+ The Medicaid Expansions of 2014 Increased Overall and Early Stage Cancer Diagnoses (with John Cawley, Kosali Simon, and Lindsay Sabik, American Journal of Public Health)

Objectives: To determine whether the 2014 Medicaid expansions facilitated by the Affordable Care Act (ACA) impacted early cancer diagnosis for non-elderly adults. Methods: Using SEER Cancer Registry data from 2010 through 2014, we estimated a difference-in-differences model of cancer diagnosis rates, both overall and by stage, comparing changes in county-level diagnosis rates in states that expanded Medicaid in 2014 to those that did not expand Medicaid. Results: Among the 611 counties in this study, overall cancer diagnoses increased by 8.0 per 100,000 population (95% CI, 0.3 to 15.6) or 3.4%. Early stage diagnoses increased by 9.0 per 100,000 population (95% CI, 3.2 to 14.8) or 6.4%. Late stage diagnoses did not change significantly. Conclusions: In their first year, Medicaid expansions were associated with an increase in cancer diagnosis, particularly at the early stage. Public Health Implications: Expanding public health insurance may be an avenue for improving cancer detection, which is associated with improved patient outcomes, including reduced mortality.

Press Coverage: US News & World Report, Philadelphia Inquirer, Pittsburgh Post-Gazette, West Virginia Public Radio, Doctors Lounge, American Journal of Managed Care, Healio, EurekAlert


+ Changes in Insurance Coverage Among Cancer Patients After the Affordable Care Act (with Lindsay Sabik, Kosali Simon, and Benjamin Sommers, JAMA Oncology)

The Affordable Care Act (ACA) has reduced uninsurance to an historic low. Debate continues about potential changes to the law, which could affect coverage for millions, particularly those with pre-existing conditions. Meanwhile, cancer is the leading cause of death among Americans under age 65. Cancer treatment is often unaffordable for uninsured patients, and some studies suggest expanding insurance could improve cancer diagnosis, treatment, and outcomes. Our objective was to quantify changes in health insurance under the ACA among patients newly diagnosed with cancer.

Press coverage: ABC News, US News & World Report, Los Angeles Times, MSN, Reuters, EurekAlert,, Oncology Nurse Advisor, Medical Xpress, Newswise, EHE + Me, Doctors Lounge, Health Medicine Network, MedIndia, Science Newsline, Medscape, Health Day, Medical Research, Healio


Before 2014, the primary path to Medicaid eligibility for non-elderly childless adults was the Supplemental Security Income program (SSI). The SSI program typically confers immediate Medicaid eligibility to adults with a work-limiting disability, low income, and limited assets. After 2014, in the 32 states and DC that expanded Medicaid, low-income adults became eligible for Medicaid without having to obtain “disabled” status. In the non-expansion states, SSI (which allows for lower earnings limits than the 2014 Medicaid expansion) remained the primary avenue for non-elderly childless adults to obtain Medicaid. We use data from the American Community Survey and the Social Security Administration to estimate the impact of the Medicaid expansion on SSI participation. We find that in states that expanded Medicaid, participation in the SSI program decreased by about 3 percent relative to pre-expansion levels. This suggests Medicaid expansion may reduce SSI participation.

Press coverage: Wisconsin Public Radio, Indiana Public Radio, EurekAlert, Medical XPress


+ Medicaid Expansion under the Affordable Care Act and Insurance Coverage in Rural and Urban Areas (with Kosali Simon and Michael Hendryx, Journal of Rural Health)

Purpose: To analyze the differential rural-urban impacts of the Affordable Care Act Medicaid expansion on low-income childless adults’ health insurance coverage. Methods: Using data from the American Community Survey years 2011-2015, we conducted a difference-in-differences regression analysis to test for changes in the probability of low-income childless adults having insurance in states that expanded Medicaid versus states that did not expand, in rural versus urban areas. Analyses employed survey weights, adjusted for covariates, and included a set of falsification tests as well as sensitivity analyses. Findings: Medicaid expansion under the Affordable Care Act increased the probability of Medicaid coverage for targeted populations in rural and urban areas, with a significantly greater increase in rural areas (P < .05), but some of these gains were offset by reductions in individual purchased insurance among rural populations (P < .01). Falsification tests showed that the insurance increases were specific to low-income childless adults, as expected, and were largely insignificant for other populations. Conclusions: The Medicaid expansion increased the probability of having “any insurance” for the pooled urban and rural low-income populations, and it specifically increased Medicaid coverage more in rural versus urban populations. There was some evidence that the expansion was accompanied by some shifting from individual purchased insurance to Medicaid in rural areas, and there is a need for future work to understand the implications of this shift on expenditures, access to care and utilization.


