Commentary on Hobday et al. (2015): Inconsistent results beneath consistent conclusions—the need for a new approach to analysing alcohol availability

Abstract

Commentary on Hobday et al. (2015): Inconsistent results beneath consistent conclusions-the need for a new approach to analysing alcohol availability Alcohol availability studies keep producing unexpected findings alongside results that are in line with previous research. Such contradictory results should be seen as an opportunity for a renewed focus on theory development.More off-premise outlets are associated with fewer alcoholrelated injuries. Bar sales do not affect alcohol-related injury admissions. Areas with higher young male populations have lower levels of alcohol-related injury. These are some of the findings which do not feature in the conclusions of Hobday et al.'s well-executed analysis of the relationship between alcohol availability and alcohol-related injury [1]. What follows is not a criticism of the authors' work, which is good quality, offers useful findings on extended trading permits and merits its publication. Instead, we offer a reflection on a case study which is symptomatic of persistent problems in this area of alcohol policy analysis.Hobday et al. find evidence that the number of alcohol outlets in an area (in this case on-trade outlets and particularly those with extended trading permits) is associated positively with an outcome of interest to public health (in this case, night-time injury admissions to emergency departments). What the conclusions do not tell us is that, like many researchers before them, the authors' results tell an inconsistent story and, at times, are plain contrary [2]. From a policy perspective, the persistent identification of inconsistent findings is challenging and difficult to accommodate within compelling advocacy messages. It is easy to see why they are neglected. However, scientists should see such inconsistencies as a positive: they raise questions to be answered and a spur for new thinking.To their credit, Hobday et al. seek to examine their unexpected results, but their arguments are not always convincing. The economies of scale afforded by large off-trade outlets will probably prompt higher sales, but this does not explain why, after controlling for sales per outlet, a reduction in the number of off-trade outlets is associated with an increase in alcohol-related injuries. Perhaps drinkers are switching to the on-trade, a sector associated more closely with acute alcohol-related harm, but this explanation leads us to the puzzling finding that on-trade sales are unrelated to alcohol-related injury admissions. It is reasonable to conclude that increased on-trade outlet numbers are associated with increased injuries because the drawing together of crowds presents more opportunities for injuries to occur; however, public health researchers and advocates have long argued that intoxication levels are a partial cause of alcohol-related violence. Perhaps the lack of a relationship between on-trade sales per outlet and alcohol-related injuries is due to high sales outlets having more customers, rather than more intoxication. It may be that sales per outlet is a ...

Mapping Patterns and Trends in the Spatial Availability of Alcohol Using Low-Level Geographic Data: A Case Study in England 2003–2013

“…Similarly, given the strong links between area-level deprivation and health, an understanding of the relationship between deprivation and availability is critical public health intelligence and valuable for design, targeting and evaluations of interventions aiming to address the impact of changes in availability on health. A failure to fully capture some aspects of this complexity may partially explain some of the apparently conflicting findings in recent studies linking availability to harm outcomes [43,44]. For example, different subgroups of the population are likely to be affected in different ways by different forms of alcohol availability and the development of more specific, disaggregated measures of availability may help to better understand the complexity of the relationships between availability, alcohol consumption and harm.…”

Does your measure matter? A comparison of alcohol availability measures in Great Britain

“…Secondly, both different availability measures and different geographical areas can give very different pictures of socioeconomic outlet patterning and it may be that observed patterns in outlet distribution may arise from either the choice of measure or be specific to the location of study. These two findings may cast at least some light on recent concerns which have been raised about the consistency of results in availability research [5,6]. They also sound a major cautionary note on the transferability of the findings of availability research between different geographical contexts.…”