Protocol for a systematic review and network meta-analysis of randomised controlled trials examining the effectiveness of early parenting interventions in preventing internalising problems in children and adolescents.

Abstract Background: Internalising problems, such as depression and anxiety, are common and represent an important economical and societal burden. The effectiveness of parenting interventions in reducing risk of internalising problems in children and adolescents has not yet been summarised. The aims of this review are to:1. assess the effectiveness of parenting interventions in the primary, secondary and tertiary prevention of internalising problems in children and adolescents;2. determine which intervention components and which intervention aspects are most effective for reducing risk of internalising problems in children and adolescents. Methods: Electronic searches in OVID SP versions of Medline, EMBASE and PsycINFO; Cochrane Central Register of Controlled Trials; EBSCO version of ERIC and clinicaltrials.gov have been performed to identify randomised controlled trials or quasi-randomised controlled trials of parenting interventions. At least two independent researchers will assess studies for inclusion and extract data from each paper. The risk of bias assessment will be conducted independently by two reviewers using the Cochrane Collaboration’s Risk of Bias Assessment Tool. Statistical heterogeneity is anticipated given potential variation in participant characteristics, intervention type and mode of delivery, and outcome measures. Random effects models, assuming a common between-study variability, will be used to account for statistical heterogeneity. Results will be analysed using a network meta-analysis (NMA). If appropriate, we will also conduct a component-level NMA, where the ‘active ingredients’ of interventions are modelled using a network meta-regression approach.Discussion: Preventing and reducing internalising problems could have major beneficial effects at the economic and societal level. Informing policy makers on the effectiveness of parenting interventions and on which intervention’s component is driving the effect is important for the development of treatment strategies. Systematic review registration: International Prospective Register for Systematic Reviews (PROSPERO) number CRD42020172251