pub-diss14
lolo1339
annurev.publhealth.20.1.0.pdf
P1: KKK/SPD P2: APR/plb QC: KKK/anil T1: KKK
March 17, 1999 16:29 Annual Reviews AR080-Pref
Annu. Rev. Public Health. 1999. 20:xiii–xxx Copyright c© 1999 by Annual Reviews. All rights reserved
PUBLIC HEALTH IN THE TWENTIETH CENTURY: Advances and Challenges
Jonathan E. Fielding Schools of Public Health and Medicine, University of California at Los Angeles, Los Angeles, California 94090; Director of Public Health and Health Officer, Los Angeles County; e-mail: [email protected]
KEY WORDS: epidemiology, social environment, environment, occupational health, statistical methods, health status, disease burden, chronic disease, vaccines, longevity, health economics, evidence based practice, reproductive health
ABSTRACT Substantial advances in public health methods, practice, and the health of the public have occurred in the twentieth century. Some of the contributions most notable for their impact on mortality and longevity are vaccine development and widespread use, smallpox eradication, large reductions in communicable disease epidemics, and the rise and decline of several serious chronic diseases. Many methodological advances have facilitated better understanding of disease pro- cesses and opportunities for control. Epidemiological methods have advanced, but studies often ignore the determinants of health at the community level and above, leading to simplistic formulations of multiple risk factors contributing to chronic and other diseases and injuries. Occupational and environmental health developed as disciplines in this century, making significant contributions to cur- rent and future population health. The health care system became more organized, technologically sophisticated, and costly. New tools to assess health and the bur- den of ill health, to improve the effectiveness of interventions, and to measure economic effects of alternative investments promise greater efficiency and effec- tiveness for public health. An increasingly fragmented public health infrastructure must confront unprecedented challenges including dramatic global population growth, increased aging of the population associated with enhanced longevity, and possible irreversible changes in key environmental health determinants.
xiii 0163-7525/99/0510-xiii$08.00
A nn
u. R
ev . P
ub li
c H
ea lt
h 19
99 .2
0: xi
ii -x
xx . D
ow nl
oa de
d fr
om w
w w
.a nn
ua lr
ev ie
w s.
or g
A cc
es s
pr ov
id ed
b y
37 .4
2. 10
7. 23
8 on
0 4/
08 /1
9. F
or p
er so
na l
us e
on ly
.
P1: KKK/SPD P2: APR/plb QC: KKK/anil T1: KKK
March 17, 1999 16:29 Annual Reviews AR080-Pref
xiv FIELDING
INTRODUCTION
The threshold of a new century is an opportune time to review public health advances over the past 100 years. Some of the contributions most notable for their impact on mortality and longevity are vaccine development and widespread use, smallpox eradication, large reductions in communicable disease epidemics, and the rise and decline of several serious chronic diseases. But advances in public health are many, numbering more than can be described in one article. Nor can this article do justice to the interrelatedness of advances in methods and in interventions. Many advances in methods enabled the understanding of basic disease mechanisms and provided tools to better measure health and economic intervention outcomes. These advances in turn allowed more effective public health interventions.
Companion to the advances are challenges, both unfulfilled and new. This review highlights some challenges that constitute barriers to effective public health interventions or improved practice. United States is the primary focus, but some global challenges for which responses could strongly affect health in the United States are also addressed.
ADVANCES IN METHODS
Progress in advancing public health has been achieved that would have been unthinkable at the end of the nineteenth century. In significant measure progress is both delineated by and due to improvements in methods on how to determine health burden, how to think about and identify causative factors for health prob- lems, and how to measure exposures, health, and the effects of interventions.
Our view of what causes health and disease is largely shaped by our meth- ods of ascertainment. Method development and use are in turn shaped by the prevailing view of the range of possible causative factors. The infectious dis- ease paradigm, the product of the revelations of the late nineteenth century that continued to play a dominant role well into the twentieth century, was reductionistic. Every specific identifiable agent caused a well-described set of physiological and pathological findings. Koch’s postulates had to be fulfilled. Finding these agent-disease pairs for diseases such as typhoid, cholera, and syphilis was considered essential to construct interventions to break the chain of transmission.
Changing Paradigms Successes in reducing the toll of infectious diseases led to unprecedented in- creases in longevity during the first half of the century. A new set of health prob- lems became the major causes of mortality and disability. As their toll mounted, heart disease, stroke, cancer, diabetes mellitus, and chronic respiratory and other
A nn
u. R
ev . P
ub li
c H
ea lt
h 19
99 .2
0: xi
ii -x
xx . D
ow nl
oa de
d fr
om w
w w
.a nn
ua lr
ev ie
w s.
or g
A cc
es s
pr ov
id ed
b y
37 .4
2. 10
7. 23
8 on
0 4/
08 /1
9. F
or p
er so
na l
us e
on ly
.
P1: KKK/SPD P2: APR/plb QC: KKK/anil T1: KKK
March 17, 1999 16:29 Annual Reviews AR080-Pref
TWENTIETH CENTURY PUBLIC HEALTH xv
diseases received increased attention from researchers, clinicians, and funding sources. Epidemiological studies revealed neither an infectious origin nor a single other agent or deficiency in most cases.
The risk factor paradigm emerged as multiple underlying factors were shown to confer independent risks for one or more of these diseases. During the second half of the century, these risk factors were broadly explored to better measure and characterize them and to quantify their contribution to the ill-health of the population.
Research Syntheses Important advances have been made in methods for reviewing and summarizing multiple studies that assess the importance of risk factors, whether in the med- ical or public health context (27). These methods, imported in the 1980s from social and agricultural sciences, are collectively termed meta-analyses, a par- ticular kind of research synthesis. Their use results in stronger inferences and better-characterized dose-response relationships, bringing stronger evidence to programmatic and policy decision-making processes. There are, however, se- rious limitations of the risk factor paradigm. As explicated by Schwartz et al, they include (a) disproportionate attention to risk-disease relationships rather than to explanation of causal processes, (b) lack of attention to risk factor an- tecedents, and (c) preoccupation with the individual and with one point in time (31). These authors call for improved methods that can systematically address multiple levels of organization, including communities and nations, broader historical, social, and physical environment perspectives, and consideration of dynamic processes that link antecedents and later outcomes.
Methodologic progress has been made in this century in how to assess the social environment (42). Yen & Syme recommend using newer methods to conduct more mixed level studies that simultaneously address individual vari- ables and variables capturing aspects of the social and economic environment of groups and communities. However, despite increased methodological so- phistication in measuring environmental factors, ecologic studies have many methodologic problems that can limit causal inference (25).
