Education is strongly associated with better health and longer lives. However, the extent to which education causes health and longevity is widely debated. We develop a human capital framework to structure the interpretation of the empirical evidence and review evidence on the causal effects of education on mortality and its two most common preventable causes: smoking and obesity. We focus attention on evidence from randomized controlled trials, twin studies, and quasi-experiments. There is no convincing evidence of an effect of education on obesity, and the effects on smoking are only apparent when schooling reforms affect individuals’ track or their peer group, but not when they simply increase the duration of schooling. An effect of education on mortality exists in some contexts but not in others and seems to depend on (i) gender, (ii) the labor market returns to education, (iii) the quality of education, and (iv) whether education affects the quality of individuals’ peers.
Article
Titus Galama, Adriana Lleras-Muney, and Hans van Kippersluis
Article
Vincenzo Atella and Joanna Kopinska
New sanitation and health technology applied to treatments, procedures, and devices is constantly revolutionizing epidemiological patterns. Since the early 1900s it has been responsible for significant improvements in population health by turning once-deadly diseases into curable or preventable conditions, by expanding the existing cures to more patients and diseases, and by simplifying procedures for both medical and organizational practices. Notwithstanding the benefits of technological progress for the population health, the innovation process is also an important driver of health expenditure growth across all countries. The technological progress generates additional financial burden and expands the volume of services provided, which constitutes a concern from an economic point of view. Moreover, the evolution of technology costs and their impact on healthcare spending is difficult to predict due to the revolutionary nature of many innovations and their adoption. In this respect, the challenge for policymakers is to discourage overadoption of ineffective, unnecessary, and inappropriate technologies. This task has been long carried out through regulation, which according to standard economic theory is the only response to market failures and socially undesirable outcomes of healthcare markets left on their own. The potential welfare loss of a market failure must be confronted with the costs of regulatory activities. While health technology evolution delivers important value for patients and societies, it will continue to pose important challenges for already overextended public finances.
Article
Matteo M. Galizzi and Daniel Wiesen
The state-of-the-art literature at the interface between experimental and behavioral economics and health economics is reviewed by identifying and discussing 10 areas of potential debate about behavioral experiments in health. By doing so, the different streams and areas of application of the growing field of behavioral experiments in health are reviewed, by discussing which significant questions remain to be discussed, and by highlighting the rationale and the scope for the further development of behavioral experiments in health in the years to come.
Article
Florence Jusot and Sandy Tubeuf
Recent developments in the analysis of inequality in health and healthcare have turned their interest into an explicit normative understanding of the sources of inequalities that calls upon the concept of equality of opportunity. According to this concept, some sources of inequality are more objectionable than others and could represent priorities for policies aiming to reduce inequality in healthcare use, access, or health status.
Equality of opportunity draws a distinction between “legitimate” and “illegitimate” sources of inequality. While legitimate sources of differences can be attributed to the consequences of individual effort (i.e. determinants within the individual’s control), illegitimate sources of differences are related to circumstances (i.e. determinants beyond the individual’s responsibility).
The study of inequality of opportunity is rooted in social justice research, and the last decade has seen a rapid growth in empirical work using this literature at the core of its approach in both developed and developing countries. Empirical research on inequality of opportunity in health and healthcare is mainly driven by data availability. Most studies in adult populations are based on data from European countries, especially from the UK, while studies analyzing inequalities of opportunity among children are usually based on data from low- or middle-income countries and focus on children under five years old.
Regarding the choice of circumstances, most studies have considered social background to be an illegitimate source of inequality in health and healthcare. Geographical dimensions have also been taken into account, but to a lesser extent, and more frequently in studies focusing on children or those based on data from countries outside Europe. Regarding effort variables or legitimate sources of health inequality, there is wide use of smoking-related variables.
Regardless of the population, health outcome, and circumstances considered, scholars have provided evidence of illegitimate inequality in health and healthcare. Studies on inequality of opportunity in healthcare are mainly found in children population; this emphasizes the need to tackle inequality as early as possible.
Article
Jan C. van Ours
There are three main topics in research on the effects of work on health.
The first topic is workplace accidents where the main issues are reporting behavior and workplace safety policies. A worker seems to be less inclined to report a workplace accident for fear of job loss when unemployment is high or when the worker has a temporary contract that may not be renewed. Workplace safety legislation has intended to reduce the incidence and severity of workplace accidents but empirical evidence on this result is unclear.
