Abstract

This paper examines how drug diversion influences the prescribing practices of physicians and the equilibrium health impacts of prescription medications. Focusing on the case of prescription opioids, a commonly prescribed and frequently diverted medication at the heart of the worst drug crisis in U.S. history, I design and estimate a model of physician behavior in the presence of a secondary market with patient search. To access prescription opioids for medical purposes or misuse, patients search over physicians on the legal primary market or turn to an illegal secondary market. Physicians, who care both about their impact on population health and their revenue from office visits, take into account the possibility that patients might resell their prescriptions on the secondary market when prescribing. The model demonstrates that the potential for diversion will tend to make strict physicians more hesitant in their prescribing while leading lenient prescribers to loosen their prescription thresholds, thereby exacerbating prescribing differences between more and less lenient physicians. Estimates reveal that the presence of a secondary market induces most physicians to be more careful in their prescribing, which brings prescriptions closer to their optimal level, but results in significant net harm due to the reallocation of prescriptions for abuse.

Trauma at School: The Impacts of Shootings on Students' Human Capital and Economic Outcomes (March 2024)
with Marika Cabral, Bokyung Kim, Maya Rossin-Slater, Hannes Schwandt
NBER Working Paper 28311
Revisions requested at Review of Economic Studies
Media coverage: Vox’s The Weeds, Marketplace, Probable Causation, Freakonomics M.D.

Abstract

We examine how shootings at schools—an increasingly common form of gun violence in the United States—impact the educational and economic trajectories of students. Using linked schooling and labor market data in Texas from 1992–2018, we compare within-student and across-cohort changes in outcomes following a shooting to those experienced by students at matched control schools. We find that school shootings increase absenteeism and grade repetition; reduce high school graduation, college enrollment, and college completion; and reduce employment and earnings at ages 24–26. We further find school-level increases in the number of leadership staff and reductions in retention among teachers and teaching support staff in the years following a shooting. The adverse impacts of shootings span student characteristics, suggesting that the economic costs of school shootings are universal.

The Effects of Competition on Physician Prescribing (October 2024)
with Janet Currie and Anran Li
NBER Working Paper 30889
Cited in the 2024 Economic Report of the President

Abstract

We ask how competition influences the prescribing practices of physicians. Law changes granting nurse practitioners (NPs) the ability to prescribe controlled substances without physician collaboration or oversight generate exogenous variation in competition. In response, we find that general practice physicians (GPs) significantly increase their prescribing of controlled substances such as opioids and controlled anti-anxiety medications. GPs also increase their co-prescribing of opioids and benzodiazepines, a practice that goes against prescribing guidelines. These effects are more pronounced in areas with more NPs per GP at baseline and are concentrated in physician specialties that compete most directly with NPs. Our findings are consistent with a simple model of physician behavior in which competition for patients leads physicians to move toward the preferences of marginal patients. These results demonstrate that more competition will not always lead to improvements in patient care and can instead lead to excessive service provision.

The Expansionary and Contractionary Supply-Side Effects of Health Insurance (November 2023)
with Eilidh Geddes
NBER Working Paper 31483

Abstract

We examine how health insurance expansions affect the entry and location decisions of health care providers in settings with both public and private health insurance that differ in provider reimbursement generosity. We first show theoretically that expansions of health insurance with relatively high, market-based prices (e.g., private insurance) should lead the supply side to expand, whereas expansions of insurance with low, administered prices (e.g., Medicaid coverage) can instead lead the supply side to contract. We test these predictions in the setting of retail clinics, where we exploit county-level changes in insurance coverage following the Affordable Care Act and 1,721 retail clinic entries and exits. Using two-way fixed effects and instrumental variable designs, we find that growth in private insurance leads to large growth in clinic entry, whereas clinic penetration is dampened by increases in Medicaid coverage. Further consistent with our theoretical model, the contrasting supply-side effects of private insurance and Medicaid expansions are concentrated in states with low provider reimbursements under Medicaid. Similar location patterns are observed among other types of health care clinics, including urgent care centers. While it has long been accepted that reductions in the prices paid by consumers following insurance expansions should lead the supply side to expand to meet increased demand (Arrow, 1963), our results demonstrate that whether health insurance expansions cause the supply side to expand or contract further depends on how the prices received by providers are affected.

Drivers of Racial Differences in C-Sections (August 2024)
with Adriana Corredor-Waldron and Janet Currie
NBER Working Paper 32891
Media coverage: NYTimes, Healthline, PBS, ParentData

Abstract

Black mothers with unscheduled deliveries are 25 percent more likely to deliver by C-section than non-Hispanic white mothers. The gap is highest for mothers with the lowest risk and is reduced by only four percentage points when controlling for observed medical risk factors, sociodemographic characteristics, hospital, and doctor or medical practice group. Remarkably, the gap disappears when the costs of ordering an unscheduled C-section are higher due to the unscheduled delivery occurring at the same time as a scheduled C-section. This finding is consistent with provider discretion—rather than differences in unobserved medical risk—accounting for persistent racial disparities in delivery method. The additional C-sections that take place for low-risk women when hospitals are unconstrained negatively impact maternal and infant health.