Weighing Costs and Benefits In this century we have greatly expanded quantitative economic analysis, in- cluding how to assess alternative use of capital, whether for private gain or for public benefit. Methods to determine the relative return on investment of different approaches to improve the public’s health have been developed and refined. Borrowing from techniques developed in the private sector, public health analysts now use the ratio of costs to benefits to help assess alterna- tive investments. Sometimes the benefits can be expressed in dollars, allowing
A nn
u. R
ev . P
ub li
c H
ea lt
h 19
99 .2
0: xi
ii -x
xx . D
ow nl
oa de
d fr
om w
w w
.a nn
ua lr
ev ie
w s.
or g
A cc
es s
pr ov
id ed
b y
37 .4
2. 10
7. 23
8 on
0 4/
08 /1
9. F
or p
er so
na l
us e
on ly
.
P1: KKK/SPD P2: APR/plb QC: KKK/anil T1: KKK
March 17, 1999 16:29 Annual Reviews AR080-Pref
xvi FIELDING
determination of net costs, net benefits, and time required to recoup an invest- ment (20). Often the benefits are expressed in health. Metrics to measure the degree of health improvement have evolved from outcomes expressed in years- of-life gained to quality-adjusted life years (QALYs). Increasingly, decisions on alternative interventions, whether preventive services or public policies on issues from tobacco control to environmental regulation, utilize these tech- niques (12). However, even the best estimates incorporate many assumptions and are difficult to extrapolate from a small number of studies to other settings, populations, and different levels of baseline risk or exposure.
Disease Burdens Important methodological advances have occurred in quantifying the aggregate burden of disease. Early refinements included improved systems of classifying causes of death, standardized death certificates, standardized mortality rates and then age adjusted mortality rates. Limitations included not considering mor- bidity or disability and not considering conditions that greatly affected function (e.g. arthritis, cerebral palsy, schizophrenia) but were not common causes of death. The most recent refinement to these shortcomings started in the late 1980s, when the World Bank and the World Health Organization supported the development of a reliable assessment of epidemiological conditions and the burden of disease. The common metric developed to aggregate disease burden was the disability-adjusted life year or DALY. This measure combines the bur- den from premature mortality with the burden of living with disability, a factor of growing importance in developing countries with aging populations (41). Information from these analyses will be used by policy-makers in setting prior- ities at the national and regional level. International development agencies can use these methods to weigh the potential for benefit of alternative investments in developing countries.
Health Status Many public health leaders have reinforced the notion that health is more than lack of disease and that health status needs to be defined as a positive indi- vidual attribute. Refinement of methods to assess health status has focused on measures of the quality of health, a concept that overlaps with the quality of life. Among the dimensions incorporated into some of the newer scales/indexes are physical functioning, social functioning, psychological functioning, pain, energy, and cognitive and psychological functioning (39). Some of these scales have been incorporated into national sample surveys on health and health care. Availability of these reliable and valid comprehensive health measures supports monitoring, evaluation, and improvement of health care and public health pro- grams and policies. Such data make it possible to answer questions ranging
A nn
u. R
ev . P
ub li
c H
ea lt
h 19
99 .2
0: xi
ii -x
xx . D
ow nl
oa de
d fr
om w
w w
.a nn
ua lr
ev ie
w s.
or g
A cc
es s
pr ov
id ed
b y
37 .4
2. 10
7. 23
8 on
0 4/
08 /1
9. F
or p
er so
na l
us e
on ly
.
P1: KKK/SPD P2: APR/plb QC: KKK/anil T1: KKK
March 17, 1999 16:29 Annual Reviews AR080-Pref
TWENTIETH CENTURY PUBLIC HEALTH xvii
from the impact of tobacco prices on smoking to the effects of various managed care approaches on key dimensions of health and use of health services.
Surveying Population Health A critical public health achievement has been the development of national sur- veys of our population. National sample surveys such as the National Health Interview Survey and the National Health Examination Survey have provided reliable, representative information on perceived health status, health behav- iors and risks, and use of health services by different segments of our popula- tion. Data from these sources have become an indispensable tool for assessing changes in key health behaviors, use of preventive services, and the more gen- eral use of personal health care services.
Evidence-Based Practice An important advance that straddles methods and practice is the movement from opinion to stronger evidence in developing recommendations for appropriate practice, both for clinicians and public health practitioners (40). Evidence-based approaches put the onus on clinicians and researchers to demonstrate that what they do is effective and that benefits outweigh harms. Methods established by the Canadian Task Force on the Periodic Health Examination and refined by the US Preventive Services Task Force in the mid 1980s were systematically ap- plied to develop a coherent set of practice recommendations for asymptomatic patients. Only a few screening tests were recommended, in contradistinction to recommendations of other groups not using this evidence-based approach. Patient education and counseling regarding health behaviors emerged from the evidence-based reviews as important components of the periodic examinations of healthy individuals. The evidence-based approach is now being adapted for developing recommendations about preventive services provided at the com- munity level. Overall, evidence-based methods promise to improve the health return on our investments in improving the nation’s health and to reduce ex- penditures on interventions that have been found to be ineffective.
Toxicology and Risk Assessment Toxicology as a discipline to explain the health effects of chemical and physical agents only developed in this century. As described in this volume by Gochfeld & Goldstein (pp. 35–53), advances in chemistry, biology (including cell biology and molecular biology), and epidemiology supported identification of health effects of many molecular structures but also exploded our understanding of bi- ologic mechanisms. The last two decades have seen corresponding advances in risk assessment methodologies and their use in developing environmental health policies. Better estimates of exposure and susceptibility undergird computer- based modeling. Biomarkers of exposure, susceptibility, and effect are valuable
A nn
u. R
ev . P
ub li
c H
ea lt
h 19
99 .2
0: xi
ii -x
xx . D
ow nl
oa de
d fr
om w
w w
.a nn
ua lr
ev ie
w s.
or g
A cc
es s
pr ov
id ed
b y
37 .4
2. 10
7. 23
8 on
0 4/
08 /1
9. F
or p
er so
na l
us e
on ly
.
P1: KKK/SPD P2: APR/plb QC: KKK/anil T1: KKK
March 17, 1999 16:29 Annual Reviews AR080-Pref
xviii FIELDING
both for designing exposure control and for assessment of outcomes of poli- cies and practices to restrict exposure. The effects of environmental lead and asbestos are but two tragic examples of preventable environmentally induced illness and death.
Computers and Information Systems We end the twentieth century with a computational ability unimaginable to a public health professional even 25 years ago. This capability has made possible studies of many thousands of individuals with a virtually unlimited number of variables per individual. It also permits the modeling of such a complex phenomenon as global warming when a large number of variables from a wide range of sources need to be analyzed to discern important but subtle changes in health determinants.
