Here is the design of a clinical trial:

Official Title: Acupuncture for Irritable Bowel Syndrome Patients: A Single-blinded Randomized Sham-controlled Clinical Trial

Included conditions:
- Irritable Bowel Syndrome

Study Armgroups:
- {'label': 'Acupuncture group', 'type': 'EXPERIMENTAL', 'description': 'Electro-acupuncture will be conducted for 2 sessions per week over 6 consecutive weeks. Disposable acupuncture needles (0.30 mm in diameter and 25-40 mm in length) are inserted at a depth of 10-30 mm obliquely into scalp acupuncture points (Baihui, Toulinqi) or straightly into body acupuncture points (Taichong, Zhangmen, Sanyinjiao, Zhongwan, Guanyuan, Tianshu, Zusanli). Electroacupuncture will be applied to the abdominal points at fast and dispersed waves through electric needle stimulator (ES-160 6-Channel Programmable Electro-acupuncture) for 30 min. The intensity is adjusted to a level at which patients feel comfortable.', 'interventionNames': ['Device: Acupuncture']}
- {'label': 'sham-acupuncture group', 'type': 'PLACEBO_COMPARATOR', 'description': 'Sham-acupuncture will be conducted for 2 sessions per week over 6 consecutive weeks. Disposable acupuncture needles (0.30 mm in diameter and 25-40 mm in length) are inserted at the same way as in the acupuncture group but on sham-acupuncture points (Sham-Baihui, Sham-Toulinqi, Sham-Taichong, Sham-Zhangmen, Sham-Sanyinjiao, Sham-Zhongwan, Sham-Guanyuan, Sham-Tianshu, Sham-Zusanli). The sham points are non-acupuncture points nor located on meridians', 'interventionNames': ['Device: Sham-acupuncture']}

Interventions:
- {'type': 'DEVICE', 'name': 'Acupuncture', 'description': 'Disposable acupuncture needles (0.30 mm in diameter and 25-40 mm in length) are inserted at a depth of 10-30 mm obliquely into scalp acupuncture points (Baihui, Toulinqi) or straightly into body acupuncture points (Taichong, Zhangmen, Sanyinjiao, Zhongwan, Guanyuan, Tianshu, Zusanli). Electroacupuncture will be applied to the abdominal points at fast and dispersed waves through electric needle stimulator (ES-160 6-Channel Programmable Electro-acupuncture) for 30 min. The intensity is adjusted to a level at which patients feel comfortable.', 'armGroupLabels': ['Acupuncture group']}
- {'type': 'DEVICE', 'name': 'Sham-acupuncture', 'description': 'Disposable acupuncture needles (0.30 mm in diameter and 25-40 mm in length) are inserted at the same way as in the acupuncture group but on sham-acupuncture points (Sham-Baihui, Sham-Toulinqi, Sham-Taichong, Sham-Zhangmen, Sham-Sanyinjiao, Sham-Zhongwan, Sham-Guanyuan, Sham-Tianshu, Sham-Zusanli). The sham points are non-acupuncture points nor located on meridians', 'armGroupLabels': ['sham-acupuncture group']}

Primary Outcomes:
- {'measure': 'Change on IBS-symptom severity scale', 'description': 'Value from 0-500. The higher the score, the more severe the symptoms. When there is lowering of the sore between baseline and treatments, it indicates clinical improvement.', 'timeFrame': '0,8,14 weeks'}
- {'measure': 'Change on Hamilton Depression Rating Scale (HAMD-17)', 'description': 'Value from 0-57. Scoring 8-16: mild depression, 17-23: moderate depression, over 24: severe depression. When there is lowering of the sore between baseline and treatments, it indicates improvement on depressive symptoms.', 'timeFrame': '0,8,14 weeks'}
- {'measure': 'Change on Clinical Global Impression-severity (CGI-S)', 'description': 'Rating from 1-7, the higher rate indicates more severe of the mental problem. The subject is rated by researcher from his clinical experience. When there is lowering of the rating between baseline and treatments, it indicates improvement.', 'timeFrame': '0,8,14 weeks'}
- {'measure': 'Change on Self-Rating Depression Scale (SDS)', 'description': 'Value from 20-80. Scoring 50-69: depression, over 70: severe depression. When there is lowering of the sore between baseline and treatments, it indicates improvement.', 'timeFrame': '0,8,14 weeks'}
- {'measure': 'Change on IBS Quality of Life (IBS-QoL)', 'description': 'Value from 35-170. The higher the score, the lower the quality of life. When there is lowering of the sore between baseline and treatments, it indicates improvement.', 'timeFrame': '0,8,14 weeks'}

Please estimate the sample size based on the assumption: 
80% power, two-sided χ2 test without continuity correction, significance level of 0.025, 15% dropout rate.
Sample size calculation
        According to a previous study, placebo is associated with high rates of resolution in a functional bowel disorder. Assuming that a difference of at least 30% between acupuncture and placebo is needed for a clinically important outcome, 51 patients per treatment group were deemed sufficient to achieve 80% power in detecting a treatment difference, based on a two-sided Ï2 test without continuity correction at a significance level of 0.025 (used to maintain the overall significance level at 5%). Further assuming a 15% dropout rate, we concluded that we needed to recruit a total of 120 patients (60 per arm) for this trial to ensure statistically significant results. The calculation was performed using the StudySize 3.0 software (V. Frolunda, Sweden).