence in explaining the distribution of depression among adolescents and young adults. It also explicitly models the depression dynamics and quantifies both the mobility and persistence of this type of <em>mental</em> health problem from adolescence to early adulthood.</p> <p>The third chapter examines whether and how pay-for-performance (P4P) payments can motivate physician service provision to improve the quality of health care. It exploits a natural experiment in the province of Ontario, Canada to identify empirically the impact of P4P incentives on the provision of targeted primary care services, and whether physicians’ responses differ by age, practice size and baseline compliance level.</p> / Doctor of Philosophy (PhD)