Alcohol misuse is common in the Armed Forces (AF), with prevalence higher than in the general population. To date, initiatives to support alcohol misuse have focused on males, who represent ~90% of the AF. However, female veterans drink disproportionally more than female members of the public. In this study, the investigators will refine and evaluate DrinksRation - the only automated brief digital intervention supporting the United Kingdom (UK) Armed Forces to manage and reduce the amount they drink - to tailor the intervention to the specific needs of female veterans. The changes will then be assessed using a confirmatory Randomized Controlled Trial (RCT), which includes a minimum of 148 (74 in each arm) female veterans (to be recruited).

There are 2.5 million AF veterans in the UK (defined by the British Government as those who have served in the military for at least one paid day), of which 11% are estimated to identify as female. Female veterans have served within the AF for over 100 years. While their valuable contribution has been recognized, military culture, together with evolving Service requirements, have had a significant impact on the health and well-being of many. Yet, there is a dearth of evidence on the impact of alcohol use on female veteran health.

The limited existing evidence suggests that female veterans' alcohol use is increasing and that they are significantly more likely to report symptoms of hazardous drinking when compared with female civilians. Increased rates of hazardous drinking were also observed by Palmer and colleagues (202), who found that half (49%; n=389 of 779 female veterans) were misusing alcohol at a hazardous or higher level which is considered harmful to their health. To place this into context, the UK Chief Medical Officer recommends that everyone does not regularly drink more than 14 units per week, to keep health risks from drinking alcohol to a low level.

Alcohol misuse often co-occurs with common mental health disorders including PTSD, anxiety, or depression, and alcohol is frequently used as a coping mechanism. Common mental health disorders are more common in females than male veterans. Research has also shown that female veterans face barriers to accessing mental health support, often due to misusing alcohol. Ultimately, while female veterans drink less than male veterans, their rates of hazardous drinking are higher than the general population putting them at increased risk of poorer health.

The impact of alcohol misuse among female veterans on the wider society (e.g. health care utilization, productivity, and welfare) is unknown. In England, heavy drinking (deemed as drinking more than 14 units of alcohol per week) is estimated to cost the National Health Service (NHS) £3.5 billion per year (3.6% of its annual budget) and is more common in people with mental health difficulties, Since female veterans drink more than their civilian counterparts, the relative costs are likely to be even higher. Innovative solutions are urgently required.

In recent years there has been a growing treatment gap in the UK, with patients waiting longer for treatment and support for alcohol misuse. To overcome this gap, the investigators developed the DrinksRation platform (www.drinksration.app), an automated brief digital intervention designed to support help-seeking veterans in managing and reducing the amount they drink. DrinksRation is unique in that the app content is tailored using behaviour change techniques to promote positive changes in behaviour. DrinksRation is the only app targeting alcohol misuse in the UK AF. It is designed to (1) overcome geographical limitations; (2) use wearable technology (e.g. Fitbit, Apple Watch) to inform decision-making and personalization; (3) avoid the stigma associated with receiving help in person; and (4) provide convenience since users can use the app as they prefer (discretely or openly). The app is freely available via Apple and Google App stores. The app has received support and endorsement from Combat Stress and is currently being trialled in serving personnel. DrinksRation is supported by a robust evidence base, including a randomized controlled trial which demonstrated that the app is efficacious in reducing alcohol consumption.

The DrinksRation app was developed to support veterans who have sought help for a mental health problem and was not designed with potential gender differences in mind. A recent viewpoint highlighted a critical need for feminist intersectionality in digital health to incorporate the unique needs of females. Digital health technologies can bolster gender equality through increased access to healthcare, empowerment of one's health data, overcoming the specific barriers facing female veterans, and reducing the burden on healthcare systems.

This project aims to tailor the DrinksRation app to reflect the specific needs of female veterans and evaluate these changes using a confirmatory randomized controlled trial. It is hypothesized that a refined version of DrinksRation will be efficacious at reducing self-reported weekly alcohol consumption between baseline and 3-month follow-up (day 84) among female veterans who drink at a hazardous or harmful level.

Inclusion criteria

• Are aged 18 years or older;
• Identify as female (self-reported sex);
• Live in the United Kingdom;
• Consume 15 UK units (approximately 150g) of alcohol or more per week as measured using Timeline Follow-back for alcohol consumption (TLFB; [23]) at baseline (day 0);
• Are veterans of the UK AF, defined as per UK definitions as having completed at least one day of paid employment in the UK AF (verified by self-report at eligibility screening);
• Have downloaded the mobile app onto an iOS or Android smartphone.

Exclusion criteria

-Does not own a smartphone phone.

Identify as female (self-reported sex);

All study data will be made available in an anonymized format alongside any source code via the Open Science Framework. There are no contractual agreements that limit access or sharing of data.

Upon publication of the main study report.

None required.

Researcher DL and GW will be unblinded to treatment allocation to enable the management of the BeAlcoholSmart and DrinksRation platforms and participant recruitment and retention; researcher EC will be unblinded to treatment allocation to prepare statistical reports. Researcher DL and EC will not be involved in participant engagement. All other members of the study team will be blind to treatment allocation.