Many research projects and public health programs can maintain large data- bases and sophisticated but easy-to-use application software on a personal com- puter costing only a few thousand dollars. It is not possible to overestimate the increase in capability and efficiency that the computer revolution has brought to public health investigation, monitoring, and evaluation. For example, tapes of national surveys of health and health care expenditures that can be analyzed are accessible to almost any public health professional or trainee at minimal cost.
The same revolution has brought improvement in clinical databases. The automated medical record is finally in place in some organizations after many false starts. Large populations served by many managed care organizations can be analyzed to understand the health and service utilization effects of changes in financing, organization, technology, and organization-imposed constraints. Clinical databases permit more refined analyses of practices associated with good clinical and global health outcomes.
Social Marketing One of the most important advances in public health is the purposeful use of media to effect changes in individual health behaviors and social or po- litical environments that influence decisions about health-related policies or programs. Mass media strategies can be influential at four levels–individual, networks such as families, organizations (e.g. schools, churches), and commu- nities (9, 23). Public health agencies are increasing use of social marketing, social change management strategies to convince specific target audiences to adopt an idea, practice, or product. To date, the database is limited, and results are not all consistent. However, there are a number of well-evaluated social marketing success stories, including some contraceptive, immunization, and diarrheal disease control social marketing projects in developing countries, the
A nn
u. R
ev . P
ub li
c H
ea lt
h 19
99 .2
0: xi
ii -x
xx . D
ow nl
oa de
d fr
om w
w w
.a nn
ua lr
ev ie
w s.
or g
A cc
es s
pr ov
id ed
b y
37 .4
2. 10
7. 23
8 on
0 4/
08 /1
9. F
or p
er so
na l
us e
on ly
.
P1: KKK/SPD P2: APR/plb QC: KKK/anil T1: KKK
March 17, 1999 16:29 Annual Reviews AR080-Pref
TWENTIETH CENTURY PUBLIC HEALTH xix
California anti-tobacco campaign (3), the Partnership for a Drug Free America television campaign, and efforts to promote the notion of a “designated driver.” These justify the conclusion that thoughtful use of media can substantially advance public health objectives.
Unraveling Health Determinants Among the most critical public health challenges for the twenty-first century will be to fathom how the major determinants of population health, the social, physical, and economic environments, health behaviors, and genetics interact to affect the health of populations. This difficult untangling will require new methods of inquiry and new study designs complemented by innovative meth- ods that bridge disciplines. We may need to follow large numbers of individuals over long periods of time, perhaps starting prenatally. Multiple dimensions of an individual’s physical, cultural, and social environment and her interaction with these will have to be surveyed at frequent intervals. Hitching the new molecular biology to approaches being refined by social and political scientists for assessing community health is a formidable but necessary challenge to ex- plore a full range of determinants of population health. It appears likely that many aspects of our genetic constitution, always considered an immutable indi- vidual and population health determinant, will be manageable, both prenatally and postnatally. This new frontier has great potential to improve health but poses formidable ethical dilemmas.
ADVANCES IN THE HEALTH OF THE PUBLIC
Advances in the public’s health come in many forms. We start with the health outcomes of improved interventions but also describe some products and efforts to better control some specific risk factors such as tobacco and alcohol and other drugs. We also describe changes and challenges in the public health system and in the personal health care delivery system.
Increased Longevity Improved methods to assess health and disease, growth of analytic capacity and tools, and technological advances in biology and chemistry, including in- sights into structure and function at the molecular level, have all made possible improvements in the life span of the average US resident. Longevity in the United States and other industrialized countries has increased more in this cen- tury than in any past century, and by a wide margin. In 1900 average longevity was 47 years (30). In 1996 it had increased to 76.1 years (2), a remarkable 62% increase. Improvements are equally striking for the older population. An individual reaching age 65 in 1900 could expect to live an additional 11.9 years,
A nn
u. R
ev . P
ub li
c H
ea lt
h 19
99 .2
0: xi
ii -x
xx . D
ow nl
oa de
d fr
om w
w w
.a nn
ua lr
ev ie
w s.
or g
A cc
es s
pr ov
id ed
b y
37 .4
2. 10
7. 23
8 on
0 4/
08 /1
9. F
or p
er so
na l
us e
on ly
.
P1: KKK/SPD P2: APR/plb QC: KKK/anil T1: KKK
March 17, 1999 16:29 Annual Reviews AR080-Pref
xx FIELDING
but that expectancy increased to 17.5 years by the early 1990s, a 47% increase (14). While these statistics are mirrored in many developed countries, we have reminders of the fragility of this progress. Many sub-Saharan African nations are in the process of precipitous increases in mortality due to the devastation of AIDS. Dissolution of the Soviet Union led to a precipitate drop of six years in male life expectancy due to increases in poverty, social disintegration, and environmental pollution, superimposed on high rates of alcoholism and tobacco use (22).
Reduced Toll of Infectious Diseases Public health measures such as pure food and water, and development of im- munizations against many serious diseases such as polio and smallpox, coupled with enhanced economic conditions, are together credited with substantial re- ductions in the burden of infectious diseases. However, globalization of food supply, growing antibiotic resistance, and appearance of new diseases, partic- ularly HIV infection, threaten to again increase the toll of infectious agents.
Reduction in Chronic Disease Mortality Identification of the precipitating mechanisms for chronic diseases responsible for a high percentage of premature deaths has led to effective public health and medical interventions to reduce their mortality rates. For example, public health organizations joined organized medicine in developing effective programs to find and treat those with high blood pressure and with abnormal lipid profiles, and to decrease tobacco use. Age-adjusted cardiovascular mortality rates have declined 30%–50% from their peak in most highly industrialized countries, including the United States (33). Declines in cerebrovascular death rates are even sharper than for cardiovascular disease in the United States. However, public health efforts to address other important proximate determinants of major chronic diseases–risk factors such as lack of adequate physical activity and unhealthful nutrition–have been less successful.
Risk Factor Reduction: The Example of Tobacco Control The story of tobacco control exemplifies the challenges and successes of American public health in the twentieth century. Reduced tobacco use has made a substantial contribution to the decline of cardiovascular disease and many cancers and respiratory diseases (7). Cigarette use increased from almost zero in 1900 to a peak of 4345 cigarettes per capita in 1963. Although some public health officials suspected a strong link between tobacco use and disease, it was not until the late 1950s that a sufficient body of epidemiologic studies was accumulated to mount a public health information program, culminating in the first Surgeon General’s Report on Smoking and Health in 1964 (32). Greater investment in studies of tobacco use identified it as the single greatest contributor to premature death, with an annual economic toll of $50 billion
A nn
u. R
ev . P
ub li
c H
ea lt
h 19
99 .2
0: xi
ii -x
xx . D
ow nl
oa de
d fr
om w
w w
.a nn
ua lr
ev ie
w s.
or g
A cc
es s
pr ov
id ed
b y
37 .4
2. 10
7. 23
8 on
0 4/
08 /1
9. F
or p
er so
na l
us e
on ly
.
