The Hierarchical Taxonomy of Psychopathology in Adolescents: Support for a Neurodevelopmental Spectrum Without ADHD

Using the Hierarchical Taxonomy of Psychopathology (HiTOP) as our framework, the current study examines how 13 common psychological disorders can be grouped into different spectra in two groups of adolescents: a community sample (N = 951), and a clinic-referred sample (N = 173). Scores for the disorders were obtained using the parent version of the Child and Adolescent PsychProfiler. Taken together, the findings across the two samples for factor structure, reliability, and discriminant and concurrent validity indicate the most support for a three-factor CFA oblique model with primary factors for neurodevelopment disorders (that include Specific Learning Disorder, Autism Spectrum Disorder, Language Disorder, and Speech Sound Disorder), internalizing disorder problems (that include Generalized Anxiety Disorder, Persistent Depressive Disorder, Separation Anxiety Disorder, Obsessive–Compulsive Disorder, Posttraumatic Stress Disorder, Anorexia Nervosa, and Bulimia Nervosa), and externalizing disorder problems [(that include Attention Deficit/Hyperactivity Disorder (ADHD), and Oppositional Defiant Disorder/Conduct Disorder (ODD/CD)], with a covariance for the error variance for Anorexia Nervosa and Bulimia Nervosa. Additionally, the analysis for Sample 2 supports the concurrent validity of the factors in this model. A modification of this model, with ADHD cross-loading on the neurodevelopment disorders factor, did not produce an admissible solution. The findings indicate support for a neurodevelopmental spectrum in the HiTOP model, with ADHD and ODD/CD showing stronger statistical association with the externalizing factor than with the neurodevelopmental factor in the models tested. This finding pertains to dimensional structure and does not invalidate the neurodevelopmental classification of ADHD in DSM-5-TR.