Here is the design of a clinical trial:

Official Title: Diluted VAsopressin During Robot-assisted Laparoscopic myomEctomy for dimiNishing Blood Loss According To the Dilution Concentration of Normal salINE: a Randomized Controlled Pilot Study

Included conditions:
- Uterine Leiomyoma

Study Armgroups:
- {'label': 'Diluted Vasopressin Group 1', 'type': 'ACTIVE_COMPARATOR', 'description': 'During robot-assisted laparoscopic myomectomy, diluted vasopressin (a solution prepared by mixing 20 units of vasopressin with 50 ml of normal saline to make a total of 100 ml) was injected before uterine serosal incision.', 'interventionNames': ['Drug: Vasopressin']}
- {'label': 'Diluted Vasopressin Group 2', 'type': 'ACTIVE_COMPARATOR', 'description': 'During robot-assisted laparoscopic myomectomy, diluted vasopressin (a solution prepared by mixing 20 units of vasopressin with 200 ml of normal saline to make a total of 100 m) was injected before uterine serosal incision.', 'interventionNames': ['Drug: Vasopressin']}
- {'label': 'Diluted Vasopressin Group 3', 'type': 'ACTIVE_COMPARATOR', 'description': 'During robot-assisted laparoscopic myomectomy, diluted vasopressin (a solution prepared by mixing 20 units of vasopressin with 400 ml of normal saline to make a total of 100 m) was injected before uterine serosal incision.', 'interventionNames': ['Drug: Vasopressin']}

Interventions:
- {'type': 'DRUG', 'name': 'Vasopressin', 'description': 'During robot-assisted laparoscopic myomectomy, vasopressin diluted to different concentrations will be injected before uterine serosal incision.', 'armGroupLabels': ['Diluted Vasopressin Group 1', 'Diluted Vasopressin Group 2', 'Diluted Vasopressin Group 3'], 'otherNames': ['Vasopressin 20U']}

Primary Outcomes:
- {'measure': 'Estimated blood loss (EBL) during operation', 'description': 'The volume of blood loss will be estimated by using simple visual assessment technique referring to irrigation bottle', 'timeFrame': 'during operation'}

Please estimate the sample size based on the assumption: 
A 10% drop-out rate is assumed. Statistical analyses will use SPSS software V.25.0. Measurement data will be described in mean and SD or median and IQR, and categorical variables as number and percentage. The Kruskal-Wallis H test will analyze the difference in blood loss between the three groups. The incidence of side effects will be compared using the χ2 test or Fisher’s exact test. A p<0.05 is considered statistically significant.
Sample size
      Since this study is conducted as a pilot study, we did not separately calculate the sample size. The present pilot study examines the feasibility of a full randomised clinical trial of proper dilution level of vasopressin for RALM and determines the effect size for further large-scale studies. Based on a previous report, we plan to allocate 12 subjects per group for randomisation, and a total of 36 subjects are required.23 With a 10% drop-out rate and 1 subject per group, we aim to target 39 subjects.
      
        Statistical methods
        For the statistical analyses, we will use SPSS software V.25.0 (SPSS). Measurement data will be described in mean and SD or median and IQR, and categorical variables as number and percentage. The difference in blood loss between the three groups was analysed using the Kruskal-Wallis H test. The incidence of side effects between each group is compared and evaluated using the Ï2 test or Fisherâs exact test. A p<0.05 is considered statistically significant.
      
      
        Ethics and dissemination
        The Institutional Review Board has approved this pilot study of the Seoul National University Hospital (No. H-2011-107-1174). The current protocol version is 1.3. Even though vasopressin has already been approved for marketing and is used in clinical practice, the use of vasopressin to reduce bleeding in myomectomy has not been approved up to now. Thus, this clinical trial has been separately approved by the Korean Ministry of Food and Drug Safety (No. 33696).
        The confidentiality of personal information will be protected. All of the personal identification information will be deleted. Each participant is assigned a study identification number at enrolment. Data will be handled by the study identification number. Before participation, patients will receive detailed information about the purpose and possible consequences of the trial. Written informed consent will be obtained from each participant before enrolment by the investigators. Finally, the results of this study will be published in peer-reviewed journals and be presented at academic conferences.
      
      
        Patient and public involvement
        Patients and/or the public were not involved in the design, or conduct, or reporting, or dissemination plans of this research.