Developing and Evaluating a WeChat-Based Applet Fluid Intake Reminder on Enhancing Fluid Adherence in Postoperative Patients With Urinary Calculi: Protocol for a Randomized Controlled Trial.

Background: Urinary calculi (UC), affecting 1%-13% globally, pose a significant health burden due to high recurrence rates (up to 50% within 10 years) and substantial health care costs. Adequate fluid intake is a cornerstone of prevention; yet, its adherence remains poor due to forgetfulness, lifestyle barriers, and limited patient education. Existing mobile health interventions for UC prevention often lack medical oversight and clinical validation. WeChat-based digital therapeutic intervention may have a positive effect on fluid adherence in this patient group. Objective: Our objective is to develop a WeChat applet to improve hydration behavior and reduce stone recurrence among postoperative patients with UC. Methods: This is an open-label, 2-arm, parallel-group randomized controlled trial. We will recruit 148 participants from China's tertiary hospital and randomly allocate them in a ratio of 1:1 to the intervention or control group. The intervention group received standard postoperative care supplemented by the WeChat-Based Applet Fluid Intake Reminder (WAFIR), which delivers personalized fluid intake reminders, urine color monitoring, 24-hour fluid intake and urine output tracking, and evidence-based educational content on hydration and urolithiasis management. The control group receives standard care of general discharge instructions from nurses. The primary outcome is the fluid adherence, measured by 24-hour fluid intake and urine volume; secondary outcome measures are the Wisconsin Stone Quality of Life Questionnaire, Patient Health Questionnaire-9, Electronic Health Literacy Scale, physical activity (International Physical Activity Questionnaire-Short Form), and recurrence rate of UC. Outcomes are measured before intervention (T0) and after a 1-month (T1) and 3-month (T2) follow-up period. Intention-to-treat analysis, 2-tailed t tests, and repeated measures ANOVA will be used to compare outcomes; statistical significance is set at a P<.05 significance threshold. The study was approved by the ethics review board in December 2024. Results: The development of WAFIR, conducted in collaboration with stakeholders, was finalized in February 2025. Recruitment commenced on March 1, 2025; data collection was completed in September 2025, and data analysis was analyzed in December 2025. Dissemination of findings is planned through conferences and publications in 2026. Conclusions: This research evaluates the effectiveness of a nurse-led, evidence-based digital therapeutic intervention, WAFIR, in overcoming fluid adherence barriers among postoperative patients following urolithiasis surgery, aiming to increase daily fluid intake and urine output, reduce recurrence rates, enhance quality of life, and generate empirical evidence for its application in urology care, thereby optimizing postoperative management within clinical settings.