BACKGROUND: The voiding diary is a crucial tool for assessing fluid intake and urinary habits, commonly used to aid in diagnosing urinary dysfunctions in the pediatric population. However, since the voiding diary relies on the patient or their guardian for completion, it becomes subject to incorrect data entries, compromising its evaluation and reliability. METHODS: This was an open, prospective, controlled, randomized, and single-center clinical trial that included children aged 5 to 17 years without cognitive or neurogenic impairments, who were not illiterate and not using diapers. Participants were instructed to fill out the voiding diary for a 48-hour period, with randomization conducted virtually using computer-generated numbers at the initial consultation. Patients in the control group received only outpatient explanations on how to complete the voiding diary without the provision of explanatory audiovisual materials, while patients in the test group received similar explanations to the control group and an explanatory video created by the study team on the correct way to complete the diary. A structured questionnaire was administered during follow-up consultations to evaluate the diary data in both groups. RESULTS: The study sample consisted of 29 patients, with 4 (13.79%) patients not completing the voiding diary, including 3 (20.00%) patients from the control group and 1 (07.14%) patient from the test group. The mean age was 9.65 years (± 2.74 years), with 14 (48.28%) males and 15 (51.72%) females. Regarding the intervention, 14 (48.28%) patients were in the test group and 15 (51.72%) patients were in the control group. Concerning the correct completion rate of the voiding diary, 18 (62.06%) diaries were filled out adequately. When comparing the accurate completion of the diary between groups with different interventions, it was observed that 9 (60.0%) of the patients in the control group and 9 (64.28%) of the patients in the test group completed the voiding diary correctly (p=1.000). The patients in the test group showed a better understanding of the required number of days for correctly completing the diary, with 12 (92.30%) of the patients in this group filling out the diary for a period of 2 days, while 7 (46.66%) of the patients in the control group did the same (p=0.016). These are partial results. CONCLUSIONS: The results reveal that the reliability of voiding diary completion in pediatric patients is a challenging issue, with just over half of the participants filling out the diary correctly. This underscores the difficulty many patients face in translating medical instructions into practical actions. Although the use of an explanatory video was perceived as useful by patients, there was no statistically significant improvement in the accuracy of completion compared to traditional instructions. However, patients who watched the video demonstrated a better understanding of the required duration for correct diary completion.
