While it is undoubtedly true that a biomedical perspective dominated public health in the first half of the twentieth century, there has emerged, largely since World War II, a social science perspective in public health. This perspective has developed in departments of social and community medicine in Europe and in schools of public health in the United States, and it is reflected in the growth of the behavioral and social sciences in the curricula for public health professional and research degrees. This perspective is also evident in the establishment of departments of social and behavioral sciences in universities.
Many social and behavioral science disciplines are relevant to the understanding and articulation of the mission of public health. It would be impossible to document here all the various discipline areas; these include disciplines as diverse as psychology, economics, history, and anthropology. The focus here will be on those disciplines that most directly attempt to describe, understand, predict, and change the public's health.
SOCIAL AND BEHAVIORAL SCIENCES LITERATURE
A considerable literature on individual behavior and public health has developed in the second half of the twentieth century. The general failure of public health to pick up and nurture the more macro social science perspectives to the same degree has limited the full potential of the impact of the social and behavioral sciences on public health, particularly because the historical roots of public health in the latter half of the nineteenth century included a strong social structural viewpoint. Since that time, the theoretical development of economics, political science, sociology, and anthropology has accelerated, but it was often not brought to bear on contemporary public health issues because these issues were often defined in terms of the characteristics of individuals rather than as characteristics of social structure. The argument is, then, that public health picked up the wrong end of the social science stickhe individual (micro) end rather than the sociocultural (macro) end. This assertion is supported by any perusal of public health journals or literature on social and behavioral science in public health in the second half of the twentieth century. Nonetheless, as the end of the twentieth century in public health witnessed increasing concern with social concepts such as social inequity, inequality, and community interventions, the disciplines of sociology, anthropology, economics, and political science had a more important role in public health, for the determinants of health were being defined in terms of a social and behavioral perspective. For example, many individual behaviors were recognized as risk factors for poor health, but were also seen as embedded in a wider social context. In addition, a social sciencenformed healthful public policy was seen by many as a key to the development of public health strategies to improve health.
THE SCIENTIFIC DISCIPLINES AND PUBLIC HEALTH
As noted previously, there are several social and behavioral science disciplines applied to public health. What follows is a brief summary of each of the key disciplines, with attention given to the theory and work of each discipline relevant to public health. In some of the social science disciplines there are large subdisciplinary areas devoted to medicine. For example, there are large subdisciplinary fields such as history of medicine, medical sociology, medical anthropology, health psychology, and medical geography. Most of these subdisciplines have university departments, dedicated journals, and professional organizations. However, most of these subdisciplines are concerned with medicine in the very broadest interpretation, including health promotion, clinical care, disease prevention, and biomedical research. Only a part of a subdiscipline such as medical sociology is concerned with public health. Similarly, most of the subdiscipline of history of medicine is concerned with the development and evolution of clinical medicine rather than public health. Thus, the interpretation of the role of the social and behavioral sciences in public health is very much tied to one's definition of public health.
THE SOCIAL AND BEHAVIORAL SCIENCE DISCIPLINES
The social sciences are concerned with the study of human society and with the relationship of individuals in, and to, society. The chief academic disciplines of the social sciences are anthropology, economics, history, political science, and sociology. The behavioral sciences, particularly psychology, are concerned with the study of the actions of humans and animals. The key effort of the behavioral sciences is to understand, predict, and influence behavior. The chief academic disciplines of the behavioral sciences are anthropology, psychology, and sociology, with the distinction between social and behavioral science often blurred when these disciplines are applied in public health research and practice, particularly in schools of public health and governmental agencies. Many, if not most, public health approaches are problem focused and lead to a multidiscipline solution encompassing several social and behavioral science disciplines and combinations of them (such as social psychology), in addition to other public health disciplines such as epidemiology and biostatistics.
