To Örebro University

Background: Internet-delivered cognitive behavior therapy (ICBT) for major depression has been tested in several trials, but only with follow-ups up to 1.5 years.

Aim: The aim of this study was to evaluate the outcome of ICBT 3.5 years after treatment completion.

Methods: A total of 88 people with major depression were randomized to either guided self-help or e-mail therapy in the original trial. One-third was initially on a waiting-list. Treatment was provided for eight weeks and in this report long-term follow-up data were collected. Also included were data from post-treatment and six-month follow-up. A total of 58% (51/88) completed the 3.5-year follow-up. Analyses were performed using a random effects repeated measures piecewise growth model to estimate trajectory shape over time and account for missing data. Results Results showed continued lowered scores on the Beck Depression Inventory (BDI). No differences were found between the treatment conditions. A large proportion of participants (55%) had sought and received additional treatments in the follow-up period. A majority (56.9%) of participants had a BDI score lower than 10 at the 3.5-year follow-up.

Conclusions: People with mild to moderate major depression may benefit from ICBT 3.5-years after treatment completion.