Chien-Tzu Cheng

I am an assistant professor in the Graduate School of Economics at Osaka University in Japan. 

My research interests focus on Health Economics and Labor Economics. 

Working Papers

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.

See You at Night: Unintended Consequences of Raising Physician Diagnostic Fees for Emergency Care

with Hsien-Ming Lien [Draft available upon request.]

Taiwan’s universal healthcare system compensates physicians' expertise through diagnostic fees while their wages remain market-determined. To assess the impact of diagnostic fees on medical inputs and outcomes, we examine a 2010 policy that increased nighttime emergency department (ED) diagnostic fees by approximately 30%. Using a regression discontinuity in time (RDiT), we find an immediate 7.6–8.3 percentage point (about 30%) increase in the share of nighttime admissions for the least urgent cases. Recognizing that institutional responses may take time, we also employ a parametric event-study approach to evaluate the impact of health outcomes after one year of policy implementation and find a 9.5 percentage point (38%) increase. In contrast, no such increase is observed for the most urgent patients, suggesting hospitals strategically admit more low-acuity patients at night to increase profits. Regarding health outcomes, we detect a small but significant increase in hospitalization rates for nighttime admissions, indicating a potential crowding-out effect. However, the policy has minimal impact on hospital capacity, treatment intensity, length of stay, hospitalization costs, or patient mortality. Lastly, we find no evidence of substitution between emergency and primary care, suggesting that observed patterns are driven by hospital rather than patient behaviors.

The Impact of Prenatal Care on Maternal and Infant Health: Evidence from the SARS Epidemic in Taiwan 

with Shin-Yi Chou, Hsien-Ming Lien 

This paper overcomes the challenge of estimating the benefits of prenatal care by exploring a 20% reduction in prenatal care use during the 2003 SARS epidemic in Taiwan. Adopting social learning effects in response to the widespread panic, we instrument a mother's reduction in prenatal visits with the change in average visits among their peer groups. Using administrative data, we find that prenatal care significantly lowered the likelihood of low birth weight, preterm birth, and neonatal and infant mortality. When stratifying samples by parity, the effects on mortality only persist among the firstborn, suggesting that information is especially important for first-time mothers. However, we find no impact on maternal complications during delivery.