I am an assistant professor in the Graduate School of Economics at the University of Osaka in Japan.
My research interests center on health economics, with a particular focus on the health and well-being of families and children.
contact: chien-tzu_cheng(at)econ.osaka-u.ac.jp
See You at Night: Unintended Consequences of Raising Provider Payments for Nighttime Emergency Care
with Hsien-Ming Lien [Draft]
Using administrative data from Taiwan's single-payer healthcare system, this paper studies a 2010 reform that raised the diagnostic fee for nighttime emergency department (ED) visits by 25 percent. We exploit the payment discontinuity in a regression discontinuity in time design, adopting an augmented local linear approach. We find no effects on care provision, treatment intensity, or visit volume, and no substitution between emergency and primary care. What changes instead is the composition of nighttime visits: the share of low-acuity visits rises by 37 percent, with no corresponding change among high-severity cases. The pattern is consistent with hospitals delaying the registration of wait-tolerant patients until just after the payment cutoff: a purely temporal reallocation that raises reimbursement without altering the treatment delivered, the diagnosis recorded, or the patients seen. Downstream health outcomes are unaffected. Where a fee is paid to the organization rather than the practitioner, targeted subsidies may purchase administrative adjustment rather than the capacity they were designed to expand.
When More Prenatal Care Looks Like Less: Selection, Information and Maternal and Infant Health
with Shin-Yi Chou, Hsien-Ming Lien [Draft available upon request.]
We use Taiwan's 2003 SARS epidemic as a natural experiment, instrumenting prenatal care with gestational exposure to SARS-induced fear that reduced visits by over 20 percent. Adequate prenatal care reduces preventable maternal complications by 3.4 percentage points (26 percent), with no effect on infant outcomes. OLS estimates are perversely signed for maternal complications but overstate benefits for infant outcomes, consistent with competing patient- and provider-driven selection. Mechanism evidence points to prenatal care as a longitudinal information system: repeated contact facilitates detection of evolving risks and generates clinical information that informs delivery decisions, including delivery-mode routing and subsequent management at delivery.
The Impact of Home Pregnancy Testing on Fertility and Women's Later-Life Outcomes
[Draft available upon request.]
Home pregnancy tests give early fertility information and help women make timely family-planning decisions. This paper studies how the introduction of home pregnancy tests in the US in 1977 impacted fertility, early prenatal care, and later-life outcomes. Using county-level drugstore accessibility to approximate test availability, I document significant trend breaks in fertility rates after 1977 among women who had access to drugstores. The effects are the strongest for those aged 15–29 and concentrated among those with access to abortion services. In the long run, women exposed to home pregnancy tests were more likely to delay childbirth, participate in the labor force, and never marry; these women were also less likely to divorce.