Discussion
phobia, anxiety
The results of this single-blind RCT demonstrated that a VR-CBT app using a rudimentary cardboard VR viewer and delivered in a natural setting without human contact was effective in reducing fear-of-flying symptoms at post-test and at both 3-month and 12-month follow-up. The effect sizes are similar to therapist-guided It has been argued that VR exposure lowers the threshold for exposure One of the main strengths of this trial was that the intervention took place in the participants' natural environment, thus increasing ecological validity. Furthermore, any influence of human contact on the findings was ruled out because participants did not receive any therapist guidance during treatment or when responding to assessments. Additional strengths were that the treatment had cross-platform compatibility (i.e. could be used on both iPhone and Android smartphones) and that the treatment was developed for common smartphones (up to approximately 5 years old), thereby increasing generalizability. Finally, this is the first study to demonstrate that the effects of fully automated VR-CBT in a real-life setting can be maintained long term.This study also had several limitations. First, the Simulator Sickness Questionnaire, which is commonly used to measure cyber sickness, could not be included because it overlaps with symptoms of anxiety and might therefore not be a valid measure of cyber sickness when used in studies of phobia treatment (Donker et al., 