What is Health improvement in public health

‘Population health’ holds that there are a wide range of determinants of health and wellbeing, many of which lie beyond the reach of health and care services, that determine the health of a population. An emphasis on reducing inequalities in health as well as improving health overall is core to population health approaches.

There are several definitions of population health in use. The King’s Fund defines it as:

Population health is sometimes confused with, or seen as synonymous with, public health. Public health bodies and local directors of public health do have a responsibility to understand the needs of their population and the organisation and delivery of some public health services, such as weight management, smoking cessation or sexual health services, as well as protecting people’s health from external threats, eg, disease outbreaks.

While this is an invaluable skillset, there is often a mis-perception that health and wellbeing of a population is only the responsibility of public health professionals; those specialists who are explicitly trained to plan and deliver public health services. The reality is that population health requires input from numerous partner organisations, such as the NHS, community groups, local authorities and political leaders, as well as public health teams whose action and influence should be seen as key in a population health approach.

Confusingly, the phrase ‘population health management’ is also widely used, with a specific meaning that is narrower in focus than population health. Population health management is a data-driven tool or methodology that refers to ways of bringing together health-related data to identify a specific population that health and care systems may then prioritise for particular services. For example, data may be used to identify groups of people who are frequent users of accident and emergency departments, to offer preventive interventions that improve health and reduce demand on acute services. One common approach to population health management is ‘population segmentation’.

Our health is shaped by a range of factors, as set out in Figure 1.

Figure 1 - What affects our health?

Source: Dahlgren G, Whitehead M 1993

Recognising this, The King’s Fund vision for population health sets out a framework for population health, that focuses activity across four pillars.

• The wider determinants of health: these are the most important driver of health. In addition to income and wealth, these determinants include education, housing, transport and leisure.
• Health behaviours and lifestyle: are the second most important driver of health. They include smoking, alcohol consumption, diet and exercise. For example, while reductions in smoking have been a key factor in rising life expectancy since the 1950s, obesity rates have increased and now pose a significant threat to health outcomes.
• Places and communities: our local environment is an important influence on our health behaviours, and there is strong evidence of the impact of social relationships and community networks, including on mental health.
• Integrated health and care systems: this reflects the growing number of patients with multiple long-term conditions and the need to integrate health and care services around their needs rather than within organisational silos.

Improving population health requires action on all four of the pillars and, crucially, the interfaces and overlaps between them. 

For example, a population health approach to planning a new housing development would include building in active travel and green space, considering the size and design of individual homes, ensuring homes are affordable to all sections of the community, and action to allow people to stay independent as they age in their homes. The Healthy New Towns initiative was one example of how an emphasis on all these and more came together in sites around the country. 

The King’s Fund describes this way of applying a population health framework in a place, whether nationally, regionally or locally, as the way to develop an effective ‘population health system’. This is illustrated in Figure 2.

Figure 2 - A population health system

Source: Buck et al 2018

Given the breadth and complexity of things that affect our health, responsibility and accountability for driving population health improvement can be unclear as the levers for change sit across multiple organisations. Importantly, action to improve population health effectively needs to be taken at three levels:

• national, eg, government, arm’s length bodies
• regional, eg, integrated care systems
• local, eg, individual cities, towns and neighbourhoods.

In recent years population health has increasingly come to the fore as policy has evolved to more explicitly recognise the complex drivers of health and wellbeing and their interconnections.

In 2018, the NHS Long Term Plan set out the expectation that in time integrated care systems (ICSs) would bring together NHS, local authority, and voluntary sector and other community groups to help deliver population health approaches. Now, the Health and Care Act 2022 has established ICSs as statutory bodies with a responsibility to improve population health, and it also introduces new duties for the NHS to tackle health inequalities.

At the same time, reforms to the national public health system led to the creation of the Office for Health Improvement and Disparities (OHID), which sits within the Department for Health and Social Care. OHID leads population health improvement policy development and advises the cross-government Health Promotion Taskforce, which is responsible for leading cross-government efforts to improve population health, including the wider determinants of health and community development.

While national policy clearly affects population health directly and indirectly, much of the shaping, prioritisation and delivery of population health ambitions lies below national level in regional and local systems and places. Effective local system leadership is therefore vital. The complexity of local structures means that approaches will vary from place to place with ICSs, local authorities, community groups and political leaders such as elected mayors all having key roles to play.

Delivering an effective population health approach will take concerted, systemic and coherent efforts over the course of many years. New structures within the health and care system provide a strong foundation to deliver this, though change will be driven by local and regional teams.