P1: KKK/SPD P2: APR/plb QC: KKK/anil T1: KKK
March 17, 1999 16:29 Annual Reviews AR080-Pref
TWENTIETH CENTURY PUBLIC HEALTH xxi
(1993 dollars) in direct costs and an additional $47 billion in lost productiv- ity. Public health agencies, health professional organizations, and voluntary agencies all worked to educate the public, to secure funding to develop better cessation and prevention methods, and to help smokers to quit.
Recognition of the adverse effects of environmental tobacco smoke trans- formed the public policy debate about tobacco use because smokers were harm- ing others, including fetuses, infants, and children. Reducing tobacco exposure became a broad population health goal, with smoking interdicted in many public places and most work sites.
The prolonged multifaceted efforts to reduce tobacco use have reduced preva- lence rates to about 25% of adults, with per capita consumption in 1997 down 45% from peak levels. However, smoking among youth and college students is registering rapid increases. Between 1991 and 1997, the prevalence of smoking increased from 21% to 30% among tenth graders (7). New tactics, including state initiatives to tax tobacco and use proceeds for control efforts, and litiga- tion, culminating in the 1998 settlement whereby tobacco companies will pay states $206 billion over 25 years with few restrictions on how money can be used, suggest the need for broad coalitions with common objectives and a wide range of policy and political tactics.
Alcohol and Illicit Drugs We have not seen the same success with other drugs. The toll of alcohol rivals that of tobacco. However, with the exception of the short-lived period of pro- hibition, during which alcohol consumption fell significantly, control efforts have been of uneven effect. More recent control efforts, particularly efforts to change policies such as excise taxes, advertising restrictions, and warnings have been largely unsuccessful (26). An exception is the important achievement of a decline in alcohol-related traffic fatalities, with a 32% drop between 1982 and 1996 attributed to reductions in legal blood alcohol concentrations for drivers, increases in minimum legal drinking age, sobriety checkpoints, administrative license revocation, designated driver and responsible beverage service programs (5). Control of illicit drugs must be considered a failure in the twentieth century. We have succeeded in better estimating their toll and unlocking how they affect brain chemistry, but neither prevention efforts nor border control nor increased treatment program capacity and use have convincingly altered their impact.
Vaccines We have developed a myriad of vaccines against many of the infectious diseases that cause substantial morbidity and mortality in the industrialized world. Vac- cines of high effectiveness now exist for most infectious diseases that caused significant morbidity and mortality at the beginning of the century. Vaccines are credited with virtually eliminating polio in this country and with accelerating the
A nn
u. R
ev . P
ub li
c H
ea lt
h 19
99 .2
0: xi
ii -x
xx . D
ow nl
oa de
d fr
om w
w w
.a nn
ua lr
ev ie
w s.
or g
A cc
es s
pr ov
id ed
b y
37 .4
2. 10
7. 23
8 on
0 4/
08 /1
9. F
or p
er so
na l
us e
on ly
.
P1: KKK/SPD P2: APR/plb QC: KKK/anil T1: KKK
March 17, 1999 16:29 Annual Reviews AR080-Pref
xxii FIELDING
decline of many other diseases ranging from diphtheria and tetanus to hepatitis A and B (38).
In this century for the first time we eradicated a disease, smallpox, from the entire planet. The vanquishing of this scourge was a triumph of epidemiology and of worldwide cooperation among public health and other governmental or- ganizations. This success has emboldened public health leaders to target other diseases for near-term eradication: measles in the United States and polio world- wide. National Immunization Days have proved quite effective in developing countries, capped by polio vaccination of 119 million children in India in a single day (35).
Environmental and Occupational Health However, Michael Gochfeld and Bernard Goldstein remind us that environmen- tal health, almost synonymous with sanitation in the early part of the century, contributed to substantial reductions in vaccine preventable diseases long before vaccines were available (11). The environmental changes responsible for these reductions–improvement of food and water quality, better waste disposal, and reduction of crowding–reemerge as critical challenges to environmental health at century’s end, alongside the continuing challenge of control of industrial and agricultural chemicals (e.g. pesticides).
The field of occupational health was born and came of age in the twentieth century. As described by Mark Cullen, early in the century, dispersed reports of occupational disease in the medical literature, US Public Health Service and health departments interest in investigation and remediation of industrial sources of disease, and the enactment of workers’ compensation laws in vir- tually every state, together brought energy and new perspectives to occupa- tional health. Professional, industry, labor, and public attention were focused on both toxicological effects of work site exposures and unsafe working con- ditions. Emerging from periods of uneven progress and even regression are well-established occupational health professions, a federal system of health and safety regulations for the workplace, and occupational epidemiology.
Health Benefits and Health Care Costs PERSONAL HEALTH SERVICES Is personal health care a public good or a market good? As a nation our response in this century has been ambivalent. Medicare and Medicaid use broad-based tax revenue sources to provide health benefits for populations defined by age or limited categories of need. However, most Americans with benefits receive them from employer-sponsored plans (includ- ing government as the largest employer), and only small incremental efforts to extend coverage have been enacted at the national or state level over the past 35 years. The century ends with a paradox. We spend much more per capita
A nn
u. R
ev . P
ub li
c H
ea lt
h 19
99 .2
0: xi
ii -x
xx . D
ow nl
oa de
d fr
om w
w w
.a nn
ua lr
ev ie
w s.
or g
A cc
es s
pr ov
id ed
b y
37 .4
2. 10
7. 23
8 on
0 4/
08 /1
9. F
or p
er so
na l
us e
on ly
.
P1: KKK/SPD P2: APR/plb QC: KKK/anil T1: KKK
March 17, 1999 16:29 Annual Reviews AR080-Pref
TWENTIETH CENTURY PUBLIC HEALTH xxiii
than any other nation, but over 40 million Americans have no health benefits, and this number continues to grow (28).
