The mandatory health insurance system in Chile: explaining the choice between public and private insurance.

In Chile, dependent workers and retirees are mandated by law to purchase health insurance, and can choose between private and public health insurance. This paper studies the determinants of the choice of health insurance. Earnings are generally considered the key factor in this choice, and we confirm this, but find that other factors are also important. It is particularly interesting to analyze how the individual's characteristics interact with the design of the system to influence choice. Worse health, as signaled by age or sex (e.g., older people or women in reproductive ages), results in adverse selection against the public health insurance system. This is due to the lack of risk adjustment of the public health insurance's premium. Hence, Chile's risk selection problem is, at least in part, due to the design of the Chilean public insurance system.