Three essays on Supplementary Health Insurance.

Summary This thesis is devoted to mixed health insurance systems where compulsory public coverage can be improved by a complementary health insurance. The questions addressed concern the inflationary effect of the complementary health insurance on the price of care and the impact of age-based pricing on solidarity between sick and healthy people and between income groups. The empirical analyses are based on French data. This original database includes the health care consumption of 99,878 MGEN members over the 2010-2012 period. Chapter 1 estimates the causal effect of better coverage on the consumption of excess fees and demonstrates the inflationary effect of complementary health insurance on the price of care. Chapter 2 considers the heterogeneity of the impact of better coverage on overcharges and its correlation with insurance demand. In fact, the inflationary effect of complementary insurance is accentuated by selection effects. Chapter 3 shows that age-based pricing maximizes transfers between the sick and the healthy at the expense of solidarity between high and low incomes.