Project SPACE: Testing Daily Text Messages to Reduce Alcohol Use and HIV Risk Behavior

Project SPACE (Study Pilot on Alcohol Construals Everyday)

Project SPACE is a micro-randomized trial evaluating the proximal effects theory-based text messages on alcohol use and sexual HIV risk behaviors among HIV-negative young adult men at the day-level.

At baseline, all participants will complete GamePlan, an existing brief online sexual health program. During the subsequent 8-week intervention period, participants will complete a brief morning assessment of the preceding day and will be randomized each afternoon, with equal probability, to receive concrete ("how"), abstract ("why"), neutral control, or no afternoon intervention messages. Participants will also complete pre- and post-intervention measures. The effects of GamePlan are not being separately evaluated in this study.

Project SPACE will evaluate the proximal effects of different types of text messages on heavy drinking and HIV risk among young adult men. The study will evaluate the effects of the text messages on alcohol use and sexual HIV risk behaviors among young adult men. The study will evaluate the effectiveness of the text messages using responses obtained via online surveys and text messaging responses.

The study will enroll up to 240 young adult men aged 18-30 who report heavy drinking and HIV risk behaviors. No minors or other vulnerable populations are targeted. Recruitment will occur online nationwide through targeted digital outreach.

Participants will complete online pre- and post-intervention surveys. Following the baseline assessment, all participants will complete GamePlan, a brief online sexual-health program designed to help users reflect on their sexual and drinking choices, receive personalized feedback, and consider whether they wish to make changes. GamePlan is provided to all participants as a common baseline program and is not a randomized intervention component. The study is not designed to estimate the independent effect of GamePlan.

After completing the baseline assessment and GamePlan, participants will begin the 8-week daily text-messaging protocol. Each morning, participants will receive a brief assessment concerning alcohol use, sexual behavior, and related behaviors on the preceding day. At each afternoon decision point, participants will be independently randomized, with equal probability, to one of four conditions: CLT-concrete messages, CLT-abstract messages, neutral control messages, or no afternoon intervention messages.

In a small initial tech-check, up to 8 participants will participate to ensure surveys and text messages are functioning correctly and verify randomization procedures and data capture before full recruitment begins. The technical run-in is intended to permit operational refinements that do not alter the eligibility criteria, intervention content, randomization probabilities, outcome definitions, or assessment schedule.

Then, participants enrolled in the clinical trial will be involved for approximately 8 weeks, completing pre- and post-surveys alongside the texting intervention period.

No biological specimens will be collected. De-identified survey and intervention data may be stored securely and used for future research consistent with IRB approval.

The study team will protect participants' privacy and ensure the confidentiality of all data in accordance with Emory University's Office of Information Technology (OIT) data and security requirements. All study data will be stored on secure, password-protected servers, and access will be limited to authorized research personnel.

Inclusion Criteria:

• Male sex at birth and currently identify with male gender
• Own and use a smartphone that can receive text messages daily
• Have tested negative for HIV in the past 24 months
• Be willing to consider a change in their drinking behavior
• Not currently in a sexually exclusive relationship
• In the past three months, the subject must have had at least 3 condomless sexual encounters with men and consumes ≥5 standard alcoholic drinks at least once a week.

Exclusion Criteria:

• Involved in previous Project SPACE research (i.e., members of the Phase 1 community advisory board or Phase 2 pilot tests)
• Participants that have sought treatment for substance use in the past month.