The Overactive Bladder Symptom Score, International Prostate Symptom Score–Storage Subscore, and Urgency Severity Score in Patients With Overactive Bladder and Hypersensitive Bladder: Which Scoring System is Best?

PURPOSE: To evaluate the correlations among the Overactive Bladder Symptom Score (OABSS), International Prostate Symptom Score–Storage Subscore (IPSS-S), and the modified Urgency Severity Scale (USS) in patients with overactive bladder (OAB) and hypersensitive bladder (HSB) and to identify the most useful diagnostic tool for classifying the severity of OAB. METHODS: We retrospectively reviewed the charts of consecutive patients with OAB who visited our urologic clinics for treatment. All patients underwent a detailed history, physical examination, urinalysis, uroflowmetry, and postvoid residual volume measurement, and completed a 3-day voiding diary. All patients answered the Chinese versions of the IPSS, OABSS, and USS, according to which they were classified as having wet or dry OAB based on whether their chief complaint was urgency urinary incontinence or urgency without incontinence. HSB was defined as a functional bladder capacity <350 mL and a USS of 0 or 1. RESULTS: The records of 325 OAB patients (99 women and 226 men) were reviewed. The OAB subgroups included HSB (n=31), OAB-dry (n=74), and OAB-wet (n=220). One-way analysis of variance showed significant differences among the OAB subgroups evaluated using each scoring system. Each scoring system was significantly correlated with the OAB subgroups. The Spearman rho was 0.983 for the USS, 0.651 for the OABSS, and 0.428 for the IPSS-S. CONCLUSIONS: The IPSS-S, OABSS, and USS showed good correlations with the OAB subgroups. Their ranking in terms of discriminant ability for classifying OAB severity as HSB, OAB-dry, and OAB-wet was USS>OABSS>IPSS-S. The simplest survey, the USS, with a single item scored from 0 to 4, had the strongest correlation with the OAB severity subgroups.