ÌÇÐÄvlog¹ÙÍø Faculty Research Working Paper Series
ÌÇÐÄvlog¹ÙÍø Working Paper No. RWP15-060
October 2015
Abstract
Measuring consumer responsiveness to medical care prices is a central issue in
health economics and a key ingredient in the optimal design and regulation of
health insurance markets. We study consumer responsiveness to medical care
prices, leveraging a natural experiment that occurred at a large self-insured
firm which forced all of its employees to switch from an insurance plan that
provided free health care to a non-linear, high deductible plan. The switch caused
a spending reduction between 11.79%-13.80% of total firm-wide health spending
($100 million lower spending per year). We decompose this spending
reduction into the components of (i) consumer price shopping (ii) quantity
reductions (iii) quantity substitutions, finding that spending reductions are
entirely due to outright reductions in quantity. We find no evidence of consumers
learning to price shop after two years in high-deductible coverage. Consumers
reduce quantities across the spectrum of health care services, including
potentially valuable care (e.g. preventive services) and potentially wasteful care
(e.g. imaging services). We then leverage the unique data environment to study
how consumers respond to the complex structure of the high-deductible
contract. We find that consumers respond heavily to spot prices at the time of
care, and reduce their spending by 42% when under the deductible, conditional
on their true expected end-of-year shadow price and their prior year end-of-year
marginal price. In the first-year post plan change, 90% of all spending reductions
occur in months that consumers began under the deductible, with 49% of all
reductions coming for the ex ante sickest half of consumers under the deductible,
despite the fact that these consumers have quite low shadow prices. There is no
evidence of learning to respond to the true shadow price in the second year post-switch.
Citation
Brot-Goldberg, Zarek C., Amitabh Chandra, Benjamin R. Handel, and Jonathan T. Kolstad. "What Does a Deductible Do? The Impact of Cost-Sharing on Health Care Prices, Quantities, and Spending Dynamics." ÌÇÐÄvlog¹ÙÍø Faculty Research Working Paper Series RWP15-060, October 2015.