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Informing the Future: Critical Issues in Health: Fourth Edition (2007)

Chapter: Public Health: The Big Picture

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Suggested Citation:"Public Health: The Big Picture." Institute of Medicine. 2007. Informing the Future: Critical Issues in Health: Fourth Edition. Washington, DC: The National Academies Press. doi: 10.17226/12014.
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Suggested Citation:"Public Health: The Big Picture." Institute of Medicine. 2007. Informing the Future: Critical Issues in Health: Fourth Edition. Washington, DC: The National Academies Press. doi: 10.17226/12014.
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Suggested Citation:"Public Health: The Big Picture." Institute of Medicine. 2007. Informing the Future: Critical Issues in Health: Fourth Edition. Washington, DC: The National Academies Press. doi: 10.17226/12014.
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Suggested Citation:"Public Health: The Big Picture." Institute of Medicine. 2007. Informing the Future: Critical Issues in Health: Fourth Edition. Washington, DC: The National Academies Press. doi: 10.17226/12014.
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Suggested Citation:"Public Health: The Big Picture." Institute of Medicine. 2007. Informing the Future: Critical Issues in Health: Fourth Edition. Washington, DC: The National Academies Press. doi: 10.17226/12014.
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Suggested Citation:"Public Health: The Big Picture." Institute of Medicine. 2007. Informing the Future: Critical Issues in Health: Fourth Edition. Washington, DC: The National Academies Press. doi: 10.17226/12014.
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Suggested Citation:"Public Health: The Big Picture." Institute of Medicine. 2007. Informing the Future: Critical Issues in Health: Fourth Edition. Washington, DC: The National Academies Press. doi: 10.17226/12014.
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Suggested Citation:"Public Health: The Big Picture." Institute of Medicine. 2007. Informing the Future: Critical Issues in Health: Fourth Edition. Washington, DC: The National Academies Press. doi: 10.17226/12014.
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Suggested Citation:"Public Health: The Big Picture." Institute of Medicine. 2007. Informing the Future: Critical Issues in Health: Fourth Edition. Washington, DC: The National Academies Press. doi: 10.17226/12014.
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Suggested Citation:"Public Health: The Big Picture." Institute of Medicine. 2007. Informing the Future: Critical Issues in Health: Fourth Edition. Washington, DC: The National Academies Press. doi: 10.17226/12014.
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Suggested Citation:"Public Health: The Big Picture." Institute of Medicine. 2007. Informing the Future: Critical Issues in Health: Fourth Edition. Washington, DC: The National Academies Press. doi: 10.17226/12014.
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Suggested Citation:"Public Health: The Big Picture." Institute of Medicine. 2007. Informing the Future: Critical Issues in Health: Fourth Edition. Washington, DC: The National Academies Press. doi: 10.17226/12014.
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Suggested Citation:"Public Health: The Big Picture." Institute of Medicine. 2007. Informing the Future: Critical Issues in Health: Fourth Edition. Washington, DC: The National Academies Press. doi: 10.17226/12014.
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Suggested Citation:"Public Health: The Big Picture." Institute of Medicine. 2007. Informing the Future: Critical Issues in Health: Fourth Edition. Washington, DC: The National Academies Press. doi: 10.17226/12014.
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Public Health: The Big Picture Public Health: The Big Picture The banner of public health unfurls to encompass a wide spectrum of sub- jects, and it is perhaps the most diverse area that the Institute of Medicine (IOM) investigates. Public health addresses widespread, population-level issues. These impor- tant and often contentious problems affect Americans from every walk of life, in every part of the country. Included in this category are widely publicized issues such as tobacco use, the challenges that disabled citizens face, food safety con- cerns, preparedness for pandemic disease, and approaches to health care policy in government. In these areas, the IOM’s role as an impartial intermediary is critical. Because the IOM is highly respected as an independent resource that can objectively eval- uate the science and evidence rather than being involved in politics or marketing, it is able to bring parties with widely differing viewpoints to the table and to craft well-researched, meaningful recommendations based on a firm understanding of the facts—and the risks and benefits of potential actions. Kicking the Tobacco Habit Since 1964, when the first Surgeon General’s report on smoking and health was released, a series of increasingly strong antismoking measures have cut the rate of smoking among U.S. adults by 58 percent. That cam- paign, which has saved millions of men and women from lung cancer, heart disease, and other smoking-related maladies, has been one of the most important public health success stories ENDING THE of the past several decades. TOBACCO PROBLEM Yet despite these achievements, more than one in five adults continue to smoke. In the United States, one-half of these 44.5 million people will die prematurely from a tobacco- related disease unless they stop smoking. This year, tobacco use will cause 440,000 deaths in the United States, includ- A BLUEPRINT ing 50,000 deaths from secondhand smoke. These smoking- FOR THE NATION related deaths take a greater toll than AIDS, alcohol, cocaine, heroin, homicide, suicide, motor vehicle crashes, and fires com- bined. Their cost to the nation and the health care system is enormous. 27

