BEHAVIOR, HEALTH-RELATED

Health-related behavior is one of the most important elements in people's health and well-being. Its importance has grown as sanitation has improved and medicine has advanced. Diseases that were once incurable or fatal can now be prevented or successfully treated, and health-related behavior has become an important component of public health. The improvement of health-related behaviors is, therefore, central to public health activities.

Behavioral factors play a role in each of the twelve leading causes of death, including chronic diseases such as heart disease, cancer, and stroke, which are the major causes of death in the United States and other developed countries. The most common behavioral contributors to mortality, or death, in 1990 included the use of alcohol, tobacco, firearms, and motor vehicles; diet and activity patterns; sexual behavior; and illicit use of drugs. Behaviors such as these are thought to contribute to almost half of the deaths in the United States, and, according to J. McGinnis and W. Foege (1993), they were responsible for nearly 1 million deaths in the United States in the year of 1992 alone. The social and economic costs related to these behaviors can all be greatly reduced by changes in individuals' behaviors.

The last two decades of the twentieth century saw a rising interest in preventing disability and death through changes in health-related behaviors, particularly changes in lifestyle habits and participation in screening programs. Much of this interest was stimulated by the change in disease patterns from infectious to chronic diseases as leading causes of death, combined with the aging of the population, rapidly escalating health care costs, and data linking individual behaviors to increased risk of morbidity and mortality. The AIDS (acquired immunodeficiency syndrome) epidemic also contributed.

Although there is more information about what constitutes healthy behavior and risk factors than ever before, this information has not always led to healthier behaviors. There have been some positive changes, however. Between 1988 and 1994, the average daily intake of dietary fat in the United States dropped from 36 percent to 34 percent of total calories; seat belt use increased from 42 percent to 67 percent; and the number of women over the age of forty who had breast exams and mammograms doubled. Cigarette smoking has decreased among men by as much as 50 percent in some countries. Unfortunately, during this same period, the number of obese adults rose, sexual activity among adolescents increased, more teenage girls began smoking, and the incidence of HIV (human immunodeficiency virus)/AIDS reached epidemic proportions.

DEFINITIONS OF HEALTH BEHAVIOR

There are many questions about health-related behavior, or health behavior, that are not yet well understood. Therefore, both public health workers and scientific researchers continue to attempt to understand the nature and causes of many different health behaviors. Health behavior encompasses a large field of study that cuts across various fields, including psychology, education, sociology, public health, epidemiology, and anthropology.

In the broadest sense, health behavior refers to the actions of individuals, groups, and organizations, as well as the determinants, correlates, and consequences, of these actions—which include social change, policy development and implementation, improved coping skills, and enhanced quality of life. This is similar to the working definition of health behavior that David Gochman proposed, which includes not only observable, overt actions but also the mental events and emotional states that can be reported and measured. Gochman defined health behavior as "those personal attributes such as beliefs, expectations, motives, values, perceptions, and other cognitive elements; personality characteristics, including affective and emotional states and traits; and overt behavior patterns, actions, and habits that relate to health maintenance, to health restoration, and to health improvement." Interestingly, this definition emphasizes the actions and the health of individuals. A public health perspective, in contrast, is concerned with individuals as part of a larger community. These perspectives are interrelated, as the behaviors of individuals determine many of the social conditions that affect all people's health.

Gochman's definition is consistent with the definitions of specific categories of overt health behavior proposed by S. Kasl and S. Cobb. In two seminal 1966 articles, Kasl and Cobb define three categories of health behavior:

• Preventive health behavior involves any activity undertaken by individuals who believe themselves to be healthy for the purpose of preventing or detecting illness in a asymptomatic state. This can include self-protective behavior, which is an action intended to confer protection from potential harm, such as wearing a helmet when riding a bicycle, using seat belts, or wearing a condom during sexual activity. Self-protective behavior is also known as cautious behavior.
• Illness behavior is any activity undertaken by individuals who perceive themselves to be ill for the purpose of defining their state of health, and discovering a suitable remedy.
• Sick-role behavior involves any activity undertaken by those who consider themselves to be ill for the purpose of getting well. It includes receiving treatment from medical providers, generally involves a whole range of dependent behaviors, and leads to some degree of exemption from one's usual responsibilities.

