An ambulatory sensor-based system for quantification of nighttime micturition for accurate nocturia assessment

Nocturia is a widespread condition where patients need to micturate frequently during the nighttime. In order to define treatment and measure therapeutic success in nocturia, questionnaires are traditionally used for ambulatory assessment. However, questionnaires were reported to suffer from compliance, embarrassment and subjective bias. An automatic sensor-based system for quantification of nighttime micturition for accurate nocturia assessment would not suffer from these disadvantages, and its development was therefore the purpose of this study. We defined a sensor-based system for ambulatory use, consisting of a sensor watch and a room occupancy sensor. Using this system, we so far collected data from 6 participants and 82 nights in an ongoing study. We report the details of the system, as well as the data analysis. The system is very accurate, with an average misdetection rate of 0.32 and a mean absolute deviation of 3.8 % when comparing the average number of nighttime micturitions. This novel sensor-based nighttime micturition quantification system has the potential to be used as an objective ambulatory assessment tool for nocturia diagnosis and treatment.