Validation of a 3 day electronic bladder diary as an app for smart-phone

To validate an electronic 3-day bladder diary (BD) as an easy-to-use app for smart-phone (eDM3d).

Descriptive and cross-sectional prospective study. One hundred and thirty-six patients with overactive bladder syndrome (OABs) or nocturia who had a smart-phone and attended the urology clinics of a tertiary hospital from June to November 2017 were included. Patients filled the eDM3d (test) and the Spanish validated paper BD (DM3d) and questionnaires ICIQ-UISF and BASQ during the first week. Two weeks later, they repeated the eDM3d (retest). We assessed feasibility of the eDM3d (percentage of variables completed), test-retest reliability (qualitative variables: McNemar test; quantitative variables: ICC), paper-app correlation (qualitative variables: Kappa index; quantitative variables: ICC) and convergent validity (correlation between eDM3d and questionnaires, Spearman's rank test). Patients answered a question about satisfaction: "If you had to repeat a BD again, would you choose paper or the app version?"

One hundred and twenty-three (90.4%) participants completed all the variables of the first eDM3d. There were no significant differences in the proportion of patients classified as positive for each symptom between test and retest. ICC ranged from 0.73 to 0.94 for all variables (P < 0.001) in the test-retest assessment. Paper-app correlation was good to excellent for all variables (ICC 0.76-0.95, P < 0.001; Kappa index 0.56-0.84, P < 0.001). Correlation between the eDM3d and the questionnaires ranged from 0.23 to 0.6 (P < 0.01). 120 (88.2%) patients would choose the eDM3d if they had to repeat a BD.

The eDM3d presents suitable feasibility, reliability, and validity to assess patients with OABs or nocturia who have a smart-phone.