the discipline. Objectives Understanding behavioral and contextual factors Health psychologists conduct research to identify behaviors and experiences that promote health, give rise to illness, and influence the effectiveness of health care. They also recommend ways to improve health care policy. Health psychologists have worked on developing ways to reduce smoking and improve daily nutrition in order to promote health and prevent illness. They have also studied the association between illness and individual characteristics. For example, health psychology has found a relation between the personality characteristics of thrill seeking, impulsiveness, hostility/anger, emotional instability, and depression, on one hand, and high-risk driving, on the other. Health psychology is also concerned with contextual factors, including economic, cultural, community, social, and lifestyle factors that influence health. Physical addiction impedes smoking cessation. Some research suggests that seductive advertising also contributes to psychological dependency on tobacco, although other research has found no relationship between media exposure and smoking in youth. OHP research indicates that people in jobs that combine little decision latitude with a high psychological workload are at increased risk for cardiovascular disease. Other research reveals a relation between unemployment and elevations in blood pressure. Epidemiologic research documents a relation between social class and cardiovascular disease. Health psychologists also aim to change health behaviors for the dual purpose of helping people stay healthy and helping patients adhere to disease treatment regimens (also see health action process approach). Health psychologists employ cognitive behavioral therapy and applied behavior analysis (also see behavior modification) for that purpose. Preventing illness Health psychologists promote health through behavioral change, as mentioned above; however, they attempt to prevent illness in other ways as well. Health psychologists try to help people to lead a healthy life by developing and running programmes which can help people to make changes in their lives such as stopping smoking, reducing the amount of alcohol they consume, eating more healthily, and exercising regularly. Campaigns informed by health psychology have targeted tobacco use. Those least able to afford tobacco products consume them most. Tobacco provides individuals with a way of controlling aversive emotional states accompanying daily experiences of stress that characterize the lives of deprived and vulnerable individuals. Practitioners emphasize education and effective communication as a part of illness prevention because many people do not recognize, or minimize, the risk of illness present in their lives. Moreover, many individuals are often unable to apply their knowledge of health practices