The second topic is employment and health where the focus is on how job characteristics and job loss affect health, in particular mental health. Physically demanding jobs have negative health effects. The effects of working hours vary and the effects of job loss on physical and mental health are not uniform. Job loss seems to increase mortality.
The third topic concerns retirement and health. Retirement seems to have a negative effect on cognitive skills and short-term positive effects on overall health. Other than that, the effects are very inconsistent, that is, even with as clear a measure as mortality, it is not clear whether life expectancy goes up, goes down, or remains constant due to retirement.
Article
Daniel Eisenberg and Ramesh Raghavan
One of the most important unanswered questions for any society is how best to invest in children’s mental health. Childhood is a sensitive and opportune period in which to invest in programs and services that can mitigate a range of downstream risks for health and mental health conditions. Investing in such programs and services will require a shift from focusing not only on reducing deficits but also enhancing the child’s skills and other assets. Economic evaluation is crucial for determining which programs and services represent optimal investments. Several registries curate lists of programs with high evidence of effectiveness; many of these programs also have evidence of positive benefit-cost differentials, although the economic evidence is typically limited and uncertain. Even the programs with the strongest evidence are currently reaching only a small fraction of young people who would potentially benefit. Thus, it is important to understand and address factors that impede or facilitate the implementation of best practices. One example of a program that represents a promising investment is home visiting, in which health workers visit the homes of new parents to advise on parenting skills, child needs, and the home environment. Another example is social emotional learning programs delivered in schools, where children are taught to regulate emotions, manage behaviors, and enhance relationships with peers. Investing in these and other programs with a strong evidence base, and assuring their faithful implementation in practice settings, can produce improvements on a range of mental health, academic, and social outcomes for children, extending into their lives as adults.
Article
Marc Suhrcke
While definitional and measurement problems pose a challenge, there is no doubt that disability affects a noticeable share of the population, the vast majority of whom live in low- and middle-income countries (LMICs). The still comparatively scarce empirical data and evidence suggests that disability is closely associated with poverty and other indicators of economic deprivation at both the country and—if with slightly greater nuance—at the individual/household level. There is also a growing body of evidence documenting the sizeable additional costs incurred by persons with disabilities (PwDs) as a direct or indirect consequence of their disability, underlining the increased risk of PwDs (and the households they are part of) falling under the absolute poverty line in any given LMIC.
Looking ahead, there remains considerable scope for more evidence on the causal nature of the link between disability and poverty, as well as on the (cost-)effectiveness of interventions and policies attempting to improve the well-being of PwDs.
Article
Michael Drummond, Rosanna Tarricone, and Aleksandra Torbica
There are a number of challenges in the economic evaluation of medical devices (MDs). They are typically less regulated than pharmaceuticals, and the clinical evidence requirements for market authorization are generally lower. There are also specific characteristics of MDs, such as the device–user interaction (learning curve), the incremental nature of innovation, the dynamic nature of pricing, and the broader organizational impact. Therefore, a number of initiatives need to be taken in order to facilitate the economic evaluation of MDs. First, the regulatory processes for MDs need to be strengthened and more closely aligned to the needs of economic evaluation. Second, the methods of economic evaluation need to be enhanced by improving the analysis of the available clinical data, establishing high-quality clinical registries, and better recognizing MDs’ specific characteristics. Third, the market entry and diffusion of MDs need to be better managed by understanding the key influences on MD diffusion and linking diffusion with cost-effectiveness evidence through the use of performance-based risk-sharing arrangements.
Article
Cristina Bellés-Obrero and Judit Vall Castelló
The impact of macroeconomic fluctuations on health and mortality rates has been a highly studied topic in the field of economics. Many studies, using fixed-effects models, find that mortality is procyclical in many countries, such as the United States, Germany, Spain, France, Pacific-Asian nations, Mexico, and Canada. On the other hand, a small number of studies find that mortality decreases during economic expansion. Differences in the social insurance systems and labor market institutions across countries may explain some of the disparities found in the literature. Studies examining the effects of more recent recessions are less conclusive, finding mortality to be less procyclical, or even countercyclical. This new finding could be explained by changes over time in the mechanisms behind the association between business cycle conditions and mortality.
A related strand of the literature has focused on understanding the effect of economic fluctuations on infant health at birth and/or child mortality. While infant mortality is found to be procyclical in countries like the United States and Spain, the opposite is found in developing countries.
