Internet-based treatment of social phobia: a randomized controlled trial comparing unguided with two types of guided self-help.

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, interpersonal 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=1.47) and for secondary outcome measures (d=1.16). No substantial and significant between-groups effects were found on any of the measures (Cohen's d=00-.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.