These classic definitions have stood the test of time, and continue to be used by students and public health workers alike. However, the lines between these three categories have blurred somewhat over time, and there are also several categories of behavior that warrant specific definitions.

Behavior versus Lifestyle. Health behavior can be something that is done once, or something that is done periodically—like getting immunizations or a flu shot. It can also be something that one does only to oneself, such as putting on sunscreen, or a behavior that affects others, like putting up a shade cover so that children at a playground are protected from the sun. Other health behaviors are actions that are performed over a long period of time, such as eating a healthful diet, getting regular physical activity, and avoiding tobacco use. It is these latter types of behaviors, which are sustained patters of complex behavior, that are called "lifestyle" behaviors. A composite of various healthful behaviors is often referred to as "healthy lifestyle." However, most people do not practice either healthful or risky behaviors with complete consistency—someone might get regular, health-promoting exercise several times a week but be a cigarette smoker who seldom brushes his or her teeth; or someone might quit smoking, only to begin eating chocolate as a substitute. In the ideal, the person who practices a variety of behaviors in a health-enhancing manner can be described as living a healthy lifestyle. More realistically, though, many people practice some, but not all, lifestyle behaviors in a consistently healthful manner.

Health-Related and Health-Directed Behavior. Health-related behavior is any action that is related to disease prevention, health maintenance, health improvement, or the restoration of health. This type of behavior can be either voluntary or involuntary, and can be undertaken explicitly for health purposes, as a matter of habit, or to comply with a law or requirement. For example, a child who runs 800 meters in a physical education class is performing a health-related behavior, but only because the teacher requires it to get a passing grade. In contrast, an adult who exercises to reduce the risk of heart disease is engaging in that behavior for the express purpose of restoring, maintaining, or improving his or her health. This type of action is called "health-directed behavior." Sometimes these two types of health behavior coexist—a toddler buckled into a safety seat is participating in health-related behavior, but for the parent this is a health-directed behavior.

Self-Care Behavior. Self-care behavior involves taking actions to improve or preserve one's health. Self-care is often thought of in terms as prevention or self-treatment of definable health problems or conditions, but it can also include primary prevention in the absence of any symptoms. Self-care includes the actions taken to treat symptoms before (or instead of) seeking professional medical attention, such as eating chicken soup, drinking liquids, or taking over-the-counter medications for cold or flu-like symptoms. It also includes treating minor injuries such as bruises, scrapes, and twisted ankles when a person does not think a health care professional is needed. Self-care is also a continuum whereby a patient may complete home treatments such as changing a bandage or wound dressing, doing rehabilitation exercises, or avoiding foods that inflame an allergic reaction. The use of alternative and complementary medical treatments, without medical supervision, is also self-care behavior. An important feature of self-care behavior is that it involves active participation in the health care process.

Health Care Utilization Behavior. Health care utilization is the use of health services, whether it be clinical public health services or the services of medical care professionals. Health care utilization behavior is a continuum that ranges from using preventive services, such as getting immunizations or early detection and screening tests, to elective surgery or involuntary hospitalization after an injury. Health care utilization is influenced by many different factors, and therefore the study of utilization behavior includes examining who uses medical services, when and why they use these services, and how satisfied they are with the services. Because health care utilization behaviors, like lifestyle behaviors, are quite complex, various factors need to be examined to understand them. A framework for understanding these factors that has been widely used is the model devised by R. Andersen and L. A. Aday. According to their model, among the factors influencing health care utilization are: characteristics of individuals and populations at risk, the availability and quality of availability services, economic factors such health insurance, and additional access factors such as the location of health services and the availability of transportation. In addition, the level of "health need" is very important in terms of motivation and/or choice about using medical care. This approach provides an important and robust model for studying health care utilization behavior.

Dietary Behavior. Dietary behavior refers to eating patterns that people engage in, as well as behaviors related to consuming foods, such as shopping, eating out, or portion size. Dietary behavior differs from some other types of health behavior in that it is, in its basic forms, essential for life. Of course, some dietary behaviors, such as drinking alcoholic beverages or smoking cigarettes, are not necessary to sustain life. It is recognized that dietary behaviors influence the development of many chronic diseases, including coronary heart disease, some cancers (e.g. breast, colon, prostate, stomach, and cancers of the head and neck), type II diabetes mellitus, and osteoporosis. Recommendations for healthful dietary behavior include limiting consumption of high-fat foods, having a high intake of fruit and vegetables, increasing fiber, and controlling caloric intake to prevent obesity. Although most Americans know about the health consequences of unhealthful diets, many of the public health goals for dietary behavior have not been met. The prevalence of obesity and type II diabetes mellitus increased markedly in the United States and Canada during the last decade of the twentieth century.