Even though the association between business cycle conditions and mortality has been extensively documented, a much stronger effort is needed to understand the mechanisms behind the relationship between business cycle conditions and health. Many studies have examined the association between macroeconomic fluctuations and smoking, drinking, weight disorders, eating habits, and physical activity, although results are rather mixed. The only well-established finding is that mental health deteriorates during economic slowdowns.
An important challenge is the fact that the comparison of the main results across studies proves to be complicated due to the variety of empirical methods and time spans used. Furthermore, estimates have been found to be sensitive to the use of different levels of geographic aggregation, model specifications, and proxies of macroeconomic fluctuations.
Article
Gabriella Conti, Giacomo Mason, and Stavros Poupakis
Building on early animal studies, 20th-century researchers increasingly explored the fact that early events—ranging from conception to childhood—affect a child’s health trajectory in the long-term. By the 21st century, a wide body of research had emerged, incorporating the original fetal origins hypothesis into the developmental origins of health and disease. Evidence from Organization for Economic Cooperation and Development (OECD) countries suggests that health inequalities are strongly correlated with many dimensions of socioeconomic status, such as educational attainment, and that they tend to increase with age and carry stark intergenerational implications. Different economic theories have been developed to rationalize this evidence, with an overarching comprehensive framework still lacking. Existing models widely rely on human capital theory, which has given rise to separate dynamic models of adult and child health capital within a production function framework. A large body of empirical evidence has also found support for the developmental origins of inequalities in health. On the one hand, studies exploiting quasi-random exposure to adverse events have shown long-term physical and mental health impacts of exposure to early shocks, including pandemics or maternal illness, famine, malnutrition, stress, vitamin deficiencies, maltreatment, pollution, and economic recessions. On the other hand, studies from the 20th century have shown that early interventions of various content and delivery formats improve life course health. Further, given that the most socioeconomically disadvantaged groups show the greatest gains, such measures can potentially reduce health inequalities. However, studies of long-term impacts as well as the mechanisms via which shocks or policies affect health, and the dynamic interaction among them, are still lacking. Mapping the complexities of those early event dynamics is an important avenue for future research.
Article
Ijeoma Peace Edoka
Low- and middle-income countries (LMICs) bear a disproportionately high burden of diseases in comparison to high-income countries, partly due to inequalities in the distribution of resources for health. Recent increases in health spending in these countries demonstrate a commitment to tackling the high burden of disease. However, evidence on the extent to which increased spending on health translates to better population health outcomes has been inconclusive. Some studies have reported improvements in population health with an increase in health spending whereas others have either found no effect or very limited effect to justify increased financial allocations to health. Differences across studies may be explained by differences in approaches adopted in estimating returns to health spending in LMICs.
Article
Albert A. Okunade and Ahmad Reshad Osmani
Healthcare cost encompasses expenditures on the totality of scarce resources (implicit and explicit) given up (or allocated) to produce healthcare goods (e.g., drugs and medical devices) and services (e.g., hospital care and physician office services are major components). Healthcare cost accounting components (sources and uses of funds) tend to differ but can be similar enough across most of the world countries. The healthcare cost concept usually differs for consumers, politicians and health policy decision-makers, health insurers, employers, and the government. All else given, inefficient healthcare production implies higher economic cost and lower productivity of the resources deployed in the process. Healthcare productivity varies across health systems of the world countries, the production technologies used, regulatory instruments, and institutional settings. Healthcare production often involves some specific (e.g., drugs and medical devices, information and communication technologies) or general technology for diagnosing, treating, or curing diseases in order to improve or restore human health conditions.
In the last half century, the different healthcare systems of the world countries have undergone fundamental transformations in the structural designs, institutional regulations, and socio-economic and demographic dimensions. The nations have allocated a rising share of total economic resources or incomes (i.e., Gross National Product, or GDP) to the healthcare sector and are consequently enjoying substantial increases in population health status and life expectancies. There are complex and interacting linkages among escalating healthcare costs, longer life expectancies, technological progress (or “the march of science”), and sectoral productivities in the health services sectors of the advanced economies. Healthcare policy debates often concentrate on cost-containment strategies and search for improved efficient resource allocation and equitable distribution of the sector’s outputs. Consequently, this contribution is a broad review of the body of literature on technological progress, productivity, and cost: three important dimensions of the evolving modern healthcare systems. It provides a logical integration of three strands of work linking healthcare cost to technology and research evidence on sectoral productivity measurements. Finally, some important aspects of the existing study limitations are noted to motivate new research directions for future investigations to explore in the growing health sector economies.
