Here is the design of a clinical trial:

Official Title: Uncut Roux-en-y Anastomosis Reduce Postoperative Complication and Improve Nutritional Status After Distal Gastrectomy

Included conditions:
- Nutrition Disorders
- Postoperative Complications

Study Armgroups:
- {'label': 'uncut Roux-en-Y anastomosis', 'type': 'EXPERIMENTAL', 'description': 'After distal gastrectomy, duodenal stump closure, side to side anastomosis was underwent on the remnant stomach and jejunum,which was 25cm from Treitz ligament. Then underwent side to side anastomosis between jejunum about 35cm distance from gastrojejunostomy and jejunum about 5cm from Triez ligament . close the intestinal cavity on the input less than 5cm distance from the loop gastrojejunostomy anastomosis by using uncut Closure devices', 'interventionNames': ['Procedure: Uncut Roux-en-Y anastomosis']}
- {'label': 'Billroth II anastomosis', 'type': 'SHAM_COMPARATOR', 'description': 'After distal gastrectomy, duodenal stump closure, the investigators first underwent remnant stomach and upper jejunum side anastomosis. Then choose the jejunum about 25cm from Treitz ligament, premenstrual colon using a disposable cutting closure (or tubular stapling) in the rear wall of the stomach and jejunum anastomosis, common opening was closed with the (barbed wire) hand-stitched. After that, steps were same with the group A.', 'interventionNames': ['Procedure: Billroth II anastomosis']}

Interventions:
- {'type': 'PROCEDURE', 'name': 'Uncut Roux-en-Y anastomosis', 'description': 'Uncut Closure devices would be used to close the intestinal cavity on the input less than 5cm distance from the loop gastrojejunostomy anastomosis.', 'armGroupLabels': ['uncut Roux-en-Y anastomosis']}
- {'type': 'PROCEDURE', 'name': 'Billroth II anastomosis', 'description': 'Typical Billroth II anastomosis would be made after the Distal gastrectomy.', 'armGroupLabels': ['Billroth II anastomosis']}

Primary Outcomes:
- {'measure': 'Number of participants with treatment-related gastrointestinal and gastroesophageal reflux as assessed by The Los Angeles and Savary-Miller systems for grading esophagitis', 'timeFrame': '0-5 years'}

Please estimate the sample size based on the assumption: 
The sample size estimation used a difference test with 80% power, a 5% significance level, and accounted for a 15% drop-out rate. The allocation ratio is 1:1.
Sample size
        Our study is designed as a superiority trial whose primary outcome is postoperative reflux gastritis or not. Current experience suggests the predicted rate of postoperative reflux gastritis will be 8% for the uncut Roux-en-Y anastomosis group and 12% for the control group of Billroth II anastomosis. The difference test was used to estimate the sample size with 80% test power and a 5% significance level. Accounting for a 15% drop-out rate and the 1:1 allocation ratio, the total number of patients required per group is 416 (832 in total), which was calculated using the software PASS version 11.0. Considering a completion rate of 75% for each coordinating center, 1040 envelopes were designed for random allocation. The number of cases will be increased if necessary according to the results of the interim analysis.