Population health and equity

Population health is an approach used within public health systems — a framework for thinking about why some populations are healthier than others, as well as the policy development, research and resource allocation that flow from it (Young 1998). A narrow view of population health is that ‘population health rests largely on shaping the distribution of risk in a population so that fewer people are exposed to risky situations’ (Berkman & Melchior 2006: 55).

A broader view of population health is that it describes both a level of analysis about risk exposure, the health outcomes of whole populations, or sub-populations, and the distribution of outcomes across those various populations (e.g. youth, children, refugees, older people) (Kindig 2007). Population health is increasingly concerned with studies and programs addressing health determinants (Berkman & Melchior 2006; Kindig 2007).

So, population health can be narrowly defined in terms of risks and associated health outcomes, but there is support for broader conceptualisation of population health as encompassing the multiple determinants of such health outcomes, however these outcomes are measured. These determinants include: access to health care and public health interventions; socioeconomic environments including income, education, employment, social support, gender and culture; physical environments including urban design, clean air and water; genetics or biology; and individual and group behaviours including social norms for particular groups (Kindig 2007).

Health Canada (2002) argues for an even broader conceptualisation of population health, saying it should expect outcomes that go far beyond just health improvement:

Geoffrey Rose, now regarded as a classic thinker and researcher about public and population health, posed a key question for public health: ‘Why are some people healthy and others not?’ (Rose 1981, 1992, 2001). To answer that question, he said (Rose 1992: 62):

Both high-risk and population strategies have been developed to influence the distribution of illness across the population. A high-risk strategy is one that targets the right patient at high risk of developing a more serious condition, such as pregnant women or overweight men who are smokers. The population strategy is one that attempts to control the determinants of incidence, and thus to shift the distribution of exposure across the whole population. This gives rise to the prevention paradox, which is that a large number of people at small risk may give rise to more cases than the small number who are at high risk, which is to say that ‘a preventive measure that brings large benefits to the community offers little to each participating individual’. In other words, many people must take precautions in order to prevent illness in only a few, such as immunisation.

In theory, population health work should take account of the patterns of health determinants, and policies and interventions that link outcomes with determinants. But in reality, only a narrow range of determinants are considered in population health work by governments which focus on relationships between patterns of illness and disease in relation to socioeconomic factors and, to a lesser extent, racial and ethnic group differences. Good population health requires intersectoral approaches to programs and a focus on the needs of those with disadvantaged health status, aiming to reduce health and social inequities.

Typically, both public health and population health strategies are more ‘upstream’ than medical treatment services, which are classified primarily as ‘downstream’. Upstream strategies are focused on social and environmental change, and health-promoting policies and practices. Figure 9.1 illustrates downstream–upstream causal pathways towards the development of disease and illness.

Figure 9.1 The drivers for health lie outside the health sector

Source: Keleher 2006: 51

Universal and targeted public health approaches

Other chapters (1, 2, 10, 11, 12, 13) discuss the higher incidence of poor health among socio-economically disadvantaged groups and problems of inequity. Public health places emphasis on high quality, universal programs such as immunisation, maternal and infant health, and cancer screening programs that are available to the whole population. As health inequities increase, a balance needs to be found for targeted programs that are tailored to meet specific needs of vulnerable populations and groups.