American Urological Association-symptom Index Lacks Internal Consistency for Measuring Storage Voiding Symptoms

To examine the validity of the American Urological Association Symptom Index (AUA-SI) to assess varied lower urinary tract symptoms in men and women.

Internal consistency and test-retest reliability of the AUA-SI were assessed in a community-dwelling cohort representative of the United States population (n = 1551) and a national care-seeking cohort (n = 1083). We also examined correlations of the AUA-SI subscale and total scores with validated urinary symptom severity measures, the lower urinary tract symptoms tool (LUTS tool), and gender-specific versions of the International Consultation on Incontinence Questionnaire-lower urinary tract symptoms (ICIQ-LUTS).

Men demonstrated more severe voiding phase symptoms, while women exhibited more storage phase symptoms. Internal consistency of the AUA-SI, measured by McDonald's omega, was >0.7 for the assessment of voiding-phase lower urinary tract symptoms, but performed poorly for storage symptoms at 0.61 and 0.56 for men and women, respectively. Spearman's correlation coefficients between the AUA-SI and other survey instruments assessing urinary symptoms were poor, particularly for women and storage lower urinary tract symptoms-related quality of life.

The AUA-SI is a validated symptom score with high internal consistency and reliability for assessing men with benign prostatic hyperplasia, but is broadly used to assess women and men with lower urinary tract symptoms. While validated for use in men with benign prostatic hyperplasia, the AUA-SI performs poorly in evaluating storage lower urinary tract symptoms and related quality-of-life, particularly in women. Clinicians should use caution in non-validated uses of the AUA-SI, particularly for female storage voiding dysfunction.