Anthropology. Anthropology is a broad social science concerned with the study of humans from a social, biological and cultural perspective. Historically it is a Western-based social science with roots in Europe and North America. It includes two broad areas of physical and sociocultural anthropology; both are relevant to public health. Physical anthropology divides into two areas, one related to tracing human evolution and the study of primates, and the other concerned with contemporary human characteristics stemming from the mixture of genetic adaptations and culture. Medical anthropologists with this perspective are often concerned with the relationships between culture, illness, health, and nutrition. Sociocultural anthropology is concerned with broad aspects of the adaptation of humans to their cultureswith social organization, language, ethnographic details, and, in general, the understanding of culturally mitigated patterns of behavior. In recent decades this perspective has taken a more ecologically focused view of the human species. From a public health perspective, this approach to anthropology is probably most salient in terms of the methodological approaches used by anthropologists. They have a critical concern with understanding communities through participant observation. Indeed, participation is probably the key concept linking modern-day anthropological approaches to twentieth-century concepts of public health community interventions. Although the methodology of rapport-based structured interviews and observation is a highly developed methodology among anthropologists, it has had limited application in public health. More recent efforts in public health to address issues of inequity at the community level have created more attention to anthropological approaches.
Economics. Economics is perhaps the oldest of the social sciences, with its concern with wealth and poverty, trade and industry. However, current economic thinking generally dates from the last three centuries and is associated with the great names in economic thinking, such as Adam Smith, Robert Malthus, David Ricardo, John Stuart Mill, and Karl Marx. Present-day economics is an advanced study of production, employment, exchange, and consumption driven by sophisticated mathematical models. Basically, the field breaks into two distinctive areas: microeconomics and macroeconomics. Microeconomics is largely concerned with issues such as competitive markets, wage rates, and profit margins. Macroeconomics deals with broader issues, such as national income, employment, and economic systems. The relationship between economics and health is obvious because in developed countries the percentage of gross national product consumed by the health care industry is significant, generally ranging from 5 to 15 percent of the gross national product. In the poorer countries, the cost of disease to the overall economy can prohibit the sound economic development of the country. In recent years there has been a concern with both the global economic burden of disease as well as with investment in health. That poverty is highly related to poor public health is a widely accepted tenet of modernday thinking in public health. However, economic systems ranging from free enterprise through liberal socialism and communism offer quite differing alternatives to the reduction of poverty and the distribution of economic resources.
Psychology. Psychology is probably the most common disciplinary background found in the application of the social and behavioral sciences to public health. Modern psychology is a large field that encompasses physiological psychology, concerned with the nervous and circulatory systems, as well as social psychology, and concerned with the behavior of individuals as influenced by social stimuli. In general, psychology is concerned with the relationship of living organisms to their environment. In addition to studies focused on physiological mechanisms, psychology is concerned with the broad area of human cognition, including learning, memory, and concept formation. The subfield of abnormal psychology is concerned with mental disorders, ranging from psychoses to neuroses. The subfield of clinical psychology offers direct patient-care mechanisms to treat mental problems in individuals. Thus the application of psychological approaches to health is quite apparent.
However, the most salient branch of psychology for public health practice, and particularly for the task of understanding the determinants of health, is probably social psychology. A major focus of social psychology is on attitudes, opinions, and behaviors. Thus, there is an emphasis on understanding how groups and individuals interact with one another. The degree to which many interactions are easy or difficult can play a major role in determining the stability of groups and individuals. Therefore, broad concepts such as stress, social cohesion, peer influence, civic trust, and others derive strong theoretical and research support from social psychology.
Sociology. Sociology is perhaps the broadest of the social science fields applied to public health. It is also characterized by being eclectic in its borrowing from the other social sciences. Thus, sociology is also concerned with organizations, economics, and political issues, as well as individual behaviors in relation to the broader social milieu. A key concept in sociology, however, is an emphasis on society rather than the individual. The individual is viewed as an actor within a larger social process. This distinguishes the field from psychology. Thus the emphasis is on units of analysis at the collective level such as the family, the group, the neighborhood, the city, the organization, the state, and the world. Sociology is concerned with how the social fabric or social structure is maintained, and how social processes, such as conflict and resolution, relate to the maintenance and change of social structures. A sociologist studies processes that create, maintain, and sustain a social system, such as a health care system in a country. The scientific component of this study would be the concern with the processes regulating and shaping the health care system. Sociology assumes that social structure and social processes are very complex.
