Improvements in Health

This section briefly documents the magnitude of health improvements and then points to the challenges that remain. For the past 160 years, life expectancy in the healthiest countries has increased steadily. At the same time, differences in life expectancy between those countries and much of the rest of the world have narrowed. Figure 1.1 depicts trends in female life expectancy in the country with the highest estimated level of life expectancy. From about 1600 to about 1840, there is fluctuation but no clear trend; after 1840, the graph turns upward at a surprisingly uniform rate of improvement: maximum life expectancy increased by about two and one-half years per decade for 160 years.

Figure 1.1

Trends in Maximum Female Life Expectancy, 1600–2000

Table 1.1 shows progress in life expectancy by World Bank region between 1960 and 2002. (Map 1 on the inside front cover depicts the World Bank regions.) For the first three decades of this period, progress was remarkably fast—a gain of 6.3 years in life expectancy per decade on average, albeit with substantial regional variation. Progress continued between 1990 and 2002 in the low- and middle-income countries but at a much slower pace. This slower pace is due, in great part, to mortality increases from HIV/AIDS. Sub-Saharan Africa actually lost more than four years of life expectancy.

Table 1.1

Levels and Changes in Life Expectancy, 1960–2002, by World Bank Region.

Since 1950, life expectancy in the median country has steadily converged toward the maximum and cross-country differences have decreased markedly. This reduction in inequality in health contrasts with long-term increases in income inequality between and within countries. Despite the magnitude of global improvements, many countries and populations have failed to share in the overall gains or have even fallen behind. Some countries—for example, Sierra Leone—remain far behind (figure 1.1). China's interior provinces lag behind the more advantaged coastal regions. Indigenous people everywhere probably lead far less healthy lives than do others in their respective countries, although confirmatory data are scant.

Reasons for remaining health inequalities lie only partially in income inequality: the experiences of China, Costa Rica, Cuba, Sri Lanka, and Kerala state in India, among many others, conclusively show that dramatic improvements in health can occur without high or rapidly growing incomes. The experiences of countries in Europe in the late 19th and early 20th centuries similarly show that health conditions can improve without prior or concomitant increases in income (Easterlin 1996). A recent review, undertaken in part as background for this volume, identified many specific examples of low-cost interventions leading to large and carefully documented health improvements (Levine and others 2004). The public sector initiated and financed virtually all of these interventions. The goal of this book is to assist decision makers—particularly those in the public sector—to realize the potential for low-cost intervention to rapidly improve the health and welfare of their populations.

Remaining Challenges

Four central challenges for health policy ensue from the pace and unevenness of the progress just documented and from the evolving nature of microbial threats to human health.

Epidemiological Transition

First, the next two decades will see continuation of trends resulting from the dramatic mortality declines of recent decades. The key phenomenon is that the major noncommunicable diseases—circulatory system diseases, cancers, and major psychiatric disorders—are fast replacing (or adding to) the traditional scourges—particularly infectious diseases and undernutrition in children. This phenomenon results in substantial part from rapid relative population growth at the older ages, when noncommunicable diseases become manifest. Additionally, injuries resulting from road traffic are replacing more traditional forms of injury. Using data from Chile, figure 1.2 illustrates the huge increase in the relative importance of injuries, cancers, and cardiovascular disease between 1909 and 1999. Responding to this epidemiological transition with sharply constrained resources is a key challenge. Tables 1.A1 and 1.A2 (see annex 1.A) provide cause-specific summaries of death and disease burden, measured in DALYs, in 2001 for the world as a whole and for low- and middle-income countries as a group as well as for high-income countries. Those summaries indicate that noncommunicable disease already accounts for over half of all deaths in the low-and middle-income countries, although nearly 40 percent of deaths continue to be from infection, undernutrition, and maternal conditions, creating a "dual burden" that Julio Frenk and colleagues have pointed to (Bobadilla and others 1993).

Figure 1.2

Distribution of Deaths by Cause in Chile, 1909 and 1999

Table 1.A1

Causes of Deaths in Low- and Middle-Income and High-Income Countries and the World, 2001 (percent).

Table 1.A2

The Burden of Disease in Low- and Middle-Income and High-Income Countries and the World, 2001 (percent).

Health and Income

How does health influence GDP per person? Healthy workers are more productive than workers who are similar but not healthy. Supporting evidence for this plausible observation comes from studies that link investments in health and nutrition of the young to adult wages (Strauss and Thomas 1998). Better health also raises per capita income through a number of other channels. One involves altering decisions about expenditures and savings over the life cycle. The idea of planning for retirement occurs only when mortality rates become low enough for retirement to be a realistic prospect. Rising longevity in developing countries has opened a new incentive for the current generation to save—an incentive that can dramatically affect national saving rates. Although this saving boom lasts for only one generation and is offset by the needs of the elderly after population aging occurs, it can substantially boost investment and economic growth rates while it lasts.

Encouraging foreign direct investment is another channel: investors shun environments in which the labor force suffers a heavy disease burden. Endemic diseases can also deny humans access to land or other natural resources, as occurred in much of West Africa before the successful control of river blindness.

Boosting education is yet another channel. Healthier children attend school and learn more while they are there. A longer life span increases the returns on investment in education.

Demographic channels also play an important role. Lower infant mortality initially creates a "baby-boom" cohort and leads to a subsequent reduction in the birth rates as families choose to have fewer children in the new low-mortality regime. A baby-boom cohort thereby affects the economy profoundly as its members enter the educational system, find employment, save for retirement, and finally leave the labor market. The cohorts before and after a baby boom are much smaller; hence, for a substantial transition period, this cohort creates a large labor force relative to overall population size and the potential for accelerated economic growth (Bloom, Canning, and Malaney 2000).

If better health improves the productive potential of individuals, good health should accompany higher levels of national income in the long run. Countries that have high levels of health but low levels of income tend to experience relatively faster economic growth as their income adjusts. How big an overall contribution does better health make to economic growth? Evidence from cross-country growth regressions suggests the contribution is consistently substantial. Indeed, the initial health of a population has been identified as one of the most robust and potent drivers of economic growth—among such well-established influences as the initial level of income per capita, geographic location, institutional environment, economic policy, initial level of education, and investments in education. Bloom, Canning, and Sevilla (2004) found that one extra year of life expectancy raises GDP per person by about 4 percent in the long run. Jamison, Lau, and Wang (2005) estimated that reductions in adult mortality explain 10 to 15 percent of the economic growth that occurred from 1960 to 1990. Not all countries benefit equally from this link. Bhargava and others (2001) found that better health matters more for income growth in low-income countries than in high-income ones. Although attribution of causality is never unequivocal in analyses like these, different types of evidence point consistently to a likely causal effect of health on growth.

