Objective: Both Internet-delivered cognitive behavioural therapy (ICBT) and Internet-delivered psychodynamic psychotherapy (IPDT) have shown promise in the treatment of social anxiety disorder (SAD). However, little is known about client preferences and what predicts treatment outcome. The objective of the present pilot study was to examine preference for ICBT versus IPDT in the treatment of SAD and whether participants' preference strength and therapeutic alliance predicted treatment response. Further, we also investigated the effect of the two treatments, including 6-months follow-up.

Method: Thirty-six participants were instructed to choose between either IPDT or ICBT based on a brief description. Both treatments were 10 weeks long. Liebowitz Social Anxiety Scale – Self Report was used as the primary outcome measure.

Results: IPDT (N = 23; 63.9%) was preferred more often than ICBT (N = 13; 36.1%), but the difference did not reach statistical significance (p = .10). Preference strength did not predict the treatment effect but therapeutic alliance did. The observed within-group effects for the treatment period were d = 0.40 [−0.21, 0.99] for the IPDT group and d = 0.53 [−0.29, 1.31] for the ICBT group. An intention-to-treat (ITT) analysis revealed no significant difference between the two treatments on any outcome measure at either post-treatment or at six months follow-up.

Conclusion: The present pilot study did not find a difference in preference for IPDT or ICBT in the treatment of SAD and both treatments resulted in small to moderate improvements in symptoms of SAD. Preference strength might not predict treatment effect, but this needs to be tested in larger studies.