The validity and reliability of the neurogenic bladder symptom score

The neurogenic bladder symptom score is a tool to measure urinary symptoms and consequences in patients with acquired or congenital neurogenic bladder. We describe score validity and reliability.

Exploratory factor analysis was used to assess item variability and subscale structure. Reliability was assessed by the Cronbach α and correlation with retest data. Validity was assessed with a priori hypotheses specifying relationships with the AUASS (American Urological Association symptom score), ICIQ-UI (International Consultation on Incontinence-Urinary Incontinence) and urinary specific quality of life SF-Qualiveen questionnaires, and a self-assessed global bladder problem score. Known groups analysis was used to further assess construct validity.

A cohort of 230 patients with spinal cord injury (35%), multiple sclerosis (59%) and congenital neurogenic bladder (6%) were included in study. Factor analysis suggested 3 neurogenic bladder symptom score domains, including incontinence, storage and voiding symptoms, and consequences. Overall internal consistency was high (Cronbach α=0.89). Test-rest reliability was also excellent with an ICC2,1 of 0.91. Validity was demonstrated by the confirmation of hypothesized correlations with the AUASS, ICIQ-UI and SF-Qualiveen, and significant differences in neurogenic bladder symptom score scores among known groups. Patients with a history of seeing a urologist had a significantly higher mean score, as did those with a higher global bladder problem score (22.1 vs 17.1 and 22.1 vs 12.6, respectively, each p<0.001).

The neurogenic bladder symptom score, developed specifically to assess symptoms and consequences associated with neurogenic bladder dysfunction, has appropriate psychometric properties. Depending on the measurement need individual domains may be selected or it can be used as a comprehensive score.