What is the effectiveness of the DrinksRation smartphone application on modifying alcohol use behaviour in Service personnel at risk of alcohol-related harm?

INTERVENTION: This study is a two‐arm randomised controlled trial comparing the Drinks:Ration smartphone application with usual care. Participants will be recruited through periodic dental inspections, Service specific communications and social media, and through poster advertisements for the trial in military establishments. Participants will be recruited if they are current serving UK military and willing to be sent surveys to study their drinking behaviours, health and wellbeing. Initial screening with AUDIT‐C will define eligibility for the trial arms. Participants with an AUDIT‐C score of =5 will be eligible for the Drinks:Ration RCT. Those scoring =4 on AUDIT‐C will not be eligible for the RCT but will still be able to partake in the surveys (see data gathering group below). Randomisation will occur automatically using the Research Electronic Data Capture (REDCap) research management programme31 after participants have read the participant information leaflet, consented to inclusion and completed basic demographics. Two participant blocks in a 1:1 ratio will be used to ensure equal gender distribution between the control and intervention arms. The REDCap randomisation module will be programmed, by the RCI / University of Birmingham statistician, independently of the research team to maintain blinding to participant treatment allocation. Participants will be blinded to the intervention as they will be told that the research involves them completing various surveys about drinking behaviours, health and wellbeing. The intervention arm will be emailed copies of the relevant trial information leaflets and a link to download the Drinks:Ration app. They will be asked to use the app for a minimum of 28 days. The contro CONDITION: Alcohol behaviour change in military personnel identified as being at risk of alcohol related harm. ; Not Applicable PRIMARY OUTCOME: Change in alcohol units consumed per week between baseline and day 84 as measured by the timeline follow back method. INCLUSION CRITERIA: 1. Age 16 years ‐ no upper limit (upper age limited by being in active military service) 2. Serving UK Military 3. Scores 5 or more on AUDIT‐C screening questionnaire SECONDARY OUTCOME: ; 1. Change in alcohol units consumed per week between baseline and day 168 as measured by the timeline follow back method.; 2. Change in AUDIT score between baseline and day 84.; 3.1. Change in quality of life assessment between baseline and day 84 as measured by World Health Organisation Quality of Life‐BREF survey.; 3.2. Change in quality of life assessment between baseline and day 168 as measured by World Health Organisation Quality of Life‐BREF survey.; 4. Change in drinking motivations between baseline and day 84 as measured by the Drinking Motivations Questionnaire (Revised).; 5.1. Change in mental health screening parameters (depression, anxiety, PTSD) between baseline and day 84.; 5.2. Change in mental health screening parameters (depression, anxiety, PTSD) between baseline and day 168.; 6. Assessment of correlation between alcohol intake and loneliness (De Jong Gierveld), recent life events (RLE‐Q), gambling behaviours (GMQ‐9), domestic & sexual assault (National Crime Survey for England & Wales).;