Getting complex about reality, or getting real about complexity?

How can we solve the persistent problem of increasing inequality that is facing public health?

The Health Foundation has been working with Dr Harry Rutter to develop a new model of evidence that will inform public health research, policy and practice. I was invited to attend a workshop to discuss the ways in which the systems we use to generate evidence can be improved for public health.

Much of the conversation explored the reality of trying to generate research evidence for an incredibly complex set of interventions and policies, which interact in multiple ways for different populations, at different levels.

Trying to improve childhood obesity, for example, requires intervening in homes, schools, communities and the workplace. It requires infrastructure and built environment improvements, taxation, and regulation of planning laws, as well as health promotion and literacy.

Coordinating these is an immensely difficult task, yet it’s a task we must tackle if we want to see improvement. We know that research funds and resources are increasingly targeted towards biomedical institutions and programmes, but there’s limited evidence that interventions which operate at the individual or group level actually help address complex social problems.

In fact, it looks increasingly as though current approaches often inadvertently cause harm. Public health policymakers are in the unenviable position of needing to act, but having a limited range of tools available to them. They know that policy instruments are likely to be interacting with one another but are unable to evaluate how, or for whom.

Complex systems are non-linear, emergent and adaptive. In other words, they’re extremely difficult to research using standard social research methods. Using the example of childhood obesity above, we may wish to use qualitative, quantitative, experimental, longitudinal, modelling and simulation methods; participatory and deliberative methods. One researcher is unlikely to have the expertise to manage all these tasks. It is also challenging for one policymaker, or even a team of policymakers, to have oversight of all research likely to be relevant for one policy outcome. Yet, it is important that policies are based on the best available evidence.

How can this gap be bridged? One approach is to move away from the linear model of evidence informing policy and towards an idea of an evidence ecosystem. In this approach, the process of evidence provision becomes more conversational.

Learning how to identify and engage with stakeholders across government and research organisations is just the first start in mapping the complex system within which we are hoping to create change. Talking regularly with policymakers about upcoming challenges is likely to help researchers produce more policy-relevant evidence. Equally, understanding the upcoming policy agenda will help useful evidence syntheses to be produced, which can help inform discussions about how different policy instruments may interact.

But co-producing evidence for policy, and co-producing policy options themselves, is intensely difficult and expensive. Tools and approaches to help us navigate this new territory are in their infancy, and the public health research community is only just starting to embrace the radically different way of doing research which coproduction entails.

We need to learn how to take the problem of complexity seriously, in both developing new research methods and in learning how to communicate complex research to a policy audience. This could be achieved through embedding complexity training in public health education and doctorates, and by investing in coordinated research programmes and schools.

A revitalised, refocused public health research and practitioner community producing excellent, relevant research can only do so much. For complexity to be taken seriously, we also need greater coordination between government departments, and with local government. We need political leaders who are unafraid to experiment and change course, to discuss uncertainty and failure. Ultimately, we need politicians, partners, and the public on board.

Dr Kathryn Oliver is an Associate Professor of Sociology and Public Health and leads the Evidence Synthesis theme for the Centre for Evaluation at the London School of Hygiene and Tropical Medicine. She contributed to a roundtable at the Health Foundation on using complex systems thinking to inform practice.