Working Papers

Provider effects in antibiotic prescribing: Evidence from physician exits
BSE Discussion Paper, Nr. 18 (with Hannes Ullrich)
Accepted at Journal of Human Resources

Abstract In the fight against antibiotic resistance, reducing antibiotic consumption while preserving healthcare quality presents a critical health policy challenge. We investigate the role of practice styles in patients’ antibiotic intake using exogenous variation in patient-physician assignment. Practice style heterogeneity explains 49% of the differences in overall antibiotic use and 83% of the differences in second-line antibiotic use between primary care providers. We find no evidence that high prescribing is linked to better treatment quality or fewer adverse health outcomes. Policies improving physician decision-making, particularly among high-prescribers, may be effective in reducing antibiotic consumption while sustaining healthcare quality.

The role of physician altruism in the physician-industry relationship
Draft available on request (with Anirban Basu, Lawrence Casalino, and Jing Li)

Abstract Altruism is a key professional norm that underlies the physician's role as a representative agent for patients. However, physician behavior can be influenced when private gains enter the objective function. We study the relationship between altruism and physicians' receipt of financial benefits from pharmaceutical manufacturers, as well as the extent to which altruism mitigates physicians' responsiveness to these industry payments. We combine data on altruistic preferences for 280 physicians, identified using a revealed preference economic experiment, with information on their receipt of monetary and in-kind transfers from pharmaceutical firms along with drug prescription claims data. Less altruistic physicians receive, on average, 2,184 USD (95% CI: 979.3--3,388.5) higher industry transfers, translating to 254% more in monetary value, compared to physicians with stronger altruistic preferences. Moreover, we observe that industry transfers are associated with higher overall drug costs and brand prescribing rates; however, these correlations are predominantly driven by physicians with less altruistic preferences. We find limited evidence that patient vulnerability moderates industry influences among less altruistic physicians. Our results indicate that altruism is an important determinant of physicians’ relationships with and responses to industry benefits.


Assessing the value of data for prediction policies: The case of antibiotic prescribing
Economics Letters, Vol. 213, 110360, 2022 (with Michael Allan Ribers and Hannes Ullrich)

Abstract We quantify the value of data for the prediction policy problem of reducing antibiotic prescribing to curb antibiotic resistance. Using varying combinations of administrative data, we evaluate machine learning predictions for diagnosing bacterial urinary tract infections and the outcomes of prescription rules based on these predictions. Simple patient demographics improve prediction quality substantially but larger reductions in prescribing can be achieved by making use of rich health data. Our results suggest decreasing returns to data for prediction quality and increasing returns for policy outcomes. Hence, data needs for prediction policy problems must be assessed based on the policy objective and not only on prediction quality.

The effect of a ban on gender-based pricing on risk selection in the German health insurance market
Health Economics, Vol. 29(1), pp. 3-17, 2020 (with Martin Salm)

Abstract Starting from December 2012, insurers in the European Union were prohibited from charging gender‐discriminatory prices. We examine the effect of this unisex mandate on risk segmentation in the German health insurance market. Although gender used to be a pricing factor in Germany's private health insurance (PHI) sector, it was never used as a pricing factor in the social health insurance (SHI) sector. The unisex mandate makes PHI relatively more attractive for women and less attractive for men. Based on data from the German socio‐economic panel, we analyze how the unisex mandate affects the difference between women and men in switching rates between SHI and PHI. We find that the unisex mandate increases the probability of switching from SHI to PHI for women relative to men. On the other hand, the unisex mandate has no effect on the gender difference in switching rates from PHI to SHI. Because women have on average higher health care expenditures than men, our results imply a worsening of the PHI risk pool and an improvement of the SHI risk pool. Our results demonstrate that regulatory measures such as the unisex mandate can affect risk selection between public and private health insurance sectors.

Work in Progress

The causal effect of antibiotic prescribing on population antibiotic resistance
(with Michael Allan Ribers, Hannes Ullrich, Barbara Juliane Holzknecht, Jonas Bredtoft Boel, Jette Brommann Kornum, and Michael Pedersen)