+ The Impact of Health Insurance on Preventive Care and Health Behaviors: Evidence from the First Two Years of the ACA Medicaid Expansions (with Kosali Simon and John Cawley, Journal of Policy Analysis and Management)

The U.S. population receives suboptimal levels of preventive care and has a high prevalence of risky health behaviors. One goal of the Affordable Care Act (ACA) was to increase preventive care and improve health behaviors by expanding access to health insurance. This paper estimates how the ACA-facilitated state-level expansions of Medicaid in 2014 affected these outcomes. Using data from the Behavioral Risk Factor Surveillance System, and a difference-in-differences model that compares states that did and did not expand Medicaid, we examine the impact of the expansions on preventive care (e.g., dental visits, immunizations, mammograms, cancer screenings), risky health behaviors (e.g., smoking, heavy drinking, lack of exercise, obesity), and self-assessed health. We find that the expansions increased insurance coverage and access to care among the targeted population of low-income childless adults. The expansions also increased use of certain forms of preventive care, but there is no evidence that they increased ex ante moral hazard (i.e., there is no evidence that risky health behaviors increased in response to health insurance coverage). The Medicaid expansions also modestly improved self-assessed health.

Press coverage: Newswise, UPI, Health Medicine Network, Healio, Science Daily, Becker's Hospital Review, Insurance News Net, EurekAlert, myScience, Breitbart, Medical XPress, Health Management Technology, IU Bloomington Newsroom, Indiana Daily Student, Cornell Chronicle, WVPE 88.1, WBOI 89.1, APPAM Public Policy News, Health Affairs Blog



+ Gains in Health Insurance Coverage Explain Variation in Democratic Vote Share in the 2016 Presidential Election (with Alex Hollingsworth, Aaron Carroll, John Cawley, and Kosali Simon) (under review)

The results of the 2016 Presidential election departed considerably from polling forecasts. Given the prominence of the Affordable Care Act in the election, we test whether changes in health insurance coverage at the county level correlate with changes in party vote share in the Presidential elections from 2008 through 2016. We find that a one percentage point increase in county health insurance coverage was associated with a 0.29 percentage point increase in the vote share of the Democratic Presidential candidate. We further find that these gains of the Democratic candidate came almost fully at the expense of the Republican (as opposed to third-party) Presidential candidates. We also estimate models separately for states that did and did not expand Medicaid and find no statistically significant impact of Medicaid expansion on Democratic vote share. Our results are consistent with the hypothesis that outcomes in health insurance markets played a role in the outcome of the 2016 Presidential election. The decisions made by the current administration, and how those decisions affect health insurance coverage and costs, may be important factors in future elections as well.

+ How Have Recent Health Insurance Expansions Affected Coverage Among Artist Occupations? (with Joanna Woronkowicz, Seth Freedman, and Kosali Simon) (under review)

Most US workers receive their health insurance through employers due to a combination of its favorable tax treatment, improved bargaining power, and reduced adverse selection concerns. This institutional structure, however, favors large employers and full-time workers, thus not all segments of the workforce enjoy the benefits of this system. Artists are especially disadvantaged relative to other sectors in the employment-based health insurance system as they tend to be self-employed workers and/or work on contractual bases. The Affordable Care Act (ACA), by expanding options for health insurance to those without offers from employers, represents an improvement particularly for occupations that favor self-employment, such as artists. We use large-scale survey data that identifies occupations and contains sufficient numbers of artists to study the impact of the ACA on the health insurance of these workers. We find that the 2010 Young Adult Mandate of the ACA increased employment related health insurance by 10.4 percentage points (ppts) (and any coverage by 6.5 ppts) for 21-25 year old artists, and that the Medicaid coverage rate of artists below the poverty level increased by 12.5 ppts (although its effects on any coverage are statistically imprecise) due to the state Medicaid expansion component of the ACA in 2014. Both these effects are significantly larger than for other workers. Our results thus indicate that recent health reforms have had important and larger effects on artist occupations than other worker populations in general.

+ Expanded Insurance Coverage Options are Associated with Increased Coverage for Workers without Access to Group Insurance (with Sandra Decker and Asako Moriya) (under review)

Health care reform seeks to improve insurance coverage and access to care. Since eligibility for public coverage and subsidized private coverage are often means-tested, adults with limited labor force attachment and therefore limited income may benefit the most. We used data for the period 2010-2016 from the National Health Interview Survey to assess changes in insurance coverage, access to care, and health care utilization after the 2014 implementation of Affordable Care Act provisions for non-workers compared to workers, including the self-employed and wage earners with and without offers of employer-sponsored insurance (ESI). We found that the self-employed and wage-earners without ESI offers had insurance gains equal to or greater than non-workers. They also had equal or greater improvements in access to care and the chance of having had a recent doctor visit. Gains for non-workers came primarily from Medicaid, while workers benefitted from Marketplace coverage.

+ Third Year of Evidence Shows Continuing Benefits of Medicaid Expansions (with John Cawley and Kosali Simon) (under review)

The effects of the 2014 state Medicaid expansions facilitated by the Affordable Care Act (ACA) are the subject of numerous studies that use the first two years of data (2014-15) after expansion. This article presents the first results based on a third year of post-expansion data that measure the nation-wide impact of the Medicaid expansions on access to care, preventive care, risky health behaviors, and self-assessed health.

