Blended treatment for depression in routine practice
Authors:   , Kemmeren Lise Lotte 
Published: April 2023

The studies in this thesis were all conducted as part of the E-COMPARED project (“European comparative effectiveness research on internet-based depression treatment”; www.E-Compared.eu). E-COMPARED sought to determine how treatments using digital tools interwoven with traditional face-to-face therapy sessions could improve the scope and (cost-)effectiveness of depression care. Although the empirical basis for online interventions in (self-)guided formats is relatively sound, only a small number of patients are reached with online treatments in routine practice. So-called blended approaches integrating in-person sessions with a therapist with online sessions, seek to preserve the advantage of the face-to-face relation with patients to individualize treatment, combined with easily accessible and well-structured online material to reduce therapist time and increase patients’ self-management. Blended treatment is however a relatively new concept and the empirical evidence for clinically diagnosed major depression is still in its infancy. This thesis aimed to extend upon the existing literature, by exploring:
▪	the clinical effectiveness of bCBT for adults diagnosed with major depressive disorder (MDD) in routine specialized mental healthcare settings in the Netherlands, when compared to treatment-as-usual (TAU)
▪	the actual usage of bCBT in routine mental healthcare practice, across four European countries (the Netherlands, France, Poland and Germany)
▪	factors that have impact on the usage and outcome of bCBT, including treatment components and patient characteristics
▪	potential negative effects following bCBT and self-guided iCBT.

Summary of the main findings
Chapter 2 and 3 present the pragmatic RCT conducted in the Netherlands, as part of the E-COMPARED project, directly comparing bCBT to TAU. Results showed that bCBT is as effective as TAU in reducing depressive symptoms and improving quality of life. Patients following bCBT showed significant improvements on depressive symptoms, going from severe to mild symptom severity, along with large within-group effects at 6-months FU (d=1.18) that were maintained at 12-months FU (d=1.32). Additionally, no between-group differences were found on the number of reported negative effects, nor on intensity score of negative effects related to therapy as assessed with the ‘Inventory of Negative Effects of Psychotherapy’ (INEP). We concluded that applying bCBT in routine specialized mental healthcare seems worthwhile.
Chapter 4 and 5 examined the usage of the different components of bCBT by patients across four participating E-COMPARED sites working with the Moodbuster platform (the Netherlands, France, Germany and Poland) and investigated which components of bCBT and which patient characteristics contributed to a decrease in depressive symptoms. Results indicate that 90% of patients was compliant to the blended treatment approach, by integrating both a considerable and comparable amount of FTF and online activities. Furthermore, patients’ pre-treatment attitudes seem to influence usage and treatment outcomes of bCBT: patients with a preference for bCBT were more compliant with the blended format and having more positive expectancy of bCBT was associated with greater symptom improvements. Comorbidity however was associated with less compliance to a blended approach and less improvement in treatment outcome of bCBT.
Chapter 6 described the results of an individual participant data meta-analysis (IPDMA) of 13 RCTs (3876 participants) examining possible negative outcomes of self-guided iCBT compared to control conditions in adults with depressive symptoms, as well as potential moderating effects. Findings demonstrated that self-guided iCBT resulted in lower risk for clinically significant and any deterioration compared to controls (including regular care services) at the post-treatment assessment. None of the examined participant- and study-level variables was significantly associated with symptom deterioration rates.