Pilot PEACE: A pilot hybrid optimization-implementation trial of strategies to protect and promote children's mental health amid post-separation/divorce interparental conflict - Project Summary/Abstract This proposal addresses the significant public health concern of destructive interparental conflict (IPC), which is strongly associated with a range of adverse outcomes for children, including mental health disorders, substance use, academic challenges, risky behaviors, and suicidality. These effects are particularly pronounced in the context of parental separation and divorce, which impacts over half of U.S. children by age 15. Family courts frequently interact with families experiencing high levels of IPC, making them critical settings for implementing interventions aimed at reducing these negative outcomes. However, most parenting programs mandated or referred by family courts are not evidence-based, leaving a critical gap in effective support for families experiencing high IPC. This pilot study aims to address this gap by evaluating the feasibility, acceptability, and preliminary impact of intervention components designed to mitigate the effects of IPC on children’s mental health. Using the Multiphase Optimization Strategy (MOST) framework, we will pilot a highly efficient experimental trial design (N = 96) to gather preliminary data on five candidate intervention components: high- versus low-intensity delivery of IPC reduction approaches, inclusion of constructive IPC skills, inclusion of IPC resolution skills, inclusion of skills for repairing parent-child relationships after IPC events, and high- versus low-intensity home practice support. These components were selected based on empirical support for their potential to reduce child mental health problems. The findings from this pilot study will inform the design of a future fully powered trial to identify the most effective and scalable combination of components that can be delivered within the practical constraints of family courts. In Aim 1, we will assess the feasibility of recruitment, randomization, and trial procedures, and the acceptability of intervention components among parents and family courts. Quantitative and qualitative feedback will guide refinements to the components and trial design. In Aim 2, we will explore the components’ preliminary impact on children’s mental health using validated measures and explore hypothesized mechanisms of action, including quality of parents’ home practice and children’s emotional security. These findings will help refine the intervention’s conceptual model. In Aim 3, we will identify potential implementation barriers and facilitators by conducting qualitative interviews with judges and court administrators from three family courts of varying resources and sizes. Using the Consolidated Framework for Implementation Research (CFIR) and the Expert Recommendations for Implementing Change (ERIC), we will develop an Implementation Research Logic Model (IRLM) to guide scale-up planning for the fully powered trial. This pilot study will lay the foundation for a scalable and effective intervention addressing IPC, leveraging family courts as a key implementation context. The future fully powered trial will advance the development of effective, evidence-based parenting programs that improve children’s mental health outcomes in the aftermath of parental separation/divorce.