Health declines can precipitate downward spirals, setting off impoverishment and further ill health. For example, the effect of HIV/AIDS on per capita GDP could prove devastating in the long run. An enormous waste of human capital occurs as prime-age workers die. A high-mortality environment deters the next generation from investing in education and creating human capital. The creation of a generation of orphans means that children may be forced to work to survive and may not get the education they need. High rates of mortality may reduce investment. Saving rates are likely to fall, and retirement becomes less likely. A foreign company is less likely to invest in a country with a high HIV prevalence rate because of the threat to the firm's own workers, the prospect of high labor turnover, and the loss of workers who have gained specific skills by working for the firm. The International Monetary Fund recently published a collection of important studies of the multiple mechanisms through which a major AIDS epidemic can be expected to affect national economies (Haacker 2004).

Health and Economic Welfare

Judging countries' economic performance by GDP per person fails to differentiate between situations in which health conditions differ: a country whose citizens enjoy long and healthy lives clearly outperforms another with the same GDP per person but whose citizens suffer much illness and die sooner. Individual willingness to forgo income to work in safer environments and social willingness to pay for health-enhancing safety and environmental regulations provide measures, albeit approximate, of the value of differences in mortality rates. Many such willingness-to-pay studies have been undertaken in recent decades, and their results are typically summarized as the value of a statistical life (VSL). Chapter 7 discusses these issues in the context of assessing the economic returns to investments in health research and development.

Although the national income and product accounts include the value of inputs into health care (such as drugs and physician time), standard procedures do not incorporate information on the value of changes in longevity. In a seminal paper, Usher (1973) first brought the value of mortality reduction into national income accounting. He did this by generating estimates of the growth in what Becker, Philipson, and Soares (2003) have called full income—a concept that captures the value of changes in life expectancy by including them in an assessment of economic welfare. Estimates of changes in full income are typically generated by adding the value of changes in annual mortality rates (calculated using VSL figures) to changes in annual GDP per person. These estimates of change in full income are conservative in that they incorporate only the value of mortality changes and do not account for the total value of changes in health status. Valuation of changes in mortality, it should be noted, is only one element—albeit a quantitatively important one—of potentially feasible additions to national account to deal with nonmarket outcomes. The U.S. National Academy of Sciences has recently proposed broad changes for the United States that would include but go beyond valuation of mortality change (Abraham and Mackie 2005).

For many years, little further work was done on the effects of mortality change on full income although, as Viscusi and Aldy (2003) document, the number of carefully constructed estimates of VSLs increased enormously. Bourguignon and Morrisson (2002) address the long-term evolution of inequality among world citizens, starting from the premise that a "comprehensive definition of economic well-being would consider individuals over their lifetime." Their conclusion is that rapid increases in life expectancy in poorer countries had resulted in declines in inequality (broadly defined) beginning sometime after 1950, even though income inequality had continued to rise. In another important paper, Nordhaus (2003) assessed the growth of full income per capita in the United States in the 20th century. He concludes that more than half of the growth in full income in the first half of the century—and less than half in the second half of the century—had resulted from mortality decline. In this period, real income in the United States increased sixfold and life expectancy increased by more than 25 years.

Three lines of more recent work extend those methods to the interpretation of the economic performance of developing countries. All reach conclusions that differ substantially from analyses based on GDP alone. Two of those studies—one undertaken for the Commission on Macroeconomics and Health (CMH) of the World Health Organization (WHO) (Jamison, Sachs, and Wang 2001) and the other at the International Monetary Fund (Crafts and Haacker 2004)—assessed the impact of the AIDS epidemic on full income. Both studies conclude that the AIDS epidemic in the 1990s had far more adverse economic consequences than previous estimates of effects on per person GDP growth would suggest. Accounting for mortality decline in Africa before the 1990s, on the other hand leads to estimates of much more favorable overall economic performance than does the trend in GDP per person. Figure 1.3 shows that in Kenya, for example, full income grew more rapidly in GDP per person before 1990 (and far more rapidly in the 1960s). After 1990 the mounting death toll from AIDS appears to have only a modest effect on GDP per person but a dramatically adverse impact on changes in full income. Becker, Philipson, and Soares (2003) extended the earlier work of Bourguignon and Morrisson (2002) in finding strong absolute convergence in full income across countries over time, in contrast to the standard finding of continued divergence (increased inequality) of GDP per person. Finally, Jamison, Jamison, and Sachs (2003) have adapted standard cross-country growth regressions to model determinants of full income (rather than GDP per person). Like Becker, Philipson, and Soares (2003), they conclude that inequalities have been decreasing.

Figure 1.3

Changes in GDP and Full Income in Kenya, 1960–2000

The dramatic mortality declines of the past 150 years—and their reversal in Africa by AIDS subsequent to 1990—have had major economic consequences. The effect of health on GDP is substantial. The intrinsic value of mortality changes—measured in terms of VSL—is even more substantial. What are the implications of these findings for development strategy and for benefit-cost analyses of public sector investment options? Using full income in benefit-cost analyses of investments in health (and in health-related sectors such as education, water supply and sanitation, and targeted food transfers) would markedly increase estimates of net benefits or rates of return. A careful, quantitative reassessment of competing policies for improving a country's living standards would probably conclude that development assistance and budgetary allocations to health deserve greater relative priority.

Under-Five Health Problems and Intervention Priorities

MDG-4 for under-five mortality (reducing its level in 2015 by two-thirds relative to what it was in 1990) is highly ambitious. Yet its implication of an average 4.3 percent per year decline is well within recent experience. In the first half of the MDG period (1990–2002), 46 countries achieved rates of decline in under-five mortality greater than 4.3 percent per year. Figure 1.4 displays trends in the rate of decline in under-five mortality relative to the requisite 4.3 percent per year for China, India, Latin America and the Caribbean, and Sub-Saharan Africa. Africa's slowed progress probably stems mostly from HIV/AIDS and the spread of resistance to previously effective and widely used antimalarial drugs. Map 2 (on the inside back cover of this book) shows country-specific progress in reducing under-five mortality:

Figure 1.4

Rate of Progress in Reducing Under-Five Mortality, 1960–2000: China, India, Latin America and the Caribbean, and Sub-Saharan Africa

• Countries colored in green experienced annual rates of decline greater than 4.3 percent in the first half of the MDG period (1990–2002).
• Countries colored in red saw no decrease (or an increase) in their under-five mortality.
• Countries colored in yellow and orange depict countries in between—with yellow indicating performance in the top half of the range between 0 and 4.3 percent, and orange indicating poorer performance in the bottom half of the range.

Basic knowledge about the cost-effectiveness of interventions to address maternal and child health has been available from the 1980s. DCP2's work provides a reassessment with few surprises but some additions. It makes two important relatively new points. The first results from noting that half of under-five deaths occur at ages less than 28 days, when the substantial but usually neglected problem of stillbirth is considered. DCP2 identifies some highly cost-effective approaches to intervention against stillbirth and neonatal death (chapter 27). The second new point results from the rapid spread of resistance of the malaria parasite to chloroquine and sulfadoxine-pyrimethamine (SP). These inexpensive, highly effective, widely available drugs provided an important partial check on the high levels of malaria mortality in Africa. Their loss is leading to an even greater rise in malaria mortality and morbidity that could be substantial. Figure 1.5 illustrates increases in malaria death rates in under-five children in Sub-Saharan Africa in the period from 1990 to 2001. The design of instruments for financing a rapid transition to effective new treatments—artemisinin combination therapies (ACTs)—is a high priority (chapter 21; Arrow, Gelband, and Jamison 2005).

