Exploring Transdiagnostic Mechanisms of Youth Externalizing Psychopathology: A Longitudinal Person-Centered Approach.

The present study utilized an exploratory data analysis approach to consider how executive functioning (EF) relates to the developmental course of externalizing psychopathology using the Oregon ADHD-1000 dataset. Multinomial logistic regressions of EF domains (working memory, processing speed, set shifting, reaction time variability, response inhibition, and vigilance) in predicting symptomatic classes and longitudinal pathways from a recent latent transition analysis (Smith et al., in press) were conducted; predicted probability figures were interpreted. Findings suggest that hyperactivity/impulsivity (HI) was most related to EF impairment in many domains. Inattention contributed to set shifting and processing speed impairment specifically. HI and oppositionality were very aligned with one another in childhood and diverged in adolescence. Youth who were HI in childhood and inattentive in adolescence were distinct in EF impairment from youth who were inattentive across development. Findings reiterate the importance of exploratory, person-centered, longitudinal approaches for understanding heterogeneity, comorbidity, and developmental psychopathology.