2018, No. 1

Abstracts of Selected Recent NBER Working Papers

Longitudinal Determinants of End-of-Life Wealth Inequality
James M. Poterba, Steven F. Venti, David A. Wise

This paper examines inequality in end-of-life wealth and the factors that contribute to individuals reaching this life stage with few financial resources. It analyzes repeated cross-sections of the Health and Retirement Study, as well as a small longitudinal sample of individuals observed both at age 65 and shortly before death. Most of those who die with little wealth had little wealth at retirement. There is strong persistence over time in the bottom tail of the wealth distribution, but the probability of having low wealth increases slowly with age after age 65. Those with low lifetime earnings are much more likely to report low wealth at retirement, and to die with little wealth, than their higher-earning contemporaries. The onset of a major medical condition and the loss of a spouse increase in the probability of falling into the low wealth category at advanced ages, although these factors appear to contribute to wealth decline for only a small fraction of those who had modest wealth at age 65 but low wealth at the time of death.

The Impact of State Medical Marijuana Laws on Social Security Disability Insurance and Workers' Compensation Benefit Claiming
Johanna Catherine Maclean, Keshar M. Ghimire, Lauren Hersch Nicholas

We study the effect of state medical marijuana laws (MMLs) on Social Security Disability Insurance (SSDI) and Workers' Compensation (WC) claiming. We use data on benefit claiming drawn from the 1990 to 2013 Current Population Survey coupled with a differences-in-differences design. We find that passage of an MML increases SSDI, but not WC, claiming on both the intensive and extensive margins. Post-MML the propensity to claim SSDI increases by 0.27 percentage points (9.9%) and SSDI benefits increase by 2.6%. We identify heterogeneity by age and the manner in which states regulate medical marijuana. Our findings suggest an unintended consequence of MMLs: increased reliance on costly social insurance programs among working age adults.

Does Multispecialty Practice Enhance Physician Market Power?
Laurence C. Baker, M. Kate Bundorf, Daniel P. Kessler

In markets for health services, vertical integration — common ownership of producers of complementary services — may have both pro- and anti-competitive effects. Despite this, no empirical research has examined the consequences of multispecialty physician practice — a common and increasing form of vertical integration — for physician prices. We use data on 40 million commercially insured individuals from the Health Care Cost Institute to construct indices of the price of a standard office visit to general-practice and specialist physicians for the years 2008-12. We match this to measures of the characteristics of physician practices and physician markets based on Medicare Part B claims, aggregating physicians into practices based on their receipt of payments under a common Taxpayer Identification Number. Holding fixed the degree of competition in their own specialty, we find that generalist physicians charge higher prices when they are integrated with specialist physicians, and that the effect of integration is larger in uncompetitive specialist markets. We find the same thing in the reciprocal setting — specialist prices are higher when they are integrated with generalists, and the effect is stronger in uncompetitive generalist markets. Our results suggest that multispecialty practice has anticompetitive effects.

Therapeutic Translation in the Wake of the Genome
Manuel I. Hermosilla, Jorge A. Lemus

The completion of the Human Genome Project (“HGP”) led many scientists to predict a swift revolution in human therapeutics. Despite large advances, however, this revolution has been slow to materialize. We investigate the hypothesis that this slow progress may stem from the large amounts of biological complexity unveiled by the Genome. Our test relies on a disease-specific measure of biological complexity, constructed by drawing on insights from Network Medicine (Barabasi et al., 2011). According to this measure, more complex diseases are those associated with a larger number of genetic associations, or with higher centrality in the Human Disease Network (Goh et al., 2007). With this measure in hand, we estimate the rate of translation of new science into early stage drug innovation by focusing on a leading type of genetic epidemiological knowledge (Genome-Wide Association Studies), and employing standard methods for the measurement of R&D productivity. For less complex diseases, we find a strong and positive association between cumulative knowledge and the amount of innovation. This association weakens as complexity increases, becoming statistically insignificant at the extreme. Our results therefore suggest that biological complexity is in part responsible for the slower-than-expected unfolding of the therapeutical revolution set in motion by the HGP.

