Factorial Trial Investigating Outcome and Adherence Relevant Factors in an Online Self-help Intervention for Depression

A vast amount of studies show that online interventions are suitable to reduce symptoms of mental illness as for instance depression or anxiety. However, participants who use online interventions are more likely to drop out of treatment compared to face-to-face interventions. It is important to enhance adherence to online interventions so that participants engage longer in the programs. Also, as online interventions are useful to reduce the burden of mental illness, it is of interest to further improve outcomes of such interventions. Therefore, it will be investigated in this study whether or not four different factors have an impact in fostering adherence to and improving outcome of an internet-based self-help intervention based on problem-solving therapy. A multifactorial design will be used for this study to screen simultaneously whether or not i) a diagnostic telephone interview and, ii) an educational module based on motivational interviewing prior to the intervention and iii) guidance by the study team, and iv) automated e-mail reminders during the study are active factors in enhancing adherence to and outcome of online interventions.