Four-Year Follow-Up of High versus Low Intensity Summer Treatment for Adolescents with ADHD

Despite an emergence of psychosocial treatments for adolescent ADHD, their long-term effects are unknown.

We examine four-year outcomes of a randomized controlled trial (N = 218) comparing high-intensity (HI; 412 h, $4,373 per participant) versus low-intensity (LI; 24 h, $97 per participant) skills-based summer intervention delivered to adolescents with ADHD at two secondary school transitions (6th/9th grade). Quantitative and qualitative analyses evaluated group×time and group×grade×time effects on 4-year outcomes.

Relative to LI, a single dose of HI had modest but lasting effects on teen organization skills (d =.40) and ADHD symptoms (9th grade only: d =.27 to.31) at 4-year follow-up. There was no long-term incremental effect of HI (vs. LI) for parent-teen conflict, GPA, or parent use of contingency management. Treatment appeared most effective when delivered to older adolescents (i.e., 9th versus 6th grade), suggesting the long-term impact of ADHD treatment may increase with age. Qualitative data corroborated that the primary long-term benefit of HI (vs. LI) treatment was to organization skills; many of the remaining perceived benefits were to parent and teen psychological variables (i.e., increased self-esteem, self-awareness, parental optimism). HI offered no incremental benefit to long-term educational or clinical service utilization or costs.

Modest therapeutic benefits of adolescent ADHD treatment are maintained long term. However, HI treatment did not impact outcomes that could defray the intervention's high costs ($4,373) compared to LI treatment ($97).