Interstitial cystitis/painful bladder syndrome (IC/PBS) at present is a symptom-based diagnosis. The Interstitial Cystitis Symptom Index (ICSI), also known as the O’Leary-Sant Symptom Index, is a widely used scale that assesses the four cardinal symptoms of IC/PBS (ie, bladder pain, urgency, frequency, and nocturia), by asking how often each is experienced. In an ongoing case-control study of recent-onset IC/PBS, we compared the ICSI with a series of questions that addressed the severity of these symptoms.

Recruiting nationally, we enrolled women with IC/PBS symptoms of 12 months’ duration or less. We assessed the severity of pain, frequency, and urgency using Likert and categorical scales, and how often these symptoms were experienced using the ICSI. We compared these scales by frequency distributions and interscale correlations.

In 138 women with recent-onset IC/PBS, the scores for frequency were correlated and, for pain, appeared to be complementary. However, for urgency, the ICSI question of “the strong need to urinate with little or no warning” consistently yielded lower scores than the severity question of “the compelling urge to urinate that is difficult to postpone.” Some patients denied urgency to the ICSI question yet reported intense urgency to the severity question.

Compared with the severity question, the ICSI underestimated the prevalence and degree of urgency. This observation is consistent with the views of others that sudden urgency does not define the sensation experienced by many patients with IC/PBS. Clarifying this symptom description may assist in developing a usable case definition for IC/PBS.