Figure 1.5

Under-Five Deaths from AIDS, Malaria, and Other Causes, per Thousand Births, 1990 and 2001, Sub-Saharan Africa

The other intervention priorities for addressing under-five mortality are for the most part familiar:

• Expand immunization coverage.
• Expand the use of the simple and low cost but highly effective treatments for diarrhea and child pneumonia through integrated management of childhood illness or other mechanisms.
• Prevent transmission of and mortality from malaria by expanding coverage of insecticide-treated bednets, by expanding use of intermittent preventive treatment for pregnant women, and, particularly, by financing the adoption of ACTs to replace the now widely ineffective drugs chloroquine and SP.
• Ensure widespread distribution of key micronutrients.
• Expand the use of a package of measures to prevent mother-to-child transmission of HIV (further discussed in the next section on HIV/AIDS).

In addition to interventions to reduce under-five mortality, one other priority is clear. The world's most prevalent infections are intestinal helminth (worm) infections, and children of all ages are among the most heavily affected. Chapter 24 discusses these infections, which a low-cost drug (albendazole), taken every six months to a year, can control effectively. Chapter 58 on school health services points to both the importance to children's school progress of taking albendazole where needed and the potential efficacy of school health programs as a vehicle for delivery. In the long run, improved sanitation and water supplies will prevent transmission. Use of albendazole is only an interim solution, but it is one that may be required for decades if the experience of the currently high-income countries is relevant.

Delivering Child Health Interventions

The list of potential interventions is far from exhaustive, and different regions, countries, and communities will face different mixes of the problems these interventions address. However, there can be little dispute that any short list of intervention priorities for under-five mortality in low- and middle-income countries would include many on the list in the preceding section. Why not, then, simply put money into scaling up these known interventions to a satisfactory level?

To greatly oversimplify—and these issues are discussed more substantially in chapter 3—two schools of thought exist. One line of thinking—often ascribed to macroeconomist Jeffrey Sachs and his work as chair of the WHO CMH—concludes that more money and focused effort are the solutions. Although acknowledging dual constraints—of money and of health system capacity—Sachs and his colleagues (WHO CMH 2001; Sachs 2005) contend that money can buy (or develop, or both) relevant system capacity even over a period as short as five years. Major gains are affordable and health system capacity constraints can be overcome. Immunization provides an example of where, even in the short term, money can substitute for system capacity. Adding antigens for Haemophilus influenzae type B (Hib) and hepatitis B (HepB) to the immunization schedule is costly (although still cost-effective). In some environments, however, it proves less demanding of system capacity than expanding coverage does. Money can be effectively spent by adding antigens at the same time as investing in the capacity to extend coverage.

A second school of thought acknowledges the need for more money but asserts that health system capacity is often a binding short- to medium-term constraint on substantial scaling up of interventions. Critical priorities are, therefore, system reform and strengthening while ensuring that such reforms focus clearly on achieving improved health outcomes and financial protection.

Chapter 3, as indicated, discusses these issues further in the context of all the problems facing a health system, and chapter 9 provides a thoughtful assessment of how to overcome the constraints facing achievement of the MDGs for health. From an individual country's perspective, however, if financial resources are available, the question is very much an empirical one: to what extent can those resources be effectively deployed in buying interventions, in buying out of prevailing system constraints, and in investing in relevant system capacity for the future? What needs to be constantly borne in mind throughout this continued controversy is that something works: under-five mortality rates have plunged by more than half since 1960 in the low- and middle-income countries.

Tools to Control the Epidemic

In contrast to the initially slow programmatic movement of most national leaders and international institutions, the research and development community—public and private—has made rapid progress in developing tools to control the HIV/AIDS epidemic, although both a vaccine and a curative drug remain distant objectives. Sensitive, specific, and inexpensive diagnostics are available; means of prevention have been developed and tested; modes of transmission are well understood; and increasingly powerful drugs for controlling viral load allow radical slowing of disease progression. Tools for dealing with HIV/AIDS are thus available: As emphasized in chapter 18, a number of countries show by example that those tools can be put to effective use. Most of the high-income countries have done so, and Brazil and Mexico provide examples of upper-middle-income countries that have forestalled potentially serious epidemics. Mexico succeeded, for example, with a policy of responding both early and forcefully to the epidemic (del Rio and Sepúlveda 2002). The major successes of Thailand and Uganda demonstrate that countries with fewer financial resources can also succeed—and succeed against more established epidemics that had already penetrated deeply into their populations.

Prevention and Management

Prevention underpins success. At the time the World Bank's World Development Report: Investing in Health (World Bank 1993) was being written in 1992 and 1993, the only tool for dealing with the epidemic was prevention. In collaboration with the then–Global Programme against AIDS at WHO, the World Development Report commissioned very approximate estimates of the consequence for the new infection rate of fully implementing available preventive measures (its optimistic case scenario) or of doing very little (worst case). Actual incidence numbers for 2000, unfortunately, fall very close to the worst-case projection, and chapter 18 points out that even by 2003 fewer than one in five people at high risk of infection had access to the most basic preventive services. In much of the world, little has been spent on prevention, and little has been achieved. In addition, the current U.S. administration may be partially responsible for discouraging condom use in some countries and in stigmatizing and alienating commercial sex workers who are particular priorities for prevention programs. Despite those problems, the potential for prevention is very real, and a number of successful countries have shown the possibility of using that potential well. Chapter 17 on sexually transmitted infections (STIs) and chapter 18 on AIDS discuss a broad menu of preventive measures and experiences with their implementation. Among them, treatment of STIs may be of particular salience both because the diseases are well worth treating in their own right and because the absence of STIs greatly reduces transmission of HIV.

In addition to prevention, better management of patients with AIDS could avert much misery, both by treating opportunistic infections and by ameliorating the often excruciating pain associated with many AIDS deaths. Medically inappropriate restrictions on the use of inexpensive but powerful opiates for pain control continue to deny dignity and comfort to millions of patients with AIDS and cancer in their final days (chapter 52).

Antiretroviral Treatment

Intensive research and development efforts have led in the past decade to the availability of well over a dozen antiretroviral drugs that can greatly reduce the quantity of HIV in an infected person. This reduction in viral load slows or halts progression of AIDS and can return individuals from serious illness to reasonable health. Available drugs leave a residual population of HIV in the body, however, and this population grows if the drugs are stopped. At present the drugs must be taken for life. Widespread use of these drugs in high-income (and some middle-income) countries has transformed the life prospects of HIV-infected individuals.

Early generation antiretroviral drugs suffered notable shortcomings: they were enormously costly; regimens for their use were complicated, making adherence difficult; their use generated unpleasant side effects; and rapid evolution of HIV led to resistant mutants that undermined the efficacy of therapy. In a remarkably short time, scientific advances have substantially attenuated those problems, making feasible, at least in principle, antiretroviral therapy in low-income settings. WHO's "3 by 5" program had as its objective, for example, to reach 3 million people in low- and middle-income countries with antiretroviral therapy by 2005. Although that goal was far from being met, the global effort to make treatment widely available is well under way.

