Randomization and Masking
The trial used a simple randomization approach. A 1:1 random assignment sequence was generated via a table of random numbers by a research assistant who was not involved in the study and was placed into sequentially numbered, opaque, and sealed envelopes. When each participant was enrolled, the intervention manager opened the envelope in sequence, and the participant was assigned to the experimental group, which received oral PFMT instructions and the UIW app intervention, or the control group, which received oral PFMT instructions. Owing to the nature of the app-based intervention and self-reported outcomes, neither the participants nor the research staff were blinded to the intervention.