Higher-Order Dimensions of Psychopathology in a Neurodevelopmental Transdiagnostic Sample

Hierarchical dimensional models of psychopathology derived for adult and child community populations offer more informative and efficient methods for assessing and treating symptoms of mental ill health than traditional diagnostic approaches. It is not yet clear how many dimensions should be included in models for youth with neurodevelopmental conditions. The aim of this study was to delineate the hierarchical dimensional structure of psychopathology in a transdiagnostic sample of children and adolescents with learning-related problems, and to test the concurrent predictive value of the model for clinically, socially and educationally relevant outcomes. A sample of N=403 participants from the Centre for Attention Learning and Memory (CALM) cohort were included. Hierarchical factor analysis delineated dimensions of psychopathology from ratings on the Conner’s Parent Rating Short Form, the Revised Children’s Anxiety and Depression Scale, and the Strengths and Difficulties Questionnaire. A hierarchical structure with a general p factor at the apex, broad internalising and broad externalising spectra below, and three more specific factors (specific internalising, social maladjustment, and neurodevelopmental) emerged. The p factor predicted all concurrently measured social, clinical and educational outcomes, but the other dimensions provided incremental predictive value. The neurodevelopmental dimension, which captured symptoms of inattention, hyperactivity and executive function and emerged from the higher-order externalising factor, was the strongest predictor of learning. This suggests that in struggling learners, cognitive and affective behaviours may interact to influence learning outcomes. Keywords: neurodevelopmental; transdiagnostic; childhood psychopathology; general p factor; hierarchical dimensional model General Scientific Summary: This study identifies dimensions of psychopathology in a sample of children with neurodevelopmental difficulties who are at increased risk for mental health problems. Dimensions capturing neurodevelopmental concerns were the strongest predictors of the children’s current learning outcomes.