Predicting the path to guided ICBT success across referral pathway for moderate depression and anxiety disorders

Depression and anxiety disorders are highly prevalent and burdensome conditions. Guided internet-delivered cognitive behavioral therapy (guided ICBT) is an effective treatment option, yet outcome prediction has shown inconsistent results. By analyzing patient-, treatment-, and system-related predictors within a single integrative framework, we aim to support a more nuanced understanding of what works for whom in which context. Naturalistic, open predictor-study in routine care comparing symptom reduction from pre-treatment (Pre) to post-treatment (Post), and from Pre to 6-month follow-up (FU), across general practitioner (GP) and self-referral pathways for depression and anxiety disorders. Patients self-reported symptoms Pre, Post, and FU. Symptom severity and change over time were assessed transdiagnostically applying a harmonized outcome score. Patient-related predictors were gender, age, education, employment status, duration of illness, and social support, while treatment-related predictors were treatment credibility and self-efficacy. The system-related predictor was referral pathways. In the total sample ( N = 460, GP = 305, Self-referred = 155), almost all patient-, treatment- and system-related predictors were associated with symptom reduction over time measured at Post and FU. Referral pathway statistically significant moderated the associations between most predictors and symptom reduction. Using a novel integrative approach, we identified unique adjusted associations between predictors across patient-, treatment-, and system-related predictors and symptom reduction in guided ICBT. Referral pathway moderated their relevance, underscoring the importance of contextual factors in shaping treatment response in routine care. • Referral pathway predicted and moderated symptom reduction in guided ICBT. • Self-referred patients improved more than GP-referred at Post and 6-month follow-up. • Predictive value of pre-treatment factors varied by referral pathway. • Treatment credibility and self-efficacy predicted short- and long-term outcomes. • Lower social support was associated with greater symptom reduction in both groups.