Background and rationale

Substantial heterogeneity within, and overlap across, characteristics of children with neurodevelopmental conditions (NDCs) challenge traditional diagnostic classification systems. These shortcomings have driven a shift towards a transdiagnostic approach, focusing on shared characteristics and mechanisms across diagnoses to better understand complex neurodevelopmental profiles. Similar motor and self-regulatory behaviours have been widely observed in NDCs such as attention deficit hyperactivity disorder (ADHD), developmental coordination disorder (DCD), and autism spectrum disorder (ASD). Identifying these markers within the first three years of life could facilitate earlier identification of NDC likelihood, enhance understanding of children’s behaviours, reduce parental guilt and inform tailored caregiving. Additionally, it could support (personalised) early interventions for children, caregivers and teachers, ultimately improving long-term outcomes and reducing societal costs.  

Research questions

This study aims to investigate early motor and self-regulatory markers (0-3 years) predictive of later NDCs, specifically ADHD, ASD, and/or DCD. By integrating findings from a systematic review, a methodological study on movement quality and self-regulation assessment, parental perspectives and reported early markers, and a longitudinal follow-up study, this research seeks to enhance early identification within a transdiagnostic framework.

Method

A systematic review will synthesize evidence on early motor markers (0-3 years) linked to DCD, ASD and ADHD. Semi-structured interviews with 15 to 20 parents of children with these NDCs will explore parental perspectives within a transdiagnostic framework on early features, identification and intervention needs, analysed using inductive thematic analysis. A methodological study will develop an assessment method for movement quality and self-regulation, using structured coding and, if feasible, exploratory motion tracking in video recordings from BSID-III (5-36 months) and M-ABC (5 years) in 20 children with elevated NDC likelihood (TIARA study) and 20 controls. This method will be applied in a longitudinal follow-up of 175 children (TIARA cohort) to retrospectively analyse movement quality and self-regulation. At age eight, NDC diagnoses, and motor and psychological profiles will be evaluated. Developmental trajectories and the predictive value of these markers in relation to later NDC outcomes will be analysed using linear mixed models.