Investigating the use of Health Impact Assessments to assess decisions made outside of town planning in UK local authorities

Background: Population health across the UK has stagnated over the last 14 years, whilst health inequalities have widened. Much of this deterioration in health is driven by the wider determinants - the factors outside of health and care services that impact our health, such as our houses, our jobs, and our surroundings. Many of these factors are influenced or determined by local authorities. Accordingly, policymakers in local authorities should consider health in all their decisions; Health Impact Assessments (HIAs) can be used to do this. However, little is known about whether HIAs are widely used across local authorities for decisions made outside of town planning, or whether their use is beneficial; this study aims to investigate these questions. Methods: We designed and disseminated two surveys comprising both quantitative and qualitative questions for local authority officers working both within and outside of public health to gather experiences and opinions regarding HIA use in their organisations. Results: While HIAs are used across a number of local authorities for decisions made outside of town planning, their use is less widespread than for town planning decisions. Public health staff expressed good engagement with HIAs, and were largely positive regarding the ability of HIAs to improve population health and health inequalities, but expressed procedural issues with their use, such as difficulties completing HIAs and a lack of knowledge of where to seek help. Staff outside of public health were much less aware of HIAs generally, and none knew whether HIAs were used in their organisation, but many supported their implementation. Interpretation: Despite low sample sizes, these results suggest that uptake of HIAs within local authorities may be patchy, and highlights a potential disconnect between local authority officers working within and outside of public health as regards understanding and knowledge of HIAs; this may impact the effectiveness of more widespread use of these tools. These data highlight the need for targeted training and capacity-building initiatives within local authorities, alongside the importance of organisational and political support. By addressing these challenges, local authorities could foster a more collaborative, health-oriented culture, contributing to improved health outcomes and reduced health inequalities across communities.