A Micro-Randomized Trial to Optimize a Just-in-Time Adaptive Intervention for Alcohol Craving and Suicide Ideation - PROJECT SUMMARY/ABSTRACT This K23 Mentored Patient-Oriented Research Career Development award (K23) will provide Dr. Margaret Baer with necessary skills to develop and optimize adaptive digital mental health interventions to improve treatment outcomes for patients with Alcohol Use Disorder (AUD) and with dual AUD and suicidal thoughts and behaviors (STB), a high-risk group with no existing integrated interventions. Launching this line of work requires new intensive training in clinical trials, digital mental health, adaptive intervention, and intervention optimization, a rigorous set of study designs that optimize treatments in their development phase. To gain this needed expertise, and to serve the needs of the AUD-STB population, the candidate proposes a mentored high-impact study to (1) develop a novel single-session intervention for craving and suicide ideation, and to (2) use a micro- randomized clinical trial (MRT) to collect the preliminary evidence (i.e., most promising intervention components and most promising delivery times) needed for a phone texting Just-in-Time Adaptive Intervention (JITAI) enhancing engagement with the skills learned in the single session intervention. This study has notable population health impact. Alcohol-attributed death (> 178,000 in 2020) and suicide (> 49,000 in 2023) are intertwined leading preventable causes of death, and up to 40% of people with AUD struggle with STB, increasing risk for both causes of death. Although AUD and STB have parallel proximal treatment targets (craving reduction and suicide ideation reduction, respectively) that are often addressed by brief planning interventions, up to 60% of patients have no skill-uptake following these brief planning interventions. Just-in-time adaptive interventions, or interventions that adapt based on real-time information, have moderate to high user engagement, and are a promising way to address low intervention uptake. This study therefore addresses the deficit in integrated intervention for AUD-STB by integrating two brief interventions into one telehealth single session planning intervention, with a four-week digital component. The study also addresses low planning intervention uptake by employing a micro-randomized clinical trial (MRT) to optimize text-message content and timing that can later be assembled into a JITAI. Hands-on training at the Medical University of South Carolina (MUSC) provided by a national mentorship team will ensure that Dr. Baer achieves the following career goals: 1) expertise in treatments and treatment needs for AUD and AUD-STB (Dr. Flanagan, Dr. Ilgen), 2) proficiency in the conduct, and evaluation of adaptive interventions for AUD using intervention optimization principles (Dr. Czyz), 3) proficiency in the conduct of clinical trials for AUD, including those focused on digital mental health (Drs. Flanagan, Ruggiero, Ilgen) 4) advanced training in data analysis of clinical trial data and intensive longitudinal data (Mr. Baker, Dr. Czyz) and 5) stronger skills in scientific communication and productivity (all mentors).