Abstract
The Tower of London, Drexel Version, Second Edition (TOL-DX) is purported to measure multiple aspects of executive functions, although it also possesses inherent non-executive demands. Such complexity makes it useful in detecting impairment but difficult in interpreting the neurocognitive cause of impairment, particularly in children. This study investigated the developmental, neurocognitive, and symptom correlates of the TOL-DX in children and adolescents with neuropsychiatric disorders. Two-hundred and thirty-three children and adolescents (7-21 years old) completed the TOL-DX during a neuropsychological evaluation as part of clinical care within a children's psychiatric hospital. Pearson correlation, regression models, and receiver operating characteristic curve (ROC) analyses examined the association among variables. Visuospatial and executive functions (EF) were most consistently related to total moves, execution time, and violations. TOL-DX variables were associated with attention in younger participants and EF in older participants. No TOL-DX scores were related to parent-reported symptoms. The TOL-DX possesses inherent visuospatial and attention/executive demands in children and adolescents which are difficult to differentiate, differ by age group, and not associated to clinical symptoms. Taken together, the TOL-DX is complex to interpret, but psychometrically sound and sensitive to neurocognitive impairment in children and adolescents with transdiagnostic neuropsychiatric disorders.