How do we make the financial case for investing in public health? It’s an important question for Public Health England, because unless our recommendations and advice stack up economically, they are less likely to be implemented, however compelling the scientific evidence. At a time of acute pressure on budgets, it’s even more incumbent on us to demonstrate value for money.
It’s true that sometimes public health interventions can actually save costs. Vaccination and immunisation programmes are examples from within the health system. But there’s growing evidence of examples that go beyond the health system. This cites data ranging from cycle trails, to salt reduction in food, and programmes to promote mental health in the workplace. There’s yet on the cost savings to be had from speed limits and safety cameras to reduce traffic injuries, interventions to reduce bullying in schools and affordable warm housing.
Where public health interventions can reduce expenditure (in health or other sectors), they should be highlighted and implemented systematically. But we don’t think this should be the main goal of prevention and health promotion. After all, we don’t typically measure the success or the desirability of clinical treatment based on whether it saves the NHS money. It would be inconsistent to hold public health to a different standard since resource allocation decisions are being made from the same total health budget.
We think the appropriate test for public health interventions is the extent to which they can improve population health and wellbeing in ways that are cost-effective and make the most efficient use of our scarce resources compared with the alternatives. The impact on health inequalities is also important, as sometimes improving overall health and wellbeing can actually worsen inequalities. Increasingly, therefore, assessments of cost-effectiveness will need to account for the impact on health inequalities.
In England, we’re fortunate to have an expanding evidence base for public health interventions through the work of the National Institute for Health and Care Excellence (NICE). NICE generally considers that a treatment is if it costs £20,000 or less to provide a year of the best quality of life available, compared to alternatives. The overwhelming majority of the public health interventions that NICE has assessed by this measure, and many would make the grade if the threshold were much lower, say around £5,000.
A few key factors influence the cost-effectiveness calculation, and they’re not without their challenges.
The first is the time-frame that’s used to measure the impact of public health. This can vary dramatically: it’s taken for the UK’s salt reduction programme to affect the average salt intake of the population. But if we’re going to tackle extremely complex challenges like obesity or the design of our cities, we could be looking at decades or even generations. Some investments won’t pay off quickly and we have to have the confidence to spell that out - and to challenge existing approaches to assessing the cost-effectiveness of public health interventions.
The second key factor is the perspective that’s used when we assess an intervention. Do we measure just the health benefits or the wider benefits to society? Excess alcohol, for example, imposes , ranging from lost productivity to domestic violence. The economic case for public health interventions can be stronger if we take the wider societal view, but historically, the incentives haven’t been in place to take a cross-system approach. That’s why the return of public health to local government is such a huge opportunity, because local government is ideally placed to recognise the economic links between public health and other sectors such as policing, transport and housing.
The third factor that influences cost-effectiveness is how well we are able to align the size of an intervention – in terms of how many people it reaches – with the prevalence of the problem we’re worried about. So a problem that is very widespread would justify a population approach. Other types of problems may require a more targeted approach: what’s been elsewhere. This approach encourages us to be efficient in who we target as well as in how we deliver treatment. This may be particularly important when dealing with rare but expensive diseases where it is necessary to target preventative activity very carefully. Even more common infectious diseases (for example, tuberculosis), for which there are proven cost-effective interventions, require this careful targeting approach so that we can maintain our momentum in tackling them.
We believe PHE has an important role to play, not just in highlighting and disseminating the evidence on cost-effectiveness, but also in helping to make it useful and relevant to our partners across the system and to local government in particular. That’s why PHE is supporting the implementation of NICE’s tools on Return on Investment in core public health areas, such as tobacco control, alcohol and physical activity. You can find out more information on the tobacco control tool , as well as information on the weight management economic tool published by PHE’s obesity team
Of course these tools are not solutions in themselves: decisions about what to prioritise will be based on a host of factors other than economic considerations. PHE has a key role to play in assisting our partners to think about these issues and to clarify the underlying principles upon which prioritisation decisions are made. The onus is on PHE and its partners to make the best use of the available economic evidence, tools and resources to help with making difficult choices.