One of the lessons of this century has been the difficulty in controlling health care expenditures. Increasing supplies of health care professionals, Federal and private investment in new technologies, and inflationary reimbursement systems helped to fuel the unprecedented rise in personal health care expenditures and pinched expenditures for core public health activities. Following the nation’s strong belief in the efficiency of markets, policy makers and health benefits purchasers decided to transform payment system incentives. The managed care premise was that if a fixed capitated amount was available to provide compre- hensive care, costs would decrease and system efficiency increase. Short-term effects were in the desired direction. However, the inherent disincentives for providing care and ethical conflict faced by providers suggest that further system evolution is likely.
Eli Ginzberg, however, foresees major changes in managed care, with physi- cians, not managers of HMOs, carrying primary responsibility for working with patients to determine treatment modalities. He anticipates a system of universal health insurance with access to “essential care,” which does not include high- cost hospitals or procedures and requires higher out-of-pocket costs for health care consumers (10).
Cost Increases and Benefits in Health In this century we went from spending very little, perhaps one or two percent of our gross domestic product, on personal health services to expending over 14%. Health care became our largest industry. At least some of the services associated with cost increases contributed to improved longevity (4), although the levels of contribution to improved health status and quality of life remain controversial. What is clear is that the unprecedented expansion in costs and utilization occurred without much discussion of what investments could yield the greatest health dividend. If public health’s mission is to fulfill society’s interest in assuring conditions in which people can be healthy (15), public health has yet to succeed in fostering a national debate on the relative return on investment to improve population health.
One origin of this failure is personal health services emergence as a sepa- rate, more powerful force that had a more resonating message for Americans than did public health. Public health was little involved in the establishment of obviously inflationary public and private insurance reimbursement principles that inexorably increased personal service costs much faster than the GDP for decades. And arguments advanced by some in public health–that one of the cost drivers, new technology, should only be incorporated when benefits were validated by improved health outcomes–were ineffectual.
A nn
u. R
ev . P
ub li
c H
ea lt
h 19
99 .2
0: xi
ii -x
xx . D
ow nl
oa de
d fr
om w
w w
.a nn
ua lr
ev ie
w s.
or g
A cc
es s
pr ov
id ed
b y
37 .4
2. 10
7. 23
8 on
0 4/
08 /1
9. F
or p
er so
na l
us e
on ly
.
P1: KKK/SPD P2: APR/plb QC: KKK/anil T1: KKK
March 17, 1999 16:29 Annual Reviews AR080-Pref
xxiv FIELDING
Since personal health came to be regarded as separate from public health, it became difficult to engage legislators in a rational policy process to weigh whether any of the funds for health care increases might yield more health if invested elsewhere. Alternatives range widely from expanding drug treatment or establishing a national home visiting program for new families, to expanding opportunities for physical activity at all ages, or reducing illiteracy and school dropout rates. Our future challenge is to convince policy makers that personal health care is only one determinant of health and that allocation decisions, whether in research, operational funding, or evaluation, should start with the objective of improved health for the entire population.
Public Health Infrastructure Another failure of public health has been an inability to retain all of its core functions under a single authority or even in multiple authorities with public health perspectives and expertise. In many states and municipalities, environ- mental health is not part of the public health agency. Air and water quality are often regulated and even their health effects monitored by other agencies, which may not have personnel trained in the human health effects of contamination. Public health agencies have, in general, not been effective in educating the public about their essential role in safeguarding and promoting the health of the entire population. Therefore, most public health agencies do not have strong constituencies to support their budget requests for core public health services.
The responsibility to assure adequate systems of personal health care led many public health agencies to develop systems of personal health care for those who could not otherwise afford care. These care systems, often centered around public health hospitals, have been creative in tapping local, state, and federal funding sources. However, funding is rarely sufficient to meet the full range of health care needs for those without other sources of care. The system is further jeopardized by enrollment of Medicaid eligible individuals—traditional users of public health care systems whose payments from Medicaid help subsidize care for the medically indigent—into private health plans that offer networks of primarily private providers.
Economics and Health The economic environment exerts strong influences on the public’s health. While the average standard of living has improved during the twentieth century, two other critical health determinants of current and future health have not. Poverty rates are increasing, particularly among children. It is well recognized that living in poverty negatively influences child health and development (1). The dispersion of income has also increased, so that, for example, the lower quintile income earners receive a smaller proportion of what the top quintile
A nn
u. R
ev . P
ub li
c H
ea lt
h 19
99 .2
0: xi
ii -x
xx . D
ow nl
oa de
d fr
om w
w w
.a nn
ua lr
ev ie
w s.
or g
A cc
es s
pr ov
id ed
b y
37 .4
2. 10
7. 23
8 on
0 4/
08 /1
9. F
or p
er so
na l
us e
on ly
.
P1: KKK/SPD P2: APR/plb QC: KKK/anil T1: KKK
March 17, 1999 16:29 Annual Reviews AR080-Pref
TWENTIETH CENTURY PUBLIC HEALTH xxv
earners receive than was the case earlier in our century. Income differentials in the United States exceed those of any other industrialized country (21).
Setting Health Targets An advance in public health is setting national health targets. Starting with the first set elaborated in 1979 inHealthy People: The Surgeon General’s Report on Health Promotion and Disease Prevention, the Federal government has coordi- nated an increasingly participatory process to enunciate national health goals. The sophistication of both the goals and process has evolved. From an initial focus on increasing longevity, the goals have been refined to target an increment in the quality and years of healthy life and eliminating health disparities among groups. Setting quantifiable and measurable targets for improvements based upon good science is the avowed and increasingly realistic goal for the objective setting process. Improving public health infrastructure and promoting healthy communities are recognized as essential underpinnings to achievement of these national goals (6).
Health Education and Health Promotion In this century there has been considerable evolution of paradigms for health education and health promotion, as chronicled by Larry Green (13). Health education became recognized as an important tool to change the risk factors associated with chronic diseases and injuries and to help control their medi- cal costs. However, the last quarter of the century saw the rise of the broader concept, health promotion, uniting attention to individual behaviors with the en- vironmental context that helps to shape behaviors and other health determinants.
The paradigm shift closer to the foundations of public health highlighted the importance of social health determinants and the need to work with com- munities. That social change strategies need to vary based on social, political, and cultural circumstances suggests to some that the process of participatory population-based planning may be more important in predicting effective so- cial change than use of a well-evaluated community intervention imported from another setting.
However, the process-oriented planning paradigm for health promotion calls into question the universality of evidence-based best practice for community interventions (34). Regardless of the guiding paradigm, evaluation of health promotion efforts requires multidisciplinary collaboration to assess changes in social, cultural, and political health determinants.