Informing the Future: Critical Issues in Health This year, tobacco use will cause To address this, the American Legacy Foun- 440,000 deaths in the United States, dation asked the IOM to conduct a major study including 50,000 deaths from of tobacco use in the United States. The resulting secondhand smoke. These smoking- report, Ending the Tobacco Problem: A Blueprint for related deaths take a greater toll the Nation (2007), outlined the strategies needed than AIDS, alcohol, cocaine, heroin, to build on past antismoking efforts and expand homicide, suicide, motor vehicle that success in the coming decades. crashes, and fires combined. While fewer people are smoking, the rate of decline might be leveling off. Teenagers are tak- ing up and continuing to smoke at an alarming rate, which is one of the largest obstacles to achieving a permanent long-term reduction in tobacco use. The re- port proposed a two-pronged strategy for tobacco control. First, traditional measures that have proven to be effective should be strength- ened. These include supporting comprehensive state tobacco control programs, increasing excise taxes, strengthening smoking restrictions, limiting youth access to tobacco products, intensifying prevention interventions, and increasing access to smoking cessation programs. 180 Rate of Smoking Initiation per 1,000 Age 12–17 120 Ages 18–25 60 0 19 5 19 6 19 7 19 8 19 9 19 0 19 1 19 2 19 3 19 4 19 5 19 6 19 7 19 8 19 9 19 0 19 1 19 2 19 3 19 4 19 5 19 6 19 7 19 8 19 9 19 0 19 1 19 2 19 3 19 4 19 5 19 6 19 7 19 8 20 9 20 0 20 1 20 2 03 6 6 6 6 6 7 7 7 7 7 7 7 7 7 7 8 8 8 8 8 8 8 8 8 8 9 9 9 9 9 9 9 9 9 9 0 0 0 19 Year Smoking initiation rites among adolescents and young adults, 1965 to 2003. SOURCE: Ending the Tobacco Problem: A Blueprint for the Nation, p. 48. 1.04 28

Public Health: The Big Picture The second prong involves significantly boosting federal involvement in antismoking efforts. To ensure that any success in curtailing tobacco use endures over time, Congress and other policy makers need to change the legal structure of tobacco policy. Congress should give the FDA (or another regulatory agency) broad authority to regulate the manufacture, distribution, marketing, and use of tobacco products. The public and private sectors must work together to strengthen and imple- ment tobacco control measures that have proven to be effective. Congress should empower state and federal governments to employ new weapons in the fight against tobacco use. Taking these steps will put the United States on a necessary and permanent course toward ending the tobacco problem. The New Face of Disability More than 40 million Americans live with a disability. In fact, most Ameri- cans will be affected by disabilities at some point in their lives, either their own or those of family members or friends. Although members of the “Baby Boom” generation will . . . outdated public policies and surely benefit from medical advances and inter- practices all too often create obstacles ventions that did not exist in previous decades, to independence and community the sheer number of older adults will strain both involvement for people with retirement and health care programs as this gen- disabilities. eration ages. In 1991 and again in 1997, the IOM released reports that highlighted dis- ability as a pressing public health issue. Since that time, the country has made progress. Policy makers, clinicians, researchers, and others have increasingly recognized that environmental obstacles often contribute to disability. For ex- ample, the Americans with Disabilities Act has helped increase public awareness of the physical and social barriers faced by people with disabilities and, in many cases, has helped to eradicate them. Advances in science and engineering have led to better assistive technologies, which make it easier for individuals with dis- abilities to lead productive, independent lives. Still, outdated public policies and practices all too often create obstacles to independence and community involve- ment for people with disabilities. To better understand disability in the United States, the Centers for Disease Control and Prevention, the Department of Education, and the National Institutes of Health asked the IOM to assess the current situation and provide recommen- dations for improvement. Among other recommendations in the resulting report, 29

