Internet-based treatment of social phobia: A randomized controlled trial comparing unguided with two types of guided self-help Thomas Berger a, * , Franz Caspar a , Robert Richardson a , Bernhard Kneubühler a , Daniel Sutter a , Gerhard Andersson b, c a Department of Clinical Psychology and Psychotherapy, University of Bern, Gesellschaftsstrasse 49, CH-3012 Bern, Switzerland b Behavioural Sciences and Learning, Swedish Institute for Disability Research, Linköping University, Linköping, Sweden c Department of Clinical Neuroscience, Psychiatry Section, Karolinska Institutet, Stockholm, Sweden article info Article history: Received 31 August 2010 Received in revised form 10 December 2010 Accepted 22 December 2010 Keywords: Internet treatment Social anxiety disorder Guided self-help Randomized controlled trial (RCT) abstract Internet-based self-help for social phobia with minimal therapist support via email have shown efficacy in several controlled trials by independent research teams. The role and necessity of therapist guidance is, however, still largely unclear. The present study compared the benefits of a 10-week web-based unguided self-help treatment for social phobia with the same intervention complemented with minimal, although weekly, therapist support via email. Further, a third treatment arm was included, in which the level of support was flexibly stepped up, from no support to email or telephone contact, on demand of the participants. Eighty-one individuals meeting diagnostic criteria for social phobia were randomly assigned to one of the three conditions. Primary outcome measures were self-report measures of symptoms of social phobia. Secondary outcome measures included symptoms of depression, interper- sonal problems, and general symptomatology. Measures were taken at baseline, post-treatment, and at 6-month follow-up. Data from a telephone-administered diagnostic interview conducted at post- treatment were also included. Results showed significant symptom reductions in all three treatment groups with large effect sizes for primary social phobia measures (Cohen’s d ¼ 1.47) and for secondary outcome measures (d ¼ 1.16). No substantial and significant between-groups effects were found on any of the measures (Cohen’s d ¼ 00e.36). Moreover, no difference between the three conditions was found regarding diagnosis-free status, clinically significant change, dropout rates, or adherence measures such as lessons or exercises completed. These findings indicate that Internet-delivered treatment for social phobia is a promising treatment option, whether no support is provided or with two different types of therapist guidance. Ó 2010 Elsevier Ltd. All rights reserved. Introduction Internet-based therapeutic interventions have developed rapidly over the last decade. A growing body of evidence suggests that this new treatment form can lead to significant and enduring improvements in a variety of mental disorders (Barak, Hen, Boniel- Nissim, & Shapira, 2008; Spek et al., 2007). Particularly for the treatment of anxiety disorders, independent replications have consistently shown promising results for social phobia (Andersson et al., 2006; Berger, Hohl, & Caspar, 2009a; Botella et al., 2010; Carlbring, Bohman, et al., 2006a; Carlbring, Furmark, et al., 2006b; 2007; Titov, Andrews, Schwencke, Drobny & Einstein, 2008c; Titov, Andrews & Schwencke, 2008b), panic disorder (Carlbring, Bohman, et al., 2006a; Carlbring, Ekselius, & Andersson, 2003; Carlbring, Furmark, et al., 2006b; Klein & Richards, 2001; Klein, Richards, & Austin, 2006), post-traumatic stress disorder (Hirai & Clum, 2005; Knaevelsrud & Maercker, 2007; Lange, van den Ven, Schrieken, & Emmelkamp, 2001; Lange et al., 2003), and generalized anxiety disorder (Robinson et al., 2010). In the majority of these studies, a guided self-help approach has been used, in which the presentation of a web-based self-help program is combined with minimal but regular therapist contact. For anxiety disorders, this treatment format has proven to be effi- cacious regardless of whether it is delivered via the Internet (i.e., with a web-based self-help program and additional therapist support via email) or with more traditional means of communi- cation (i.e., with a self-help book and additional phone calls from a therapist) which was recently confirmed in a meta-analysis (Cuijpers, Donker, van Straten, & Andersson, 2010). The Internet, however, is a medium of communication and information that * Corresponding author. Tel.: þ41 31 631 34 07; fax: þ41 31 631 41 55. E-mail address: thomas.berger@ptp.unibe.ch (T. Berger). Contents lists available at ScienceDirect Behaviour Research and Therapy journal homepage: www.elsevier.com/locate/brat 0005-7967/$ e see front matter Ó 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.brat.2010.12.007 Behaviour Research and Therapy 49 (2011) 158e169