Despite the indicated progress against the problems with antiretroviral drugs, challenges to their effective use in low-income environments remain formidable. The complexity of patient management is very real. Management requires high levels of human resources and other capacities in many of the countries where those capacities need to be most carefully rationed. Perhaps in consequence, achieving effective implementation has been difficult on even a limited scale. Chapter 18 reviews those problems and how they might be addressed.

Three points concerning widespread antiretroviral drug use are particularly noteworthy:

• Poor implementation (low adherence, development of resistance, interruptions in drug supplies) is likely to lead to very limited health gains, even for individuals on therapy. (This outcome is unlike that of a weak immunization program in which health gains still exist in the fraction of the population that is immunized.) Poorly implemented anti-retroviral drug delivery programs could divert substantial resources from prevention or from other high-payoff activities in the health sector. Even worse, they could lead to a false sense of complacency in affected populations: evidence from some countries suggests that treatment availability has led to riskier sexual behavior and increased HIV transmission. The injunction to "do no harm" holds particular salience.
• Unless systematic efforts are made to acquire hard knowledge about which approaches work and which do not, the likelihood exists that unsuccessful implementation efforts will be continued without the appropriate reallocation of resources to successful approaches. Learning what works will require major variations in approach and careful evaluation of effects. Failing to learn will lead to large numbers of needless deaths. Most efforts to scale up antiretroviral therapy unconscionably fail to commit the substantial resources required for evaluation of effects. Such evaluations are essential if ineffective programs are to be halted or effective ones are to receive more resources.
• Many programs rely exclusively on the cheapest possible drugs, thereby risking problems with toxicity, adherence, and drug resistance. From the outset a broader range of drug regimens needs to be tested.

Cardiovascular Disease

Cardiovascular diseases in low- and middle-income countries result in about 13 million deaths each year, over a quarter of all deaths in those countries. Most cardiovascular deaths result from ischemic heart disease (5.7 million) or cerebrovascular disease (4.6 million). Because such deaths occur at older ages, they account for a substantially smaller fraction of total disease burden in disability-adjusted life years (DALYs)—12.9 percent—than they do of deaths (table 1.A2).

Growing tobacco use accounts for a substantial and avoidable fraction of CVD and of cancers. Reasonable projections show the number of tobacco-related deaths to be not only large but also growing, particularly in developing countries. In 2000, the number of tobacco-related deaths in developing countries about equaled the number in high-income countries; projections suggest that by 2030 developing countries will have more than twice as many. For those reasons, controlling smoking is a key element of any national strategy for preventing CVD or for promoting health more generally. Preventing the initiation of smoking is important because addiction to tobacco makes smoking cessation very difficult, even for the numerous individuals who would like to do so. However, helping people quit smoking is at least as important as preventing initiation. Figure 1.6 portrays estimates showing that far more lives could be saved between now and 2050 with successful efforts to help people stop smoking than with efforts to keep them from starting. Reducing smoking levels is well demonstrated to be within the control of public policy. The principal instrument is through taxation: Complementary measures discussed in chapter 46 are important as well.

Figure 1.6

Increase in Tobacco-related Deaths as Populations Age

The main risk factors for CVD account for very large fractions of the deaths (and even more of the burden) from those diseases. For ischemic heart disease, they collectively account for 78 percent of deaths in low- and middle-income countries; for stroke, they account for 61 percent (Ezzati and others 2006). Measures to reduce the levels of those risk factors—high blood pressure, high cholesterol, smoking, obesity, excessive alcohol use, physical inactivity, and low fruit and vegetable consumption—are the goals for prevention. Unlike the favorable experience with controlling tobacco use, attempts to change the behaviors leading to obesity, hypertension, high cholesterol, or physical activity appear to have had little success at a population level. However, as chapter 44 documents, many promising approaches remain to be tried. Common sense suggests that they should be initiated even while more systematic efforts to develop and evaluate behavior-change packages are ramped up.

Pharmaceutical interventions to manage two major components of cardiovascular risk—hypertension and high cholesterol levels—are well established and are highly cost-effective for individuals at high risk of a stroke or heart attack. From at least the time of publication of Disease Control Priorities in Developing Countries, 1st edition (DCP1), researchers have recognized that the low cost and high effectiveness of drugs to prevent the reoccurrence of a cardiovascular event made their long-term use potentially cost-effective in low-income environments (Pearson, Jamison, and Trejo-Gutierrez 1993). Even if sustained behavior change proves difficult to achieve, medications have the potential to reduce CVD risks by 50 percent or more. Chapters 33 and 45 develop the current evidence on that point. A key problem, however, concerns the health care personnel and systems requirements associated with the need for lifelong medication use, a problem also faced with antiretroviral therapy for AIDS and the use of medications to target several major psychiatric disorders. How to achieve effective long-term management of lifesaving drugs is a key delivery and research challenge for health system reformers.

In contrast to the lifelong requirement for drug use associated with CVD risk reduction in high-risk individuals, treatment of acute heart attacks with inexpensive drugs is both less demanding of system resources and highly cost-effective (chapter 45). Given the high incidence of these problems, systemwide efforts to achieve high rates of appropriate drug use in response to acute heart disease are a high priority.

Psychiatric Disorders

Although neurological and psychiatric disorders lead to only about 1.4 percent of deaths in low- and middle-income countries (1.8 percent in high-income countries), they cause suffering and disability far beyond what the mortality numbers suggest. About 10 percent of disease burden in DALYs in low- and middle-income countries results from these conditions; three major psychiatric diseases—unipolar major depression (3.1 percent of DALYs), bipolar disorder (0.6 percent), and schizophrenia (0.8 percent)—account for much of it (table 1.A2).

Chapter 31 provides a concise overview of advances made in recent years in treating these conditions (as well as panic disorder), summarizes information on their burden, and develops estimates of the cost-effectiveness of drug-based and cognitive behavioral therapies in different settings (hospital based and community based). Although the cost-effectiveness estimates reported in chapter 31 suggest interventions are only moderately cost-effective, the authors suggest that a fuller analysis of benefits than is captured by a health metric such as the DALY would justify substantial investments. They analyze a basic package of mental health services that could provide a practical vehicle for providing these interventions in environments with tightly constrained financial and implementation resources. A continuing theme in this volume—and one of particular relevance here—is that without careful evaluations of the effects of alternative approaches to large-scale intervention against psychiatric disorders, the world will fail to develop hard knowledge of what does—and does not—work. Without that knowledge, far less health and financial security will be gained than is potentially possible from the inevitably limited resources available.

Injuries

Injuries constitute an additional major and neglected component of disease burden in developing countries. This volume's chapters on injury (chapters 39 and 40) emphasize prevention. Timely treatment is also important, and chapters 67 (on surgery) and 68 (on emergency medical services) point to the potential, at low cost, for much better treatment of injury victims than is typical today.