Informing the Future: Critical Issues in Health 30 25 20 Percent 15 10 5 0 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 Year Bathing/Showering Dressing Eating Getting out of bed/chairs Walking Using toilet Percentage of community-dwelling Medicare beneficiaries, age 65 and over, who have difficulty in performing selected personal care activities without help or special equipment, 1992 to 2003. SOURCE: The Future of Disability in America, p. 74. 3-7 The Future of Disability in America (2007), the IOM called on Congress and appropri- ate federal agencies to improve coverage of assistive technologies and services and to eliminate the requirement that individuals who qualify for Social Security disability benefits must wait 24 months before becoming eligible for Medicare. Disability, in the form of limited activities and restricted participation in so- cial life, is not an unavoidable result of injury or chronic disease. It results, in part, from the choices that society makes about working conditions, health care, transportation, housing, and other aspects of the environment. The United States faces important decisions that could reduce, or increase, the extent to which people with disabilities can live independently and be involved in their communi- ties. Inaction will lead to diminished quality of life, increased stress on individu- als and families, lost productivity, and higher costs of care. Safe Seafood Seafood is a tremendously important part of the American menu. It is nutrient-rich and widely available to most Americans. High in protein and micro- 30

Public Health: The Big Picture nutrients and low in saturated fat, it can be an excellent contribution to a well- balanced diet. However, seafood is also the major source of human exposure to contaminants, such as methylmercury, that may be harmful to pregnant women and young children. Eating seafood can also expose consumers to contaminants such as dioxin and polychlorinated biphenyls (PCBs), as well as microbial infec- tions from the consumption of raw or undercooked fish and shellfish. The chal- lenge for consumers is to sort through information on the benefits and risks of seafood and, ultimately, make informed decisions about what they eat. In response to a request from the National Oceanic and Atmospheric Administration, the IOM formed a committee to review evidence on the benefits and risks associated with sea- food consumption. The committee’s report, Seafood Choices: Balancing Benefits and Risks (2007), provided comprehensive guidance about how to safely include seafood in diets. The report affirmed current government recommenda- tions that women who are pregnant, or wish to become preg- nant, should avoid consumption of lean, predatory fish that are sources of methylmercury, such as swordfish, shark, king mackerel, and tilefish. They should also limit their consump- tion of albacore, or “white,” tuna. However, the report also suggested that most people can gain nutritional benefits from seafood, if they minimize their risk of exposure to contaminants by selecting a variety of fish and shellfish in amounts that fall within current dietary guidelines. Because seafood supplies and cultivation practices change constantly, it would be difficult for federal agencies to develop a list of “good fish” and “bad fish” that would not quickly become obsolete. However, the benefits and risks for broad categories of seafood are relatively consistent: • Lean fish are good sources of protein, are low in saturated fat and choles- terol, and provide moderate amounts of omega-3 fatty acids. Predatory fish with long life spans—such as swordfish, shark, and tilefish—contain levels of methylmercury that are too high for pregnant and breast- feeding women and young children. • Fatty fish, such as salmon, are good sources of protein and provide the highest amounts of omega-3 fatty acids. They can also contain higher levels of saturated fat and can accumulate greater amounts of contami- nants such as dioxin and PCBs, depending on the source. However, their methylmercury burden is lower than that of many lean fish. 31

