Comparative study of the effectiveness and safety of cranberry with tamsulosin and placebo in improving stent-related symptoms in patients undergoing Double-J ureteral stent placement: a three-group randomized controlled trial

Comparison of the effectiveness and safety of cranberry, tamsulosin, and placebo in improving stent-related symptoms in patients undergoing Double-J ureteral stent placement

A controlled, parallel-group, triple-blind, randomized, phase 3 clinical trial on 96 patients. Graphpad.com was used for randomization via the online sealed envelope program.

The study will be performed in the Urology Department, Razi Educational and Medical Center in Rasht. This study is performed on 96 patients gradually and sequentially. Patients will be randomly assigned to 3 groups: cranberry, tamsulosin, and placebo. The patient, the researcher allocating the sample to treatment groups, and the analyst will be unaware of the type of patient grouping.

Inclusion criteria: age over 18 years, candidate for Double-J Ureteral Stent Placement; Exclusion criteria: Having bilateral stents, concurrent urinary tract infection, pregnancy, neurogenic bladder, overactive bladder syndrome, history of or current treatment for urinary incontinence, Lower urinary tract symptoms related to benign prostatic hyperplasia, chronic pelvic pain syndrome, use of anticholinergic, alpha-blockers, and analgesics drugs, major complications after urethroscopy surgery

Intervention group 1: Daily receiving one 500mg cranberry capsule of Dayan Pharmed Behin Tolid company, until stent removal; Intervention group 2: Daily receiving one 0.4mg tamsulosin for Tasnim Pharmaceutical Company, placed in cranberry-like coatings until stent removal; Intervention group 3: Receiving one placebo daily consisting of empty cranberry capsules filled with chickpea flour, until stent removal

Urinary symptoms including dysuria, hematuria, urinary frequency and nocturia; pain-related symptoms; sexual symptoms and dysfunction

Block randomization with blocks of 6 with a 1:1 ratio (in three groups A, B, and C) using the graphpad.com website and through the sealed envelope online program will be done. To assign the target group to one of the three study groups, the block randomization method with blocks of six will be used. Then, the participants will be allocated to one of the three groups in a 1:1 ratio according to the block randomization protocol (generated by graphpad.com website), in such a way that the researcher cannot predict which group of the intervention the next person will be placed in. In order to conceal the random assignment, the codes generated by the software will be placed in an envelope so that it is not clear which group the next person will be placed in. Concealed random assignment refers to the method used to perform the random sequence on study participants, in such a way that the assigned group is not known before the individual is assigned. In this study, the method of sealed opaque envelopes with a random sequence will be used. Based on the sample size of this study, a number of envelopes are prepared and each of the random sequences created is recorded on a card and the cards are placed inside the envelopes in order. In order to maintain the random sequence, the outer surface of the envelopes is numbered in the same order. Finally, the envelopes are glued shut and placed in a box in order. At the start of registration, based on the order in which eligible participants enter the study, one of the envelopes is opened in order and the assigned group of that participant is revealed.

Patients and researchers associated with patients are unaware of the patient's exposure. Each patient will be identified with a code that will be placed in an envelope. Researcher responsible for data collection (urology resident) places the patients in one of 3 groups based on random numbers generated in the software and after completing the checklist for them, each patient is identified with a code that is placed in an envelope (B, A or C). Then, the patients are referred to the Urology research center to receive the medicine (without knowing its type). The coating and appearance of all drugs are the same. Tamsulosin and placebo (Contains chickpea flour) are placed in empty cranberry capsules and will be packaged by one of the researchers (other than the researcher responsible for data collection and the researcher distributing the medicine) in one of the B, A, and C envelopes. The researcher distributing the medicine is unaware of the type of contents inside the medicine envelopes. The analyst will also be unaware of the type of grouping of the patients.