Here is the design of a clinical trial:

Official Title: SoREAL- a Randomized Clinical Trial

Included conditions:
- Social Anxiety Disorder
- Agoraphobia

Study Armgroups:
- {'label': 'CBT in virtuo', 'type': 'EXPERIMENTAL', 'description': 'Receives CBT in group format with Virtual Reality Exposure Therapy', 'interventionNames': ['Behavioral: CBT with virtual reality exposure therapy']}
- {'label': 'CBT in vivo', 'type': 'ACTIVE_COMPARATOR', 'description': 'Active comparator, receives CBT in group format. Treatment as usual.', 'interventionNames': ['Behavioral: CBT in vivo']}

Interventions:
- {'type': 'BEHAVIORAL', 'name': 'CBT with virtual reality exposure therapy', 'description': 'The patients receiving the in virtuo exposure will be immersed using an Oculus Go head-mounted display, enabling viewing of 360° spherically camera recorded VR environments. The VR scenarios will thus be high-resolution 360° stereoscopic films, that are played around the viewer. For ease of use, the individual videos will be administered from an app that has been designed to be as intuitive to operate as possible. The patient will only have to put on the headset, adjust the focus and choose the desired environment by looking at it in the app. 360° video was chosen because it gives the most photorealistic visuals, while also being the cheapest to produce. The downside is that it does not allow direct user-interaction (e.g. the viewer cannot affect the environment in any way). To circumvent this, there are multiple junctions throughout the films where the actors will talk directly and unsolicited to the viewer while also allowing time for the viewer to respond.', 'armGroupLabels': ['CBT in virtuo']}
- {'type': 'BEHAVIORAL', 'name': 'CBT in vivo', 'description': 'The therapeutic intervention is manual-based cognitive-behavioral CBT group therapy adapted from the approach of Turk, Heimberg \\& Magee and Graske \\& Barlow with worksheets from Arendt \\& Rosenberg and inspiration from Bouchard et al. The treatment will consist of 14 weekly two-hour group sessions following the manual to ensure equal and uniform treatment for every patient throughout the study. Concurrent psychopharmacological treatment is allowed in both intervention arms.', 'armGroupLabels': ['CBT in vivo']}

Primary Outcomes:
- {'measure': 'Change in symptom severity of primary diagnosis', 'description': "Total scores on the Liebowitz Social Anxiety Scale (LSAS) for patients with social anxiety disorder and the Mobility Inventory for Agoraphobia (MIA) for patients with Agoraphobia measured pre-treatment, post-treatment and at one-year follow-up converted to the 'Percentage of Maximum Possible Score' (POMP) and averaged within treatment arms. POMP calculations can bring differently measured items to the same metric and do not change the multivariate distribution and covariance matrix of the transformed variables.\n\nRanges from 0 to 100. Higher is worse.", 'timeFrame': 'Between 30 to 1 day(s) before treatment, between 0 and 14 days after treatment ends and between 365 to 395 days after first assesment.'}

Please estimate the sample size based on the assumption: 
Alpha=0.05, 80% power, and an expected standard deviation (SD) of 21.
Outcomes and sample size calculation
          We originally designed the trial around inclusion of only patients with social anxiety disorder, basing the sample size calculation on the following parameters on the LSAS: with alpha=0.05, 80% power, and an expected SD of 21, 302 patients would be required to detect the minimal relevant difference of 6.8 on the LSAS total score between the groups.
          On deciding to expand the diagnostic criteria for inclusion to also include patients with agoraphobia, it was necessary to change our primary outcome measure. For patients with agoraphobia, we primarily rate symptoms using MIA. To include both patients with social anxiety disorder and patients with agoraphobia, we thus decided to recalculate scores on these two scales to POMP as described below. Since the sample size calculation for LSAS was based on a Cohenâs d=0.33, we also set the minimum clinically relevant difference on MIA, and by extension on the POMP, to d=0.33. Consequently, the required sample size remained unaffected by this change of primary outcome measures and is thus still 302 patients. See figure 3 for power calculations on secondary outcomes.
          
            Figure 3
            
              Power calculation for secondary outcomes in the SoREAL trial. LSAS, Liebowitz Social Anxiety Scale; MIA, Mobility Inventory for Agoraphobia; VR, virtual reality.