Informing the Future: Critical Issues in Health Age/Gender Group 12 years and under 13 years and over Female Male Could become pregnant, pregnant, or lactating Yes No Do you consume locally caught seafood? At risk for heart disease Yes No Yes No Evidence for additional benefits of seafood consumption to those at risk for heart disease is too weak to Contaminants in seafood warrant special advice vary according to local conditions; consume Do you consume locally caught locally caught seafood seafood? only if appropriate after checking your state advisories Yes No Contaminants in seafood vary according to local conditions; consume locally caught seafood only if appropriate after checking your state May benefit from consuming seafood, especially advisories those with relatively higher concentrations of EPA and DHA. Consume seafood regularly, e.g., two 3-ounce A reasonable intake would be two 3-ounce servings weekly. servings (or for children, age-appropriate servings) but can safely consume 12 ounces per week. If consuming more than two servings per week, Can consume up to 6 ounces (or for children, choose a variety of seafood types. age-appropriate servings) of white (albacore) tuna per week and should avoid large predatory fish There may be additional benefits from including such as shark, swordfish, tilefish, or king mackerel. seafood comparatively high in EPA and DHA. Example of a decision pathway for consumer guidance. SOURCE: Seafood Choices: Balancing Ben- efits and Risks, p. 254. 7-2 new version 32

Public Health: The Big Picture • Shellfish and crustaceans are good sources of protein and low in satu- rated fat, although some contain moderate amounts of cholesterol. They present the greatest risk of microbial infection if eaten raw. • For all seafood categories, levels of contaminants such as dioxin and PCBs in commercially obtained fish generally do not pose health risks when consumed in amounts recommended by federal agencies. These contaminants tend to be geographically specific. State advisories are in- tended to alert the public about contaminated fish and shellfish from regional and local sources. One of the biggest obstacles to these recommendations lies in disseminating them. Consumers need information to weigh the nutritional benefits against risks of contaminant exposure from various types of fish and shellfish. Consumers also need to be informed of the trade-offs of substituting seafood for other protein sources. For example, healthy young women who are, or wish to become, pregnant should avoid . . . the report also suggested that certain types of fish that are higher in methylmer- most people can gain nutritional cury, but this does not need to be a concern for benefits from seafood, if they men. Choosing a serving of salmon instead of a minimize their risk of exposure to serving of fatty beef will lower a woman’s intake contaminants by selecting a variety of of saturated fat and cholesterol and boost her in- fish and shellfish in amounts that fall take of omega-3 fatty acids, but it also will reduce within current dietary guidelines. her iron intake and may increase her exposure to methylmercury slightly. Selecting canned albacore tuna instead of salmon will decrease her exposure to dioxin, but it may increase her exposure to methylmer- cury. Knowing the trade-offs will enable consumers to attain a smart and healthy balance. Next-Generation Research Most U.S. citizens enjoy a level of health and well-being today that was un- imaginable a century ago. Simple public health measures such as sanitation, im- proved hygiene, and workplace safety have led to huge reductions in the spread of disease and serious injuries. Scientific and medical advances have led to the development of new vaccines, drugs, and clinical procedures. Huge gains have been made, and most recently, a growing understanding of the human genome is playing a vital role in extending the duration and improving the quality of hu- man life. Today’s detailed study of human genetics is forcing scientists to look at dis- ease as a complex problem. Instead of focusing on one factor—a virus or toxin, 33

