Pilot Trial of an Emotion Regulation and Executive Functioning Intervention for Self-Injurious Thoughts and Behaviors (SITBs) in Children

In Phase 1 of the study (Aim 1), the investigators will iteratively design an intervention for preadolescent SITBs through a step-by-step process using frameworks for systematically developing and adapting interventions (Wingood et al., 2008; Bartholomew et al., 1998). The design process will incorporate user-centered design methods, whereby multisectoral experts and end-users (i.e., therapists and families) will participate in the design process to maximize the intervention's dissemination and implementation potential. In Phase 2 of the study (Aims 2 and 3), the investigators will conduct a pilot randomized controlled trial (RCT) of the intervention, with a treatment as usual (TAU) comparator, in 52 preadolescents ages 7-12. Aim 2 will evaluate engagement (primary outcome), feasibility, acceptability, and implementation outcomes for the intervention and study procedures. Aim 3 will be to collect preliminary evidence to explore superiority of the SITB intervention to TAU in reducing SITBs and engaging the target mechanisms of EF and emotion regulation. In Phase 1, the investigators will use mixed methods approaches and user-centered design principles to iteratively develop the preadolescent SITB intervention. Through a needs assessment, the investigators will use an exploratory sequential qualitative--\> quantitative mixed methods design, whereby qualitative interviews with therapists will inform the development of a quantitative survey assessing needs and experiences of therapists treating preadolescents with SITBs. Results from the therapist assessment will be integrated with findings from qualitative interviews with preadolescents and caregiversto further inform initial decisions about core functions and specific components of the intervention. During a pre-testing phase utilizing a concurrent mixed methods approach, therapists and preadolescents/families will participate in think-aloud design sessions to provide quantitative and qualitative feedback about rough intervention prototypes. An initial draft of the intervention will then be produced and reviewed by a group of experts, resulting in a second draft of the intervention and therapist training and consultation procedures. A single-arm, pilot feasibility trial of the intervention with 9 preadolescents (ADAPT-ITT Step 8, Part 1) will inform adaptations to the intervention, therapist training, and trial procedures. Phase 2 will involve training therapists in the intervention, using procedures and materials refined during the pilot trial, followed by a RCT with a TAU control condition with 52 preadolescents (ADAPT-ITT Step 8, Part 2). The trial will be powered to detect differences in engagement between conditions (primary outcome) and establish feasibility and acceptability, while also evaluating preliminary efficacy outcomes and EF change mechanisms.