本文針對全民健康保險制度之保險費率與給付比率的變動對消費分配的影響，進 行較為嚴謹的理論探討與分析。一般認為，健康保險具有使消費分配均等化的功能，惟在本 文諸多的簡化假設下，上述兩項措施的重分配效果猶有不明確之處。可以確定的是，在完全 競爭且供給完全彈性的醫療服務市場裡，提高保險費率，在降低全社會的平均消費水準之同 時，亦促使全社會的消費不均程度改善。而調高給付比率，假若消費者的相對風險規避指標 值小於或等於一，則全社會的平均消費水準亦造下降。至於調高給付比率之後，消費分配是 改善抑或加重不均程度，皆有可能。因此，假若基於維持保險財務平衡的考量而同時調高保 險費率與給付比率，則全社會的平均消費必定下降，消費分配的不均程度則未必改善。
This paper provides a theoretical analysis of the effects of national health insurance on consumption distribution, especially with regard to changes in premiums and coinsurance. In general, health insurance is expected to have an advantageous influence on consumption equity. However, under the simplifying assumptions imposed in the paper, we show that the redistribution consequences of these two measures are not always unambiguous. The conclusion we reach is that, in a perfectly competitive medical care market with constant marginal cost, an increase in premium rates will reduce the average societal consumption on the one hand and lessen consumption inequality on the other hand. However, lowering the rate of coinsurance may lead to higher inequality of consumption, while it still cuts down the consumption level in cases where the Arrow-Pratt measure of relative risk aversion is not greater than one.