Dietary behaviors play a role in preventing or managing disease when they are sustained over the long term. Behavioral considerations are key to any attempts to promote healthful dietary behavior. Several core issues about dietary behavior have been recognized. First, most diet-related risk factors are asymptomatic and do not present immediate or dramatic symptoms. Second, health-enhancing dietary changes require qualitative charge, not just changes in the amount of food consumed. Third, both the act of making changes and self-monitoring dietary behaviors require knowledge about foods. Thus, information acquisition and processing may be more complex for dietary change than for changes in some other health behaviors, such as smoking and exercise.

Substance-Use Behavior. Substance-use behavior focuses on the use of both licit and illicit mood-altering substances. This category of substances, typically referred to collectively as "drugs," includes tobacco, alcohol, caffeine, marijuana, cocaine, heroin, "designer drugs," and prescription medications taken improperly. These substances are ingested for various reasons, but they are similar in that they are all taken without the advice of a physician. Substance abuse, which occurs when substance use behavior is at an extreme and unsafe level, is sometimes associated with addiction, which makes it difficult to stop using the substance. Substance use and abuse are responsible for many social and health problems, and for an enormous burden of avoidable injuries in the United States each year.

Sexual Behavior. Sexual behavior may or may not involve sexual intercourse. Sexual behaviors have health implications that range from reproduction and childbearing to sexually transmitted diseases and, the most serious of these, HIV/AIDS. Taking precautions or avoiding sexual contact with multiple partners can help prevent sexually transmitted diseases (STDs) and prevent unwanted pregnancies. Sexual freedom due to social changes, a broadening of women's participation in society, and the availability of effective birth control has increased the prevalence of sexual behavior in the United States, bringing with it significant health and social problems. Attention toward this area of health behavior has increased greatly over the last two decades of the twentieth century, especially due to the AIDS epidemic.

Reckless Behavior. Reckless behavior involves individuals putting themselves in situations not normally required in daily living that substantially increase their chances of illness, injury, or death. It is often used synonymously with the terms "risk taking behavior" and "risky behavior." Reckless or risky behavior is observed in adolescents and young adults, especially young males, more often than in other demographic groups. Examples of behaviors considered risky or reckless include drinking and driving, drag racing, substance use, carrying a concealed weapon, engaging in unprotected sex, and playing extreme sports. Reckless behaviors have been shown to be strongly related to an individuals' tendency toward impulsivity and sensation-seeking.

UNDERSTANDING AND IMPROVING HEALTH BEHAVIOR

The best way to design programs to achieve positive changes in health behavior is to have an understanding of why people behave as they do and what might motivate them to change. Theories and models of health behavior have been developed for this purpose. A theory is a set of interrelated concepts, definitions, and propositions that present a systematic view of events or situations by specifying relations among variables in order to explain and predict the events or situations. Theories can be useful during the various stages of planning, implementing, and evaluating interventions. They can, for example, be used to guide an exploration of why people are or are not consuming a healthful diet or adhering to a therapeutic dietary regimen. Theories can guide the search to understand why people do or do not follow medical advice; to help identify what information is needed to design an effective intervention strategy; and to provide insight into how to design an educational program so it is successful. Thus, theories help to explain behavior, as well as suggest how to develop more effective ways to influence and change behavior. A theory about why a person chooses the foods he or she eats is one step toward successful nutrition management, but some type of change model will also be needed to guide the person toward a healthful diet.

The most widely accepted theories about health behavior have been tested in research and found to be helpful in understanding or predicting health behaviors. Health behavior is, however, far too complex to be explained by a single, unified theory, and some professionals have devised models that draw on a number of theories to help understand a specific problem in a particular setting or context.