Article
Audrey Laporte and Brian S. Ferguson
One of the implications of the human capital literature of the 1960s was that a great many decisions individuals make that have consequences not just for the point in time when the decision is being made but also for the future can be thought of as involving investments in certain types of capital. In health economics, this led Michael Grossman to propose the concept of health capital, which refers not just to the individual’s illness status at any point in time, but to the more fundamental factors that affect the likelihood that she will be ill at any point in her life and also affect her life expectancy at each age. In Grossman’s model, an individual purchased health-related commodities that act through a health production function to improve her health. These commodities could be medical care, which could be seen as repair expenditures, or factors such as diet and exercise, which could be seen as ongoing additions to her health—the counterparts of adding savings to her financial capital on a regular basis. The individual was assumed to make decisions about her level of consumption of these commodities as part of an intertemporal utility-maximizing process that incorporated, through a budget constraint, the need to make tradeoffs between health-related goods and goods that had no health consequences. Pauline Ippolito showed that the same analytical techniques could be used to consider goods that were bad for health in the long run—bad diet and smoking, for example—still within the context of lifetime utility maximization. This raised the possibility that an individual might rationally take actions that were bad for her health in the long run. The logical extension of considering smoking as bad was adding recognition that smoking and other bad health habits were addictive. The notion of addictive commodities was already present in the literature on consumer behavior, but the consensus in that literature was that it was extremely difficult, if not impossible, to distinguish between a rational addict and a completely myopic consumer of addictive goods. Gary Becker and Kevin Murphy proposed an alternative approach to modeling a forward-looking, utility-maximizing consumer’s consumption of addictive commodities, based on the argument that an individual’s degree of addiction could be modeled as addiction capital, and which could be used to tackle the empirical problems that the consumer expenditure literature had experienced. That model has become the most widely used framework for empirical research by economists into the consumption of addictive goods, and, while the concept of rationality in addiction remains controversial, the Becker-Murphy framework also provides a basis for testing various alternative models of the consumption of addictive commodities, most notably those based on versions of time-inconsistent intertemporal decision making.
Article
Syed Abdul Hamid
Health microinsurance (HMI) has been used around the globe since the early 1990s for financial risk protection against health shocks in poverty-stricken rural populations in low-income countries. However, there is much debate in the literature on its impact on financial risk protection. There is also no clear answer to the critical policy question about whether HMI is a viable route to provide healthcare to the people of the informal economy, especially in the rural areas. Findings show that HMI schemes are concentrated widely in the low-income countries, especially in South Asia (about 43%) and East Africa (about 25.4%). India accounts for 30% of HMI schemes. Bangladesh and Kenya also possess a good number of schemes. There is some evidence that HMI increases access to healthcare or utilization of healthcare. One set of the literature shows that HMI provides financial protection against the costs of illness to its enrollees by reducing out-of-pocket payments and/or catastrophic spending. On the contrary, a large body of literature with strong methodological rigor shows that HMI fails to provide financial protection against health shocks to its clients. Some of the studies in the latter group rather find that HMI contributes to the decline of financial risk protection. These findings seem to be logical as there is a high copayment and a lack of continuum of care in most cases. The findings also show that scale and dependence on subsidy are the major concerns. Low enrollment and low renewal are common concerns of the voluntary HMI schemes in South Asian countries. In addition, the declining trend of donor subsidies makes the HMI schemes supported by external donors more vulnerable. These challenges and constraints restrict the scale and profitability of HMI initiatives, especially those that are voluntary. Consequently, the existing organizations may cease HMI activities.
Overall, although HMI can increase access to healthcare, it fails to provide financial risk protection against health shocks. The existing HMI practices in South Asia, especially in the HMIs owned by nongovernmental organizations and microfinance institutions, are not a viable route to provide healthcare to the rural population of the informal economy. However, HMI schemes may play some supportive role in implementation of a nationalized scheme, if there is one. There is also concern about the institutional viability of the HMI organizations (e.g., ownership and management efficiency). Future research may address this issue.
