Collaborative to understand impacts of early preventive interventions on suicide and overdose mortality using data harmonization methodology - Project Summary The goal of this application, submitted in response to RFA-MH-23-275, “Using Secondary Data Analysis to Determine Whether Preventive Interventions Implemented Earlier in Life Reduce Suicide Risk,” is to conduct research that will integrate and harmonize existing large prevention trial datasets. The included randomized clinical trials (RCT) were delivered before adulthood (prior to age 18) and did not explicitly target suicidal thoughts and behaviors (STB). Each RCT consists of well-characterized participant-level prospective data with consent that allows for the harmonized data to be submitted to the NIMH Data Archive and allows for National Death Index searches. This study will examine ‘cross-over effects’ (e.g., unanticipated beneficial effects) of the RCTs in reducing risk for later fatal and nonfatal STB, and related outcomes such as overdose, Substance Use Disorders (SUD), Opioid Use Disorders (OUD), accidents, and all-cause mortality. This U01 proposal has obtained 29 existing prevention trial data sets with collaboration of the principal investigators and data custodians who have rights to the original data. We will de-identify, aggregate, and harmonize the prevention trial datasets and utilize advanced computational/analytic strategies to examine whether intervening early reduces the risk for STB and related outcomes. We will identify the most potent aspects by examining the various components of each intervention as well as the proximal and distal targets, format, setting, dose/duration, developmental timing, and quality of implementation. Potential mediators and mechanisms of action (e.g., aspects of parenting, social factors, emotional and behavioral regulation) will also be studied and identified. This effort will examine moderators of the effects of preventive interventions, including specific subpopulations (e.g., individuals from historically minoritized and socioeconomically disadvantaged backgrounds), and those individuals experiencing initial elevated levels of risk (e.g., systems-involved youth, youth who had experienced early trauma/adverse childhood events). Data will be utilized from 29 trials involving 14 programs and 42,509 individuals. With over 40,000 participants across all studies, harmonizing data will allow for more complex, multifactorial, multi-level analyses to explore intervention impacts on fatal and nonfatal STB and related outcomes as well as potential mediators, mechanisms, and moderators of impact. The U01 team will oversee the preparation of a final harmonized prevention trial dataset to be deposited to the NIMH Data Archive (NDA) with data dictionaries and associated documentation from the original studies. This project has the potential to inform the refinement and development of future preventive intervention strategies delivered early and scaled to address suicide and overdose in the US.