Therapist-guided Internet-delivered versus Face-to-face CBT for Adults with ADHD: Differential Long-Term Maintenance and Exploratory Correlational Pathways.

OBJECTIVE: Therapist-guided Internet-delivered Cognitive Behavioral Therapy (iCBT) offers a promising alternative to face-to-face CBT (FTF-CBT) for adults with attention-deficit/hyperactivity disorder (ADHD), but evidence on its comparative efficacy and long-term maintenance mechanisms is limited. This study aimed to analyze the efficacy of group-format therapist-guided iCBT and FTF-CBT in medicated ADHD adults immediately post-treatment and at 1-year follow-up; and explored potential maintenance correlational pathways. METHODS: Secondary analysis of data from two randomized controlled trials (n = 184) comprised participants into three groups: group-format therapist-guided iCBT (n = 43), group-format FTF-CBT (n = 49), and treatment as usual (TAU; n = 92). Outcomes included ADHD core symptoms, anxiety symptoms, dysfunctional attitudes, and psychological quality of life (QoL). Linear Mixed Models were utilized to assess treatment efficacy both at post-treatment and 1-year follow-up, and exploratory structural equation path modeling was used to investigate synchronous correlational patterns of long-term symptom changes between the two active intervention groups. RESULTS: At post-treatment, both group-format interventions demonstrated significant improvements over the TAU group in reducing ADHD core symptoms, alleviating anxiety, and enhancing psychological QoL (|d| = 0.230-0.828). At 1-year follow-up, FTF-CBT maintained benefits for all outcomes and was superior to iCBT across all four domains, while iCBT only retained significant advantages over TAU on ADHD core symptoms (d = -0.483) and psychological QoL (d = 0.217). The exploratory structural equation path model identified three significant correlational patterns: changes in dysfunctional attitudes were directly associated with psychological QoL changes (β = .899), indirectly via anxiety changes (β = .861), and through sequential changes in anxiety and ADHD symptoms (β = .146). CONCLUSION: While both group-format therapist-guided iCBT and FTF-CBT were effective at post-treatment, only FTF-CBT maintained benefits across all outcomes at 1-year follow-up and showed larger effect sizes than iCBT in exploratory comparisons. Exploratory path analyses identified the role of changes in dysfunctional attitudes in synchronous long-term symptom covariation linked to sustained psychological QoL. These findings offer valuable insights into strategies for enhancing the real-world impact of therapist-guided iCBT, highlighting areas for future research and clinical practice.Trial RegistrationChiCTR1900021705, ChiCTR2100044201 (Chinese Clinical Trial Registry, www.chictr.org.cn).