Article
Jordan Everson and Melinda Beeuwkes Buntin
The potential for health information technology (HIT) to reshape the information-intensive healthcare industry has been recognized for decades. Nevertheless, the adoption and use of IT in healthcare has lagged behind other industries, motivating governments to take a role in supporting its use to achieve envisioned benefits. This dynamic has led to three major strands of research. Firstly, the relatively slow and uneven adoption of HIT, coupled with government programs intended to speed adoption, has raised the issue of who is adopting HIT, and the impact of public programs on rates of adoption and diffusion. Secondly, the realization of benefits from HIT appears to be occurring more slowly than its proponents had hoped, leading to an ongoing need to empirically measure the effect of its use on the quality and efficiency of healthcare as well as the contexts under which benefits are best realized. Thirdly, increases in the adoption and use of HIT have led to the potential for interoperable exchange of patient information and the dynamic use of that information to drive improvements in the healthcare delivery system; however, these applications require developing new approaches to overcoming barriers to collaboration between healthcare organizations and the HIT industry itself. Intertwined through each of these issues is the interaction between HIT as a tool for standardization and systemic change in the practice of healthcare, and healthcare professionals’ desire to preserve autonomy within the increasingly structured healthcare delivery system. Innovative approaches to improve the interactions between professionals, technology, and market forces are therefore necessary to capitalize on the promise of HIT and develop a continually learning health system.
Article
Hendrik Schmitz and Svenja Winkler
The terms information and risk aversion play central roles in healthcare economics. While risk aversion is among the main reasons for the existence of health insurance, information asymmetries between insured individual and insurance company potentially lead to moral hazard or adverse selection. This has implications for the optimal design of health insurance contracts, but whether there is indeed moral hazard or adverse selection is ultimately an empirical question. Recently, there was even a debate whether the opposite of adverse selection—advantageous selection—prevails. Private information on risk aversion might weigh out information asymmetries regarding risk type and lead to more insurance coverage of healthy individuals (instead of less insurance coverage in adverse selection).
Information and risk preferences are important not only in health insurance but more generally in health economics. For instance, they affect health behavior and, consequently, health outcomes. The degree of risk aversion, the ability to perceive risks, and the availability of information about risks partly explain why some individuals engage in unhealthy behavior while others refrain from smoking, drinking, or the like.
Information has several dimensions. Apart from information on one’s personal health status, risk preferences, or health risks, consumer information on provider quality or health insurance supply is central in the economics of healthcare. Even though healthcare systems are necessarily highly regulated throughout the world, all systems at least allow for some market elements. These typically include the possibility of consumer choice, for instance, regarding health insurance coverage or choice of medical provider. An important question is whether consumer choice elements work in the healthcare sector—that is, whether consumers actually make rational or optimal decisions—and whether more information can improve decision quality.
Article
Richard Smith and Johanna Hanefeld
Global trade—the movement of goods, services, people, and capital between countries—is at the center of modern globalization. Since the late 20th century trade has also become established as a critical determinant of public health. As the raison d’être of trade is to increase both wealth and the availability of goods and services, changing trade patterns will inevitably impact many of the known determinants of health, including employment, nutrition, environmental factors, social capital, and education. Trade will also impact the health sector itself, most clearly through direct trade in health-related goods and services (such as pharmaceuticals, health workers, foreign direct investment in health services, and mobile patients), but also more broadly in determining tax receipts and thus overall public expenditures. It is also the case that trade—especially rapid and widespread movement of people, animals, and goods—may facilitate the rapid and widespread spread of disease. Trade, and associated policies governing and responding to that trade, has thus become increasingly recognized as a critical driver of health issues.
The design of trade policies that reduce the potential health risks associated with freer trade while maximizing the positive impact of trade liberalization on the social determinants of health is still in its infancy. There remains a lack of sound empirical evidence demonstrating how trade liberalization links directly and indirectly to health. Even though the positive link between increased trade, poverty reduction, and economic growth is widely accepted, evidence regarding the impact of trade liberalization on the social determinants of health varies from one national context to another. Hence, adapting trade liberalization to national conditions is important in ensuring desired outcomes. Yet although evidence is necessary, it is not sufficient to ensure that health is more integrated in trade negotiations and decision-making. There is a substantive requirement for those with a health remit to engage in negotiation with those from other sectors and from other geographic locations.
Article
Joanna Coast and Manuela De Allegri
Qualitative methods are being used increasingly by health economists, but most health economists are not trained in these methods and may need to develop expertise in this area. This article discusses important issues of ontology, epistemology, and research design, before addressing the key issues of sampling, data collection, and data analysis in qualitative research. Understanding differences in the purpose of sampling between qualitative and quantitative methods is important for health economists, and the key notion of purposeful sampling is described. The section on data collection covers in-depth and semistructured interviews, focus-group discussions, and observation. Methods for data analysis are then discussed, with a particular focus on the use of inductive methods that are appropriate for economic purposes. Presentation and publication are briefly considered, before three areas that have seen substantial use of qualitative methods are explored: attribute development for discrete choice experiment, priority-setting research, and health financing initiatives.