Medicaid and Financial Health
Kenneth Brevoort, Daniel Grodzicki, Martin B. Hackmann

This paper investigates the effects of the Medicaid expansion provision of the Affordable Care Act (ACA) on households' financial health. Our findings indicate that, in addition to reducing the incidence of unpaid medical bills, the reform provided substantial indirect financial benefits to households. Using a nationally representative panel of 5 million credit records, we find that the expansion reduced unpaid medical bills sent to collection by $3.4 billion in its first two years, prevented new delinquencies, and improved credit scores. Using data on credit offers and pricing, we document that improvements in households' financial health led to better terms for available credit valued at $520 million per year. We calculate that the financial benefits of Medicaid double when considering these indirect benefits in addition to the direct reduction in out-of-pocket expenditures.

Older Americans Would Work Longer If Jobs Were Flexible
John Ameriks, Joseph S. Briggs, Andrew Caplin, Minjoon Lee, Matthew D. Shapiro, Christopher Tonetti

Older Americans, even those who are long retired, have strong willingness to work, especially in jobs with flexible schedules. For many, labor force participation near or after normal retirement age is limited more by a lack of acceptable job opportunities or low expectations about finding them than by unwillingness to work longer. This paper establishes these findings using an approach to identification based on strategic survey questions (SSQs) purpose-designed to complement behavioral data. These findings suggest that demand-side factors are important in explaining late-in-life labor market behavior and may be the most appropriate target for policy aimed at promoting working longer.

Identifying Sources of Inefficiency in Health Care
Amitabh Chandra, Douglas O. Staiger

In medicine, the reasons for variation in treatment rates across hospitals serving similar patients are not well understood. Some interpret this variation as unwarranted, and push standardization of care as a way of reducing allocative inefficiency. However, an alternative interpretation is that hospitals with greater expertise in a treatment use it more because of their comparative advantage, suggesting that standardization is misguided. We develop a simple economic model that provides an empirical framework to separate these explanations. Estimating this model with data on treatments for heart attack patients, we find evidence of substantial variation across hospitals in both allocative inefficiency and comparative advantage, with most hospitals overusing treatment in part because of incorrect beliefs about their comparative advantage. A stylized welfare-calculation suggests that eliminating allocative inefficiency would increase the total benefits from this treatment by about a third.

Service-level Selection: Strategic Risk Selection in Medicare Advantage in Response to Risk Adjustment
Sungchul Park, Anirban Basu, Norma Coe, Fahad Khalil

The Centers for Medicare and Medicaid Services (CMS) has phased in the Hierarchical Condition Categories (HCC) risk adjustment model during 2004-06 to more accurately estimate capitated payments to Medicare Advantage (MA) plans to reflect each beneficiary's health status. However, it is debatable whether the CMS-HCC model has led to strategic evolutions of risk selection. We examine the competing claims and analyze the risk selection behavior of MA plans in response to the CMS-HCC model. We find that the CMS-HCC model reduced the phenomenon that MA plans avoid high-cost beneficiaries in traditional Medicare plans, whereas it led to increased disenrollment of high-cost beneficiaries, conditional on illness severity, from MA plans. We explain this phenomenon in relation to service-level selection. First, we show that MA plans have incentives to effectuate risk selection via service-level selection, by lowering coverage levels for services that are more likely to be used by beneficiaries who could be unprofitable under the CMS-HCC model. Then, we empirically test our theoretical prediction that compared to the pre-implementation period (2001–03), MA plans have raised copayments disproportionately more for services needed by unprofitable beneficiaries than for other services in the post-implementation period (2007-09). This induced unprofitable beneficiaries to voluntarily disenroll from their MA plans. Further evidence supporting this selection mechanism is that those dissatisfied with out-of-pocket costs were more likely to disenroll from MA plans. We estimate that such strategic behavior led MA plans to save $5.2 billion by transferring the costs to the federal government.

