The distortionary effect of health insurance on health demand

Abstract

This paper presents a general framework for modeling the impact of insurance on healthcare demand extending some of the results of the two-risk model of Rothschild and Stiglitz (1976), but including the latter as a special case. Rothschild and Stiglitz's approach assumes equivalence between the price of treatment and the discomfort caused by the disease. Relaxing this assumption turns out to be key in understanding participation in the insurance and healthcare markets. The demands for insurance and healthcare are modeled simultaneously, under symmetric and asymmetric information. Four main results arise from the relaxation of this assumption. First, only the presence of an insurance market can produce healthcare consumption at higher prices than the discomfort. Second, adverse selection may lead healthcare to be sold at a price lower than that under perfect information. Third, the potential non-participation of one type risk arises despite competition, depending on the degree of information. Last, in a public voluntary regime, one type risk may prefer to be uninsured and still consume healthcare.health insurance ; adverse selection ; health care, public/private ; compulsory/voluntary insurance