Health-Related Behaviors and Social Environments In this century we deepened our understanding of how many behaviors af- fect health, and we quantified their effect on populations. In addition to use of tobacco and other drugs, nutrition and physical activity have emerged as
A nn
u. R
ev . P
ub li
c H
ea lt
h 19
99 .2
0: xi
ii -x
xx . D
ow nl
oa de
d fr
om w
w w
.a nn
ua lr
ev ie
w s.
or g
A cc
es s
pr ov
id ed
b y
37 .4
2. 10
7. 23
8 on
0 4/
08 /1
9. F
or p
er so
na l
us e
on ly
.
P1: KKK/SPD P2: APR/plb QC: KKK/anil T1: KKK
March 17, 1999 16:29 Annual Reviews AR080-Pref
xxvi FIELDING
behaviors critical to public health. Abundant evidence exists that Americans consume too many calories, particularly calories from fat, and that the average level of physical activity is insufficient to achieve one’s health potential. Since the mid 1950s, dietary guidelines have recommended more consumption of grains, fruits, and vegetables, and less consumption of dairy products contain- ing fat, fatty desserts and snack foods. However, obesity has been increasing. More than 50% of the adult US population exceeds the recommended limits for body mass index (8), and the trends among children and adolescents presage future unhealthy effects (36).
In this century we also learned that social behaviors and social roles have strong influences on health. Social isolation, social status, and even marital sta- tus have major impacts not only on morbidity but also on mortality (24). These findings have profound implications for public health because improvements in population health must take account of, and try to influence, policies that can alter the social and economic environment.
Cultural Relevance Public health has learned that all interventions to promote health must be cul- turally relevant (16). For example, ethnic, racial, or culturally defined groups may have different perspectives on what constitutes obesity, on the relative attractiveness of different forms of contraception, or on what constitute safe food-handling procedures. Increasing demographic diversity, especially in ur- ban areas, precludes a one-size-fits-all approach to interventions.
Violence This is also the century in which we have come to consider violence as a public health problem (29). Homicide and suicide rank high in terms of potential years of life lost, while child abuse and domestic violence among adults have been shown to have long-term adverse consequences in addition to the short-term effects of the trauma. Social and economic conditions, including poverty and lack of opportunity, have been strongly associated with rate and pattern of violence, helping to explain high rates in certain minority groups. The ubiquity of handguns, the primary agent for deadly violence in the United States, has led to strongly championed but often unsuccessful efforts by public health coalitions to limit their availability and lethality.
GLOBAL TRENDS AFFECTING PUBLIC HEALTH IN THE UNITED STATES
Population Growth Population growth in this century has been unprecedented. In 1900, the popula- tion of our planet was 1.6 billion. By mid-century it had swelled to 2.5 billion,
A nn
u. R
ev . P
ub li
c H
ea lt
h 19
99 .2
0: xi
ii -x
xx . D
ow nl
oa de
d fr
om w
w w
.a nn
ua lr
ev ie
w s.
or g
A cc
es s
pr ov
id ed
b y
37 .4
2. 10
7. 23
8 on
0 4/
08 /1
9. F
or p
er so
na l
us e
on ly
.
P1: KKK/SPD P2: APR/plb QC: KKK/anil T1: KKK
March 17, 1999 16:29 Annual Reviews AR080-Pref
TWENTIETH CENTURY PUBLIC HEALTH xxvii
and by 2000 it will have grown to over 6 billion, a greater than 250% increase in one century (37, 17). The current 1.7% annual growth rate is the weighted average of a 0.6% increase in high-income countries and a 2.0% growth in- crease in medium and low-income countries. In the latter group of countries, just since mid-century average life expectancy at birth has increased by 23 years. Malthus aside, the rate of population growth and our absolute population are having serious effects on the quality of life of most of the world’s inhabitants.
Poorly controlled population growth has occurred despite great progress in developing effective contraception. Pills, IUDs, injectable and implantable hor- monal progestins, more effective barrier methods, and male and female steriliza- tion, can each effectively reduce the likelihood of pregnancy. These important public health advances have been largely obscured because mortality rates have fallen faster than fertility rates in most countries.
Globalization Globalization of commerce, GATT and NAFTA agreements that reduce na- tional trade barriers, and increased migration, all impact the quality of our en- vironment. At the close of the twentieth century, increasing emphasis is being placed on sustainability, with attention to both the adequacy of life-supporting resources and the adequacy to dispose of waste products (11). However, it is difficult to get developed countries to reduce their high rates of consumption of nonrenewable resources.
Environmental Destruction and Climate Change Desertification, deforestation of most tropical regions, and human-induced cli- mate changes endanger every nation. Increased burning of fossil fuels and re- duction of tropical rain forests, the most important carbon sink, have irreversible ecological and climatic effects. Another important sink for carbon, phytoplank- ton, is damaged by increased ultraviolet radiation due to depletion of the ozone layer, due to human made chemicals, particularly halocarbons. Adverse im- pacts on human health include neoplasia (e.g. malignant melanoma) and tissue degeneration (e.g. skin, eye lens) but also immunosuppression (18, 19).
Global climate change, population growth, and the consequences of eco- nomic development are inextricably linked. Solutions to these accelerating problems require global action, with public health teams joining with envi- ronmental organizations, engineers, and experts in convincing citizens and politicians that sacrifices today are needed to preserve the health of today’s youth and future generations.
Terrorism Another public health challenge that reflects more permeable national borders and our unique role in international affairs is terrorism. The United States emerged in the 1990s as the only superpower willing to act unilaterally if
A nn
u. R
ev . P
ub li
c H
ea lt
h 19
99 .2
0: xi
ii -x
xx . D
ow nl
oa de
d fr
om w
w w
.a nn
ua lr
ev ie
w s.
or g
A cc
es s
pr ov
id ed
b y
37 .4
2. 10
7. 23
8 on
0 4/
08 /1
9. F
or p
er so
na l
us e
on ly
.
P1: KKK/SPD P2: APR/plb QC: KKK/anil T1: KKK
March 17, 1999 16:29 Annual Reviews AR080-Pref
xxviii FIELDING
necessary to protect strategic national interests. More and more sophisticated political factions in other nations see the United States as their enemy and have vowed to destroy or at least disrupt our nation. A wide range of chemical, biological, and even nuclear agents are accessible to terrorists at a time when it is easy to smuggle substances into the United States. Developing a modulated, intelligent approach to threats or acts of terrorism deserves a coordinated effort by those in law enforcement, hazardous materials control, national security, and public health.
Looking Ahead The twentieth century ends as it began, with great opportunities to improve the public’s health by actions to improve environmental conditions that influence health and quality of life. The first public health revolution of the late nineteenth and early twentieth century focused on environmental interventions to reduce the toll of infectious agents. Our second revolution was the progress in methods and interventions to reduce the toll of chronic diseases and associated related behavioral risk factors. Looking ahead, we see the need for more intersectoral interventions to counter the human-made threats in our physical environment. Already these threats are contributing to a resurgence of famines in areas where they had previously been reduced or eliminated, to expansion of vectors due to climatic changes, to increases in allergic and other conditions, and to the alarming rise in malignant melanoma.
