Social Ecological Model
The Social Ecological Model (SEM) is a theoretical framework for understanding the factors that influence health and wellness at varying levels surrounding individuals, groups, and populations.
Although numerous variations of the SEM are in use throughout many areas of research including public health, the most commonly used framework is an adaptation of the research by Urie Bronfenbrenner. Bronfenbrenner’s Ecocological Systems Theory describes the broadening layers of influence over individuals’ behavior from “micro” to “macro.”
The Health Equity Toolkit includes a basic version of the SEM developed from a combination of Bronfenbrenner’s model and additional psychological and public health research. This model is applicable to health promotion practice and describes factors that influence health at the individual, interpersonal, organizational, community, and systems levels.
Interventions to combat obesity disparities may take place at all levels of the SEM. The Health Equity Toolkit, however, emphasizes programs implemented at the outermost levels of the SEM.
Scroll over the different levels of the SEM model below for examples of obesity programs!
The primary circle of the SEM represents the individual ultimately affected by all other levels of the SEM. Individual level factors influencing health include behaviors, knowledge, attributions, and beliefs.
The next tier in the SEM represents individuals’ interactions with one another, or relationships shared within social networks such as families, peer groups, and friendship-based social networks
Institutions and Organizations
This tier represents policies and rules specific to assemblies of individuals and their relationships. Common examples of assemblies include schools, religious or faith-based institutions, and the workplace.
Communities can be described as a larger societal construct comprised, in varying combinations, of the three smaller tiers of the SEM. Communities are composed of individuals as they participate in interpersonal relationships within various groups of institutions and organizations. Communities may be defined geographically, politically, culturally, or by other common characteristics.
Structures and Systems
This outermost tier of the SEM represents the local, state, and federal structures and systems which affect the built environment surrounding communities and individuals.
Additional SEM Resources
For additional reading, check out these publications:
- Bronfenbrenner, U. (1977). Toward an experimental ecology of human development.” American Psychologist, 32: 513-531.
- Bronfenbrenner, U. (1979). The Ecology of Human Development. Cambridge, Massachusetts, Harvard University Press.
- McLeroy, K., Bibeau, D., Steckler, A., & Glanz, K. (1988). An ecologic perspective on health promotion programs. Health Education Quarterly, 15: 351-377.