On the Distinction—or Lack of Distinction—Between Population Health and Public Health

The term “population health” is increasingly used by academics, practitioners, policymakers, funders, professional organizations, and even consulting companies.^1–3 Yet debates on what the term means are common,^1,2 and its use has understandably created soul-searching and head-scratching in public health venues. Should the public health community embrace the term or distinguish itself from it? Does the use of the term signal a transformation of the way we approach health or is it merely a passing fad?

The use of the term dates back to at least as early as 1990, when Evans and Stoddart described the population health approach as a framework characterized by a broad definition of health, that recognized determinants outside the health care system, and explicitly acknowledged trade-offs between investing in health care and investing in other social goods.⁴ More than 10 years ago, Kindig and Stoddart defined population health more literally as “the health outcomes of a group of individuals, including the distribution of such outcomes within the group.”^5(p380) Subsequent definitions have proposed refinements,⁶ but a key element has been the focus on the aggregate or population dimension, as distinct from the health of an individual (the focus of clinical medicine).

The recent explosion of the use of the term in the medical world, in phrases like “population health management,” has unfortunately narrowed the concept in two important ways.¹ First, “population” refers to groups of patients, receiving care with a certain provider, covered by a certain health plan, sharing a certain health condition, or living in a certain geographic area. Second, the emphasis is on improving the outcomes of care and reducing costs. By contrast, the term population health has also been increasingly embraced by social scientists to signal a much broader approach that, like the Evans and Stoddart framework,⁴ emphasizes the primal role of factors outside the traditional biomedical model. This use of population health is reminiscent of the term saude coletiva (collective health) first used in the late 1970s in Latin America.⁷

Some make a special effort to distinguish population health from public heath. It is posited that public health has a greater focus on government and does not sufficiently recognize the role of the health care system in health² (i.e., the argument is that public heath is primarily government oriented and not biomedical enough). By contrast, others argue that population health has a broader view of the drivers of health than public health because public health remains tied to service provision and to its more powerful sister, medicine. Or in other words that public health is too biomedical and personal service oriented to really encompass the role of broader societal factors.²

Much of this is a semantic discussion. What really matters are the questions we pose regarding the health of the public, the answers we obtain, and the actions we take in response. Whether we call this approach public health or population health is, in all honesty, irrelevant. But these semantic discussions are also an opportunity to clarify assumptions and approaches. They allow us to specify the kind of science we hope to build and the types of understandings and consequent actions we hope will flow from it. The terminological discussion is an opportunity for the public health community to clarify what we believe public health really is (or should be) about.

In its most transformative sense, the recent use of the term population health has come to signify a conceptual approach to understanding the drivers of health and consequently the strategies most useful to improve health. As I see it, this conceptual approach has two key principles: (1) the need to consider factors defined at multiple levels of organization in understanding health and acting to improve it (this implies integrating social and biologic processes), and (2) an explicit concern with health equity because we cannot substantially improve the health of the population as a whole without addressing health inequities and because the drivers of health inequities are often the drivers of the health the population generally. The population health approach does not exclude health care services, but it does place them in context. It encompasses many sectors (including the government) and disciplines. It does not view the health of an individual in contrast to (or as distinct from) the health of a population but rather articulates how patterns of population health result from the dynamic and interacting relations between individuals, between individuals and their contexts, and between individuals and the services that they have access to and use. It has a direct concern with translation of science into actions, and views science and action as linked and reinforcing each other.

This definition of population health is consistent with broad definitions of public health in which the term is used to refer to both a field of study (understanding the drivers of the health of the public, encompassing distal to proximal factors)⁸ and a set of actions (“. . . what we as a society do collectively to assure the conditions for people to be healthy”^9[p2]). Semantic debates aside, fields are defined by what those who identify themselves with the field actually do. I posit that the broad view of public health is consistent with the research, training, and policy agendas not only of academic public health but also increasingly of governmental public health, which sees its responsibilities as linked to addressing the more distal determinants of health through a range of actions and partnerships.¹

THE MORE SYNONYMS WE HAVE, THE BETTER

Does the emergence of the term population health mean we should stop using the term public health? Should AJPH change its name to the American Journal of Population Health? Of course not. There is a long a distinguished tradition behind the term public health that is entirely aligned with the principles of the broad population health approach.¹ And the connections of the term public health to governmental responsibility to protect the health of the public and to real and practical actions in the field¹⁰ are valuable and should not be discarded. At the same time, if using the term population heath in the context of public health research, education, and action and indeed using it interchangeably with the term public health helps reinforce a broad view of public health that is consistent with what most public health academics and practitioners espouse today, then I say lets use it. Are all versions of public health compatible with the principles of the broad population health approach? Certainly not. But neither are all versions of population health, as amply demonstrated by how this terms is being used in the medical field.¹

The Oxford English Dictionary defines public as “of or concerning the people as a whole.” I posit that this is the primary meaning of public in the term public health. Improving and protecting the health of the population is a key social goal that requires a broad interdisciplinary science and many different kinds of actions. The more synonyms we have to refer to approaches that will allow us to do this, and the more disciplines and sectors that identify with this approach, the better.