Validity and reliability study of a free mobile app for assessing voiding habits

Paper-based bladder diaries are widely used to assess urinary symptoms, including urinary incontinence (UI). Patient adherence to completing them is a challenge. Mobile applications (apps) have become accessible and low-cost alternative tools to improve clinical data collection; however, their accuracy still lacks evidence.

To validate a mobile app to assess voiding habits.

Clinimetric property study of the bladder diary app "Minha Bexiga." After the app's usability has been evaluated by the System Usability Score, women with and without UI, aged over 18 and who own smartphones, used the "Minha Bexiga" app and a paper bladder diary for three consecutive days to test criterion validity via correlation between scores obtained from the paper and electronic diaries. After 7 days, the women used only the "Minha Bexiga" app again to test reliability via intraclass correlation coefficient (ICC) test.

A total of 70 women were included (38.5 years (28-48.5), 30 % had up to 11 years of education, 39 with UI and 31 without UI). The "Minha Bexiga" app showed substantial reliability (ICC = 0.85 (95 % CI 0.77-0.90)) and strong validity (Rho = 0.67; p < 0.001). In the sub-analysis, grouping all women by education level and age, the validity of the app has been observed for women with more than 11 years of education (Rho = 0.90; p < 0.001), with no relation to age. Reliability was excellent for women aging over 40 years, with no relation to education level (ICC = 0.90 (95 %CI 0.80-0.94)). The usability of the app was considered acceptable by women.

The "Minha Bexiga" app may be a useful tool for assessing voiding habits. However, its use seems to be more accurate for women over 40 years of age and with 11 years of education.