Tuning in to Kids® for parents of preschool-aged children in Portugal: study protocol for a randomized controlled trial

Abstract Background Childhood mental health (MH) problems are a major public health concern due to their high prevalence and well-documented adverse consequences, and are often under-recognized and untreated. Less effective parental emotion socialization practices play a critical role in the emergence of childhood MH problems, influencing children’s socioemotional development. Emotion-focused parenting programs, such as Tuning in to Kids ® (TIK), could be a promising approach to promote parents’ emotion coaching skills, enabling children to understand and regulate their emotions more effectively, while also supporting parents in managing their own emotions. Prior evidence supports TIK’s efficacy in improving children’s and parents’ MH outcomes across several countries; however, TIK’s efficacy has not yet been explored in Southern Europe. This study aims to provide a process and efficacy evaluation of TIK for parents of preschool-aged children in Portugal. Methods This trial is a parallel two-arm randomized clinical trial, which includes both process (i.e., feasibility and acceptability) and efficacy evaluation (i.e., change in primary and secondary outcomes and moderated effects) of Tuning in to Kids ® in Portugal. A minimum of 152 parents/legal guardians (> 18 years old) with at least one child between 3 and 6 years old will be enrolled. Parents will be randomly assigned to the intervention group or waiting list control group (76 per condition), through blocked randomization, with allocation concealment. Participants in both conditions will complete self-report questionnaires assessing primary (parental emotion socialization) and secondary (parents and children functioning dimensions) outcomes at baseline, post-intervention, and follow-up (2 months post-intervention). Longitudinal data will be analyzed using linear mixed-effects models accounting for repeated measures within participants. Discussion We anticipate that the Portuguese version of Tuning in to Kids ® will be feasible, acceptable and effective in improving parent emotion socialization (e.g., more adjusted parents’ beliefs and reactions to children’s emotions and emotion regulation skills), and parents’ and children’s psychological functioning (e.g., less parenting stress and reduced children’s emotional/behavioral difficulties). If achieved, these findings will support TIK’s use in promoting MH among families. Trial registration The clinical trial is registered at ClinicalTrials.gov (Identifier: NCT07350083, date assigned January 13, 2026).