THEORETICAL MODELS OF HEALTH BEHAVIOR

No single theory or model dominates research or practice in health-related behavior. Four of the most frequently mentioned theories of health behavior in the late 1990s were the health belief model; social cognitive theory; the stages of change/transtheoretical model; and community organization. These theories focus on a range of factors influencing behavior determinants, including factors within an individual (such as thoughts, feelings, and beliefs), factors in groups or relationships, and factors that exist in organizations, communities, and governments (such as structures, regulations, policies, and laws).

The health belief model was originally developed to explain why people did or did not take advantage of preventive services such as disease screening and immunizations. Its central thesis is that health behavior is determined by two interrelated factors: a person's perception both of the threat of a health problem and of his or her accompanying appraisal of a recommended behavior for preventing or managing the problem. The model works well, especially for early detection or for some conditions, such as infectious diseases, that people might find frightening, especially if they are uncertain about the effects of treatment methods.

The stages of change model concerns an individual's readiness to change, or to try to change, unhealthful behaviors. Its basic premise is that behavior change is a process and not an event, and that individuals are at varying levels of motivation, or readiness, to change. This means that people at different points in the process of change can benefit from different programs for change, and the programs work best if matched to their stage of readiness.

Social cognitive theory (SCT) is very complex. From this theory's perspective, people and their environments are thought to interact continuously. A basic premise of social cognitive theory is that people learn not only through their experiences, but also by watching the way other people act and the results they achieve. SCT also takes the view that, while people are influenced by the world around them, they can also actively change that world. SCT provides a foundation for several strategies for behavior change, for example the use of role models who carry out a behavior and achieve good results. Another way SCT applies to behavior change is by emphasizing that individuals change their situations by changing their own behavior.

Community organization articulates the process by which community groups identify problems or goals, mobilize resources, and develop ways to reach their goals. It includes several ways of bringing about change, including developing resources and skills; getting specialized help from outside experts; and social action, which involves people joining together for a cause, especially one that involves a particular group that is being greatly affected by a particular problem. Examples of this are AIDS activists, women's health activists working for more research on breast cancer prevention and treatment, and youths developing coalitions to fight the tobacco companies' efforts to attract customers among teenagers.

IMPORTANT CROSS-CUTTING ISSUES AND CONSTRUCTS

The various theories of health-related behavior often overlap. Not surprisingly, these explanations for behavior and models for change share several constructs and common issues.

Behavior Change as a Process. One central idea that has gained wide acceptance is the simple notion that behavior change is a process, not an event, which is the major tenet of the stages of change model. It is important to think of the change process as one that occurs in stages. It is not a question of someone deciding one day to stop smoking and the next day becoming a nonsmoker for life. Likewise, most people won't be able to dramatically change their eating patterns all at once. The idea that behavior change occurs in a number of steps is not particularly new. In fact, various multistage theories of behavior change date back to the 1940s. This theory gained wider recognition toward the end of the twentieth century, however. One example is the diffusion of innovations theory, which distinguishes the diffusion or spread of new behaviors from their adaptation or use by increasing numbers of people.

Changing Behaviors versus Maintaining Behavior Change. Even where there is good initial compliance to a health-related behavior change, a relapse to previous behavior patterns is very common. Undertaking a behavior change and maintaining the change, therefore, require different types of programs and self-management strategies. For example, someone could quit smoking by going "cold turkey," but he or she will probably be tempted again, perhaps at a party where friends are smoking. Maintaining cessation involves developing self-management and coping strategies, as well as establishing new behavior patterns that emphasize perceived control, environmental management, and improved confidence in one's ability to avoid temptation. A model called the relapse prevention model focuses very specifically on this issue.

Barriers to Actions and Decisional Balance. The concept of barriers to action, or perceived obstacles, is often mentioned in theories of health behavior. An extension of this concept involves what is known as "decisional balance." This idea is called the "net benefits of action" in the health belief model and "pros minus cons" in the stages of change model. These terms all reflect the idea that individuals engage in a relative weighing of the pros and cons of a prospective behavior change. This notion is basic to models of rational decision making, in which people intellectually think about the advantages and disadvantages of engaging in a particular action.

IMPLICATIONS FOR PUBLIC HEALTH

Understanding and improving health-related behavior is critical to the future of public health and to the well-being of individuals, and has become central to public health activities. While policies, laws, and regulations can affect health behaviors, there are also many individual factors that must be considered in these public health efforts.