+ The Impact of the Tennessee Medicaid Disenrollment on Rural vs. Urban Populations: An ACA Presage? (with Michael Hendryx and Kosali Simon)

Objective:To examine differential impacts of the Tennessee Medicaid disenrollment on insurance coverage, access to care, and self-assessed health for rural vs. urban, White vs. non-White, and male vs. female populations. Methods:We analyzed the 2001-09 Behavioral Risk Factors Surveillance System by geography, race/ethnicity, sex, year (2001-04 and 2006-09), state (Tennessee, Alabama, Arkansas, Georgia, Kentucky, and Virginia), and year-by-state interactions. We estimated difference-in-differences and triple differences regression models comparing outcomes in Tennessee to outcomes in control states, before and after the 2005 Medicaid disenrollment. Results:After the disenrollment, insurance coverage rates dropped more for rural people, White people, and women. Conclusions: While the overall coverage and access to care impacts of the Tennessee Medicaid disenrollment were negative, some groups were hurt more than others. Policy implications:At a time of policy uncertainty, our study provides suggestive evidence that large cutbacks in public insurance programs may particularly hurt rural, White, and female populations.


  • Impacts of State Alcohol Policies on Alcohol Purchases (with Christopher Carpenter)
  • Health Insurance, Price Changes, and the Demand for Pain Relief Drugs: Evidence from Medicare Part D
  • Consumption Effects of Health Insurance Expansions: Evidence from Scanner Data
  • Drugs and Diet: Ex-Ante Moral Hazard Effects of Prescription Drug Insurance
  • The Impact of Prescription Drug Insurance on Health Outcomes
  • Consolidation and Premiums in the Health Insurance Market (with Haizhen Lin)
  • PDMP Laws and Opioid Hospitalizations (with Seth Freedman, Alex Hollingsworth, & Kosali Simon)


+ 2018

Midwest Economic Association. "Consumption Effects of Health Insurance Expansions: Evidence from Scanner Data." March 2018. Chicago, IL.

+ 2017

IU/UofL/VU Health Economics and Policy Workshop. "Drugs and Diet: The Impact of Prescription Drug Coverage on Food Habits." December 2017. Louisville, KY.

Association for Public Policy Analysis and Management. "Consumption Effects of Health Insurance Expansions: Evidence from Scanner Data." November 2017. Chicago, IL.

Association for Public Policy Analysis and Management. "Are Prescription Drugs and Over-the-Counter Medicines Substitutes or Complements?: Evidence from Medicare Part D." November 2017. Chicago, IL.

Population Health Science Research Workshop. "The Medicaid Expansions of 2014 Increased Early Stage Cancer Diagnoses." (Poster) October 2017. Boston, MA.

International Health Economics Association. "Affordable Care Act Medicaid Expansion Led to Increased Early Stage Cancer Diagnoses." July 2017. Boston, MA.

AcademyHealth Annual Research Meeting. "Impact of Tennessee Medicaid Disenrollment in Rural Areas: An ACA Presage?." June 2017. New Orleans, LA.

AcademyHealth Health Economics Interest Group. "Expanded Insurance Coverage Options are Associated with Increased Coverage for Workers without Access to Group Insurance." (Best Poster Award) June 2017. New Orleans, LA.

Eastern Economic Association. "Medicaid Expansion Status and State Trends in Supplemental Security Income Program Participation." February 2017. New York, NY.

+ 2016

IU/UofL/VU Health Economics and Policy Workshop. "The Impact of Public Health Insurance Expansions on Over-the-Counter Purchases." December 2016. Bloomington, IN.

American Society of Health Economists. "The Impact of Health Insurance on Preventive Care and Health Behaviors: Evidence from the First Two Years of the ACA Medicaid Expansions." (Poster) June 2016. Philadelphia, PA.


+ 2017

Association for Public Policy Analysis and Management. "How Protected Classes in Medicare Part D Influence Drug Spending and Utilization: Evidence from the Synthetic Control Method." Presenting author: Courtney R. Yarbrough, Emory University. November 2017. Chicago, IL.

Association for Public Policy Analysis and Management. "Examining the Effect of the Affordable Care Act in Colorado on Access to Care, Financial Strain, Utilization and Health Status." Presenting author: Michael Hatch, American University. November 2017. Chicago, IL.

Association for Public Policy Analysis and Management. "US Family Firearm Ownership and Firearm-Related Child Mortality from 1976 to 2014." Presenting author: Kate C. Prickett, University of Chicago. November 2017. Chicago, IL.

International Health Economics Association. "Gains in Coverage in 2014, by Length of Time Uninsured." Presenting author: Salam Abdus, Agency for Healthcare Research and Quality. July 2017. Boston, MA.

Eastern Economic Association. "Does Medicaid Expansion Affect Employment Transitions." Presenting author: Erkmen G. Aslim, Lehigh University. February 2017. New York, NY.