Medicaid Managed Care and Emergency Department Utilization: A North Carolina Analysis
by Temitope Ayokunmi Ojo
Abstract
In July 2021, North Carolina Medicaid switched from a traditional fee-for-service model to a Medicaid managed care (MMC) network. This thesis explores the effect of this policy change on Emergency Department (ED) utilization for Medicaid beneficiaries in North Carolina. A linear difference-in-difference model was used to estimate the change in ED visits between the treatment group, Medicaid beneficiaries, and two control groups, non-Medicaid 19–64-year-olds and 65+ NC residents. The results indicate a statistically significant decline in ED visits, about 11% decline from pre-policy visit rates, for Medicaid beneficiaries after the mandatory switch to managed care. The reduction in visits was most persistent for those related to chronic condition treatment. Furthermore, we find evidence consistent with both medical care disruption and better management of health as drivers of the decline in ED visits. Determining the cause of these patterns should be explored by deeper analyses of trends in other healthcare delivery avenues (i.e. PCP appointments or hospital admissions) post-policy implementation.
Professor M. Kate Bundorf, Faculty Advisor
Professor Grace Kim, Seminar Advisor
JEL Codes: I11, I13, I18
Keywords: Medicaid, Insurance, Emergency Department
Alcohol Use and Assault: Regression Discontinuity Evidence from the Minimum Legal Drinking Age
by Maggie Hu
Abstract
While it has long been observed that alcohol consumption is a risk factor for violence, the economics literature has up until recently provided minimal persuasive evidence regarding the causal nature of this relationship. In this study, we employ a regression discontinuity (RD) framework to examine how arrest and victimization rates from assault change at age 21, the U.S. minimum legal drinking age (MLDA-21). Utilizing annual FBI arrest data from the past 36 years since 1988, when the last states adopted the MLDA-21, we estimate that for both males and females, reaching the MLDA increases arrest rates for aggravated and other simple assaults by 5 – 8%, with the aggravated assault effect for females restricted to the latter half of the sample period. Analogous effects at slightly older ages are small and insignificant, as well as the effects for demographic and population characteristics expected to trend smoothly across the MLDA-21 threshold. We extend our analysis of assault-related violence by assessing victimization outcomes, particularly the effect of the MLDA-21 nonfatal injury, by leveraging emergency department (ED) data from the CDC’s Web-based Injury Statistics and Query Reporting System (WISQARS) spanning the period 2001–2022. Notably, we observe that ED visits for “struck by or against” assaults rise significantly by 7–10%, indicating increased participation in violent altercations and increased risk of victimization upon obtaining legal access to alcohol. Taken together, these results suggest that alcohol use increases aggression and violent behavior, the consequences of which thereby represent criminal justice and public health costs that would be exacerbated by lowering the MLDA.
Professor Jeffrey DeSimone, Faculty Advisor
JEL Codes: I18, I12, K0, K32
Keywords: Health Economics, Alcohol Policy, Education and Welfare
The Effect of Gun Prevalence on the Occurrence of School Shootings
by Abigail Ullendorff
Abstract
This paper studies how gun prevalence, represented by federal firearm background checks, affects the occurrence of school shootings. While precedent literature has estimated adverse effects of school shootings on exposed children, including reductions in mental health, academic achievement, and labor market earnings, few studies have attempted to identify factors that influence school shooting frequency in the first place. The analysis sample is an annual state panel of shootings during 2000-2021, constructed from the proprietary K-12 School Shooting Database as well as from data on background checks, demographic characteristics, economic conditions, and measures of violence and mental health status. Estimates from difference-in-differences regressions that include state and year by-census region fixed effects and state-specific linear trends indicate a positive relationship between gun prevalence and school shootings, particularly when the dependent variable is specified as a binary indicator of multiple school shootings having occurred. Results are robust to using the annual shooting count or its quartic root, an indicator that a shooting occurred, Poisson regressions of school shooting count models, and quadratic state trends as additional controls. Several types of shootings, including targeted, elementary school, high school, and deadly shootings, increase in frequency and/or likelihood when gun prevalence rises.