Informing the Future: Critical Issues in Health for example—scientists are now focusing on interacting factors involving social, behavioral, and genetic conditions, which may work in concert to influence health. Many researchers are convinced that this more holistic approach may yield scores of medical breakthroughs in the future. The potential benefit to health—and the well-being of the health care system—is enormous. The IOM report Genes, Behavior, and the Social Environment: Moving Beyond the Nature/Nurture Debate (2006) examined a number of well-described gene– environment interactions, reviewed the state of the science in researching such interactions, and recommended priorities for both future research and the needs of the research workforce, its resources, and its infrastructure. The report found that a number of far-reaching changes, specifically in the development of interdisciplinary research, are required if significant strides are to be made. The National Institutes of Health should encourage research that incorpo- rates the study of key environmental, social, and behavioral fac- tors over a lifetime. For example, certain social factors such as educational attainment, income, and workplace conditions have been consistently linked with health outcomes. Behavioral and psychological factors include smoking, drinking, and eat- ing habits as well as physical activity and temperament. DNA sequence variation, structural chromosomal changes, and gene expression also affect health outcomes. A research ap- proach that truly transcends disciplines in order to deal with these, as well as other factors, has the potential to generate a far deeper understanding of how human beings remain healthy or become ill in the real world. The Threat of Pandemic Flu The infamous 1918 influenza pandemic killed at least 20 million people, more than any other disease outbreak in history. It was by no means the first lethal flu pandemic, and most experts believe it will not be the last. There is no question that the United States is in a better position to deal with another outbreak than it was a century ago: scientists have a better understanding of the viruses them- selves, and there are effective vaccines and antiviral drugs to forestall infection. Yet the world remains vulnerable to pandemic diseases, especially in this age of frequent global travel. 34

Public Health: The Big Picture However, there are tools to help mitigate the effects of a pandemic. In Model- ing Community Containment for Pandemic Influenza: A Letter Report (2006), the IOM committee suggested that, based on computer models and analyses of past flu outbreaks, community-wide intervention such as isolating infected people or implementing a voluntary quarantine could be effective in decreasing the rate of illnesses and deaths during the next pandemic flu. The committee cautioned, however, that government and community leaders should not overstate the evidence base for these strategies and that a good spokesperson or leader on the subject should be The infamous 1918 influenza appointed. After the report’s release, the CDC re- pandemic killed at least 20 million leased guidance on community containment during people, more than any other disease pandemic influenza based on IOM’s advice. outbreak in history. It was by no means the first lethal flu pandemic, Barring complete containment if an influenza and most experts believe it will not pandemic does strike, public health officials will be the last. need to employ multiple measures to reduce its impact. Given that vaccines and antiviral medications will be in short supply in the early days of a pandemic, the public might turn to using facemasks to help prevent or slow the transmission of influenza. Based on the assumption that efforts to produce and stockpile sufficient sup- plies of disposable masks and/or respirators may fall short in the event of a pan- demic, the U.S. Department of Health and Human Services requested that an IOM committee examine the potential reuse of medical masks and N95 respirators. The committee’s report, Reusability of Facemasks During an Influenza Pandemic: Facing the Flu (2006), highlighted the fact that very little is known about the practicality or effectiveness of disinfecting and reusing either medical masks or respira- tors. There is no known simple and reliable way to decon- taminate these devices that would enable people to safely use them more than once. This uncomfortable statement of fact resulted in media coverage ranging from WebMD to the New York Times, highlighting the potentially dire state of the nation’s ability to respond to an influenza pandemic. Funda- mental research both in the epidemiology of influenza and in the material properties of medical masks and respirators is needed before methods of disinfection and reuse can be developed. 35

Informing the Future: Critical Issues in Health Filtering facepiece respirator. SOURCE: Reusability of Facemasks During an Influenza Pandemic: Facing the Flu, p. 29. Encouraging Organ Donation Every year, thousands of people in the United States die while waiting for an organ transplant. These deaths have become more common even as the number of organ donations has increased. In 1996, more than 4,000 people died waiting for an organ transplant; in 2005, the number was 7,000. Although the rate of organ donation in the United States has increased steadily since the late 1980s, organ donations continue to lag far behind the ever-increasing need. In 2005, 7,593 deceased donors provided 23,249 organs for transplantation, with an additional 6,896 living donors. Yet at the start of 2006, more than 90,000 people were waiting to receive organs, and approxi- mately 40,000 people are added to the organ transplant waiting lists each year. These shortages occur despite the fact that approximately 30,000 to 40,000 people who could be organ donors die each year. Most organs come from de- ceased donors whose deaths have been determined by neurologic criteria based on the irreversible loss of activity in the brain, including the brain stem. There are about 16,000 eligible donors whose deaths are declared in this way each year in the United States. Many more deaths are determined based on circulatory 36