JOURNAL ARTICLES


ECONOMICS AND GENERAL INTEREST

The Impacts of Physician Payments on Patient Access, Use, and Health (online appendix)
with Diane Alexander
American Economic Journal: Applied Economics, 2024, 16(3): 142–177
Featured in the NBER Bulletin on Health

Abstract

We examine how supply-side health insurance generosity affects patient access, use, and health. Exploiting large, exogenous changes in Medicaid reimbursement rates for physicians, we find that increasing payments for new patient office visits reduces reports of providers turning away beneficiaries: closing the gap in payments between Medicaid and private insurers would reduce more than half of disparities in access among adults and would eliminate such disparities among children. We further find that higher physician reimbursement leads to more office visits, better self-reported health, and reduced school absenteeism among the program's beneficiaries.

Local Exposure to School Shootings and Youth Antidepressant Use (online appendix)
with Maya Rossin-Slater, Hannes Schwandt, Sam Trejo, and Lindsey Uniat
Proceedings of the National Academy of Sciences, 2020, 117(38): 23484–23489
Media coverage: Washington Post, Los Angeles Times, The Hill
Featured in the NBER Digest; cited in the Surgeon General’s Advisory on Firearm Violence

Abstract

While over 240,000 American students experienced a school shooting in the last two decades, little is known about the impacts of these events on the mental health of surviving youth. Using large-scale prescription data from 2006 to 2015, we examine the effects of 44 school shootings on youth antidepressant use in a difference-in-difference framework. We find that local exposure to fatal school shootings increases youth antidepressant use by 21.4 percent in the following two years. These effects are smaller in areas with a higher density of mental health providers who focus on behavioral, rather than pharmacological, interventions.

Check Up Before You Check Out: Retail Clinics and Emergency Room Use (online appendix)
with Diane Alexander and Janet Currie
Journal of Public Economics, 2019, 178
Media coverage: Vox's The Weeds, Freakonomics Radio, U.S. News & World Report

Abstract

Given concern about inefficient use of the emergency room (ER) increasing health care costs, we use all ER visits in New Jersey from 2006–2014 to examine the impacts of retail clinics on ER use in a difference-in-difference framework. We find that among people residing close to an open retail clinic, the rate of ER use falls by 3.3–13.4 percent for preventable conditions and 5.7– 12.0 percent for minor acute conditions, while a range of placebo conditions are not affected. Our estimates suggest annual cost savings of nearly $70 million from reduced ER use if retail clinics were readily available across New Jersey.

Food Deserts and the Causes of Nutritional Inequality (online appendix)
with Hunt Allcott, Rebecca Diamond, Jean-Pierre Dubé, Jessie Handbury, and Ilya Rahkovsky
Quarterly Journal of Economics, 2019, 134(4): 1793–1844
Subsumes working paper: Is the Focus on Food Deserts Fruitless? Retail Access and Food Purchases Across the Socioeconomic Spectrum (with Jessie Handbury and Ilya Rahkovsky)
Media coverage: The Atlantic, NYTimes Upshot, Chicago Policy Review, FiveThirtyEight, Forbes, Freakonomics

Abstract

We study the causes of “nutritional inequality”: why the wealthy eat more healthfully than the poor in the United States. Exploiting supermarket entry and household moves to healthier neighborhoods, we reject that neighborhood environments contribute meaningfully to nutritional inequality. We then estimate a structural model of grocery demand, using a new instrument exploiting the combination of grocery retail chains’ differing presence across geographic markets with their differing comparative advantages across product groups. Counterfactual simulations show that exposing low-income households to the same products and prices available to high-income households reduces nutritional inequality by only about ten percent, while the remaining 90 percent is driven by differences in demand. These findings counter the argument that policies to increase the supply of healthy groceries could play an important role in reducing nutritional inequality.

