Early Interventions in Children With Attention Deficit/Hyperactivity Disorder

Introduction: Attention deficit/hyperactivity disorder (ADHD) is one of the most prevalent mental disorders in children and is associated with important negative functional outcomes throughout development. The first signs and symptoms become apparent in preschool age. Therefore, early interventions in this population have the potential of limiting the disorder's negative impact and preventing future impairments in affected individuals. The first-choice medication for treating ADHD is methylphenidate, which has evidence of efficacy and safety in preschool children. However, non-evidence based worries and pressure from the media placed parent training as the first-line treatment for ADHD in clinical guidelines. Parent training is a behavioral intervention implemented with the parents, with weekly sessions for 8 weeks, adequate for treating ADHD dysfunctional symptoms and behaviors. However, the level of evidence for this intervention is reduced. Furthermore, the need of trained therapists in the public health system, added to the difficulties on adherence and comprehension from parents, limit its generalization and raise questions regarding its indications. Until now, no study has compared pharmacological treatment with methylphenidate to parent training in preschool children with ADHD regarding their clinical efficacy and cost-effectiveness. Moreover, no study has evaluated the impact of pharmacological intervention and psychotherapy on neurobiological mechanisms of ADHD, which is crucial for determining their impact on neurodevelopment. Objectives: This is a double-blind randomized clinical trial that aims to evaluate the efficacy, tolerability, and acceptability of treatment with methylphenidate compared to parental training and placebo in preschool children with ADHD. Methods: This study will be a randomized, double-blind, parallel-group, evaluating two active interventions and placebo control group. One hundred and fifty children aged 3 years and 11 months and