Change is incremental. Many people have practiced a lifetime of less than optimal health behaviors of one sort or another. It is unreasonable to expect that significant and lasting changes will occur during a short period of time. Public health programs need to identify and maximize the benefits of positive change, pull participants along the continuum of change, and consider changes in educational programs and environmental supports to help people maintain changes over the long term.

Karen Glanz

Jay Maddock

(see also: Alcohol Use and Abuse; Behavioral Change; Behavioral Determinants; Behavioral Strategies for Reducing Traffic Crashes; Community Organization; Family Planning Behavior; Health Belief Model; Illness and Sick-Role Behavior; Preventive Health Behavior; Smoking Behavior; Social Cognitive Theory; Transtheoretical Model of Stages of Change )

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HEALTH BELIEF MODEL

The health belief model, developed by researchers at the U.S. Public Health Service in the 1950s, was inspired by a study of why people sought X-ray examinations for tuberculosis. It attempted to explain and predict a given health-related behavior from certain patterns of belief about the recommended health behavior and the health problems that the behavior was intended to prevent or control. The model postulates that the following four conditions both explain and predict a health-related behavior:

1. A person believes that his or her health is in jeopardy. For the behavior of seeking a screening test or examination for an asymptomatic disease such as tuberculosis, hypertension, or early cancer, the person must believe that he or she can have the disease yet not feel symptoms. This constellation of beliefs was later referred to generally as "belief in susceptibility."
2. The person perceives the "potential seriousness" of the condition in terms of pain or discomfort, time lost from work, economic difficulties, or other outcomes.
3. On assessing the circumstances, the person believes that benefits stemming from the recommended behavior outweigh the costs and inconvenience and that they are indeed possible and within his or her grasp. Note that this set of beliefs is not equivalent to actual rewards and barriers (reinforcing factors). In the health belief model, these are "perceived" or "anticipated" benefits and costs (predisposing factors).
4. The person receives a "cue to action" or a precipitating force that makes the person feel the need to take action.

The model soon changed shape when applied to another set of problems concerning immunization and more broadly to (the variety of) people's different responses to public health measures and their uses of health services. In these wider applications, the model substituted a belief in susceptibility to a disease or health problem for the more specific belief that one could have a disease and not know it, which had been featured in Godfrey Hochbaum's original study as the most important belief accounting for seeking screening examinations.

In the mid-1970s, a monograph devoted to the wide-ranging applications of the model described its history and experience (Becker, 1974). This was soon followed by a review of the standardized scales for measuring its several dimensions (Maiman et al., 1977). The model continued to evolve into the 1980s, largely at the hands of Marshall Becker at Johns Hopkins University and later at the University of Michigan School.

The Health Belief Model relates largely to the cognitive factors predisposing a person to a health behavior, concluding with a belief in one's self-efficacy for the behavior. The model leaves much still to be explained by factors enabling and reinforcing one's behavior, and these factors become increasingly important when the model is used to explain and predict more complex lifestyle behaviors that needs to be maintained over a lifetime.

A systematic, quantitative review of studies that had applied the Health Belief Model among adults into the late 1980s found it lacking in consistent predictive power for many behaviors, probably because its scope is limited to predisposing factors (Harrison, Mullen, and Green, 1992). One study that specifically compared its predictive power with other models found that it accounted for a smaller proportion of the variance in diet, exercise, and smoking behaviors than did the theory of reasoned action, theory of planned behavior, and the PRECEDE-PROCEED model (Mullen, Hersey, and Iverson, 1987).

Nevertheless, the health belief model continued to be the most frequently applied model in published descriptions of programs and studies in health education and health behavior in the early 1990s. It has since been displaced in frequency of application by the transtheoretical model of stages of change. It remains, however, a valuable guide to practitioners in planning the communication component of health education programs.

Lawrence W. Green

(see also: Behavioral Change; Behavioral Determinants; Health Goals; Health Outcomes; PRECEDE-PROCEED Model; Psychology, Health; Theory of Planned Behavior; Theory of Reasoned Action; Transtheoretical Model of Stages of Change )

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Harrison, J. A.; Mullen, P. D.; and Green, L. W. (1992). "A Meta-Analysis of Studies of the Health Belief Model." Health Education Research 7:107–116.

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Mullen, P. D.; Hersey, J.; and Iverson, D. C. (1987). "Health Behavior Models Compared." Social Science and Medicine 24:973–981.

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