Toshiaki Iizuka

Graduate School of Economics
University of Tokyo
Bunkyo-ku, Japan

E-Mail: EmailAddress: hidden: you can email any NBER-related person as first underscore last at nber dot org
Institutional Affiliation: University of Tokyo

NBER Working Papers and Publications

June 2019Are Quality-Adjusted Medical Prices Declining for Chronic Disease? Evidence from Diabetes Care in Four Health Systems
with Karen Eggleston, Brian K. Chen, Chih-Hung Chen, Ying Isabel Chen, Talitha Feenstra, Janet Tinkei Lam, Gabriel M. Leung, Jui-fen Rachel Lu, Beatriz Rodriguez-Sanchez, Jeroen N. Struijs, Jianchao Quan, Joseph P. Newhouse: w25971
Improvements in medical treatment have contributed to rising health spending. Yet there is relatively little evidence on whether the spending increase is “worth it” in the sense of producing better health outcomes of commensurate value—a critical question for understanding productivity in the health sector and, as that sector grows, for deriving an accurate quality-adjusted price index for an entire economy. We analyze individual-level panel data on medical spending and health outcomes for 123,548 patients with type 2 diabetes in four health systems. Using a “cost-of-living” method that measures value based on improved survival, we find a positive net value of diabetes care: the value of improved survival outweighs the added costs of care in each of the four health systems. This finding is...

Published: Karen Eggleston & Brian K. Chen & Chih-Hung Chen & Ying Isabel Chen & Talitha Feenstra & Toshiaki Iizuka & Janet Tin Kei Lam & Gabriel M. Leung & Jui-fen Rachel Lu & Beatriz Rodriguez-Sanchez & Jeroen N. Struijs & Jianchao Quan & Joseph P. Newhouse, 2020. "Are quality-adjusted medical prices declining for chronic disease? Evidence from diabetes care in four health systems," The European Journal of Health Economics, vol 21(5), pages 689-702.

November 2018Free for Children? Patient Cost-sharing and Healthcare Utilization
with Hitoshi Shigeoka: w25306
This study exploits over 5,000 variations in subsidy generosity across ages and municipalities in Japan to examine how children respond to healthcare prices. We find that free care significantly increases outpatient spending, with price elasticities considerably smaller than for adults. Price responses are substantially larger when small copayments are introduced, indicating more elastic demand around a zero price. We also find that increased utilization primarily reflects low-value and costly care: increased outpatient spending neither reduces subsequent hospitalization by “avoidable” conditions nor improves short- or medium-term health outcomes. By contrast, inappropriate use of antibiotics and costly after-hours visits increase.
May 2017Is Preventive Care Worth the Cost? Evidence from Mandatory Checkups in Japan
with Katsuhiko Nishiyama, Brian Chen, Karen Eggleston: w23413
Using unique individual-level panel data, we investigate whether preventive medical care triggered by health checkups is worth the cost. We exploit the fact that biomarkers just below and above a threshold may be viewed as random. We find that people respond to health signals and increase physician visits. However, we find no evidence that additional care is cost effective. For the “borderline type” (“pre-diabetes”) threshold for diabetes, medical care utilization increases but neither physical measures nor predicted risks of mortality or serious complications improve. For efficient use of medical resources, cost effectiveness of preventive care must be carefully examined.
November 2005Drug Advertising and Health Habit
with Ginger Zhe Jin: w11770
We examine the effect of direct-to-consumer advertising (DTCA) of drug treatment on an important health habit, physical exercise. By learning the existence of a new drug treatment via DTCA, rational consumers may become careless about maintaining healthy lifestyles. Using the National Health Insurance Survey (NHIS) and MSA-level DTCA data, we find that the DTCA related to four chronic conditions -- diabetes, high cholesterol, over weight, and hypertension -- reduce the likelihood of engaging in moderate exercise. This suggests the possibility that DTCA does not only affect pharmaceutical demand in the short-run, but also have long-run impacts on people's health by affecting their daily routines.
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