Why more cost-sharing won't slow Medicare spending.

In considering ways to slow the growth in Medicare expenditures, policymakers have concluded that increasing point-of-service cost-sharing for patients will reduce demand for health services. Under the current system, Medicare beneficiaries faced with increased cost-sharing can reduce their demand for services or purchase additional private insurance. New data from the 1991 Medicare Current Beneficiary Survey show that high-income persons protect themselves from out-of-pocket costs by purchasing private supplemental insurance. Surprisingly, the data also reveal that many low-income persons also purchase private insurance, demonstrating that the elderly--whatever their income level--consider supplementary insurance more of a necessity than a luxury. Thus, it appears that increased beneficiary cost-sharing would have a limited effect on Medicare spending growth.