Long-term outcome of Internet-delivered cognitive-behavioural therapy for social phobia: a 30-month follow-up.

Internet-delivered guided cognitive behaviour therapy for social anxiety disorder has been found to generate promising short-term results, up to one year posttreatment. No study has however documented longer follow-up periods. In this 30-month follow-up we contacted 57 participants from the original study of which 77.2% (44/57) responded to the Internet-administered outcome measures and 66.7% (38/57) completed a telephone interview. Results showed large pretreatment to follow-up within-group effect sizes for the primary outcome measures (Cohen's d 1.10-1.71), and a majority (68.4%; 26/38) reported improvements in the interview. The findings suggest that the long-term effects seen in previous live treatment CBT trials can occur in Internet-delivered treatment as well.