Do sluggish cognitive tempo symptoms improve with school-based ADHD interventions? Outcomes and predictors of change

Sluggish cognitive tempo (SCT) is a construct that includes symptoms of slowness, excessive daydreaming, and drowsiness. SCT is often comorbid with attention-deficit/hyperactivity disorder (ADHD), and SCT symptoms are associated with significant academic impairment above the influence of ADHD. Despite the overlap between ADHD and SCT and associated impairments, no studies have evaluated how evidence-based psychosocial interventions for adolescents with ADHD impact symptoms of SCT.

This study examined whether SCT symptoms improved in a sample of 274 young adolescents with ADHD who were randomly assigned to an organizational skills intervention, homework completion intervention, or to a waitlist control. SCT intervention response was evaluated broadly in all participants and, specifically, for participants in the clinical range for SCT symptom severity at baseline. Change in ADHD symptoms of inattention, executive functioning, and motivation were examined as potential predictors of improvement in SCT.

The two intervention groups were collapsed together for analyses because there were no significant differences in change in SCT symptoms. Multilevel modeling results indicate that parent-reported SCT symptoms significantly decreased when comparing the intervention group to waitlist control (d = .410). For adolescents with parent-reported clinical levels of SCT, the decrease in symptoms was more pronounced (d = .517). Self-reported SCT symptoms produced null results, though effect size calculations showed small improvement for the full sample (d = .313) and for the high-SCT group (d = .384). Change in behavior regulation executive functioning (d = .247), metacognitive executive functioning (d = .346), and inattention (d = .230) predicted change in parent-reported SCT symptoms.

Although not specifically designed to decrease SCT symptoms, the ADHD interventions evaluated in this study resulted in significant improvements in parent-reported SCT with small to moderate effect sizes. Clinical implications and future directions are discussed, including development of interventions for adolescents with high levels of SCT.