For a long time, epidemiologic studies have used epidemiologic designs such as cohorts, case controls, experimental designs as well as cross-sectional. The psychological epidemiology emphasizes on investigating the impact of stress in health outcomes. The earlier researchers studied the topic by using cross-sectional investigations of the available populations while the present day researchers incorporate a diverse study population in the epidemiologic studies. An example of a methodology that is relevant in the psychological and social epidemiologic studies is the Community-based participatory research (CBPR). In CBPR, the research team collaborate and work together with the community organizations to investigate the health-related issues that affect a specific community. The research team thus have access to the community, and they can collect the research data that will be necessary for improving the quality of healthcare of the community. Moreover, the results from the CBPR facilitate the training and empowering community organization to carry out independent research activities that will specifically address the needs of the community.

There has been an increased interest to study the role played by the social environment in health. The social environment entails the behavioral, personality, as well as the cultural characteristics of a specific population. The social environment provides a background for understanding the psychosocial factors, and the result is that it has an impact on the health of individuals from both developed and developing nations around the world.  For example, the life expectancy of individuals in developing countries is lower than that of individuals in developed countries.

The primary reason for this difference in life expectancy is poverty. It circulates to various aspects such as malnutrition due to insufficient food for the household, infectious diseases that result from poor living standards and lack of proper hygiene. The individuals also lack preventive health care services to minimize the spread of infectious diseases. The social environment, therefore, contributes to morbidity and mortality rates. It has an impact on the health of individuals from the developed world through other conditions such as unhealthy lifestyle like the use of illegal drugs, diet, smoking, and lack of exercise. These factors contribute to diseases and can result in the death of individuals.