Here is the design of a clinical trial:

Official Title: Vitrectomy, Subretinal Tissue Plasminogen Activator and Intravitreal Gas for Submacular Haemorrhage Secondary to Exudative Age-Related Macular Degeneration (TIGER): a Phase 3, Pan-European, Two-group, Observer-masked, Superiority, Randomised Controlled Surgical Trial.

Included conditions:
- Eye Diseases
- Macular Degeneration, Wet
- Sub-Macular Hemorrhage

Study Armgroups:
- {'label': 'Arm A - Surgery with aflibercept', 'type': 'EXPERIMENTAL', 'description': 'Surgery with aflibercept at the end of surgery, with post-operative review day 1 and week 1 (day 7)', 'interventionNames': ['Procedure: Pars plana vitrectomy', 'Drug: Intravitreal 2 mg aflibercept (Eylea, Bayer) will be injected at baseline then monthly for two further doses, then 2-monthly until month 12', 'Drug: subretinal injection of recombinant TPA (Alteplase) up to a maximum of 25 micrograms in 0.2 mls', 'Drug: Intravitreal 20% sulfahexafluoride (SF6) gas tamponade']}
- {'label': 'Arm B - Aflibercept monotherapy', 'type': 'ACTIVE_COMPARATOR', 'description': 'Aflibercept monotherapy commencing at baseline.', 'interventionNames': ['Drug: Intravitreal 2 mg aflibercept (Eylea, Bayer) will be injected at baseline then monthly for two further doses, then 2-monthly until month 12']}

Interventions:
- {'type': 'PROCEDURE', 'name': 'Pars plana vitrectomy', 'description': 'Pars plana vitrectomy', 'armGroupLabels': ['Arm A - Surgery with aflibercept']}
- {'type': 'DRUG', 'name': 'Intravitreal 2 mg aflibercept (Eylea, Bayer) will be injected at baseline then monthly for two further doses, then 2-monthly until month 12', 'description': 'Intravitreal 2 mg aflibercept (Eylea, Bayer) will be injected at baseline then monthly for two further doses, then 2-monthly until month 12.', 'armGroupLabels': ['Arm A - Surgery with aflibercept', 'Arm B - Aflibercept monotherapy'], 'otherNames': ['Aflibercept (Eylea, Bayer)']}
- {'type': 'DRUG', 'name': 'subretinal injection of recombinant TPA (Alteplase) up to a maximum of 25 micrograms in 0.2 mls', 'description': 'Subretinal injection of recombinant TPA (Alteplase, Actilyse, Boehringer Ingelheim) up to a maximum of 25 micrograms in 0.2 mls.', 'armGroupLabels': ['Arm A - Surgery with aflibercept'], 'otherNames': ['Actilyse (Boehringer Ingelheim)']}
- {'type': 'DRUG', 'name': 'Intravitreal 20% sulfahexafluoride (SF6) gas tamponade', 'description': 'Intravitreal 20% sulfahexafluoride (SF6) gas tamponade.', 'armGroupLabels': ['Arm A - Surgery with aflibercept']}

Primary Outcomes:
- {'measure': 'assessment of Early Treat of Diabetic Retinopathy Study (ETDRS) letters of best-corrected visual acuity (BCVA) in the study eye.', 'description': 'The primary outcome is the proportion of participants with a BCVA gain ≥10 ETDRS letters in the study eye at the 12 month visit.', 'timeFrame': '12 months'}

Please estimate the sample size based on the assumption: 
A two-group χ2 test with a 5% two-sided significance level and 90.62% power. An attrition rate of approximately 12% is assumed.
Sample size {14}
        To calculate our sample size, we undertook a bracketing exercise with our patient focus group as detailed below in the Public and Patient Involvement section. We asked them what improvement in âtreatment successâ, defined as meaningful gain in vision, they would require to undergo eye surgery, with the attendant downsides such as discomfort, head positioning, complications, recovery and possible cataract surgery, and assuming a 1 in 4 chance of success with anti-VEGF injections alone [7]. We defined treatment success as a 10Â letter gain in the ETDRS letter score (for justification see the section âPrimary efficacy outcomeâ).
        The findings ranged from one patient who would not want surgery âat my ageâ, regardless of outcome, to another who would have surgery even if it improved his success from only 25 to 26%. The most common response was that patients wanted at least a 50% chance of success to consider vitrectomy.
        What also emerged in this elderly patient focus group was a consensus that they wanted the doctor to make the best decision on their behalf. Paradoxically then, our patient focus group exercise led us to ask 10 ophthalmologists, from junior to senior, across a range of subspecialities, what they would do, âif it was their eyeâ. We asked them to assume they were older adults with â25% success with anti-VEGF therapy. The median âsuccess rateâ needed to consider surgery differed if it was their potentially better or worse seeing eye (47.5% vs 55% respectively), but overall the average, median, and mode were 49%, 50% and 50% respectively. Thus, we used 50% as the minimum success rate needed to justify surgery.
        Our synthesis of the literature [7] found that 27% of patients receiving anti-VEGF monotherapy for AMD-related SMH gained 2 Snellen lines (â10 letters).
        A two-group Ï2 test with a 5% two-sided significance level has 90.62% power to detect a difference between a Group 1 proportion, Ï1, of 0.27 and a Group 2 proportion, Ï2 of 0.5 (odds ratio 2.704) when the sample size in each group is 94 (NQuery Advanced software v 8.2.1). With â12% attrition, the sample size inflates to 210 participants.