Beyond the Diagnostic Label: Data-Driven Characterisation of Cognitive and Mental Health Profiles in a Transdiagnostic Sample of Neurodivergent Adults

Neurodiverse diagnoses (NDs) have been largely conceptualised as distinct categories with clear-cut diagnostic boundaries. Converging research evidence, however, is showing that this conventional approach inadequately captures the individual variation and overlaps that are commonly manifest. This study aimed to build upon emerging quantitative research frameworks for understanding diagnostic complexity, through adopting a transdiagnostic dimensional approach toward characterising the cognitive and mental health dimensions associated with NDs. A cohort of 175 adults, who had been referred for assessment and/or sought help from community support services in the UK for suspected or previously diagnosed neurodiverse conditions, were recruited using convenience sampling. Cognitive domains of executive function, language, attention, processing speed and memory were measured using the National Institute of Health (NIH) Cognition Toolbox(C). A mental health battery consisting of the Extended Strengths and Weaknesses Assessment of Normal Behaviour (E-SWAN), Strengths and Difficulties Questionnaire (SDQ) and Emotion Regulation Skills Questionnaire (ERSQ) was also administered to provide proxy measures of the mental health. Cluster analyses revealed that the sample of neurodivergent adults was best represented by three data-driven clusters, none of which mapped coherently onto traditional diagnostic labels. These transdiagnostic groups were best characterised by a combination of strengths and weaknesses along two multivariate dimensions: 1) cognitive flexibility and processing speed, and 2) language, memory, emotional wellbeing and behavioural regulation. Overall, this study provides novel, data-driven evidence to support the emerging multivariate, dimensional structure of NDs, and highlights several component processes which contribute to the complexity associated with ND outcomes in adults. Such findings may be used to inform future assessment and/or support strategies for neurodivergent adults beyond those framed by strictly categorical approaches.