Adaptive stepped care in preschool-age children with ADHD symptoms: a multicentre study including two consecutive randomised controlled trials (ESCApreschool).

Parent training and assisted self-help have proven effective in preschool-age children with attention-deficit/hyperactivity disorder (ADHD). This study analysed a stepped-care approach combining these interventions. Participants were children (3-6 years) with either ADHD or oppositional defiant disorder (ODD) plus substantial ADHD symptoms. Study Step 1 (three months) comprised a randomised, waitlist-controlled trial on the efficacy of parent-directed telephone-assisted self-help (TASH). Based on the response to TASH, in Step 2 (six months), participants either received TASH booster sessions (full responders) or participated in another randomized controlled trial (partial/non-responders) comparing parent management and preschool teacher training (PMPTT) with treatment as usual (TAU). The primary outcome was change in blinded-clinician-rated ADHD and ODD symptoms. The primary analyses were by intention-to-treat. 189 children (79.9% boys, mean age = 5.1 years) were randomised. A univariate analysis of covariance did not yield a significant difference in the primary outcome for Step 1 (nTASH=58, nWaitlist=54; mean difference  -0.13 ± 0.07, 95%-CI -0.26-0.01; p = 0.06; d= -0.30). Following TASH, 67 children (40.9%) showed a full response and 97 a partial/non-response. In Step 2, PMPTT was superior to TAU (nPMPTT=23, nTAU=37; mean difference -0.23 ± 0.11, 95%-CI -0.44-[-0.01]; p = 0.040; d=-0.52, 95%-CI -1.02-[-0.03]). Furthermore, TASH showed effects on parent-rated externalizing symptoms, negative parenting, and parental self-efficacy, and PMPTT on semi-blinded-clinician- and parent-rated impairment. Stepwise adaptive treatment may be beneficial for preschoolers with ADHD. Initial TASH is associated with full responses in a subgroup. Consecutive PMPTT should be offered to children with residual symptoms. (German Clinical Trials Register; DRKS00008971; registered on 01 October 2015).