Among the most formidable challenges is to marry the biopsychosocial model of disease with the environmental social cause model to determine common final pathways. If public health is to be at the center of efforts to improve the health of our population, we need to better understand the pathways by which the underlying environmental and genetic factors produce intermediate risks and how these translate into health, disease, and quality of life.
The ethical dimension to public health must get more attention as we try to balance the rights and interests of individuals with those of communities and the larger society. Public health ethical issues are different than those of traditional biomedical ethics, which focus around the rights of individuals re- ceiving treatment or participating in a clinical trial. The public health questions needing an ethical compass range from whether to allow human cloning, to requiring mandatory HIV reporting, to allowing managed care companies to constrain the amount of care provided and the extent to which resources should be preferentially re-directed at reducing systematic disparities in health access across population subgroups.
Peering forward, we see a pace of technological innovation that is outstripping our ability to formulate an ethical framework for evaluating them. Cloning, test-tube babies, limb regeneration, arresting or slowing the aging process,
A nn
u. R
ev . P
ub li
c H
ea lt
h 19
99 .2
0: xi
ii -x
xx . D
ow nl
oa de
d fr
om w
w w
.a nn
ua lr
ev ie
w s.
or g
A cc
es s
pr ov
id ed
b y
37 .4
2. 10
7. 23
8 on
0 4/
08 /1
9. F
or p
er so
na l
us e
on ly
.
P1: KKK/SPD P2: APR/plb QC: KKK/anil T1: KKK
March 17, 1999 16:29 Annual Reviews AR080-Pref
TWENTIETH CENTURY PUBLIC HEALTH xxix
growing organs from stem cells, changing genes in test-tubes or in utero to obtain children with desired characteristics—all of these marvels have been accomplished in humans or other animals. Where are limits to be set? Who should set them? Under what circumstances, if any, should these techniques be considered to advance collective social good versus individual good? How much public investment should these technological advances receive compared to other investments to improve the public’s health? These are grist for the mill of the twenty-first century.
Visit the Annual Reviews home pageat http://www.AnnualReviews.org
Literature Cited
1. Aber JL, Bennett NG, Conley DC, Li J. 1997. The effects of poverty on child health and development.Annu. Rev. Public Health 18:463–83
2. Anon. 1997. Births, marriages, divorces, and deaths for January 1997.Mon. Vital Stat. Rep.46(1):1–18
3. Breslow L, Johnson M. 1993. California’s Proposition 99 on tobacco and its impact. Annu. Rev. Public Health14:585–604
4. Bunker JP, Frazier HS, Mosteller F. 1995. The role of medical care in determining health: creating an inventory of benefits. In Society and Health, ed. BC Amick, S Levine, A Tarlov, DC Walsh, pp. 305–41. New York: Oxford Univ. Press
5. DeJong W, Hingson R. 1998. Strategies to reduce driving under the influence of al- cohol. Annu. Rev. Public Health19:359– 78
6. Department of Health and Human Ser- vices. 1998.Healthy People, 2010 Objec- tives, Draft for Public Comment, Septem- ber. Washington, DC
7. Fielding JE, Husten CG, Eriksen M. 1998. Tobacco: health effects and control. In Public Health & Preventive Medicine, ed. RB Wallace, 1:817–45. Stamford, CT: Ap- pleton & Lange. 14th ed.
8. Flegal KM, Carroll MD, Kuczmarsky RJ, Johnson CL. 1998. Overweight and obesity in US: prevalence and trends, 1960–94.Int. J. Obesity22:39–47
9. Flora JA, Maibach EW, Maccoby N. 1989. The role of media across four levels of health promotion intervention.Annu. Rev. Public Health10:181–201
10. Ginsberg E. 1999. US health care: a look ahead to 2025.Annu. Rev. Pub. Health20: 55–66
11. Gochfeld M, Goldstein BD. 1999. Lessons in environmental health in the twentieth century.Annu. Rev. Public Health20:35– 53
12. Graham JD, Corso PS, Morris JM, Segui- Gomez M, Weinstein MC. 1998. Evaluat- ing the cost-effectiveness of clinical and public health measures.Annu. Rev. Public Health19:125–52
13. Green LW. 1999. Health education’s con- tribution to public health in the twentieth century: a glimpse through health promo- tion’s rear-view mirror.Annu. Rev. Public Health20:67–88
14. Guralnick JM, Fried LP, Salive M. 1996. Disability as a public health outcome in the aging population.Annu. Rev. Public Health 17:25–46
15. Institute of Medicine, Committee on the Future of Public Health. 1988.The Future of Public Health. Washington DC: Natl. Acad.
16. Kerner JF, Dusenbury L, Mandelblatt JS. 1993. Poverty and cultural diversity: chal- lenges for health promotion among the medically underserved.Annu. Rev. Public Health14:355–77
17. Last JM. 1998. Human health in a chang- ing world. In Public Health & Preventive Medicine, ed. JM Last, RB Wallace, p. 781. Norwalk, CT: Appleton & Lange. 14th ed.
18. Last JM. 1998. Human health in a chang- ing world. In Public Health & Preventive Medicine, ed. JM Last, RB Wallace p. 788. Norwalk, CT: Appleton & Lange. 14th ed.
19. Last JM. 1993. Global change: ozone de- pletion, greenhouse warming and public health.Annu. Rev. Public Health14:115– 36
20. Lave LB, Joshi SV. 1996. Benefit-cost
A nn
u. R
ev . P
ub li
c H
ea lt
h 19
99 .2
0: xi
ii -x
xx . D
ow nl
oa de
d fr
om w
w w
.a nn
ua lr
ev ie
w s.
or g
A cc
es s
pr ov
id ed
b y
37 .4
2. 10
7. 23
8 on
0 4/
08 /1
9. F
or p
er so
na l
us e
on ly
.