THE SOCIAL AND BEHAVIORAL SCIENCES WORKING TOGETHER
Many social and behavioral scientists who work in public health have strong, disciplinary-based, undergraduate and graduate training in one of the social sciences. However, the practice of academic and governmental public health involves disciplinary bases that are seldom as narrow as they would be in traditional, university-based academic departments. Indeed, in many government institutions of public health such discipline-trained social scientists may be simply referred to as health scientists or even as social epidemiologists. Public health practice is largely problem-focused, and whatever disciplinary base is appropriate to the problem will be used. Thus, it would not be uncommon for a person trained as a psychologist to be involved with a program addressed at community change or for an anthropologist to be involved with individual behavioral change. Nonetheless, all of the social and behavioral sciences share a commonality in approach to public health that differs from that of the biomedical approach. Disease is usually seen as a distal outcome, the focus being on those social and behavioral processes that prevent and reduce disease in people. Generally, the social sciences take a view that health and sickness are only one part of people's lifestyle.
The social and behavioral sciences have varied and broad-based methodologies. Discussions of methodological approaches to knowledge attainment are at the heart of many discipline-based discussions. Perhaps the greatest ongoing debate is that over the role of qualitative and quantitative approaches to understanding. Many researchers and practitioners in public health consider data to be the sine qua non of public health. Often data are perceived as being quantitative and numerate. The social and behavioral sciences take a much broader view of what data is. Data can be personal accounts and stories as well as statistical presentations. Nonetheless, the rigor underpinning the appropriate collection of good data applies to both the quantitative and qualitative approaches. There is a strong appreciation that many quasiscientific cognitive ideas, such as race, poverty, or trust, cannot simply be quantified and understood numerically, yet still play a key role in determining health outcomes.
THE DETERMINANTS OF HEALTH
In discussing the determinants of health it is useful to distinguish between the health of individuals and populations. The determinants of health for any individual relate highly to the unique characteristics of that individual. In the first instance, these characteristics are highly determined by biologyhe gender, age, and genetic background of the individual. These characteristics play a primary determining role and are usually not modifiable. For example, it is obvious that a man cannot die from ovarian cancer, or a woman from testicular cancer. Generally, only an older person will suffer from Alzheimer's disease; only a person with a genetic deficit will suffer from Down syndrome. Medical science and public health can do little to change these powerful determinants of health in the individual. However, it is also anticipated that most individuals born in the Western world of the twenty-first century are biologically equipped to have a life expectancy of some seventy to eighty years.
The health of populations is a different concept from that of the health of individuals, and the determinants of the health of populations may be conceptualized very broadly. The following is just a short list of some of the hypothesized determinants of population health: health care services, sewers and drains, potable water, sanitation, adequate nutrition, shelter, transportation networks, supportive social environments, healthful public policy, stable child-rearing environments, healthful work environments, and peace and tranquility. What is apparent in such a broad list is that most of the hypothesized determinants are outside of the traditional medical care sector of clinics and hospitals. Many determinants of population health are determined by human conditions at the broadest level of political interaction, such as the protection from the ravages of poverty, war, and refugee status. Most important, the individual has relatively little direct control over these determinants. Even in those arenas where the individual believes he or she has control, such as in pursuit of education, occupation, and income through the life span, the reality remains that access to education, occupation, and income is socially determined.
People suffer disease and illness due to social processes that are only remotely related to personal health care. As public health moves away from personal health care as the major determinant of public health to a position where it is merely one of many determinants of public health, the role of the social and behavioral sciences becomes more important in understanding population health. The World Health Organization European Office lists ten social determinants of health that are supported by strong research evidence:(1) the social gradient (people's relative social and economic status and circumstances strongly affect their health throughout life); (2) stress (stress harms health); (3) early life (the effects of early development last a lifetime); (4) social exclusion (social exclusion creates misery and costs lives); (5) work (stress in the workplace increases the risk of disease); (6) unemployment (job security increases health, well-being, and job satisfaction); (7) social support (friendship, good social relations, and strong supportive networks improve health at home, at work, and in the community); (8) addiction (individuals turn to alcohol, drugs, and tobacco and suffer from their use, but use is influenced by the wider social setting); (9) food (healthful food is a political issue); and (10) transport (healthful transport means reducing driving and encouraging more walking and cycling, backed up by better public transport).