The great diversity of both causes and consequences of injury precludes an attempt in this chapter to do more than highlight their importance. Chapter 2 and the injury-related chapters just mentioned provide a rich menu of practical options. It is worth pointing out here the central importance of two specific categories of injury—road-traffic injuries (1.07 million deaths in 2001 in low- and middle-income countries) and suicides (0.75 million deaths). Safer roads, safer driving, safer vehicles, and better emergency care have sharply reduced the toll from road-traffic injuries in high-income countries, but unless dramatic action is taken in developing countries, the toll will surely rise. Although there has been less success in reducing suicide rates, the improved treatments now available for psychiatric disorders are proving to be one important approach in suicide prevention.

This discussion of noncommunicable diseases and injury highlights the huge and growing burden from those conditions and conveys a consistent message that constructive action is feasible at relatively modest cost. No attempt has been made to be comprehensive (chapters 29 through 38 all deal with non-communicable diseases); rather the discussion points to the need for health systems to systematically incorporate effective responses to noncommunicable diseases and injuries as their capacities grow.

Health System Performance

Since about 1940, the publication of economic performance indicators in national income and product accounts has made it possible to hold political leaders accountable for economic management. Additionally, measures of economic performance—such as GDP growth rates and unemployment rates—have allowed economists to move toward evidence-based assessments of which policies facilitate good economic performance and which do not.

In many ways, unfortunately, the assessment of health system performance remains where economic performance measures were before the development of national income and product accounts in the United Kingdom in the late 1930s. Chapter 3 observes, for example, that "The body of knowledge [on health systems] represents a largely ad hoc and disjointed collection of facts, figures, and points of view. Making confident recommendations relevant to strengthening health system capacity is thus difficult." In its 2000 World Health Report, WHO made an ambitious effort to provide the performance measures for health systems that would enable progress toward more systematic knowledge of the policies to improve health systems (WHO 2000). Such knowledge could replace what is now frequently simply ideology and opinion. The 2000 World Health Report proved to be highly controversial, and its ranking of health system performance may in the end be judged as more of a first attempt than an initial approximation (Jamison and Sandbu 2001). WHO set an agenda that will certainly continue to be advanced.

Despite current inability to judge health system performance and the consequently ad hoc character of knowledge, much is in fact known that bears on health policy. Chapters 2 and 3 of this volume summarize very specific knowledge about intervention characteristics and system design that can inform policy. Although broad prescriptions may still elude us, particular knowledge is still important. Additionally, the performance of countries is better understood even though relating country performance to performance of its health systems may remain only judgmental for the moment. For example, Brazil and China had under-five mortality rates that were quite close in 2002: 37 per 1,000 for Brazil and 38 per 1,000 for China. In 1990, however, Brazil's rate was 60 per 1,000 and China's was 49 per 1,000: the rate of improvement in Brazil was far more rapid than in China. This measure is only one dimension of outcome, and many explanations are possible. Yet hard numbers on country perform do exist to initiate discussions of policy.

Financing Health Services

Chapters 12 and 13 in this volume discuss domestic and external financing of health systems. Different issues arise in low-income countries than in middle-income ones, and the discussion that follows is so divided. Table 1.2 provides context by conveying the level of health expenditures in 2001 in different income groupings of countries, the fraction of GDP spent on health, and the extent to which those expenditures are publicly financed. Almost 10 percent of the total product of the world pays for health services. In the low-income countries, about three-quarters of expenditures are from private, out-of-pocket payment. In the high-income European countries, only about one-quarter of expenditures is private. Middle-income countries spend about 5 times as much per capita on health services as do low-income ones and over 10 times as much through the public sector. Although available data sets (for example, from the World Bank or WHO) provide no direct evidence on trends over time in health expenditures (for more than very short periods), current levels of expenditure are likely to substantially exceed those of several decades ago, even as a percentage of growing incomes. The availability of physicians provides one indicator: in a large sample of countries the number of physicians per 100,000 population increased from 54 in the mid 1960s to 116 in the early 1990s, an annual rate of increase of 2.8 percent.

Table 1.2

Health Expenditures by Country Income Level, Public and Total, 2001.

Before we turn to questions of financing health services (or insurance), briefly discussing related issues concerning the public sector's financial role is worthwhile. Those issues address what chapter 11 calls "healthy fiscal policy and fiscal policy for health." An example of unhealthy fiscal policy was the Polish government's subsidy of fatty animal products. Elimination of that subsidy was a gain for the treasury and resulted in improved diets and health. Minimally, a healthy fiscal policy identifies and corrects such inappropriate subsidies. Fiscal policy for health is exemplified by tobacco taxation, which chapter 46 deals with at length and chapter 11 deals with more briefly. Fiscal policy for health involves taxes whose principal purposes lie more in changing health-related behaviors than in generating revenue (although the latter can be important as well).

Financing Health in Low-Income Countries

Approximately 2.5 billion people live in countries the World Bank classifies as low-income—that is, with a per capita gross national income in 2002 of less than US$735 per year. These countries include India but not China. Table 1.2 reflects that the estimated average per capita health expenditure for these 2.5 billion people is about US$23 per year, of which US$5 or US$6 comes from public sources. Chapter 12, on financing health systems, points to the severe challenges in setting priorities that these resource limitations imply. Not only are expenditure levels currently very low, but also the fiscal space needed to increase them is, in most low-income countries, sharply constrained. Fiscal space results from an excess of potential government revenues, including reasonable projections of official development assistance (ODA), over public expenditures. The concept of fiscal space combines both short-term fiscal balance and long-term debt sustainability. Grant ODA can help with short-term balance, and soft loans (such as International Development Association credits from the World Bank) can reduce the repayment burden from a given level of incurred debt. Health financing policy for low-income countries must focus heavily on mobilizing public sector resources and concentrating resources on true priorities (although the broader range of issues just discussed that middle-income countries must address is relevant to low-income countries with large formal sectors).

The chapters in this volume make clear that incremental resources for health, well spent, could have an enormous effect: resource mobilization is important. Increasing public sector expenditures in health by 0.5 percent or more of GDP will be possible in some countries, but not in all, and even where it is possible other investment priorities will also be pressing. However, increases of as much as 1 percent of GDP may possible where the political will exists, as is now being attempted in India. Cost estimates for meeting just the health-related MDGs, as reported in chapter 9, can exceed that amount, and other estimates have run higher. Development assistance for health, discussed in chapter 13 and here, can expand the available resource envelope, but even multiples of current levels of development assistance would likely prove insufficient to finance attainment of the MDGs in some countries.

Achieving gains for health (and frequently concomitant gains in financial protection) requires that critical decisions be made on how to allocate highly limited public sector resources. Much of this volume deals with resource allocation across interventions. Public finance must address an additional set of decisions. Do interventions with substantial positive externalities have a particular claim on public resources—beyond the amount of health and financial protection they buy per million dollars spent? Should public resources be spent only on individuals with low income? Or should health systems provide universal public finance for the very limited range of interventions that can be afforded? Should public finance emphasize providing interventions that maximize financial protection or improvements in health? What patterns of public sector resource allocation are likely to prove politically sustainable? Fewer tradeoffs may exist among these criteria than at first seems to be the case.

