Which single-item measures of overactive bladder symptom treatment correlate best with patient satisfaction?

While complex symptom scales are important research tools, simpler, preferably single item scales may be more useful for routine clinical practise in the evaluation of patients with overactive bladder syndrome (OAB). This study aimed to compare multiple single-item scales at baseline and after treatment with patient-reported overall rating of treatment efficacy.

In a pre-planned secondary analysis of a previously reported observational study, 4,450 patients were evaluated at baseline and after 12 weeks open-label treatment with solifenacin. Apart from episode counting for classical OAB symptoms, the following single-item rating scales were applied: Indevus Urgency Severity Scale, Urgency Perception Scale, a Visual Analog Scale (VAS), quality of life question of the IPSS, and general health and bladder problem questions of the King's Health Questionnaire (KHQ).

At baseline OAB symptoms correlated at best moderately with each (r = 0.285-0.508) other or with any of the rating scales (r = 0.060-0.399). Pair-wise correlations between treatment-associated symptom or scale improvements tended to be tighter (r = 0.225-0.588). When compared to patient-reported efficacy, the VAS (r = 0.487) and the bladder problem question of the KHQ (r = 0.452) showed the tightest correlation, whereas all symptom and rating scale improvements exhibited poor correlation with patient-reported tolerability (r ≤ 0.283).

The VAS and the bladder problem question of the KHQ show the greatest promise as single-item scales to assess problem intensity in OAB patients.