THE ROLE OF THE SOCIAL AND BEHAVIORAL SCIENCES
In contributing to the understanding of the determinants of health, there are two chief challenges for the social and behavioral sciences. The first is to continue to build in greater depth the knowledge and evidence base for the role of socioeconomic factors in health. The second is to develop appropriate best practices for addressing the role of socioeconomic factors in order to improve the health of the public. These are related challenges, but the first is perhaps more of a challenge for the academic world, and the second for the world of public health practice. Despite the enormous complexity inherent in these challenges, there is a large and growing literature to address both of them. There is a very large literature in Western languages addressing the role of socioeconomic status (SES) and its relationship to mortality and morbidity in infants, children, adolescents, and young and old adults. In general the available evidence is more extensive for working-aged adults, where multiple studies from many countries show powerful evidence linking low SES to increased chronic disease mortality and morbidity among males and a consistent gradient of the association between levels of SES and levels of health.
Conceptually, this is a very complex and extensive area for research because of the large number of variable combinations in any research approach. Thus, if one takes SES as the determinant of interest, it needs to be studied for its impact on every age group, gender, and ethnic or racial group, in relation to many possible outcomes, including chronic disease morbidity and mortality and risk factors for each disease. The resulting matrix of variable combinations is indeed exceedingly complex. Even though research has looked at many of the relationships possible, they clearly have not all been explored in the detail to bring surety in conclusions. That is why the research challenge is so greathere is much more basic research that needs to be undertaken to fully understand the complexities associated with the social determinants of health.
The second challenge is even more critical and is at the heart of public health ideology. Public health is predicated on the idea that one wants to take action to prevent or control disease; at the same time public health is also concerned with promoting health and preventing disease at the population level. Thus, the ideal strategies for public health practice call for action at the population level. It is, however, one thing to understand the complex mechanisms that link social determinants to health, it is quite another to try and alter them. At first glance it would appear that the solution is simple. If poverty causes poor health, then elimination of poverty should increase the overall population health. Few could disagree; nonetheless poverty itself is the result of many contributing factors. Furthermore, many in public health might well argue that large-scale programs to eliminate poverty, such as equal income distribution policies, are well beyond the scope of public health practice and carry with them political risks and an adverse impact on economic aspects of a society.
One social-science approach is to look at the scope and characteristics of the problem and then determine what is a feasible course of action to maximize benefits within the restraints of a given social systemn approach that is based on the realities within any given country's sociopolitical system. Such an approach recognizes the diversity and variability both within and between sovereign countries, but at the same time recognizes the global interdependence of all countries. Nonetheless, when public health researchers and agencies within countries have addressed the socioeconomic determinants of health from the standpoint of interventions, several common themes emerge.
First, there is the recognition of the need to pursue macro-level economic and social policies that create investment in the physical and social determinants of health. In general, this means an effort to address broad issues to improve health care infrastructure, education, transportation systems, and housing, as well as participation in a just society. It also means addressing inequities and issues of poverty. Such approaches are made explicit in documents such as Healthy People 2010.
Second, there is a strong attention to the community as the setting for public health interventions. That is, the everyday living and working conditions must be improved, particularly when these are accompanied by poverty and the plight of disadvantaged groups. Increasing control of the environment by those within it is a strong component of a participation-based intervention approach.
Third, behavioral risk factors remain a critical component of interventions to address the social determinants of health. Although the social setting and milieu may produce many barriers to behavior change, there remains considerable latitude at the individual level for change. Particularly in the addictive behaviors, the role of the individual remains powerful and inescapable. Evidence-based interventions need to combine the knowledge of the social and behavioral science disciplines to address the complexity of behavioral change.
Fourth, the personal health care system is seen as a critical component of the determinants of health and is the system closest to the professions of most of those who labor in the field of public health. The critical issue for the personal health care system is to address the inequities in access to quality care. These inequities stem from many determinants, including poverty and prejudice. Sociodemographic factors such as geography and urbanization also play a key role. Adequate and equitable distribution of health care resources remains a challenge for the entire globe, as does humane treatment and attention to social and psychological factors in the overall well-being of patients and families seen in these settings.
DAVID V. MCQUEEN
(SEE ALSO: Cultural Anthropology; Cultural Factors; Diffusion Theory; Economics of Health; Environmental Determinants of Health; Ethnicity and Health; Health Promotion and Education; Inequalities in Health; Lifestyle; Medical Sociology; Psychology; Psychology, Health; Social Class; Social Determinants; Sociology in Public Health)
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