A starting point for thinking about these criteria is the availability of an increasing number of good benefit incidence studies—that is, studies of how the benefits of a public intervention distribute across income (or asset) quintiles of the population. Those studies find that in a great majority of countries wealthier people are more likely to benefit from public programs than are the poor, at least where benefits are measured in expenditures. The World Bank's 1993 World Development Report pointed to that pattern some time ago (although noting a number of important exceptions), and more recent studies add support to that conclusion. The caveat "measured in expenditures" is important and insufficiently noted. The value or welfare benefit to the poor of a given level of transfer may well exceed the value received by the well off from the same level of transfer. A landmark benefit incidence study of the U.S. Medicare program, a mandatory health insurance for the elderly, found it to be regressive in dollar terms but pro-poor in welfare outcomes (McClellan and Skinner 1997).

Public programs that are not universal appear to systematically benefit the better off, and that pattern is understandable from a political perspective. It follows that if an immunization program, for example, is differentially benefiting the well off, then making immunization universal would be pro-poor in terms of incremental public expenditures. Figure 1.7 uses data from a careful benefit incidence assessment in the Philippines (Gwatkin and others 2000) to illustrate this point for immunization and for attended deliveries.

Figure 1.7

Equity Implications of Providing Universal Coverage for Immunization and Attended Delivery in the Philippines, 1998

Making coverage universal for cost-effective interventions for conditions important to the poor is thus likely to prove to be an efficient way of both improving health outcomes and enhancing equity. Many of these interventions address infectious disease where control has significant externalities, and implementing universal coverage is likely to prove more politically sustainable than targeting population subgroups. Lindert (2004) extensively discusses the experience in high-income countries with universalization of public financing of education, health, and old-age pensions and concludes not only that it is politically sustainable but also that no evidence indicates that the resulting higher taxes have harmed economic growth.

Two final points are worth stating about making coverage universal:

• First, early adoption of universalization of coverage for publicly financed interventions—even if only a few can be financed—sets the stage for expansion, in a middle-income environment, to universal public financing of health care, the overwhelming choice of the democratic process in high-income countries.
• Second, the implementation capacity of health systems in low-income countries will often be highly constrained. Capacity is likely to grow most rapidly by building on a base of doing a few things well rather than many things poorly. Universal coverage implies tight focus in highly resource-constrained environments.

Aid Effectiveness

Recent work has been reassessing aid effectiveness and has focused on the following questions: Is there any evidence that infusions of development assistance have affected economic growth rates? Is there any evidence that infusions of economic assistance have affected mortality rates or levels of poverty? These questions are clearly not easy to answer. Nonetheless, some data provide insights. Burnside and Dollar (2000) conclude, for example, that development assistance does seem to work in countries where a good policy environment and a good institutional environment exist, but not in countries lacking those elements. Recent work focuses on aid directed to economic development and greatly strengthens the inclusiveness of the conclusion that aid boosts growth (Clemens, Radelet, and Bhavnani 2004). The effect of development assistance on growth is quantitatively important even in countries with poor policies and institutions, although the effect is stronger in countries with better policies. Interestingly, aid's effect appears larger in countries with higher life expectancy. That development assistance contributes broadly to growth does not, of course, imply that development assistance for health will accelerate health improvements. However, it is certainly suggestive of the potential in health to know that development assistance works for growth.

Even if development assistance is viewed as working better in strong institutional and policy environments, a dilemma exists in that the countries that most need aid are often ones that have weak policies and weak institutions (Radelet 2003, 194). Experiences with ODA in health complement the recent research on aid for growth in suggesting that ODA can pay off despite limited institutional or absorptive capacity. Polio has certainly been eliminated in countries with good health systems, but it has also been eliminated from most countries with weak ones. No smallpox exists today in countries with bad policies and bad institutions. A number of those countries have immunization rates of 60 or 70 percent, or as high as in the United States. An important question concerns the extent to which other development assistance for health, particularly highly targeted development assistance, can be as successfully implemented as immunization programs where health systems are weak.

Project Support versus Budget Support

Development assistance is tending to move away from project support—for example, of an immunization program, an AIDS control program, or an extension of a road network—and toward general budgetary support, often to be provided through pooling of donor assistance. There are many reasons for this tendency, some of which are good (Kanbur and Sandler 1999, 106). The usefulness (and even propriety) of budget support is contingent, however, on adequacy of the policy and institutional environments. Chapter 3 points to arguments that as health systems evolve, development assistance should move from project assistance toward program assistance. The Global Alliance for Vaccines and Immunization (GAVI) is pointing to ways that support for immunization programs can be advanced within the context of this tendency to move toward general budget support. GAVI's innovation is to support immunization programs based on performance—US$20 for a fully immunized child. The country gets the US$20 for immunizing the child in whatever way it decides; thus, GAVI provides general budget support that is conditioned on performance. GAVI's concern has been with transitional financing (rather than with sustained assistance), but its approach points the way for designing long-term budget support conditioned on measurable performance with respect to specific health goals. Jamison (2004) outlined design of long-term development assistance for health that could meet this objective, maintaining incentives for countries to increase coverage (or performance) while scaling back the volume of aid as a country's income increased. Adequate measurement underpins assessment of performance and can be difficult even for immunization coverage. Measurement requires resources that must be planned for and budgeted.

Macroeconomic Consequences of Aid

Another concern in the aid community—particularly in the International Monetary Fund—is that development assistance could have adverse domestic macroeconomic consequences—essentially inflationary consequences (see WHO 2002, chapter 8). This argument needs to be taken seriously. It is in essence an argument about the generation of domestic inflationary pressures—of projects chasing after those few good engineers or doctors with an increasing amount of foreign money and creating an inflationary spiral in that way. However, if the principal proposed use for the money is for drugs or vaccines—for example, the US$10 increment for adding Hib and HepB vaccines to the Expanded Program on Immunization schedule—that money is almost all foreign exchange, and the macroeconomic arguments about inflationary consequences simply would not apply. Careful project design can respond to what on the whole are serious concerns from the macroeconomic part of the development assistance community. Economic analysis can provide information—such as this volume attempts to provide—on getting the maximum health and financial protection outcomes from the development assistance available and for designing interventions (tradable and commodity intensive) that will minimize potentially adverse macroeconomic consequences.

The Millennium Development Goals

An additional and significant direction in thinking about ODA concerns achievement of the MDGs (chapter 9). The MDGs are very specific targets for improvement in education, health, and income-related poverty. Interestingly, focusing development assistance on achieving the MDGs stands in at least partial opposition to the move toward budget support.

