Originally posted 5/18/2010
What is population health?
The population health perspective taken by this blog is a broad one, as the model below illustrates (1) [This model was adapted from the original Evans and Stoddart field model (2) and expands on Kindig and Stoddart (3)].
Population health is defined as the health outcomes of a group of individuals, including the distribution of such outcomes within the group. (3,4) These groups are often geographic populations such as nations or communities, but can also be other groups such as employees, ethnic groups, disabled persons, prisoners, or any other defined group. The health outcomes of such groups are of relevance to policy makers in both the public and private sectors.
Note that population health is not just the overall health of a population but also includes the distribution of health. Overall health could be quite high if the majority of the population is relatively healthy—even though a minority of the population is much less healthy. Ideally such differences would be eliminated or at least substantially reduced.
The right hand side of the figure indicates that there are many health determinants or factors, such as medical care systems, individual behavior, genetics, the social environment, and the physical environment. Each of these determinants has a biological impact on individual and population health outcomes.
Isn’t this so broad to include everything?
Population health, as defined above, has been critiqued as being so broad as to include everything—and therefore not very useful in guiding specific research or policy. The truth is, no one in the public or private sectors currently has responsibility for overall health improvement. Policy managers, for example, tend to have responsibility for a single sector while advocacy groups likewise focus on a single disease or factor.
The inherent value of a population health perspective is that it facilitates integration of knowledge across the many factors that influence health and health outcomes. For population health research, specific investigations into a single factor, outcome measure, or policy intervention are relevant, and may even be critical in some cases–but they should be recognized as only a part and not the whole.
What is the difference between population health and public health?
The distinction between public health and population health deserves attention since it has been at times both confusing and even divisive. Traditionally, public health has been understood by many to be the critical functions of state and local public health departments such as preventing epidemics, containing environmental hazards, and encouraging healthy behaviors.
The broader current definition of the public health system offered by the Institute of Medicine reaches beyond this narrow governmental view. Its report, The Future of the Public’s Health in the 21st Century, calls for significant movement in “building a new generation of intersectoral partnerships that draw on the perspectives and resources of diverse communities and actively engage them in health action (5).”
However, much of U.S. governmental public health activity does not have such a broad mandate even in its “assurance” functions, since major population health determinants like health care, education, and income remain outside public health authority and responsibility. Similarly, current resources provide inadequate support for traditional–let alone emerging–public health functions. Yet for those who define public health as the “health of the public,” there is little difference from the population health framework of this blog.
1. Kindig D, Asada Y, Booske B. (2008). A Population Health Framework for Setting National and State Health Goals. JAMA, 299, 2081-2083.
2. Evans R, Stoddart GC. (1990). Producing Health, Consuming Health Care. Soc. Sci. Med. 33, 1347-1363.
3. Kindig, DA, Stoddart G. (2003). What is population health? American Journal of Public Health, 93, 366-369.4. Kindig DA. (2007). Understanding Population Health Terminology. Milbank Quarterly, 85(1), 139-161.
5. Institute of Medicine. (2002). The Future of the Public’s Health in the 21st Century. Washington, DC, The National Academies Press.