Professor Jeffrey DeSimone, Faculty Advisor
Professor Grace Kim, Faculty Advisor
JEL Codes: I18, I29, K42
Impact of Medicare Advantage Supplemental Benefit Expansion on Startup Funding
by Judy Tianhong Zhong
Abstract
In 2018, the Center for Medicare and Medicaid Services (CMS) announced that they would expand the supplemental benefits that can be included in Medicare Advantage (MA) plans. The goal was to encourage insurers to innovate and test new benefit offerings that could improve health outcomes and reduce healthcare spending. A key player in this transformation is the MA vendor that provides supplemental benefit offerings to insurance plans, but this market is rather underdeveloped. To assess the implementation of this supplemental benefit expansion, this study examines the flow of funding into the emerging market of MA vendors. This paper uses a longitudinal approach and Crunchbase data on funding for 79,004 firms from 2014 to 2018 to determine whether there is a significant jump in funding toward MA vendors with supplemental benefit services following the policy change. The results show that both the average amount of funding per deal and the number of deals a MA vendor firm receives significantly increased following the expansion when compared with all other firms. This suggests that the policy may have been successful in promoting the development of the MA vendors market and the innovation of benefit offerings as more funding goes towards these companies.
Kate Bundorf, Faculty Advisor
David Ridley, Faculty Advisor
Michelle Connolly, Faculty Advisor
JEL Codes: I1; I11; I18
Impact of Language Access Laws on LEP Infant Mortality Rates
by Andrew Ryan Griffin
Abstract
Starting with Executive Order 13166 in 2000, the United States federal government
began to address the language disparity issues in health care. Around the same time, several
states have begun to pass language access (LA) legislation mandating translation and
interpretation services at hospitals for limited English proficient (LEP) individuals. This study
uses these multiple discontinuities to evaluate the effect of language access laws on infant
mortality rates, adequacy of care, Apgar scores, and the number of prenatal visits from the years
1995 to 2004 for limited English proficient families. I find ambiguous results of language access
laws positively impacting infant mortality rates or Apgar scores, but I find clear positive impacts
on the adequacy of care and the number of prenatal visits. These findings suggest that language
access laws have a clear effect on reducing barriers for limited English proficient mothers, and
improving the care mothers receive. Furthermore, there is limited evidence that it improves
infant health or outcomes, but the increase of prenatal visits and adequacy of care likely
indirectly leads to improving infant mortality rates and Apgar scores. More research is needed
into discovering how those mechanisms work and the costs of language services.
Professor Michelle Conolly, Faculty Advisor
JEL Codes: I10, I18, I19
The Effects of Leveraged Buyouts on Health Outcomes
by Robert Williams
Abstract
Private equity firms first began acquiring hospitals in the United States during the early 1990s, yet the effects of private equity ownership on patient outcomes and treatment costs are still not clear. Some argue that although private equity firms are adept at improving operating efficiencies and introducing managerial expertise, these cost-cutting measures may come at the expense of patient outcomes.
Because acute myocardial infarctions (AMIs) serve as proxies for patient outcomes and treatment costs, I collect information on 30-day mortality rates and Medicare reimbursements for treatments of AMIs at US Medicare-certified short-term acute care general hospitals from 2014 to 2019. This paper uses fixed effects models to analyze the impact of leveraged buyouts, relative to strategic acquisitions, on patient outcomes. After integrating both hospital and time fixed effects, I find that private equity ownership does not lead to significant changes in Medicare reimbursements or mortality rates for AMI treatments.
Professor Ryan McDevitt, Faculty Advisor
Professor Grace Kim, Faculty Advisor
Professor Michelle Connolly, Faculty Advisor
JEL Codes: I0, I110, G340
The Effects of Health IT Innovation on Throughput Efficiency in the Emergency Department
by Michael Levin
Abstract
Overcrowding in United States hospitals’ emergency departments (EDs) has been identified as a significant barrier to receiving high-quality emergency care, resulting from many EDs struggling to properly triage, diagnose, and treat emergency patients in a timely and effective manner. Priority is now being placed on research that explores the effectiveness of possible solutions, such as heightened adoption of IT to advance operational workflow and care services related to diagnostics and information accessibility, with the goal of improving what is called throughput efficiency. However, high costs of technological process innovation as well as usability challenges still impede wide-spanning and rapid implementation of these disruptive solutions. This paper will contribute to the pursuit of better understanding the value of adopting health IT (HIT) to improve ED throughput efficiency.
