Behaviour change techniques in popular alcohol reduction apps

Background Smartphone apps have the potential to reduce excessive alcohol consumption cost-effectively. Although hundreds of alcohol-related apps are available there is little information about the behaviour change techniques (BCTs) they contain, or the extent to which they are based on evidence or theory and how this relates to their popularity and user ratings. Objectives To assess the proportion of popular alcohol-related apps available in the UK that focus on alcohol reduction, identify the BCTs they contain and explore whether BCTs or the mention of theory or evidence is associated with app popularity and user ratings. Method The iTunes and Google Play stores were searched with the terms ‘alcohol’ and ‘drink’ and the first 800 results were classified into: alcohol reduction, entertainment or blood alcohol content measurement. Of those classified as alcohol reduction, all free apps and the top 10 paid apps were coded for BCTs and for reference to evidence or theory. Measures of popularity and user ratings were extracted. Results Of the 800 apps identified, 662 were unique. Of these, 13.7% were classified as alcohol reduction (n=91, 95% CI: 11.3 – 16.6), 53.9% entertainment (n=357, 95% CI: 50.1 – 57.7), 18.9% blood alcohol content measurement (n=125, 95% CI: 16.1 – 22.0) and 13.4% other (n=89, 95% CI: 11.1 – 16.3). The 51 free alcohol reduction apps and the top 10 paid apps contained a mean of 3.6 BCTs (SD=3.4), with approximately 12% (7/61) not including any BCTs. The BCTs used most often were: ‘facilitate self-recording’ (54.1%), ‘provide information on consequences of excessive alcohol use and drinking cessation’ (42.6%), ‘provide feedback on performance’ (41.0%), ‘give options for additional and later support’ (24.6%) and ‘offer/direct towards appropriate written materials’ (23.0%). These apps also rarely included any of the 22 BCTs frequently used in other health behaviour change interventions (mean: 2.46, SD = 2.06). Evidence was mentioned by 16.4% of apps and theory was not mentioned by any app. Multivariable regression showed that apps including advice on environmental restructuring were associated with lower user ratings (Β = -46.61, p = .04, 95% CI: -91.77 – -1.45) and that both the techniques of ‘advise on/facilitate the use of social support’ (Β = 2549.21, p = .04, 95% CI: 96.75 – 5001.67) and the mention of evidence (Β = 1376.74, p = .02, 95%, CI: 208.62 – 2544.86) were associated with the popularity of the app. Conclusions Only a minority of alcohol-related apps promoted health while the majority implicitly or explicitly promoted the use of alcohol. Alcohol-related apps that promoted health contained few BCTs and none referred to theory. The mention of evidence was associated with more popular apps, but popularity and user ratings were only weakly associated with the BCT content