Prevention of internalizing difficulties in the middle years: Protocol for a noninferiority randomized trial of Mindfulness-Based Cognitive Therapy for Children and Cognitive Behavioural Therapy

Aim: Mindfulness-based interventions have been tested as preventive programs for childhood internalizing difficulties, but most research has been at a 'universal' level with small to null effects. Mindfulness-Based Cognitive Therapy for Children (MBCT-C) has similar effects to Cognitive Behaviour Therapy (CBT) when used as a small-group, targeted preventive program. Knowledge gaps include the longer-term effectiveness of MBCT-C relative to CBT and the benefits of adding a parent module. This trial aims to compare MCBT-C to traditional CBT, including a parent module, to 15-months post-intervention and to test the feasibility and acceptability of adding a parent module. Methods: Participants will be recruited from primary schools in areas of socio-economic disadvantage in South Australia (n = 194). Children (aged 9-12) years with signs of internalizing difficulties (e.g., shy, withdrawn, worried), and their parents, will be eligible for this two-armed randomized controlled non-inferiority trial (RCT). Children will participate in 10 group sessions of MBCT-C or CBT, facilitated by psychologists, and parents from both conditions will participate in two parent-only group sessions. Child self-report measures include depression and anxiety, as well as attention, mindfulness and self-compassion. Parent measures include symptoms of depression and anxiety, mindfulness, and parent-child relationship strength. The primary outcome will be child anxiety and depression (Revised Child Anxiety and Depression Scale-25). Measures will be collected pre and post intervention, and at 3, 6, 12 and 15-month follow up. Results: Schools will be recruited from October 2022. Nomination of children will commence from February 2023. Program implementation will begin May 2023. Conclusions: This trial will have implications for the feasibility of involving parents in preventative programs, as well as whether mindfulness-based interventions prevent internalizing difficulties over time.