The Best Start (Kia Timata Pai): A Study Protocol for a Cluster Randomized Trial with Early Childhood Teachers to Support Childrens Oral Language and Self-Regulation Development

IntroductionOral language skills are associated with childrens later self-regulation and academic skills; in turn, self-regulation in early childhood predicts successful functioning later in life. The primary objective of this study is to evaluate the separate and combined effectiveness of an oral language intervention (ENRICH) and a self-regulation intervention (ENGAGE) with early childhood teachers and parents for childrens oral language, self-regulation, and academic functioning. Methods and AnalysisThe Best Start study (Kia T[i]mata Pai in te reo M[a]ori, the indigenous language of New Zealand) is a cluster randomized controlled trial with teachers and children in approximately 140 early childhood centres in New Zealand. Centres are randomly assigned to receive either oral language intervention only (ENRICH), self-regulation intervention only (ENGAGE), both interventions (ENRICH + ENGAGE), or an active control condition. Teachers and parents practices and childrens oral language and self-regulation development are assessed at baseline at age 1.5 years and every 9-months to age 5, and academic performance at age 6. Teacher-child interactions will also be videotaped each year in a subset of the centres. Childrens brain and behavior development and parent-child interactions will be assessed every 6 months to age 6 years in a sub-group of volunteers. Ethics and DisseminationThe Best Start trial and the two sub-studies (Video Project; Brain and Behavior Development) have been approved by the University of Otago Health Ethics Committee (H20/116), and reviewed for cultural responsiveness by: the Ng[a]i Tahu Research Committee (University of Otago), the M[a]ori Advisory Group (University of Auckland, Liggins Institute) and an internal cultural advisory group. Results will be disseminated in international and national peer-reviewed academic journals and communicated to local, national, and international organizations serving early childhood teachers, parents, and young children. Trial registrationThis trial is registered with the Australian New Zealand Clinical Trial Registry (ANZCTR) as ACTRN12621000845831. Strengths and Limitations of This StudyO_LIStrength: The size and longitudinal design of this cluster RCT across early childhood will enable the assessment of the singular and combined effects of teacher-led oral language and self-regulation interventions on the development of childrens oral language, self-regulation, and academic functioning. C_LIO_LIStrength: The trial represents a partnership between a large provider of early childhood education (BestStart), an external implementation service (Methodist Mission Southern), and a consortium of academics (Emotion Regulation Aoetaroa/New Zealand) to provide a culturally responsive intervention with co-designed implementation with the early childhood education provider (BestStart); the use of a single national provider simplifies co-design and the implementation of the intervention. C_LIO_LIStrength: The efficacy of the interventions is assessed at multiple levels: via teacher and parent reports, behavioral observations, and measures of brain development (EEG/ERP). C_LIO_LILimitation: Because of the large size of the main trial, those assessments are restricted to teacher- and parent-report instruments. C_LIO_LILimitation: The single-provider feature with BestStart restricts the ability to collect primary outcomes on children who leave this service provider during early childhood. C_LI