خود انتخابی و خطر اخلاقی در بیمه سلامت شیلی

We study the existence of self-selection and moral hazard in the Chilean health insurance industry. Dependent workers must purchase health insurance either from one public or several private insurance providers. For them, we analyze the relationship between health care services utilization and the choice of either private or public insurance. In the case of independent workers, where there is no mandate, we analyze the relationship between utilization and the decision to voluntarily purchase health insurance. The results show self-selection against insurance companies for independent workers, and against public insurance for dependent workers. Moral hazard is negligible in the case of hospitalization, but for medical visits, it is quantitatively important.

We study the interaction between the purchase (and design) of health insurance and health care service utilization in the Chilean health system. The relationship arises from the effect of the purchase/design of insurance policies on utilization through moral hazard and consumer self-selection. Significant effects of insurance on the demand for health services (moral hazard) have been found in the literature (see Newhouse (1993) for the US; Cameron et al. (1988) for Australia; and Bertranou (1998) for Argentina).1 Regardingadverse selection, Cutler and Zeckhauser (1998), Cutler and Reber (1998), Cameron et al. (1988), and Bertranou (1998), find significant adverse selection among consumers of the various health insurance plans they analyze. Our study of the behavior of independent workers, with and without insurance, replicates what is traditionally done in the literature. The usual finding is that those who voluntarily purchase health insurance have a higher health risk than an average individual in the population, and consume more health care services than if they were not insured. Dependent workers2 must spend 7% of their taxable income on health insurance, and must choose between purchasing public insurance (from the National Health Fund or Fondo Nacional de Salud (FONASA)); or private insurance (from one of several Instituciones de Salud Previsional (ISAPREs)).3 Among this group of workers, we look for self-selection and over-utilization associated with the purchase of one kind of insurance, as opposed to the other. To measure self-selection, we analyze the relation between the probability of affiliation to one kind of insurance, and the observable and non-observable characteristics of the beneficiaries. To estimate over-utilization, we compare the utilization of health care services with public and private insurance. Two characteristics of the Chilean health insurance system allow us to presume the existence of self-selection. In both cases, self-selection is expected to operate against public insurance. The first consists of the difference in premiums in public and private insurance policies (see Aedo and Sapelli, 1999). Public insurance sets its premiums as a percentage of income, while private insurance uses risk rating. Private insurance institutions are allowed, by law, to adjust premiums according to age, sex, and number of dependents. Thus, public insurance is relatively more attractive for those with higher risk factors, since the effective price of public insurance is lower. Thus, those who purchase public insurance, on average, are expected to exhibit higher observable risk than those who purchase private insurance. The second characteristic that leads to self-selection against public insurance is the free implicit insurance offered by public insurance. First, until recently, public insurance was not able to determine whether or not a patient was affiliated to a private insurance health plan. This provided an incentive for private insurance beneficiaries to make (unauthorized) sequential use of both types of insurance, according to their relative price and quality. Second, private insurance beneficiaries are permitted to switch back to public insurance; thus, public insurance operates explicitly as a last-resort insurer.4 This implies that public insurance beneficiaries, on average, should exhibit greater non-observable risk than private insurance beneficiaries.

For independent workers, we find that insurance plans in Chile receive an adverse selection of the population, and their affiliates consume more than they would have if they had not purchased insurance (moral hazard). When analyzing the choice between public insurance and private insurance for dependent workers, we find that self-selection is present against public insurance based on variableswhich are observable (by private insurance and researchers). This is to be expected, given the different pricing structure of each type of insurance: private insurance has risk-adjusted premiums, while public insurance does not. With respect to non-observable variables, we find that self-selection is only present in hospitalization, and operates against public insurance. This result may be related to public insurance providing free catastrophic insurance. Private insurance does not face adverse selection, possibly due to the design of insurance plans. However, this design does not prevent over-utilization. To measure over-utilization, we examine whether people consume more after choosing private insurance (or public insurance), than theywould have had they preferred the other insurance. The results indicate that, for physician visits, over-utilization is present in both public and private insurance. This result implies that individuals allocate themselves according to where they have an utilization “comparative advantage”; individuals choose the type of insurance which allows them to consume the most. This allocation is possible due to the different pricing structures in public and private insurance. There is no over-utilization in the case of hospitalization, for either public insurance or private insurance. This is to be expected, since the price elasticity of demand for hospitalization is low. In sum, for independent workers, our findings replicate those usually found in the literature. For dependent workers, we find that the existence of a mixed system may increase moral hazard in comparison to a system where there is only one type of insurance. Since insured persons select the type of insurance which permits them to consume the most (public or private insurance), the design of the system may be increasing the magnitude of the moral hazard problem.