Development and Validation of Symptom Score for Total Bladder-Bowel Dysfunction: Subscales for Overactive Bladder and Dysfunctional Voiding

Purpose: Bladder-bowel questionnaires are an important tool in diagnosing nonneurogenic bladder-bowel dysfunction in children. We report the validity and reliability of a bladder-bowel questionnaire that has been in clinical use at our institution for decades. Materials and Methods: The bladder-bowel questionnaire contains 13 questions, with answers ranging from never (score of 0) to daily (3). The questionnaire was answered by 139 healthy controls and 134 children 3 to 16 years old diagnosed with bladder-bowel dysfunction by a pediatric urologist/urotherapist. A subdiagnosis of overactive bladder or dysfunctional voiding was made in each patient. Bladder-bowel questionnaire scales were developed and evaluated against hypotheses of validity (known groups/convergent/discriminating) and reliability (internal consistency/retest reliability), sensitivity and specificity. Responsiveness was tested in 80 patients who answered the bladder-bowel questionnaire after treatment. Results: A total bladder-bowel dysfunction score scale demonstrated the ability to discriminate between patients with bladder-bowel dysfunction and healthy subjects. It resulted in a ROC curve with AUC of 0.96. The maximized sensitivity was 94% and specificity was 89% for a cutoff score of 7. Two subscales were identified referring to 6 filling phase items and 3 voiding phase items. When tested in patients with overactive bladder and dysfunctional voiding, respectively, multivariable scales performed sufficiently to discriminate between those with and without overactive bladder, and those with and without dysfunctional voiding. All of these scales fulfilled the evaluated requirements for validity and reliability. At 1 year after treatment all scale scores corresponded to patient improvement (p <0.0001), suggesting the bladder-bowel questionnaire can detect clinical change over time. Conclusions: The bladder-bowel questionnaire is valid and reliable for diagnosing bladder-bowel dysfunction in pediatric patients, and overactive bladder and dysfunctional voiding in those with bladder-bowel dysfunction.