Article
Peter Sivey and Yijuan Chen
Quality competition between alternative providers is an increasingly important topic in the health economics literature. This literature includes theoretical and empirical studies that have been developed in parallel to 21st-century policies to increase competition between doctors or hospitals. Theoretical studies have clarified how competitive markets can give healthcare providers the incentive to improve quality. Broadly speaking, if providers have an incentive to attract more patients and patients value quality, providers will raise quality until the costs of raising quality are equal to the additional revenue from patients attracted by the rise in quality. The theoretical literature has also investigated how institutional and policy parameters determine quality levels in equilibrium. Important parameters in models of quality competition include the degree of horizontal differentiation, the level of information about provider quality, the costs of switching between providers, and the time-horizon of quality investment decisions.
Empirical studies have focused on the prerequisites of quality competition (e.g., do patients choose higher quality providers?) and the impact of pro-competition policies on quality levels. The most influential studies have used modern econometric approaches, including difference-in differences and instrumental variables, to identify plausibly causal effects. The evidence suggests that in most contexts, quality is a determinant of patient choice of provider, especially after greater patient choice is made available or information is published about provider quality.
The evidence that increases in competition improve quality in healthcare is less clear cut. Perhaps reflecting the economic theory of quality competition, showing that different parameter combinations or assumptions can produce different outcomes, empirical results are also mixed. While a series of high-quality studies in the United Kingdom appear to show strong improvements in quality in more competitive areas following pro-competition reforms introducing more choice and competition, other studies showed that these quality improvements do not extend to all types of healthcare or alternative measures of quality.
The most promising areas for future research include investigating the “black box” of quality improvement under competition, and behavioral studies investigating financial and nonfinancial motivations for quality improvements in competitive markets.
Article
Fabrizio Mazzonna and Franco Peracchi
Population aging, the combined effect of declining fertility and rising life expectancy, is one of the fundamental trends observed in developed counties and, increasingly, in developing countries as well. A key aspect of the aging process is the decline of cognitive ability. Cognitive aging is an important and complex phenomenon, and its risk factors and economic consequences are still not well understood. For instance, the relationship between cognitive aging and productivity matters for long-term economic growth. Cognitive functioning is also crucial for decision-making because it influences individuals’ ability to process information and to make the right choices, and older individuals are increasingly required to make complex financial, health, and long-term-care decisions that might affect their health, resources, and welfare. This article presents evidence from economics and other fields that have investigated this phenomenon from different perspectives.
A common empirical finding is the hump-shaped profile of cognitive performance over the life cycle. Another is the large variability of observed age profiles, not only at the individual level but also across sociodemographic groups and countries. The age profiles of cognitive performance also vary depending on the cognitive task considered, reflecting the different combinations of cognitive skills that they require. The literature usually distinguishes between two main types of cognitive skills: fluid intelligence and crystallized intelligence. The first consists of the basic mechanisms of processing new information, while the second reflects acquired knowledge. Unlike fluid intelligence, which declines rapidly as people get older, crystallized intelligence tends to be maintained at older ages. Differences in the age profiles of cognitive performance across tasks partly reflect differences in the importance of these two types of intelligence. For instance, tasks where learning, problem-solving, and processing speed are essential tend to be associated with a faster decline, while tasks where experience matters more tend to be associated with a slower decline. Various life events and behaviors over the life cycle also contribute to the large heterogeneity in the observed age profiles of cognitive performance. This source of variation includes not only early-life events and investments (e.g., formal education), but also midlife and later-life events (e.g., health shocks) and individual choices (e.g., health behaviors or retirement).
From an economic viewpoint, cognitive abilities may be regarded as one dimension of human capital, along with education, health, and noncognitive abilities. Economists have mainly focused their attention on human capital accumulation, and much less so on human capital deterioration. One explanation is that early-life investments appears to be more profitable than investments later in life. However, recent evidence from neuropsychology suggests that the human brain is malleable and open to enhancement even later in adulthood. Therefore, more economic research is needed to study how human capital depreciates over the life cycle and whether cognitive decline can be controlled.
