Here is the design of a clinical trial:

Official Title: Managing Non-acute Subdural Hematoma Using Liquid Materials：a Chinese Randomized Trial of MMA Treatment

Included conditions:
- Subdural Hematoma, Non-acute

Study Armgroups:
- {'label': 'Embolization', 'type': 'EXPERIMENTAL', 'description': 'Middle meningeal artery(MMA) embolization', 'interventionNames': ['Device: Onyx', 'Procedure: Burr-hole', 'Other: Medical Management']}
- {'label': 'No embolization', 'type': 'ACTIVE_COMPARATOR', 'description': 'Traditional treatment group', 'interventionNames': ['Procedure: Burr-hole', 'Other: Medical Management']}

Interventions:
- {'type': 'DEVICE', 'name': 'Onyx', 'description': 'Embolization of the Middle Meningeal Artery using the liquid embolic material', 'armGroupLabels': ['Embolization']}
- {'type': 'PROCEDURE', 'name': 'Burr-hole', 'description': 'Burr-hole drainage of subdural hematoma', 'armGroupLabels': ['Embolization', 'No embolization']}
- {'type': 'OTHER', 'name': 'Medical Management', 'description': 'best medical management', 'armGroupLabels': ['Embolization', 'No embolization']}

Primary Outcomes:
- {'measure': 'Incidence of symptomatic SDH recurrence/ progression within 90 days post-procedure', 'description': 'SDH recurrence (\\>10 mm max. thickness) or receiving re-operation in patients who underwent surgery/ symptomatic SDH progression (\\>3 mm increase in max thickness or receiving surgical rescue in patients who did not undergo sugery) at 90 days\n\n"Symptomatic" is hereby defined as one or more of the following features which are attributed to the progression/recurrence: headache, short-term cognitive decline, speech difficulty or aphasia, gait impairment, focal weakness, sensory deficits, seizures', 'timeFrame': '90 days'}

Please estimate the sample size based on the assumption: 
The trial is powered to assess superiority with a power of 90%, a two-sided alpha of 0.05, and an 8% drop-out rate.
Sample size {14}
        Our estimates are based on the hematoma recurrence or progression rate of conventional treatment from the literature. The hematoma recurrence or progression rate of conventional treatment ranged from 14 to 27.5% [14â18], and the hematoma progression rate of atorvastatin treatment is 11.2% as reported [9], so we assume the event rate of the control group is 12%. The hematoma recurrence of MMA embolization ranged from 1.4 to 8.9% as reported [14â18], and a systematic review reported that the recurrence rate for patients treated with MMA embolization for primary cSDH was 4.1% [19], so we assume the event rate of the intervention group is 5%. The trial is powered to assess superiority. When assuming the event rate of 5% in intervention group and 12% event rate in the control group, with a power of 90% and two-sided alpha of 0.05, allowing for 8% drop-outs, the estimated sample size is 722 patients in total.