Efficacy of a Stepped-Care Approach for Adolescents and Adults with Attention-Deficit/Hyperactivity Disorder: An Adaptive Intervention Study Including Randomized Controlled Trials (ESCAlate)

INTRODUCTION: This study evaluated the effectiveness of a stepped-care approach - a staged model that escalates from lower- to higher-intensity treatments according to clinical response - for the treatment of adolescents and adults with ADHD, taking into account symptom severity and prior treatment response. METHODS: In a multicenter study, adolescents and adults with ADHD (16-45 years) participated in a two-step treatment program including randomized controlled trials (RCTs). In step 1, patients were (block-)randomized to 3 months of psychoeducation (PE), telephone-assisted self-help (TASH), or waiting control (WC). In step 2 based on step 1 response (full, partial, none), patients either received counseling or were randomized to counseling with/without neurofeedback (NF) or pharmacological treatment (with/without NF) for 6 months. The primary outcome was change in clinician-rated ADHD symptoms, analyzed using linear (mixed-)effects models for repeated measures to account for correlations within participants over time. RESULTS: Between January 2015, and September 2020, N = 299 (mean age = 28 years, 55.2% male) patients were randomized in step 1. The primary outcome showed no significant between-group differences (PE vs. TASH: d = -0.12, 95% CI: -3.18, 1.19, p = 0.64; PE vs. control: d = -0.26, 95% CI: -4.25, 0.05, p = 0.13; TASH vs. control: d = -0.14, 95% CI: -3.24, 1.04, p = 0.57). However, significant within-group effects emerged (PE: d = -0.60; TASH: d = -0.48; WC: d = -0.34; p < 0.001). Step 2 also showed no between-group differences but significant within-group effects (MPH: d = -0.59; MPH+NF: d = -0.76; counseling: d = -0.57/-1.35, p = 0.01/p < 0.001). Mixed models revealed symptom reduction in all step 1 responders and step 1 non-responders in step 2. CONCLUSIONS: The lack of step 1 RCT differences questions the specific effects of PE/TASH. Similar patterns emerged in step 2, but intensified treatment for step 1 non-responders improved outcomes in MPH groups. Step 1 response influenced later treatment success. Some stepped-care combinations did not further reduce symptoms, but no rebound effects occurred. The main limitations of this study are the two-step design complexity, limited information on certain (additional) psychosocial components, and the need to make assumptions about missing data. Nevertheless, findings support the feasibility and partial effectiveness of a stepped-care approach.