Here is the design of a clinical trial:

Official Title: Seroma Reduction and Drain Free Mastectomy

Included conditions:
- Breast Cancer
- Seroma
- Wound Complication

Study Armgroups:
- {'label': 'With drain', 'type': 'ACTIVE_COMPARATOR', 'description': 'Patients undergo mastectomy with flap fixation and low vacuum drainage.', 'interventionNames': ['Procedure: With drain']}
- {'label': 'No drain', 'type': 'EXPERIMENTAL', 'description': 'Patients undergo mastectomy with flap fixation and low vacuum drainage is omitted.', 'interventionNames': ['Procedure: No drain']}

Interventions:
- {'type': 'PROCEDURE', 'name': 'No drain', 'description': 'Mastectomy with flap fixation without low vacuum drainage', 'armGroupLabels': ['No drain']}
- {'type': 'PROCEDURE', 'name': 'With drain', 'description': 'Mastectomy with flap fixation with low vacuum drainage', 'armGroupLabels': ['With drain']}

Primary Outcomes:
- {'measure': 'Seroma aspiration of clinically significant seroma', 'description': 'Proportion of patients undergoing seroma aspiration of clinically significant seroma\n\nClinically significant seroma defined as:\n\n1. Wound healing is at risk due to seroma (wound break down, seroma leakage, necrosis)\n2. There is discomfort or pain caused by large amounts of seroma, characterised by tenseness of the skin.\n3. There is contaminated/ infected seroma and aspiration is necessary to treat infection. All patients that undergo seroma aspiration due to infection will also be treated with a one week course of Augmentin 625 mg 3 times daily.', 'timeFrame': 'During first six months post-operative'}

Please estimate the sample size based on the assumption: 
Significance level is not explicitly stated, power is 80%, and the dropout rate is 10%.
Sample size
        Based on previous studies conducted with a follow-up period of 1 year we estimate that about 10% of women in each group require seroma aspirations. If the rate of women requiring aspirations in the drain free group would be 10% larger than the overall aspiration rate of 10%, we would conclude that drain free mastectomy is inferior to standard mastectomy (i.e., the non-inferiority limit is 10%). To be able to have 80% power to reject the null-hypothesis that drain free mastectomy is inferior if in reality it is not, we need to include at least 112 patients per group. To account for a potential drop-out rate of 10% we will include 125 patients per group, or 250 in total. We expect that enrolment of these patients for the study will take 18âmonths.