These considerations point to several directions for the design of development assistance for health. Radelet (2003, 194) provides detailed quantitative examples to show that, even under very favorable circumstances, in a lower-middle-income country development assistance is likely to be needed for decades. Some conclusions follow that are drawn from the preceding discussion and from the need for predictability and long time horizons in donor behavior. ODA should move toward the following:

• providing aid over long-term perspectives (10 or more years)
• ensuring predictability in assistance commitments
• emphasizing demand-side support (with concomitant country control of resources)
• providing incentives for countries to maintain high coverage for cost-effective programs
• avoiding perverse incentives
• including a transparent exit strategy (for example, reduced grant support with per capita GDP growth).

There is a strong analogy to within-country programs like Mexico's Progresa, which provides cash transfers to poor households contingent on getting children immunized or into school. Gertler (2004) has reported evaluation results indicating a high degree of effectiveness. The effectiveness of coverage incentives is well exemplified by the Bill & Melinda Gates Foundation in its work on polio with both GAVI and the World Bank in providing a financial incentive for enhanced coverage (chapter 13). Although donors increasingly state a commitment to providing aid predictably and over long periods, the reality for many countries is that aid flows will be volatile and of uncertain duration. Jamison and Radelet (2005) point to ways of using such aid that can be minimally disruptive.

Interventions

1. Standard interventions for reducing under-five mortality have long been known to be highly cost-effective. The challenge is to scale up while conserving and strengthening scarce health system capacity. These interventions include immunization; micronutrient supplement delivery; treatment for diarrhea, malaria, and acute respiratory infections; and improved prenatal and delivery care. In cases of sharply limited resources—financial or health system capacity—often the single highest priority will be expansion of immunization coverage with the basic antigens: poliomyelitis, measles, diphtheria, tetanus, pertussis, and perhaps BCG.

2. Cost-effective interventions exist to address the 50 percent of under-five deaths that occur under 28 days of age, including stillbirths. These are underused relative to interventions for older children, and correcting this neglect is a priority.

3. Standard interventions to treat TB are also known to be highly cost-effective, although probably more demanding of health system capacity than are some of the child health interventions. Scaling up by using already developed models for strengthening relevant health system capacity is a priority.

4. Many well-tested preventive interventions for AIDS are effective and cost-effective. Such interventions include treating STIs, promoting condom use, providing voluntary counseling and testing, promoting peer intervention, using antiretroviral therapies to prevent mother-to-child transmission, ensuring safe blood supplies, and encouraging the use of breast milk alternatives by HIV-positive mothers. Scaling up treatment for STIs may prove particularly important. Much more rapid implementation of these interventions is of highest priority and needs to be accompanied by effective mechanisms of surveillance and evaluation. The appropriate mix and distribution of interventions depends on the stage of the epidemic. In particular, limited financial and institutional resources imply focusing effort on populations at high risk early in an epidemic.

5. Antiretroviral drugs have been successful on a wide scale in high-income countries (and in some upper-middle-income countries—notably Brazil and Mexico) in sharply reducing viral load and extending the life expectancy of patients who are HIV positive. Health system capacity for achieving durable benefits from antiretroviral drug use at scale in resource-constrained environments, however, remains to be demonstrated. Failure to achieve good adherence in such an environment would provide minimal benefits to the patient, increase risks of drug resistance, and incur substantial costs: the financial and human losses could be enormous. Multiple approaches to successful maintenance on antiretroviral drugs should be tried and evaluated in large-scale pilots or as part of implementation scale-up. Given the magnitude of the AIDS problem, undertaking and evaluating variations in implementation (including possible variation in the choice of first-line drugs) in parallel rather than serially is important. This approach is not now being used. Similarly important is being rigorous in dropping unsuccessful implementation models before they consume substantial resources that could otherwise have greatly affected AIDS prevention or other priorities in the health sector.

6. Control of tobacco use is the cornerstone of proven approaches to primary prevention of heart disease, stroke, chronic pulmonary disease, and many types of cancer. Instruments for control of tobacco use centering on taxation and improved public information are well established.

7. A range of potential approaches to changing dietary and exercise patterns of populations would, if successful, reduce problems of obesity, hypertension, and dyslipidemia and their consequences for vascular disease. Successes are rare but suggestive that large-scale efforts could be worthwhile. Careful impact evaluation will be essential to ascertain whether these investments deliver value for money.

8. Lifetime medical management—eventually using variants of the polypill—of individuals at high risk for stroke or ischemic heart disease is cost-effective and important for tens of millions of individuals. The clearest indications of high risk are a previous vascular event or diabetes.

Health Services, Systems, and Financing

9. Focused funding for particular diseases or programs—for example, TB or immunization—is a fact of life in many low-income countries. Using such funding to build health system capacity is feasible as well as desirable, but it is far from automatic. As capacity grows, the potential advantages of categorical programs are likely to fade while a more integrated (but still outcome-oriented) health system assumes responsibility for dealing with the relevant conditions.

10. Quality of clinical care makes an enormous difference, both to the cost of care and to health outcomes. Tangible actions can be taken to improve quality: important among them is having each provider do a few things well rather than many things poorly.

11. Strengthening capacity for surgery at the district hospital level is a frequently neglected priority. Major important uses of this capacity will be to deal with injuries and obstetrical emergencies.

12. In low-income countries public funding for health will remain highly constrained as a percentage of GDP for the foreseeable future. Targeting these funds to provide universal access to a limited number of interventions that are high priority for poor people is both efficient and equity enhancing, but it will require clear setting of priorities, particularly for incremental resources as they become available.

13. Middle-income countries can learn from the OECD experience that universal public financing of a substantial package of clinical care is both efficient and equity enhancing.

Research and Development

14. Impact evaluation of interventions in many domains is an essential priority and should be done around planned variations in implementation. One specific area of importance is evaluation of effective ways to manage lifelong drug use—for example, for AIDS, secondary prevention of vascular disease, diabetes, and major psychiatric disorders.

15. Public-private partnerships such as the Medicines for Malaria Venture and the International AIDS Vaccine Initiative provide promising models for developing important new drugs, vaccines, and diagnostic products to deal with the major diseases of poverty as well as the problem of drug resistance and microbial evolution more generally.

Development Assistance

16. Development assistance for health has begun to become performance based, and this trend should accelerate, along with making development assistance more stable and long term (contingent on performance). This change may involve at least a partial shift away from the sectorwide approaches to development assistance that recent evidence suggests may lead to neglect of focus on outcomes. It will require renewed attention to outcome measurement.

17. Resistance of the malaria parasite that is responsible for most deaths to chloroquine and SP is now widespread and rapidly increasing. A particular challenge is overcoming financial and institutional barriers to virtually complete replacement of those drugs with ACTs, which minimize resistance and can decrease transmission. Absent such an effort, malaria mortality is likely to continue rising. A centralized procurement mechanism receiving subsidies from development assistance agencies and making low-cost ACTs available to public and private supply chains globally would address this problem.

18. Investing in global capacity to respond effectively to a new influenza pandemic, particularly within the resource constraints of low-income countries, is a priority for the international system. Such capacity would include effective surveillance, surge manufacturing capacity for drugs and vaccines, stockpiles of drugs that could be used to attempt to contain epidemics, and mass media messages and public policies prepared in advance to be deployed if needed.