P1: KKK/SPD P2: APR/plb QC: KKK/anil T1: KKK
March 17, 1999 16:29 Annual Reviews AR080-Pref
xxx FIELDING
analysis in public health.Annu. Rev. Public Health17:203–19
21. Lee PR, Paxman D. 1997. Reinventing public health.Annu. Rev. Public Health18: 1–3
22. Little RE. 1998. Public health in Central and Eastern Europe and the role of environ- mental pollution.Annu. Rev. Public Health 19:153–72
23. Maibach E, Holgrave DR. 1995. Advances in public health communication.Annu. Rev. Public Health16:219–38
24. Marmot MG. 1994. Social differentials in health within and between populations. 123(4):197–216
25. Morgenstern H. 1995. Ecologic studies in epidemiology: concepts, principles and methods.Annu. Rev. Public Health16:61– 81
26. Mosher JF, Jernigan DH. 1989. New direc- tions in alcohol policy.Annu. Rev. Public Health10:245–79
27. Mosteller F, Colditz G. 1996. Understand- ing research synthesis (meta-analysis). Annu. Rev. Public Health17:1–23
28. Moyer G. 1998. The Uninsured and the In- sured in the March 1997Current Popula- tion Survey. Dep. Health Hum. Serv. Wash- ington, DC
29. Rosenberg ML, Mercy JA, Annest JL. 1993. The problem of violence in the United States and globally. InPublic Health & Preventive Medicine, ed. RB Wallace, BN Doebbeling. pp. 1223–26. Norwalk, CT: Appleton & Lange. 13th ed.
30. Rowe JW, Kahn RL. 1998.Successful Ag- ing. New York: Patheon Books
31. Schwartz S, Susser E, Susser M. 1999. A future for epidemiology?Annu. Rev. Pub- lic Health 20:15–33
32. Surgeon General’s Report on Smoking and Health. 1964. InCumulative Index of
Health Consequences of Smoking, a report of the Surgeon General: 1964–1982, Vol. 1. Arlington, VA: In. Resourc.
33. The Sixth Report of the Joint Na- tional Committee on Prevention, Detec- tion, Evaluation and Treatment of High Blood Pressure. 1997.Archives Int. Med. 157(21):2413–46
34. Sorensen G, Emmons K, Hunt MK, John- ston D. 1998. Implications of results of community intervention trials.Annu. Rev. Public Health19:379–416
35. Sutter RW, Cochi SL. 1998. Poliomyelitis. In Public Health & Preventive Medicine, ed. RB Wallace, p. 123. Stamford, CT: Ap- pleton & Lange. 14th ed.
36. Troiano RP, Flegal KM. 1998. Overweight children and adolescents: description, epi- demiology, and demographics.J. Pedi- atrics 101:497–504 (Suppl.)
37. Tyler CW Jr, Warren CW. 1998. Public health and population. InPublic Health & Preventive Medicine, ed. JM Last, RB Wallace, p. 54. Norwalk, CT: Appleton & Lange. 14th ed.
38. US Preventive Services Task Force. 1996. Guide to Clinical Preventive Services. Bal- timore, MD: Williams & Wilkins
39. Ware JE Jr. 1995. The status of health as- sessment 1994.Annu. Rev. Public Health 16:327–54
40. Woolf SH, DiGuiseppi CG, Atkins D, Kamerow DB. 1996. Developing evidence- based clinical practice guidelines.Annu. Rev. Public Health17:511–38
41. World Health Organization. 1996, ed. CJL Murray, AD Lopez.The Global Burden of Disease. Geneva, Switzerland
42. Yen IH, Syme SL, The social environment and health: a discussion of the epidemio- logic literature.Annu. Rev. Public Health 20:287–308
A nn
u. R
ev . P
ub li
c H
ea lt
h 19
99 .2
0: xi
ii -x
xx . D
ow nl
oa de
d fr
om w
w w
.a nn
ua lr
ev ie
w s.
or g
A cc
es s
pr ov
id ed
b y
37 .4
2. 10
7. 23
8 on
0 4/
08 /1
9. F
or p
er so
na l
us e
on ly
.
Annual Review of Public Health Volume 20, 1999
CONTENTS PUBLIC HEALTH IN THE TWENTIETH CENTURY: Advances and Challenges, Jonathan E. Fielding xiii Personal Reflections on Occupational Health in the Twentieth Century: Spiraling to the Future, Mark R. Cullen
1
A Future for Epidemiology?, S. Schwartz, E. Susser, M. Susser 15 Lessons in Environmental Health in the Twentieth Century, Michael Gochfeld, Bernard D. Goldstein
35
US Health Care: a Look Ahead to 2025, Eli Ginzberg 55
What Have We Learned About Public Health in the Twentieth Century: A Glimpse Through Health Promotion's Rearview Mirror, L. W. Green
67
Understanding Changing Risk Factor Associations with Increasing Age in Adults, G. A. Kaplan, M. N. Haan, R. B. Wallace
89
Advances in Clinical Trials in the Twentieth Century, Lloyd D. Fisher 109
Methods for Analyzing Health Care Utilization and Costs, P. Diehr, D. Yanez, A. Ash, M. Hornbrook, D. Y. Lin
125
Time-Dependent Covariates in the Cox Proportional Hazards Regression Model, Lloyd D. Fisher, D. Y. Lin
145
Lessons from 12 Years of Comparative Risk Projects, Ken Jones, Heidi Klein
159
Unexplained Increases in Cancer Incidence in the United States from 1975 to 1994: Possible Sentinel Health Indicators?, Gregg E. Dinse, David M. Umbach, Annie J. Sasco, David G. Hoel, Devra L. Davis
173
Eradication of Vaccine-Preventable Diseases, A. Hinman 211 Immunization Registries in the United States: Implications for the Practice of Public Health in a Changing Health Care System, David Wood, Kristin N. Saarlas, Moira Inkelas, Bela T. Matyas
231
Teen Pregnancy Prevention: Do Any Programs Work?, Josefina J. Card 257
The Social Environment and Health: A Discussion of the Epidemiologic Literature, I. H. Yen, S. L. Syme
287
Health Status Assessment Methods for Adults: Past Accomplishments and Future Challenges, Colleen A. McHorney
309
Patient Outcomes Research Teams: Contribution to Outcomes and Effectiveness Research, Deborah Freund, Judith Lave, Carolyn Clancy, Gillian Hawker, Victor Hasselblad, Robert Keller, Ellen Schneiter, James Wright
337
Pharmacy Benefit Management Companies: Dimensions of Performance, Helene L. Lipton, David H. Kreling, Ted Collins, Karen C. Hertz
361
The Key to the Door: Medicaid's Role in Improving Health Care for Women and Children, Diane Rowland, Alina Salganicoff, Patricia Seliger Keenan
403
A nn
u. R
ev . P
ub li
c H
ea lt
h 19
99 .2
0: xi
ii -x
xx . D
ow nl
oa de
d fr
om w
w w
.a nn
ua lr
ev ie
w s.
or g
A cc
es s
pr ov
id ed
b y
37 .4
2. 10
7. 23
8 on
0 4/
08 /1
9. F
or p
er so
na l
us e
on ly
.
