Psychometric Validation of OAB-q

The OAB-q has been validated in diverse clinical and community samples of over 2500 total participants, thereby capturing the range of mild to severe OAB symptoms and HRQL impact.

Among both continent and incontinent OAB patients, the OAB-q has consistently demonstrated good internal consistency reliability, test-retest reliability, concurrent validity, discriminant validity, and responsiveness to treatment-related change.

Reliability

The OAB-q has demonstrated high internal consistency reliability in both clinical and community samples, with Cronbach's α in various samples ranging from 0.86 to 0.93 for the symptom bother scale and 0.75 to 0.96 for the HRQL subscales (Coyne et al. 2002).

The OAB-q has demonstrated good test-retest reliability (reproducibility) with intraclass correlation coefficients in the moderate to high range between assessments two weeks apart (all subscales = 0.83) (Matza et al. 2005).

Validity

The OAB-q has demonstrated criterion validity through statistically significant correlations with previously established patient-reported outcome measures (e.g., the SF-36) and clinical data (Coyne et al. 2002). OAB-q subscales have been shown to discriminate among continent OAB patients, incontinent OAB patients, and controls without OAB (Coyne et al. 2002). The OAB-q has also shown discriminant validity in that it distinguishes among patients with varying levels of urge intensity, micturition frequency, and frequency of nocturia episodes (Coyne et al. 2003; Coyne et al. 2003; Coyne et al. 2004).

Responsiveness

Responsiveness to treatment-related change has been assessed using data from a large 12-week clinical trial. The OAB-q was highly responsive with subscale effect sizes ranging from 0.44 (social interaction) to 1.2 (symptom bother).  A reduction of > 3 urgency episodes, > 3 micturitions, or > 1 incontinence episode per day resulted in significant score changes in all OAB-q subscales (p <0.05).  Improvements in OAB-q scales were associated with changes in patient and physician perceptions of treatment benefit. (Coyne et al. 2005).