Using hospital visit data, I investigate two ways in which ED throughput activity changes due to increased HIT sophistication. First, I use a probit model to estimate any statistically and economically significant decreases in the probability of ED mortality resulting from greater HIT sophistication. Second, my analysis turns to workflow efficiency, using a negative binomial regression model to estimate the impact of HIT sophistication on reducing ED waiting room times. The results show a negative and statistically significant (p < 0.01) association between the presence of HIT and the probability of mortality in the ED. However, the marginal impact of an increase in sophistication from basic HIT functionality to advanced HIT functionality was not meaningful. Finally, I do not find a statistically significant impact of HIT sophistication on expected waiting room time. Together, these findings suggest that although technological progress is trending in the right direction to ultimately have a wide-sweeping impact on ED throughput, more progress must be made in order for HIT to directly move the needle on confronting healthcare’s greatest challenges.
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Advisors: Michelle Connolly, Ryan McDevitt | JEL Codes: I1, I18, O33
The Impact of Medicare Nonpayment: A Quasi-Experimental Approach
By Audrey Kornkven
In October 2008, a provision of the Deficit Reduction Act of 2005 known as Medicare “Nonpayment” went into effect, eliminating reimbursement for the marginal costs of preventable hospital-acquired conditions in an effort to correct perverse incentives in hospitals and improve patient safety. This paper contributes to the existing debate surrounding Nonpayment’s efficacy by considering varying degrees of fiscal pressure among hospitals; potential impacts on healthcare utilization; and differences between Medicare and non-Medicare patient populations. It combines data on millions of hospital discharges in New York from 2006-2010 with hospital-, hospital referral region-, and county-level data to isolate the policy’s impact. Analysis exploits the quasi-experimental nature of Nonpayment via difference-in-differences with Mahalanobis matching and fuzzy regression discontinuity designs. In line with results from Lee et al. (2012), Schuller et al. (2013), and Vaz et al. (2015), this paper does not find evidence that Nonpayment reduced the likelihood that Medicare patients would develop a hospital-acquired condition, and concludes that the policy is not likely the success claimed by policymakers. Results also suggest that providers may select against unprofitable Medicare patients when possible, and are likely to vary in their responses to financial incentives. Specifically, private non-profit hospitals appear to have been most responsive to the policy. These findings have important implications for pay-for-performance initiatives in American healthcare.
Advisors: Professor Charles Becker, Professor Frank Sloan, Professor Grace Kim| JEL Codes: I1, I13, I18
Assessing the Impacts of an Aging Population on Rising Healthcare and Pharmaceutical Expenditures within the United States
By Rahul Sharma
This paper studies the impact of aging on rising healthcare and pharmaceutical expenditures in the United States with the goal of contextualizing the future burden of public health insurance on the government. Precedent literature has focused on international panels of multiple countries and hasn’t identified significant correlation between age and healthcare expenditures. This paper presents a novel approach of identifying this correlation by using a US sample population to determine if age impacts an individual’s consumption of healthcare services and goods. Results suggest that age has a significant impact on healthcare and pharmaceutical expenditures across private and public insurance.
Advisors: Gilliam D. Saunders-Schmidler and Grace Kim | JEL Codes: H51, H53, I12, I13, I18, I38
The Effect of Competition on Strategic Discharge at Long-Term Acute-Care Hospitals
By Michael Karamardian
Because Medicare’s prospective payment system for long-term acute-care hospitals (LTCHs) makes a large lump-sum form of payment once patients reach a minimum length-ofstay threshold, LTCHs have a unique opportunity to maximize profits by strategically discharging patients as soon as the payment is received. This analysis explores how the level of competition between LTCHs in geographic markets affects the probability of a patient being strategically discharged. The results show that patients at LTCHs in more competitive markets have a lower probability of being strategically discharged than at those in less competitive markets, suggesting increased competition could help save Medicare funding.
Advisors: Kent Kimbrough and James Roberts | JEL Codes: D22, I11, I18
