Recent advances in psychological, medical, and physiological research have led to a new way of thinking about health and illness. This conceptualization, which has been labeled the biopsychosocial model, views health and illness as the product of a combination of factors including biological characteristics (e.g., genetic predisposition), behavioral factors (e.g., lifestyle, stress, health beliefs), and social conditions (e.g., cultural influences, family relationships, social support).
Psychologists who strive to understand how biological, behavioral, and social factors influence health and illness are called health psychologists. Health psychologists use their knowledge of psychology and health to promote general well-being and understand physical illness. They are specially trained to help people deal with the psychological and emotional aspects of health and illness. Health psychologists work with many different health care professionals (e.g., physicians, dentists, nurses, physician's assistants, dietitians, social workers, pharmacists, physical and occupational therapists, and chaplains) to conduct research and provide clinical assessments and treatment services. Many health psychologists focus on prevention research and interventions designed to promote healthier lifestyles and try to find ways to encourage people to improve their health. For example, they may help people to lose weight or stop smoking. Health psychologists also use their skills to try to improve the healthcare system. For example, they may advise doctors about better ways to communicate with their patients.
Health psychologists work in many different settings including the UK's National Health Service (NHS), private practice, universities, communities, schools and organizations. While many health psychologists provide clinical services as part of their duties, others function in non-clinical roles, primarily involving teaching and research. Leading journals include Health Psychology, the Journal of Health Psychology, the British Journal of Health Psychology, and Applied Psychology: Health and Well-Being. Health psychologists can work with people on a one-to-one basis, in groups, as a family, or at a larger population level.
- Clinical health psychology (ClHP)
- ClHP is the application of scientific knowledge, derived from the field of health psychology, to clinical questions that may arise across the spectrum of health care. ClHP is one of many specialty practice areas for clinical psychologists. It is also a major contributor to the prevention-focused field of behavioral health and the treatment-oriented field of behavioral medicine. Clinical practice includes education, the techniques of behavior change, and psychotherapy. In some countries, a clinical health psychologist, with additional training, can become a medical psychologist and, thereby, obtain prescription privileges.
- Public health psychology (PHP)
- PHP is population oriented. A major aim of PHP is to investigate potential causal links between psychosocial factors and health at the population level. Public health psychologists present research results to educators, policy makers, and health care providers in order to promote better public health. PHP is allied to other public health disciplines including epidemiology, nutrition, genetics and biostatistics. Some PHP interventions are targeted toward at-risk population groups (e.g., undereducated, single pregnant women who smoke) and not the population as a whole (e.g., all pregnant women).
- Community health psychology (CoHP)
- CoHP investigates community factors that contribute to the health and well-being of individuals who live in communities. CoHP also develops community-level interventions that are designed to combat disease and promote physical and mental health. The community often serves as the level of analysis, and is frequently sought as a partner in health-related interventions.
- Critical health psychology (CrHP)
- CrHP is concerned with the distribution of power and the impact of power differentials on health experience and behavior, health care systems, and health policy. CrHP prioritizes social justice and the universal right to health for people of all races, genders, ages, and socioeconomic positions. A major concern is health inequalities. The critical health psychologist is an agent of change, not simply an analyst or cataloger. A leading organization in this area is the International Society of Critical Health Psychology.
Health psychology, like other areas of applied psychology, is both a theoretical and applied field. Health psychologists employ diverse research methods. These methods include controlled randomized experiments, quasi-experiments, longitudinal studies, time-series designs, cross-sectional studies, case-control studies, qualitative research as well as action research. Health psychologists study a broad range of health phenomena including cardiovascular disease, (cardiac psychology), smoking habits, the relation of religious beliefs to health, alcohol use, social support, living conditions, emotional state, social class, and more. Some health psychologists treat individuals with sleep problems, headaches, alcohol problems, etc. Other health psychologists work to empower community members by helping community members gain control over their health and improve quality of life of entire communities.