Validity of the sluggish cognitive tempo symptom dimension in children: Sluggish cognitive tempo and ADHD-inattention as distinct symptom dimensions

Abstract

This study examined the validity of the sluggish cognitive tempo (SCT) symptom dimension in children. Ten symptom domains were used to define SCT (i.e.; (1) daydreams; (2) attention fluctuates; (3) absent-minded; (4) loses train of thought; (5) easily confused; (6) seems drowsy; (7) thinking is slow; (8) slow-moving; (9) low initiative; and (10) easily bored, needs stimulation). Teacher ratings of 366 children (ages 5 to 13 with 56 % girls) along with parent ratings of 703 children (ages 5 to 13 with 55 % girls) indicated that SCT symptom domains one to eight showed convergent validity (i.e.; substantial loadings on the SCT factor) and discriminant validity with the ADHD-IN dimension (i.e.; higher loadings on the SCT factor than the ADHD-IN factor). Higher scores on this eight-symptom measure of SCT predicted lower levels of academic and social competence even after controlling for ADHD-IN and ADHD-HI. In addition, higher SCT scores still predicted higher anxiety/depression scores after controlling for ADHD-IN and ADHD-HI. Higher SCT scores also predicted lower ADHD-HI scores after controlling for ADHD-IN and anxiety/depression while higher ADHD-IN and anxiety/depression scores predicted higher ADHD-HI scores after controlling for SCT and anxiety/depression or ADHD-IN. SCT also showed a unique negative relationship with ODD while ADHD-IN and anxiety/depression showed unique positive relationships with ODD. This new measure of the SCT dimension was meaningfully independent from the ADHD-IN and anxiety/depression dimensions and suggests that such an SCT dimension may signify a distinct presentation of ADHD or a different (if highly comorbid) disorder altogether. © 2013 Springer Science+Business Media New York.