Improving a Population’s Health Requires Collaboration and a Focus Upstream

population health

As the province continues to navigate the pandemic, lessons have emerged, particularly in terms of gaps in health equity and care. These insights will help build an even stronger health system, one which includes a deliberate focus on achieving greater health equity, integration of health and social services, and initiatives that contribute to the overall improvement of the health of the population. This article is the first in a series exploring the concept of population health, with the goal of considering the role of a hospital in producing population health. This series will feature successful initiatives of health systems that have invested beyond their walls to improve the health of their communities.

​​A classic public health tale credited to medical sociologist, Irving Zola, tells a story that illustrates the tension between responding to acute health care issues in a population (e.g., cancer, stroke, heart attack, etc.) and addressing their root causes. In the story, a person sees a man drowning in a river current and saves him. But, soon enough, this person is quickly forced to return to the river to rescue more drowning people. Finally, after rescuing many others, the person walks upstream to try and understand what is causing people to fall into the river in the first place[1]. This classic tale highlights the important question about understanding what impacts a community's or population's health.

In 1974, Marc Lalonde, Canada's then Minister of National Health and Welfare, changed the way the world thinks about health when he published, A New Perspective on the Health of Canadians[2](Lalonde Report). The Lalonde Report emphasized the need to look beyond the traditional health care system in order to improve the health of the public. From the time it was published, there has been increasing evidence from around the world demonstrating that spending more on health care will not lead to substantial improvements in population health. In fact, the report presented a revolutionary new approach, which to this day, is credited to Canada.

What is population health?

Population health is defined as "the health outcomes of a group of individuals, including the distribution of such outcomes within the group"[3]. While there is no single accepted definition of population health, key aspects of this concept are important to understand:

    1. Population health considers a broader notion of health that acknowledges well-being beyond the physical state.
    2. Population health considers a group of individuals or a population which can be defined according to a geographic region, such as a country or a community, but also by other factors, such as a group of employees, an ethnic group, or patients of a health system, etc.[4]
    3. Population health is about measuring health outcomes and recognizing the determinants that impact health (e.g., social circumstances, individual behaviour, physical environment, medical care, genetics and biology). Health outcome indicators may include life expectancy at birth, health-adjusted life expectancy, infant mortality, suicide mortality, perceived mental health, mental illness hospitalization rate, diabetes, disability, obesity, etc. [5]
    4. Arguably the most important aspect of population health, considers the distribution of those health outcomes across that population, which takes health inequality and inequity into consideration.

Many factors influence health including genetics, medical care, physical environment, social circumstances and individual behaviour[6]. The Social Determinants of Health (SDH) are the non-medical factors that influence health outcomes. They are the conditions in the environments where people are born, grow, work, live, and age, and the wider set of forces and systems shaping the conditions of daily life. These forces and systems include economic policies and systems, development agendas, social norms, social policies, and political systems[7]. Lalonde asserted that improvements in the SDH are crucial for a healthy population.

Social Determinants of Health: The Canadian Facts considers 17 SDH to be the primary factors that shape the health of Canadians which include: income and income distribution; education; unemployment and job security; employment and working conditions; early child development; food insecurity; housing; social exclusion; social safety net; health services; geography; disability; indigenous ancestry; gender; immigration; race; and globalization.

More recently, individuals, communities and organizations are calling for an upstream approach to health – one that addresses the SDH in order to reduce health disparities[8].  In 2012, Canada, along with other WHO Member States, endorsed the Rio Political Declaration on Social Determinants of Health, pledging to take action to promote health equity by improving SDH.

Who's responsible for producing population health?

Traditionally, public health has been responsible for population health and disease control while the health care sector has focused on addressing the immediate, clinical needs of a population and community agencies have focused on the resources and services needed for healthy living (e.g., housing, transportation, supports for activities of daily living, etc.). However, there is growing recognition that all sectors must work in partnership to truly improve the health of the population as no one single entity can tackle the upstream social conditions on its own[9].

In Ontario, recent large-scale efforts initiated by government to establish a more integrated system have provided another opportunity to improve population health by addressing upstream factors needed for individuals and communities to thrive. Prior to the COVID-19 pandemic, Ontario's health care system began a significant system transformation which included the establishment of Ontario Health Teams (OHTs). However, even before OHTs were established, hospitals – recognizing their role in producing population health – had been using population health management approaches to design care for patients. The transformation that was underway with OHTs, which in some ways has been accelerated by the pandemic, aims to connect groups of providers and organizations to deliver integrated care across the full continuum for a defined population.

The next article in the series will highlight a few Ontario initiatives focused on population health and the great work that has been accomplished or is underway. The OHA has also developed a resource page on Population Health which includes several one-page snapshots highlighting important concepts under this broader topic.


[1] National Collaborating Centre for Determinants of Health (2014). Let's talk: Moving upstream.

[2] National Collaborating Centre for Determinants of Health (2020). A new perspective on the health of Canadians. Resource library.

[3] Kindig, D. & Stoddart, G. (2003). What is population health? American Journal of Public Health, 93(3), 380-383,

[4] National Collaborating Centre for Determinants of Health (2014). Let's talk: Moving upstream.

[5] Public Health Agency of Canada (2018). Key health inequalities in Canada: A national portrait. Pan-Canadian health inequalities reporting initiative. 

[6] Choi, E. & Sonin, J. (2018, February). Determinants of health. GoInvo.

[7] World Health Organization (WHO) (n.d). Constitution.

[8] National Collaborating Centre for Determinants of Health (2014). Let's talk: Moving upstream.

[9] Green, K. & Zook, M. (2019, October 29). When talking about social determinants, precision matters. Health Affairs Blog.