Unpacking the associations between heterogeneous externalising symptom development and academic attainment in middle childhood.

This study explores children's externalising symptom development pathways between 8 and 11 years of age (three time points across 2 years) and examines their sociodemographic correlates and associations with change in academic attainment. Externalising symptoms were assessed for 5485 children across three consecutive years (M age = 8.7 years, SD = 0.30 at time 1). National standardised test scores served as an index of academic attainment. Using latent class growth analysis, six distinct trajectories of externalising symptom development were identified. Children who showed increasing externalising symptomatology across the three time points were more likely to be male or have special educational needs. These derived trajectories differentially predicted children's subsequent academic attainment (controlling for earlier attainment). Children with increasing externalising symptomatology were significantly more likely to demonstrate negative change in academic achievement compared with children with consistently low externalising problems. The study helps to clarify the longitudinal association between externalising symptom development and academic attainment, and highlights the importance of early intervention for children with increasing externalising symptoms across middle childhood.