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Validation of acoustic voided volume measure: a pilot prospective study
Hwanik Kim1,2, Changhee Ye1, Gyoohwan Jung1
1Department of Urology, Seoul National University Bundang Hospital, Seongnam, Korea.
Purpose:
We evaluated the accuracy and reliability of a new smartphone-based acoustic voided volume (VV) measurement application compared to VV estimation based on the measurement of urine volume in a bladder by ultrasound bladder scan.
Patients And Methods:
A total of 53 subjects from 01/2021 to 09/2021 were prospectively enrolled. Bladder scan-based VV estimation is based on the difference in the volume of urine in a bladder measured before urination and volume measured after urination. The acoustic VV measurement is based on smartphone-based acoustic VV measurement mobile application. VV estimates for the same void were compared between two techniques. Urinary measures were obtained from 49 male subjects resulting in a total of 245 measurements for analysis. VV measures were compared using Pearson's correlation coefficient (PCC), evaluation of observed versus predicted VV measures using linear regression fit indices, and Bland-Altman method.
Results:
VV between the two techniques revealed strong correlation (PCC 0.811, p < 0.001). Means of the number of measurements per patient and inpatient days for measurements analyzed are 5 and 2.7, respectively. In 245 measurements, VV measured by bladder scan is 238.69 ± 122.32 mL, VV measured by mobile application is 254.69 ± 119.28 mL, and their difference of two measurements is 16 ± 74.29 mL.
Conclusion:
Through the comparison with VV estimated by ultrasound bladder scan, which is a technology to measure the urine volume in a bladder, it was confirmed that the smartphone-based acoustic VV measurement application proudP® is accurate.
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