19. Because research and development is so important for health and because it is a classic international public good, a substantial fraction of incremental development assistance for health should go to research and development.

The content of these specific recommendations, and of recommendations throughout this volume, point to the enormous potential we now have to reduce further the human and financial burden of ill health. Scientific advance created this potential. Its more widespread realization requires the focused attention of health systems to finance and deliver priority interventions.

Background

Many countries, including all high-income ones, maintain vital registration systems that provide data (usually annual) on the number of deaths by cause, age, sex, and sometimes race. Some countries additionally compute years of life lost (or YLL) by cause, which assigns a number of years of life lost attributable to each cause that depends on the age of death and some relevant measure of life expectancy. As of the early 1990s, no similar estimates existed for many developing countries or for regional groupings of them. Experts on individual conditions or the relevant disease program at WHO generated estimates for the diseases of interest to them. When added up across diseases, however, such estimates exceeded, often by a factor of 2 or more, any plausible estimate of the total number of deaths occurring in each age group. DCP1 and the World Development Report 1993 (Lopez 1993 and World Bank 1993) generated estimates of the number of deaths by cause that were consistent with demographically determined death totals for eight regional groupings of countries. WHO collaborated closely on this work. The number of deaths from a disease is one measure of the magnitude of its burden, and YLL constitutes for many purposes a better measure. Neither takes account of the disability or suffering associated with a nonfatal disease.

The 1993 World Development Report also developed a variant of the quality-adjusted life year (QALY) from the health economics literature to add a disability dimension to YLLs in order to generate a more comprehensive measure of burden. The result, called a disability-adjusted life year, measures burden from a specific cause as the sum of years of life lost from that cause and the equivalent years of life lost (in a sense that is made quite specific) from the disability caused by the condition. Original publications on disease burden included estimates that discounted future events at 0 percent or at 3 percent per year. They also included estimates that weighted the value of a year of life uniformly across all age groups and estimates that placed greater value on middle-aged groups. These are labeled DALYs (r, k) with the first number indicating the discount rate in percent per year and the second indicating whether uniform or nonuniform age weights were used. The most widely reported variant on the DALY is the DALY (3,1)—that is, one that uses a 3 percent discount rate and nonuniform age weighting. This chapter and the companion volume report DALYs (3,0)—that is, with discounting but uniform age weighting.

Estimates of DALYs by cause for 1990 first appeared as appendix B of the 1993 World Development Report and, in expanded form, in Murray, Lopez, and Jamison (1994). Christopher Murray, Alan Lopez, and colleagues later produced updated estimates for 1990 and a fuller account of the methods used (Murray and Lopez 1996a, 1996b). The relative burden of different conditions as measured by numbers of deaths correlates highly with DALYs, but important exceptions exist. The massive burden of major psychiatric conditions, for example, is captured by DALYs but missed in estimates of deaths by cause or YLLs. Table 1.A1 summarizes the current estimates of deaths by cause in 2001 from Mathers, Murray, and Lopez (2006). Table 1.A2 shows disease burden in DALYs. Additional columns in these tables show the effect of including stillbirths on the percentage distribution of burden across conditions while leaving unchanged the other numbers (see Jamison and others 2006).

Disease burden can be assessed by risk factor as well as by disease or condition. An initial assessment of risk factor burden appeared in the 1993 World Development Report and later in Murray and Lopez (1997) and WHO (1996). WHO published a much fuller set of estimates in its 2003 World Health Report (WHO 2003b). Ezzati and others (2006) provided a substantial update adjusted to the same methodological assumptions as for deaths and DALYs, including use of DALYs (3,0).

Uses of Disease Burden Measures

DALYs are useful for informing health policy in at least six ways. Estimates of deaths by cause or YLL serve these same purposes, but for some uses less well.

1. Assessing performance. A country-specific (or regional) assessment of the burden of disease provides an outcome indicator that can be used over time to judge progress or across countries or regions to judge relative performance. The most natural comparison is to the development of national income and product accounts (NIPAs) by Simon Kuznets and others in the 1930s, which culminated in 1939 with a complete NIPA for the United Kingdom prepared by James Meade and Richard Stone at the request of the U.K. Treasury. NIPAs have, in the subsequent decades, transformed the empirical underpinnings of economic policy analysis. One leading scholar has put it this way:

   The national income and product accounts for the United States (NIPAs), and kindred accounts in other nations, have been among the major contributions to economic knowledge over the past half century. . . . Several generations of economists and practitioners have now been able to tie theoretical constructs of income, output, investment, consumption, and savings to the actual numbers of these remarkable accounts with all their fine detail and soundly meshed interrelations. (Eisner 1989, 1)

   Disease burden measures have the potential of serving a similar purpose for health policy.
2. Generating a forum for informed debate of values and priorities. The assessment of disease burden in a country in practice involves participation of a broad range of national disease specialists, epidemiologists, and, often, policy makers. Debating the appropriate values, say, for disability weights or for years of life lost at different ages helps clarify values and objectives for national health policy. Discussing the interrelations among diseases and their risk factors in the light of local conditions sharpens consideration of priorities.
3. Identifying national control priorities. Many countries now identify a relatively short list of interventions, the full implementation of which becomes an explicit priority for national political and administrative attention. Examples include interventions to control TB, poliomyelitis, HIV infection, smoking, and specific micronutrient deficiencies. Because political attention and high-level administrative capacity are in relatively fixed and short supply, the benefits from using those resources will be maximized if they are directed to interventions that are both cost-effective and aimed at problems associated with a high burden. Thus, national assessments of disease burden are one input in establishing a potential short list of control priorities. In the summary of the cost-effectiveness analyses reported in this volume, chapter 2 pays particular attention to identifying cost-effective interventions capable of averting a large disease burden.
4. Allocating training time for clinical and public health practitioners. Medical schools offer a fixed number of instructional hours; training programs for other levels and types of practitioners are likewise limited. A major instrument for implementing policy priorities is allocating this fixed-time resource well. Again that means allocation of time to training in cost-effective interventions in which disease burden is high.
5. Allocating research and development resources. Whenever a fixed effort will have a benefit proportional not only to the size of the effort but also to the size of the problem being addressed, estimates of disease burden become essential for formulating policy. Developing a vaccine for a broad range of viral pneumonias, for example, would have perhaps hundreds of times the effect of a vaccine against Hanta virus infection. Thus, information on disease or risk factor burden is one vital input (of several) to inform research and development resource allocation, as discussed in chapters 4 and 5.
6. Allocating resources across health interventions. Here disease burden assessment often plays a minor role; the task is to shift resources to interventions, which, at the margin, will generate the greatest reduction in DALY loss. When there are major fixed costs in mounting an intervention, as is the case with political and managerial attention for national control priorities, burden estimates are required to improve resource allocation. Likewise, major fixed costs may be associated with making the use of an intervention universal (or expanding it to cover a major percentage of the population), and if so, the cost-effectiveness of the expansion will depend in part on the size of the burden.

Results

Tables 1.A1 and 1.A2 convey summaries of deaths by cause and burden of disease in 2001, respectively.