The purpose of this study is to test the feasibility and acceptability of an innovative mobile application (uSafeUS+) to reduce college student drinking and sexual assault (SA) risk in real time. Following an initial period of app development, this study will use a pilot 3-arm randomized controlled trial (N = 90; 30/arm) to examine the acceptability, feasibility, and initial evidence of efficacy of the novel, expanded uSafeUS+ app, relative to the existing SA-only focused uSafeUS app (already in use on 24 college campuses), and an assessment-only control condition.

Specifically, the investigators aim to answer the following research questions:

1. Do students like the app (overall and specific features)?
2. How frequently do students use the app within the 1-month exposure period?
3. What barriers and facilitators impact app use?
4. Is there evidence of increased use of protective behaviors on drinking days and over time?
5. Is there evidence of decreased drinking (amount, frequency) or SA risk on drinking days and over time?

Participants will complete:

• A baseline assessment
• A 1-month app exposure period with daily surveys about app use on the weekends
• Follow-up surveys at 1- and 2-months post-intervention.

Over 75% of campus sexual assaults involve alcohol, yet existing campus alcohol and SA prevention efforts designed for universal delivery are often siloed and limited in their ability to provide students with in-the-moment assistance to reduce risk. Smartphone apps are an integral part of college student life and are increasingly used to engage students in real-time alcohol prevention; however, none have integrated alcohol and sexual assault prevention into a single cross-cutting tool. This study addresses this gap by expanding a promising campus sexual assault prevention and response app (uSafeUS®) to include evidence-based alcohol harm reduction tools and real-time messaging to support students' use of protective behavioral strategies (PBS) in the moments when they most need them. The uSafeUS app, currently in use on 24 US college campuses, utilizes sexual assault PBS (e.g., sharing current locations and an expected return home time with trusted peers) as the primary risk reduction mechanism for students to use in social contexts where alcohol is present, yet none of the existing features directly address alcohol consumption. This project will leverage the existing uSafeUS infrastructure and a proven user-centered development process to expand app features to include an interactive drink tracker and personalized feedback messaging to reduce alcohol consumption and increase PBS use (uSafeUS+).

Following app development, the investigators will conduct a 3-arm pilot randomized controlled trial (N = 90) using an intensive longitudinal design to test uSafeUS+, relative to active (uSafeUS) and assessment-only control groups. Long term, uSafeUS+ is expected to reduce drinking outcomes and SA risk at 3-month follow-up by increasing PBS use and decreasing the amount students drink on days when students use PBS app features. This study will establish the feasibility and acceptability of uSafeUS+ and our proposed event-level evaluation approach, which is innovative and necessary to examine both between-group differences in behavioral outcomes over time and within-person variability in app feature use, acceptability, and behavioral outcomes across app use days, relative to non-app use days.

Specifically, the investigators will examine: a) app evaluability and evaluation plan feasibility using enrollment, retention, compliance, and app use data; b) overall acceptability of the app and evaluation procedures, including event-level variability in app acceptability during a 1-month app exposure period; c) psychometric properties of evaluation instruments; and d) preliminary effect sizes of app impacts on drinking and PBS use at the event level (via weekend daily diaries; uSafeUS+ vs. uSafeUS), and SA risk outcomes over time (1- and 2-month follow up; uSafeUS+ vs. uSafeUS + assessment-only control).

Participants will complete a baseline survey, which will determine participant eligibility, randomly assign students to conditions, and assess prior drinking behaviors, protective behavior use, and sexual assault experiences. Students in the uSafeUS+ or uSafeUS groups will be trained in using their assigned app and the daily survey protocols, followed by a 1-month app exposure period with integrated weekend daily diary assessments of event-level app feature acceptability, use context (where they were, who they were with), and outcomes (e.g., daily drinking, protective behavior use). The investigators will also passively collect embedded metadata on daily app usage. All students, regardless of group assignment, will complete 1- and 2-month drinking and SA risk surveys.

Inclusion Criteria:

• Participants must be between the ages of 18 and 25 years old;
• Currently enrolled as a residential undergraduate student at a participating university;
• Intend to reside on or near (in the same town) campus over the two-month study period
• Own a smartphone/mobile device;
• Have consumed at least one alcoholic beverage per week or engaged in dating or social behaviors where alcohol is present at least once a week over the past 30 days;
• Intend to drink or go out at the same frequency (at least weekly) over the two-month study period

Exclusion Criteria:

• Unable or unwilling to provide informed consent

Deidentified data from the baseline, daily diary, and follow-up assessments will be shared per NIH requirements established through the negotiated data sharing agreement.

Data will be shared via the NIAAA data archive starting 10/1/2026 for as long as NIH keeps the archive active.

Per the signed DSA, data and supporting will be available upon reasonable request via the NIAAA data archive.