Public Health: The Big Picture criteria, meaning an irreversible loss of heart function that leads to permanent cessation of blood circulation. It is estimated that at least 22,000 people who die of heart attacks outside of hospitals could be potential donors, if certain ethical and practical issues are resolved. Estimates indicate that each donor is worth In 1996, more than 4,000 people more than $1 million to society in reduced health died waiting for an organ transplant; care costs for dialysis and other medical interven- in 2005, the number was 7,000. tions and in increased quality of life for donor recipients. With such enormous, life-saving po- tential and societal gains at stake, how can people be encouraged to grant this valuable gift? In Organ Donation: Opportunities for Action (2006), an IOM committee urged federal agencies, nonprofit groups, and others to boost opportunities for people to record their decisions to donate, strengthen efforts to educate the public about the benefits of organ donation, and continue to improve donation systems. TABLE 2-4 Organ Donation, Transplantation, and Waiting List by Ethnicity Percentage Percentage of Waiting List Population of Total Transplant Distribution (%) Distribution Donations, Recipients, as of Ethnicity (%)a 2005b 2005c March 24, 2006 White 75.1 68.9 63 49.3 African American 12.3 14 18.5 27.4 Hispanic 12.5 13.2 12 15.8 Asian 3.6 2.6 4.0 5.5 American Indian/ Native Alaskan 0.9 0.5 0.7 0.9 Pacific Islander 0.1 0.1 0.4 0.5 Multiracial 2.4 0.7 0.7 0.6 aU.S. Census Bureau data, 2001. The population distribution adds up to more than 100 per- cent because of the option in the 2000 census to select multiple categories to accurately describe one’s ethnicity. bIncludes deceased and living donors. c0.7 percent of transplant recipients are of unknown ethnicity. SOURCE: OPTN (2006); U.S. Census Bureau (2001). Organ Donation, Transplantation, and Waiting List by Ethnicity. SOURCE: Organ Donation: Oppor- tunities for Action, p. 50. 37

Informing the Future: Critical Issues in Health Although the committee supported initiatives to increase donations from people whose deaths are the result of irreversible cardiac failure, it concluded that the nation is not yet ready for an opt-out system, where donation consent is presumed. Further, it argued that financial incentives—including direct pay- ments, coverage of funeral expenses, and charitable contributions—should not be used to increase donation rates. The organ donation imbalance is an issue that will remain in the spotlight for the foreseeable future. Everyone has a stake in fixing the problem—after all, nearly everyone is a candidate to be either a donor or a recipient at some point. The Value of Health: Weighing the Costs and Benefits of Regulation Government regulations are intended to ensure such things as the safety of the air Americans breathe, the food they eat, the water they drink, and many of the products they use. But in addition to the protections they afford, health and safety regulations also have costs associated with their implementation and en- forcement. In promulgating regulations, federal agencies must weigh these costs against the potential health benefits to be realized. Anticipating the impacts of regulations is challenging and includes a great many variables; information is incomplete and a number of analytic decisions must be made in the course of evaluating proposed regulations. In 2003, the U.S. Office of Management and Budget (OMB) instituted a new requirement: for health or safety regula- tions projected to have costs or benefits greater than $100 million, agencies must also estimate that regulation’s cost- effectiveness. Whereas cost–benefit analysis compares costs and benefits that are both expressed in monetary terms, cost- effectiveness compares monetary costs to benefits expressed as, for instance, cases of a particular illness or injury avoided, years of life extended, or improvements in health-related qual- ity of life. At the request of OMB and several other federal agencies, the IOM developed guidance on how best to con- duct cost-effectiveness analyses in the regulatory context. The resulting report, Valuing Health for Regulatory Cost- Effectiveness Analysis (2006), reviewed and made recommendations for using integrated measures of morbidity and mortality (quality-adjusted life years) to 38

Public Health: The Big Picture represent a regulation’s health impacts and for standardizing the calculation and reporting of information about cost-effectiveness. It also highlighted the data and research needed to improve regulatory cost-effectiveness analysis. Finally, the report considered the ethical implications of using cost-effectiveness analysis and integrated measures of health impact in regulatory policy development. 39

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