Agreement and Reliability of Patient-measured Postvoid Residual Bladder Volumes

Area of Science:

• Urology
• Medical Devices
• Remote Patient Monitoring

Background:

• Postvoid residual bladder volume (PVR) measurement is crucial for managing voiding dysfunction.
• Current PVR measurement often requires healthcare visits, limiting remote monitoring capabilities.
• Smart-device portable ultrasound offers a potential solution for at-home PVR assessment.

Purpose of the Study:

• To evaluate the reliability and agreement of patient self-measurement of PVR using a portable ultrasound system.
• To compare patient self-measurement with provider measurements.
• To assess patient preferences for self-measurement versus provider measurement.

Main Methods:

• Fifty patients undergoing urology outpatient visits participated.
• Providers and patients used a portable ultrasound device (in two modes) and a standard bladder scanner for PVR measurements.
• Reliability was assessed using intraclass correlation, and agreement using Bland-Altman analyses.

Main Results:

• Patient self-measurement demonstrated high reliability (intraclass correlations 0.95–0.98).
• Limits of agreement between self-measurement and standard scanner exceeded the 50 mL threshold.
• A majority of patients (74%) preferred self-measurement over provider measurement.

Conclusions:

• Patient self-measurement of PVR with portable ultrasound is feasible, reliable, and preferred.
• While agreement limits require consideration, this technology supports remote monitoring for voiding dysfunction.
• Further research should account for inherent ultrasound measurement errors in longitudinal studies.