Here is the design of a clinical trial:

Official Title: Immersive Virtual Reality Based Training for Motor Function Rehabilitation of Upper Limbs After Subacute Stroke：Study Protocol of a Randomized Clinical Trial

Included conditions:
- Immersion Virtual Reality Training ,Stroke, Upper Extremity, Randomized Controlled Trial

Study Armgroups:
- {'label': 'The intervention group', 'type': 'EXPERIMENTAL', 'description': 'The intervention group will participate in immersion virtual reality based rehabilitation training for 3 weeks.', 'interventionNames': ['Other: immersion virtual reality (VR)-based rehabilitation']}
- {'label': 'The control group', 'type': 'OTHER', 'description': 'The control group will receive for traditional rehabilitation training for 3 weeks.', 'interventionNames': ['Other: traditional rehabilitation training']}

Interventions:
- {'type': 'OTHER', 'name': 'immersion virtual reality (VR)-based rehabilitation', 'description': 'Intervention group received VR-based rehabilitation,including Virtual kitchen and so on.The patients took part in the exercise program for 30 minutes each day, five times per week, for 3 weeks. All subjects received physiotherapy, which accounts for an average of 30 minutes of physiotherapy per day on tolerance.', 'armGroupLabels': ['The intervention group']}
- {'type': 'OTHER', 'name': 'traditional rehabilitation training', 'description': 'The traditional rehabilitation training included occupational therapy and physical therapy, patients took part in the traditional rehabilitation training for 60 minutes each day, five times per week, for 3 weeks.', 'armGroupLabels': ['The control group']}

Primary Outcomes:
- {'measure': 'Change from Baseline Arm Movement Ability at 3 months', 'description': 'The Fugl-Meyer Assessment', 'timeFrame': 'Baseline and at 3 months'}

Please estimate the sample size based on the assumption: 
A two-tailed comparison with a type I error rate of 0.05 and 80% power. A conservative dropout rate of 25% is assumed.
Sample size considerations
        This randomized controlled trial is a two-group independent design examining the effects of immersive VR on rehabilitation of subjects with subacute stroke. We assumed a two-tailed comparison and set the type I error rate at 0.05 with 80% power. We plan to screen approximately 100 individuals with subacute stroke. After screening, 80 subjects will be recruited and randomized to the experimental group or the control group. As a conservative estimate (dropout rateâ=â25%), we presume that 60 subjects will complete the study. To reduce the dropout rate, we will employ two strategies to keep participants engaged: regular communication via phone or social media and clinician visits. After conducting a power analysis based on the aforementioned statistical parameters using the software GPower3.1.9.2 [39], the effect size is calculated as 0.74, which is between a medium (0.5) and large (0.8) effect size [40]. Moreover, there is evidence from a small sample (8 subjects) that VR-enhanced treadmill training for 5 sessions per week over 3âweeks induces significant cerebral reorganization [41]. Thus, 30 subjects for one group is sufficient to assess the effectiveness of immersive VR training in post-stroke rehabilitation in eliciting upper-limb motor recovery post-stroke compared to traditional rehabilitation training, and to investigate the underlying brain mechanisms of immersive VR-based rehabilitation using three MRI modalities.