Here is the design of a clinical trial:

Official Title: Endoscopic Polypectomy Performed In Clinic for Chronic Rhinosinusitis With Polyps: The EPIC Randomised Controlled Trial

Included conditions:
- Sinusitis
- Nasal Polyps

Study Armgroups:
- {'label': 'Endoscopic polypectomy in clinic (EPIC)', 'type': 'EXPERIMENTAL', 'description': 'Patients assigned to this arm of the study will undergo the In Clinic Polypectomy Performed in Clinic', 'interventionNames': ['Procedure: Endoscopic polypectomy in clinic (EPIC)', 'Other: Local and topical anesthesia']}
- {'label': 'Endoscopic Sinus Surgery (ESS)', 'type': 'ACTIVE_COMPARATOR', 'description': 'Patients assigned to this arm will undergo endoscopic sinus surgery (ESS),', 'interventionNames': ['Procedure: Endoscopic Sinus Surgery (ESS)', 'Other: General Anesthesia']}

Interventions:
- {'type': 'PROCEDURE', 'name': 'Endoscopic polypectomy in clinic (EPIC)', 'description': 'The experimental intervention is endoscopic polypectomy performed in clinic (EPIC) where nasal polyps are removed using a microdebrider under local and topical anesthesia in the outpatient clinic.', 'armGroupLabels': ['Endoscopic polypectomy in clinic (EPIC)']}
- {'type': 'PROCEDURE', 'name': 'Endoscopic Sinus Surgery (ESS)', 'description': 'The control intervention is endoscopic sinus surgery (ESS), a minimally invasive procedure that is the current standard that involves polypectomy with a microdebrider as well as sinus ostia enlargement of the affected sinuses performed in the operating room under general anesthesia.', 'armGroupLabels': ['Endoscopic Sinus Surgery (ESS)']}
- {'type': 'OTHER', 'name': 'General Anesthesia', 'description': 'ESS will be performed under general anesthesia in the operating room', 'armGroupLabels': ['Endoscopic Sinus Surgery (ESS)']}
- {'type': 'OTHER', 'name': 'Local and topical anesthesia', 'description': 'EPIC will be performed under topical and local anesthesia in a clinic setting', 'armGroupLabels': ['Endoscopic polypectomy in clinic (EPIC)']}

Primary Outcomes:
- {'measure': 'Sinonasal Outcome Test-22 (SNOT-22)', 'timeFrame': '3 months'}

Please estimate the sample size based on the assumption: 
95% one-sided confidence limit on the difference in scores; 80% power; 10% dropouts and cross-overs.
Sample size
        Our primary outcome, the SNOT-22 score, is a validated and reliable tool for assessing symptoms of CRS with polyps.29 Considering the primary outcome of SNOT-22 score, and based on an analysis of covariance (ANCOVA) test of the group differences in SNOT-22 scores, we calculated the minimum necessary sample size with the following assumptions: equal effects of EPIC and ESS; a margin of non-inferiority of 8.9 points, which is equal to the minimally clinically important difference of the SNOT-22 score; an SD of 20 points on SNOT-22 score; a 95% one-sided confidence limit on the difference in scores; and 80% power. Using a non-inferiority test of the null hypothesis that EPIC is superior to ESS by more than the margin of non-inferiority (8.9 points on the SNOT-22 score), a total of about 63 people would be required for enrolment in each arm of the study. Accounting for 10% dropouts and cross-overs from each arm of the trial, using the method of Lachin,30 an adjusted study size of 140 patients will be required. We selected a non-inferiority margin of 8.9 as it has been demonstrated to be the minimally important difference for the SNOT-22, that is, a change of less than 8.9 points cannot be perceived by a patient to be a clinically important improvement.