Preventing Drug Use Onset and Progression toward Addiction during a CriticalTransition Period: Optimizing an Online Intervention for High School Seniors - PROJECT SUMMARY/ABSTRACT The overall objective of the proposed research is to optimize a readily scalable online behavioral intervention that will prevent and reduce substance use (SU) among young adults. Rates of SU escalate rapidly after 12th grade among both college students and nonstudent young adults, peaking between ages 20-25 years, yet there are few preventive interventions for nonstudent young adults. Further, existing interventions for college students and nonstudent young adults occur after rates of SU jump. Thus, there is a critical need for new interventions that can prevent alcohol, tobacco, and marijuana use among young adults, as well as address the growing public health crisis of vaping. We will address this need by targeting high school seniors during a critical transition period. Our intervention is grounded in a developmental, social influences perspective and targets multiple social influences, which are the strongest predictors of SU among adolescents and young adults. Building on the success of past norms-based interventions, we propose using normative education in a novel way to change norms about bystander intervention strategies and norms about protective behavioral strategies. Further, we will use Human Centered Design (HCD) and the Multiphase Optimization Strategy (MOST) to iteratively engage key stakeholders in designing and strengthening the first ever optimized SU intervention for high school seniors. In addition, we will also test individual (e.g., demographic; behavioral characteristics) and contextual (e.g., social network and school characteristics) moderators of component efficacy. To increase the generalizability of our findings, we will recruit a diverse population of high school seniors, including those who do and do not plan to attend college, from over 50 high schools. Our Specific Aims are to: (1) design an initial set of six theory-based online intervention components targeting social influences linked to SU; (2) Evaluate the effect of each component on its targeted mediating variables using a fully powered cluster-randomized optimization trial (Trial I); (3) Revise less effective components; and 4) Evaluate the long-term efficacy of each revised component on its targeted mediators, SU, and secondary behavioral outcomes using a second cluster-randomized optimization trial (Trial II). By using HCD to identify and address stakeholders needs and by using MOST to evaluate individual intervention components, our research will result in an efficient, optimized, readily scalable SU intervention that can be quickly disseminated to high schools across the U.S. Our work will advance prevention science in three important ways: (1) We will demonstrate that a brief universal online intervention for high school seniors can prevent SU among young adults; (2) We will test several novel intervention strategies (i.e., using normative education to change norms about other behaviors linked to SU; targeting anticipatory socialization), allowing future researchers to create stronger, more efficient interventions; and (3) We will clarify how individual and contextual factors shape intervention responsiveness, allowing us to identify who needs additional, or different, intervention strategies.
