Rationale and design of the validation of bladder health instrument for evaluation in women (VIEW) protocol

BACKGROUND: Bladder health is an understudied state and difficult to measure due to lack of valid and reliable instruments. While condition specific questionnaires assess presence, severity and degree of bother from lower urinary tract symptoms, the absence of symptoms is insufficient to assume bladder health. This study describes the methodology used to validate a novel bladder health instrument to measure the spectrum of bladder health from very healthy to very unhealthy in population based and clinical research. METHODS: Three samples of women are being recruited: a sample from a nationally representative general population and two locally recruited clinical center samples—women with a targeted range of symptom severity and type, and a postpartum group. The general population sample includes 694 women, 18 years or older, randomly selected from a US Postal delivery sequence file. Participants are randomly assigned to electronic or paper versions of the bladder health instrument along with a battery of criterion questionnaires and a demographic survey; followed by a retest or a two-day voiding symptom diary. A total of 354 women around 7 clinical centers are being recruited across a spectrum of self-reported symptoms and randomized to mode of completion. They complete the two-day voiding symptom diary as well as a one-day frequency volume diary prior to an in-person evaluation with a standardized cough stress test, non-invasive urine flowmetry, chemical urine analysis and post void residual measurement. Independent judge ratings of bladder health are obtained by interview with a qualified health care provider. A total of 154 postpartum women recruited around 6 of the centers are completing similar assessments within 6–12 weeks postpartum. Dimensional validity will be evaluated using factor analysis and principal components analysis with varimax rotation, and internal consistency with Cronbach’s alpha. Criterion validity will be assessed using multitrait-multimethod matrix including correlations across multiple data sources and multiple types of measures. DISCUSSION: We aim to validate a bladder health instrument to measure the degree of bladder health within the general population and among women (including postpartum) recruited from local clinical centers. Trial registration NCT04016298 Posted July 11, 2019 (https://www.clinicaltrials.gov/ct2/show/NCT04016298?cond=bladder+health&draw=2&rank=1).