Discussion
We undertook a systematic review to identify and synthesise the current evidence base on the impact of local alcohol licensing decisions. Given the potential for these decisions to have a measurable impact on health and related outcomes in the local population, and the involvement of local public health teams in licensing decisions, it is important to understand the extent to which changes to local licensing policy may represent an effective public health intervention. We identified seven papers based on quantitative evaluation of local alcohol policy approaches.
The studies used quasi-experimental designs including natural experiments, some with local comparator areas and others employing the use of synthetic controls. In natural experiment studies, the exposure allocation is not controlled by researchers but is assumed to be ‘as-if randomised’.27 As these studies evaluate the impact of events or process that leads to differences in exposure, they are potentially less susceptible to bias than other observational study designs.27 However, the studies with synthetic controls are challenging to conduct over long time scales, with uncertainty around the synthetic measures increasing over time as these are static measures, and therefore, become less reliable over time. As naturally occurring populations also contain significant variance, the difficulties in identifying the most appropriate control populations also renders the use of naturally occurring comparison groups problematic. Although propensity scoring methods could be used to find ‘best matches’, synthetic controls may be particularly useful when suitable comparison groups are not available. There is a challenge over all in clear defining and differentiating the study designs employed.
Some limited changes in health and crime-related outcomes as a result of local intervention were noted but were often reversed over a longer timeframe and most changes were not significant overall. In terms of statistically significant changes in health outcomes, de Vocht et al22 reported that higher intensity local licensing policy (CIZ and increased licensing enforcement) was associated with a 2% decrease in hospital admission rates annually, and de Vocht et al23 reported an effect of changing from ‘passive’ alcohol licensing intensity to ‘most intense’ on alcohol-related hospital admissions. In addition, de Vocht et al24 reported a significant reduction in antisocial behaviour for one case study only, and Pliakas et al21 reported some significant reductions in overall crime.
Overall, there is very little evidence to directly link local decisions in alcohol licensing to consistent or sustained changes to health or crime outcomes downstream. This is disappointing given that complementary qualitative evidence indicates that local public health teams can provide valued input into alcohol licensing in ways which had been expected to facilitate reductions in alcohol harms.28 While the engagement of local authority public health teams in alcohol licensing decisions may influence those licensing decisions successfully, the changes may still not influence health outcomes due to the limited capacity (and therefore impact) of local decisions vs national policies.
It is important to consider the use of novel methods including synthetic control areas within the natural experiments undertaken. The method makes assumptions that the relationship between the control and the intervention areas is stable,23 which is unlikely in reality. However, confounders such as national policies or austerity that affect all time series, will automatically be controlled for.23 This, along with relatively large samples sizes, suggests that if there was an important effect these methods would identify it, and therefore, it is reasonable to conclude there is no evidence of an effect.
The mechanisms by which changes in alcohol availability may impact on alcohol-related harms are poorly examined and understood11 with greater clarity needed as to how changes in temporal and physical alcohol availability impact on alcohol consumption choices and patterns. Despite the involvement of stakeholders from all four of the UK home nations, the studies that we identified were all conducted in England, with the exception of de Vocht et al25 which also included data from Scotland. Given that alcohol policy approaches vary significantly in Wales, Scotland and especially Northern Ireland (with significantly different licensing systems in place), it is not possible to generalise from studies conducted in England to those nations.
Conversations with our stakeholders support the argument that public health practitioners with responsibility for alcohol licensing decisions can have only a limited positive impact in terms of encouraging the consideration of health outcomes and health data within decision-making. As noted by the study authors themselves, such involvement likely has benefits in shaping the licensing system to take account of health issues longer term, but it is unrealistic to expect this to directly impact on measurable outcomes in health, well-being or crime over the time frames implemented in these studies.23 With CIZ only able to impact on new licensing decisions, the influences which can be exerted will always be dwarfed by the impact of alcohol outlets which already exist. The impact of local licensing decisions is further limited by the boom in online alcohol sales and rapid doorstep deliveries.23 It may simply be that regardless of the extent of public health involvement, the impact of local licensing decisions is not substantial enough to lead to changes in harms of a detectable magnitude.
Study limitations
Our systematic review design was limited by the time frame in which we were required, by our funders, to complete the review process, leading to a rapid review methodology being selected. However, the limited evidence base identified gave us more time to ensure that our searches were exhaustive (including grey literature sources) which, alongside the thorough application of both additional searching techniques and stakeholder consultation, reassures us that further evidence sources have not been missed. Our review focused on the UK evidence as it was commissioned by a UK funder. Our searches (including initial scoping searches without a UK filter applied) did, however, suggest that there was no significant volume of evidence from other countries. With more time and resources, potentially relevant further international evidence may have been identified, however, the particular context of the UK licensing arrangements would render it less relevant to our specific review question.
Conclusions
We identified a small volume of evidence regarding the health (and related) impacts of alcohol licensing decision undertaken in local authorities. Despite relatively sophisticated study designs and some longer-term analysis, the evidence we identified did not demonstrate a consistent or sustained association between local decisions in alcohol licensing and health or crime outcomes downstream. It seems unlikely that the lack of measurable or consistent effects is purely due to the choice of study design or methods of analysis. Given that the impacts of local decisions are currently limited, greater regulatory powers are needed if local licensing interventions are to be an effective intervention to reduce alcohol-related harms. It is, therefore, unlikely that simply conducted more research of the type identified in this review (at least in England and Wales) would be beneficial, without first making regulatory changes to strengthening the impact of local decisions.