A Metacognitive Intervention for Children and Adolescents in Neuropediatric Care (Mio-Training): Protocol for a Randomized Controlled Trial.

Background: Diseases during childhood and adolescence such as cancer or attention-deficit/hyperactivity disorder (ADHD) can have an impact on brain development and place children and adolescents at increased risk for cognitive long-term problems. Most cognitive trainings currently available have limited efficacy and show limited transfer to nontrained tasks and everyday functioning. We developed a novel intervention (Mio-Training) aiming to increase metacognitive abilities at the intersection between exercise psychology and cognitive science to strengthen the cognitive development of pediatric patients with atypical brain development in the long term. Objective: The study assesses the efficacy of the Mio-Training on the primary (metacognitive abilities) and secondary outcomes (executive functions, processing speed, and memory) before the training, immediately after the training, and at a 3-month follow-up in patients with atypical development and healthy controls. Methods: The Mio-Training stimulates metacognition through 38 digital games, which playfully teach mnemonic strategies (ie, rehearsal, chaining, and associations), present intensive verbal and visual working memory training, and motor coordination tasks. The training group will train for 5 weeks, 3 times per week, for 20 minutes. The waiting control group will receive the training after completion of the study procedure. We will evaluate the efficacy of the Mio-Training on metacognitive abilities and cognitive performance in a randomized controlled clinical trial. We expect a long-term increase in metacognitive abilities associated with an increase in subjective and objective cognitive performance. The efficacy of the Mio-Training will be investigated in 3 subgroups (patients with cancer, ADHD, and healthy controls; each group n=40; all aged 8-16 years) using pre-intervention and post-intervention assessments. All participants will be randomly assigned to the Mio-Training or the waiting control group, stratified by age and sex. Results: This study protocol describes the study design of the randomized controlled trial evaluating the efficacy of the Mio-Training. The project is funded from October 2024 to December 2027. Recruitment for healthy controls has been completed (n=40; October 2024-August 2025), recruitment for childhood cancer survivors (n=10, 25% participants recruited) is scheduled from August 2025 to December 2027, and recruitment for participants with ADHD (n=39, 97.5% recruited) is scheduled from October 2025 to September 2026. Data analyses have not yet commenced; first results from the ADHD subgroup are expected in early 2027, with findings from the cancer survivor subgroup anticipated in early 2028 following completion of recruitment. Conclusions: To strengthen cognitive development in young patients with atypical development, it is necessary to address the current lack of effective treatment options. The combination of cognitive and motor training with metacognitive abilities may support patients' cognitive maturation trajectories and will enable transfer of the training effect to everyday and school situations.