Uroflowmetry is a noninvasive technique for determining the volume of urine discharged over a period. This enables the assessment of void volume (voided volume), voiding time, average flow rates (Qavg), and maximum flow rate (Qmax), as well as aberrant flow patterns. Uroflowmetry is now an in-office method used to determine the parameters of urine excretion while respecting patient privacy.
When uroflowmetry is performed, the patient urinates into a special bucket in a private location after a normal to strong urge to void. If an abnormal void arises, frequent evaluations are necessary. Therefore, precision in uroflowmetry requires time, space, and privacy, which may be challenging in a clinic/hospital setting. Moreover, some individuals may have trouble urinating in a foreign environment or due to a painful or excessive voiding duration, necessitating repeated tests to obtain correct results.
Latest uroflowmetry technologies have been developed in response to the need for easy and portable home devices. These advancements include mobile acoustic uroflowmetry (sonouroflowmetry), optical uroflowmetry, and video-based emptying devices. In contrast to the standard approach, acoustic uroflowmetry may be done at home using a smartphone rather than an outpatient clinic-based uroflowmetry. The method's actual strength is in its adaptability and simplicity.
Urine flow rate was first measured using a weight transducer, rotating disc, or capacitor change. It is feasible to assess urine flow by measuring the acoustic fluctuations at the air-water interface caused by the urine stream's interaction with the toilet water surface. When Hitt et al. used sound to quantify urine flow in 2009, they established the viability of connecting acoustic and flow parameters. In 2011, Zvarova et al. released comparable sonouroflowmetry findings. They observed that whereas men had equal flow curves, there were modest differences in the time of voiding and rate of flow when compared to standard uroflowmetry. Previously published research examined a novel sono- uroflowmetry technique for describing and forecasting urine flow rate by capturing the sound of urinating using a smartphone. In our previous attempt to look for predeceasing systematic reviews from multiple bibliographic databases, we got no results on finding one, thus, with multiple papers published on this unique instrument.  To the best of our knowledge, there has been no systematic review reported which compares sono uroflowmetry with conventional uroflowmetry. With no previous reviews available, we conducted a systematic review to assess the accuracy and reliability of acoustic and traditional uroflowmetry, in hope to enlighten further research in the future.

This review aimed in evaluating the accuracy and reliability of sono-uroflowmetry compared to conventional uroflowmetry. Electronic databases searching were done using pre-specified search strategy to retrieve articles related with uroflowmetry. In addition, hand-search strategy was used to identify additional articles. Studies with participants who had undergone sono-uroflowmetry were included. Voided volume, voiding duration, maximum flow rate, and average flow rate were identified and used to determine the outcomes of measurement. The quality of included articles was conducted using Checklist for Diagnostic Test Accuracy Studies by JBI.

Voided volume
Four studies reported voided volume in their studies. Across these studies, two studies reported moderate correlation of the voided volume between sonouroflowmetry as compared to the conventional uroflowmetry. However, high correlation of the voided volume between sono uroflowmetry as compared to the conventional uroflowmetry was reported in one study. Despite male participants had moderate-to-high correlation between sonouroflowmetry and conventional uroflowmetry in the voided volume, similar finding was not obtained from Lee et al.Click or tap here to enter text. Even so, female participants were found to have significant difference in the voided volume.
Voiding time
Three studies reported voiding time in their studies. Significant correlation between acoustic uroflowmetry and conventional uroflowmetry were reported by Song et al. However, other two studies did not report significant changes in the voiding time. Helou et al. reported that high error was obtained if the voiding duration were not long enough, while Lee et al reported significant difference in the female population but not in the male population.
Average urine flow rate
Four studies reported average flow rate in their studies.Three studies reported highly significant correlation in the average flow rate between sono- and conventional uroflowmetry in male populations. Similar with two previous variables, the difference  between sono and convention uroflowmetry were only significant in female population but not in male population.
Maximum flow rate
Five studies reported maximum flow rate in their studies. All studies reported significant difference in the maximum flow rate between sono and conventional uroflowmetry.

Uroflowmetry is a noninvasive technique for determining the volume of urine discharged over a period. This enables the assessment of void volume (voided volume), voiding time, average flow rates (Qavg), and maximum flow rate (Qmax), as well as aberrant flow patterns. Uroflowmetry is now an in-office method used to determine the parameters of urine excretion while respecting patient privacy.
When uroflowmetry is performed, the patient urinates into a special bucket in a private location after a normal to strong urge to void. If an abnormal void arises, frequent evaluations are necessary. Therefore, precision in uroflowmetry requires time, space, and privacy, which may be challenging in a clinic/hospital setting. Moreover, some individuals may have trouble urinating in a foreign environment or due to a painful or excessive voiding duration, necessitating repeated tests to obtain correct results.
Latest uroflowmetry technologies have been developed in response to the need for easy and portable home devices. These advancements include mobile acoustic uroflowmetry (sonouroflowmetry), optical uroflowmetry, and video-based emptying devices. In contrast to the standard approach, acoustic uroflowmetry may be done at home using a smartphone rather than an outpatient clinic-based uroflowmetry. The method's actual strength is in its adaptability and simplicity.
Urine flow rate was first measured using a weight transducer, rotating disc, or capacitor change. It is feasible to assess urine flow by measuring the acoustic fluctuations at the air-water interface caused by the urine stream's interaction with the toilet water surface. When Hitt et al. used sound to quantify urine flow in 2009, they established the viability of connecting acoustic and flow parameters. In 2011, Zvarova et al. released comparable sonouroflowmetry findings. They observed that whereas men had equal flow curves, there were modest differences in the time of voiding and rate of flow when compared to standard uroflowmetry. Previously published research examined a novel sono- uroflowmetry technique for describing and forecasting urine flow rate by capturing the sound of urinating using a smartphone. In our previous attempt to look for predeceasing systematic reviews from multiple bibliographic databases, we got no results on finding one, thus, with multiple papers published on this unique instrument.  To the best of our knowledge, there has been no systematic review reported which compares sono uroflowmetry with conventional uroflowmetry. With no previous reviews available, we conducted a systematic review to assess the accuracy and reliability of acoustic and traditional uroflowmetry, in hope to enlighten further research in the future.

Sonouroflowmetry was shown to be a promising alternative of urine flow measurement. However, further research with good quality design is necessary to evaluate the practicality of sonouroflowmetry in everyday life. Studies in female population, randomized controlled trials, and meta-analyses need to be conducted to determine the true effect of the intervention towards the outcome.

N. Alothmany, H. Mosli, · Mehdi Shokoueinejad, R. Alkashgari, M. Chiang, and J. G. Webster, “Critical Review of Uroflowmetry Methods,” Journal of Medical and Biological Engineering, vol. 38, pp. 685–696, 2018, doi: 10.1007/s40846-018-0375-0.
D. Hitt, K. Zvarova, and P. Zvara, “Urinary flow measurements via acoustic signatures with application to telemedicine,” Aerospace Research Central, Jun. 2012.
M. Shokoueinejad et al., “Video Voiding Device for Diagnosing Lower Urinary Tract Dysfunction in Men,” Journal of Medical and Biological Engineering, vol. 37, doi: 10.1007/s40846-017-0283-8.