Here is the design of a clinical trial:

Official Title: Functional Outcome Response to Engaging Virtual Reality in Pediatric Patients: a Randomized Clinical Trials

Included conditions:
- Pain, Postoperative
- Pain
- Anxiety Postoperative

Study Armgroups:
- {'label': 'VR-Biofeedback', 'type': 'OTHER', 'interventionNames': ['Other: VR-Biofeedback']}
- {'label': 'VR-Distraction', 'type': 'OTHER', 'interventionNames': ['Other: VR-Distraction']}
- {'label': '360 Video', 'type': 'OTHER', 'interventionNames': ['Other: 360 Video']}

Interventions:
- {'type': 'OTHER', 'name': 'VR-Biofeedback', 'description': 'Participants will be instructed to use the Mindful Aurora application', 'armGroupLabels': ['VR-Biofeedback']}
- {'type': 'OTHER', 'name': 'VR-Distraction', 'description': 'Participants will be instructed to use one of three applications', 'armGroupLabels': ['VR-Distraction']}
- {'type': 'OTHER', 'name': '360 Video', 'description': 'Participants will be instructed which video to view', 'armGroupLabels': ['360 Video']}

Primary Outcomes:
- {'measure': 'Effect of VR-biofeedback on pain', 'description': 'Pain scores will be collected. Pain will be rated using the numerical rating scale. Participant will rate their pain from 0 - 10. 0 meaning no pain and 10 being the worst pain imaginable.', 'timeFrame': 'Postoperatively 24 - 90 hours.'}
- {'measure': 'Effect of VR-distraction on pain', 'description': 'Pain scores will be collected. Pain will be rated using the numerical rating scale. Participant will rate their pain from 0 - 10. 0 meaning no pain and 10 being the worst pain imaginable.', 'timeFrame': 'Postoperatively 24 - 90 hours.'}
- {'measure': 'Effect of 360 video on pain', 'description': 'Pain scores will be collected. Pain will be rated using the numerical rating scale. Participant will rate their pain from 0 - 10. 0 meaning no pain and 10 being the worst pain imaginable.', 'timeFrame': 'Postoperatively 24 - 90 hours.'}

Please estimate the sample size based on the assumption: 
Significance level (alpha) is 0.025 to control for two comparisons. The power is 80%.
Sample size calculation
        Sample size calculation is based on preliminary data assessing the impact of VR-D to affect changes in pain intensity in children and adolescents following surgery (unpublished). Preliminary data showed that the average change in pain intensity across time was â1, with SD 1.2 and correlation between measurement pairs of 0.88. Assuming similar results in the passive control group, sample size of 30 per group will have 80% power to detect differences in mean changes of one between VR-GR and the two control groups. We expect a difference of â¥1 between VR-GR and VR-D to emerge with multiple sessions as proposed with this study. Significance (alpha) is 0.025 to control for two comparisons. We are recruiting 90 patients, 30 per group.