Abstract

We examine whether relaxing occupational licensing to allow nurse practitioners (NPs)—registered nurses with advanced degrees—to prescribe medication without physician oversight improves population mental health. Exploiting time-series variation in independent prescriptive authority for NPs from 1990 to 2014, we find that broadening prescriptive authority leads to improvements in self-reported mental health and decreases in mental health–related mortality. These improvements are concentrated in areas that are underserved by physicians and among populations that have difficulty accessing physician-provided care. Our results demonstrate that extending independent prescriptive authority to NPs can help mitigate physician shortages and extend care to disadvantaged populations

U.S. Employment and Opioids: Is There a Connection?
with Janet Currie and Jonas Jin
Research in Labor Economics, 2019, 47: 253–280
Media coverage: Bloomberg, Chicago Policy Review

Abstract

This paper uses quarterly county-level data from 2006–2014 to examine the direction of causality in the relationship between per capita opioid prescription rates and employment-to-population ratios. We first estimate models of the effect of per capita opioid prescription rates on employment-to-population ratios, instrumenting opioid prescriptions for younger ages using opioid prescriptions to the elderly. We find that the estimated effect of opioids on employment-to-population ratios is positive but small for women, while there is no relationship for men. We then estimate models of the effect of employment-to-population ratios on opioid prescription rates using a shift-share instrument, and find ambiguous results. Overall, our findings suggest that there is no simple causal relationship between economic conditions and the abuse of opioids. Therefore, while improving economic conditions in depressed areas is desirable for many reasons, it is unlikely on its own to curb the opioid epidemic.

Addressing the Opioid Epidemic: Is There a Role for Physician Education? (online appendix)
with Janet Currie
American Journal of Health Economics, 2018, 4(3): 383–410 
Media coverage: The Economist, CNN, NBC, Bloomberg, Vox's The Weeds, STAT
Featured in the ASHEcon Newsletter

Abstract

Using national data on opioid prescriptions written by physicians from 2006 to 2014, we uncover a striking relationship between opioid prescribing and medical school rank. Even within the same specialty and practice location, physicians who completed their initial training at top medical schools write significantly fewer opioid prescriptions annually than physicians from lower-ranked schools. Additional evidence suggests that some of this gradient represents a causal effect of education rather than patient selection across physicians or physician selection across medical schools. Altering physician education may therefore be a useful policy tool in fighting the current epidemic.


MEDICAL AND HEALTH POLICY

Enrollment Brokers Did Not Increase Medicaid Enrollment, 2008–18
with Becky Staiger, Anran Li, and Diane Alexander
Health Affairs, 2022, 41(9): 1333–1341

Abstract

Between 2008 and 2018, six states and Washington, D.C., began contracting with enrollment brokers to facilitate enrollment into Medicaid, joining the eighteen states that already had such contracts in place as of 2008. Using newly collected data covering all contracts between state Medicaid agencies and independent enrollment brokers during this period, we compared changes in Medicaid participation following the initiation of contracts with enrollment brokers with contemporaneous changes in Medicaid participation in states that never contracted with brokers. We found that contract initiation had no statistically significant effects on state-level Medicaid participation. We further found no evidence of other enrollment-related benefits, such as improved application processing times.

Prescribing of Opioid Analgesics and Buprenorphine for Opioid Use Disorder During the COVID-19 Pandemic
with Janet Currie, Hannes Schwandt, and Jonathan Zhang
JAMA Network Open, 2021, 4(4): e216147

Abstract

How has prescribing of opioid analgesics and buprenorphine for opioid use disorder (OUD) changed throughout the COVID-19 pandemic? Analyzing 452,691,261 prescriptions from 90,420,353 patients, we found that existing patients receiving opioid analgesics and buprenorphine for OUD generally maintained access to these medications during the COVID-19 pandemic. Opioid prescriptions for opioid-naive patients decreased briefly and then rebounded, while initiation of buprenorphine remained at a low rate through August 2020. Reductions in treatment entry may be associated with increased overdose deaths.

Trends in Drug Overdose Mortality in Ohio During the First 7 Months of the COVID-19 Pandemic
with Janet Currie, Hannes Schwandt, and Jonathan Zhang
JAMA Network Open (Peer-reviewed Research Letter), 2021, 4(4): e217112


OTHER WRITING


The Lasting Impacts of School Shootings on Youth Psychotropic Drug Use (online appendix)
with Max Pienkny, Maya Rossin-Slater, and Hannes Schwandt
AEA Papers and Proceedings, May 2024

The Lasting Consequences of School Shootings on the Students Who Survive Them
with Marika Cabral, Bokyung Kim, Maya Rossin-Slater, and Hannes Schwandt
The Conversation, May 2022

Eliminating Food Deserts Won’t Help Poorer Americans Eat Healthier
with Hunt Allcott and Jean-Pierre Dubé
The Conversation, December 2019

The Opioid Crisis: Tragedy, Treatments, and Trade-offs
SIEPR Policy Brief, February 2019

Research Roundup: What Does the Evidence Say About How to Fight the Opioid Epidemic?
with Jennifer Doleac and Anita Mukherjee
Brookings Institute, December 2018

A Closer Look at How the Opioid Epidemic Affects Employment
with Janet Currie
Harvard Business Review, August 2018

Evaluating the Economic Response to Japan's Earthquake
with David Weinstein
RIETI Policy Discussion Paper Series, February 2012