Mechanisms of Change Within a Short Psychological Intervention for Children With Eating Disorders ( SPICE ): A Qualitative Study

OBJECTIVE: Increasing numbers of young people (YP) are seeking support for eating disorders, creating a growing unmet need for timely and accessible treatment. While guided self-help (GSH) interventions have demonstrated effectiveness for other youth mental health difficulties, options for eating disorders remain limited. SPICE (Short Psychological Intervention for Children with Eating Disorders), a transdiagnostic CBT-based GSH program, was developed to address this gap. This qualitative study explored participant perspectives on the mechanisms through which SPICE may support recovery. METHOD: SPICE comprises eight weekly modules supported by a 30-min guided therapy session each week. Six female adolescents with eating disorders and their parents who completed SPICE participated in semi-structured post-intervention interviews. Data were analyzed using critical realist thematic analysis. RESULTS: Four key putative mechanisms were identified: (1) Interpersonal support (from the guide and parents) as a catalyst for change and for keeping momentum going. (2) Increased knowledge of eating disorders and associated cognitive and behavioural factors leading to positive changes. (3) In vivo experiential learning as key to implementing specific strategies and taking ownership over change. (4) Context, that is, individual and systemic factors promoting and inhibiting change. DISCUSSION: Interpersonal relationships were perceived to promote engagement and change. Participants reported that psychoeducation empowered them and their families, while experiential learning helped translate strategies into everyday practice. Flexible and tailored approaches were considered important for improving accessibility and effectiveness. Perceived barriers included complex module content, remote delivery, and competing commitments. Findings provide preliminary support for GSH interventions for eating disorders in YP and identify areas for refining future intervention.