Family Health Behaviors
Itzik Fadlon, Torben Heien Nielsen

This paper studies how health behaviors and investments are shaped through family spillovers. Leveraging administrative health care data, we identify the effects of health shocks to individuals on their family members' consumption of preventive care and health-related behaviors. Our identification strategy utilizes the timing of shocks to construct counterfactuals for affected households using households that experience the same shock but a few years in the future. We find that spouses and adult children immediately increase their health investments and improve their health behaviors in response to family shocks, and that these effects are both significant and persistent. Notably, we show that these spillover effects are far-reaching and cascade to siblings, step-children, sons and daughters in-law, and even "close" coworkers. While some responses are consistent with learning new information about one's own health, evidence from cases where shocks are likely uninformative points to salience as a major operative explanation. Our results underscore the importance of one's family and social network for models of health behaviors and have potential implications for policies that aim to improve population health.

The Effect of Primary Care Visits on Health Care Utilization: Findings from a Randomized Controlled Trial
Cathy J. Bradley, David Neumark, Lauryn Saxe Walker

We conducted a randomized controlled trial, enrolling low-income uninsured adults to determine whether cash incentives are effective at encouraging a primary care provider (PCP) visit, and at lowering utilization and spending. Subjects were randomized to four groups: untreated controls, and one of three incentive arms with incentives of $0, $25, or $50 for visiting a PCP within six months of group assignment. Compared to the untreated controls, subjects in the incentive groups were more likely to have a PCP visit in the initial six months. They had fewer ED visits in the subsequent six months, but outpatient visits did not decline. We also used the exogenous variation generated by the experiment to obtain causal evidence on the effects of a PCP visit. We observed modest reductions in emergency department use and increased outpatient use, but no reductions in overall spending.

The Power of Working Longer
Gila Bronshtein, Jason Scott, John B. Shoven, Sita N. Slavov

This paper compares the relative strengths of working longer vs. saving more in terms of increasing a household's affordable, sustainable standard of living in retirement. Both stylized households and actual households from the Health and Retirement Study are examined. We assume that workers commence Social Security benefits when they retire. The basic result is that delaying retirement by 3-6 months has the same impact on the retirement standard of living as saving an additional one-percentage point of labor earnings for 30 years. The relative power of saving more is even lower if the decision to increase saving is made later in the work life. For instance, increasing retirement saving by one percentage point ten years before retirement has the same impact on the sustainable retirement standard of living as working a single month longer. The calculations of the relative power of working longer and saving more are done for a wide range of realized rates of returns on saving, for households with different income levels, and for singles as well as married couples. The results are quite invariant to these circumstances.

What Do Workplace Wellness Programs Do? Evidence from the Illinois Workplace Wellness Study
Damon Jones, David Molitor, Julian Reif

Workplace wellness programs cover over 50 million workers and are intended to reduce medical spending, increase productivity, and improve well-being. Yet, limited evidence exists to support these claims. We designed and implemented a comprehensive workplace wellness program for a large employer with over 12,000 employees, and randomly assigned program eligibility and financial incentives at the individual level. Over 56 percent of eligible (treatment group) employees participated in the program. We find strong patterns of selection: during the year prior to the intervention, program participants had lower medical expenditures and healthier behaviors than non-participants. However, we do not find significant causal effects of treatment on total medical expenditures, health behaviors, employee productivity, or self-reported health status in the first year. Our 95% confidence intervals rule out 78 percent of previous estimates on medical spending and absenteeism. Our selection results suggest these programs may act as a screening mechanism: even in the absence of any direct savings, differential recruitment or retention of lower-cost participants could result in net savings for employers.

NBER Working Papers on Health and Aging
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