This study compared Panic Online (PO), an internet-based CBT intervention, to best-practice face-to-face CBT for people with panic disorder with or without agoraphobia. Eighty-six people with a primary diagnosis of panic disorder were recruited from Victoria, Australia. Participants were randomly assigned to either PO (n=46) or best practice face-to-face CBT (n=40). Effects of the internet-based CBT program were found to be comparable to those of face-to-face CBT. Both interventions produced significant reductions in panic disorder and agoraphobia clinician severity ratings, self reported panic disorder severity and panic attack frequency, measures of depression, anxiety, stress and panic related cognitions, and displayed improvements in quality of life. Participants rated both treatment conditions as equally credible and satisfying. Participants in the face-to-face CBT treatment group cited higher enjoyment with communicating with their therapist. Consistent with this, therapists' ratings for compliance to treatment and understanding of the CBT material was higher in the face-to-face CBT treatment group. PO required significantly less therapist time than the face-to-face CBT condition.
rInternet-based interventions with therapist support have proven effective for treating a range of mental health conditions. This study examined whether frequency of therapist contact affected treatment outcomes. Fifty-seven people with panic disorder (including 32 with agoraphobia) were randomly allocated to an 8-week Internet-based cognitive behavioural treatment intervention (Panic Online) with either frequent (three e-mails per week) or infrequent (one e-mail per week) support from a psychologist. Posttreatment, intention-to-treat analyses revealed that both treatments were effective at improving panic disorder and agoraphobia severity ratings, panic-related cognitions, negative affect, and psychological and physical quality of life domains, with no differences between conditions. High end-state functioning was achieved by 28.6% of the frequent and infrequent participants, respectively. Therapist alliance, treatment credibility, and satisfaction also did not differ between groups, despite significantly greater therapist time invested in the frequent contact condition. The results provide evidence that the effectiveness of Internet-based mental health interventions may be independent of the frequency of therapist support and may, therefore, be more cost-effective than previously reported.