Here is the design of a clinical trial:

Official Title: A Multi-center, Randomized Controlled Trial Comparing Early Versus Elective Colonoscopy in Outpatients With Acute Lower Gastrointestinal Bleeding

Included conditions:
- Acute Lower Gastrointestinal Bleeding

Study Armgroups:
- {'label': 'Early colonoscopy', 'type': 'EXPERIMENTAL', 'description': 'Performance of prepared colonoscopy within 24 h of arrival', 'interventionNames': ['Procedure: Early colonoscopy']}
- {'label': 'Elective colonoscopy', 'type': 'ACTIVE_COMPARATOR', 'description': 'Performance of prepared colonoscopy between 24 and 96 h after arrival', 'interventionNames': ['Procedure: Elective colonoscopy']}

Interventions:
- {'type': 'PROCEDURE', 'name': 'Early colonoscopy', 'description': 'Performance of prepared colonoscopy within 24 h of arrival', 'armGroupLabels': ['Early colonoscopy']}
- {'type': 'PROCEDURE', 'name': 'Elective colonoscopy', 'description': 'Performance of prepared colonoscopy between 24 and 96 h after arrival', 'armGroupLabels': ['Elective colonoscopy']}

Primary Outcomes:
- {'measure': 'Stigmata of Recent Hemorrhage (SRH) Identification Rate', 'description': 'Stigmata of Recent Hemorrhage (SRH) based on colonoscopic visualization of lesions, such as diverticulosis, tumor, ulcer, hemorrhoid, angioectasia, and polyps exhibiting active bleeding, a visible vessel, or an adherent clot.', 'timeFrame': '0-4 day'}

Please estimate the sample size based on the assumption: 
alpha level of 5% (two-sided), 80% statistical power, and correction for patient noncompliance/dropout
Sample size estimation
        Assuming that the SRH rate in the elective-colonoscopy patients is 9% and the SRH rate in the early-colonoscopy patients is 26% (or higher) [14], with an alpha level of 5% (two-sided), a sample size of 142 (2âÃâ71) patients will be required to ensure an 80% probability of obtaining a statistically-significant Ï2 test result (i.e., an 80% statistical power). Because the observed difference might be diminished by patient noncompliance and/or dropout, we will recruit 20 additional patients to correct for these effects, and thus will recruit a total of 162 patients for this trial.