Psychometric properties of the korean version of the overactive bladder questionnaire (OAB-q) in a Korean population

Purpose: Psychometric properties of the overactive bladder questionnaire (OAB-q) were recently examined. However, since the cross-cultural adaptation of a non-English version of the OAB-q has never been demonstrated, we evaluated the psychometric properties of a Korean version of the OAB-q in a Korean population with OAB. Methods: A prospective cohort study involving 116 women with 58 OAB and 58 control subjects was performed and convergent validity was assessed. Total and subscale OAB-q scores of the control and OAB groups were compared to their sensitivity to score changes before and after administering anti-cholinergic medication for 12 weeks. Short form 36 and King's health questionnaire (KHQ) were also used for comparison or correlation. Results: Assessment of face validity showed that the Korean version of the OAB-q was reasonable with OAB-q subscale scores being significantly different between the control and patient groups. Significant correlation (range, -0.29 to -0.81) was found between the OAB-q scores and KHQ results for the OAB patients. Cronbach's alpha coefficients (range, 0.77 to 0.95) indicated excellent internal consistency and test-retest analysis involving 35 OAB patients showed that each questions as well as subscale scores were reproducible. Each score of OAB-q also showed statistically significant sensitivity to changes following anti-muscarinic treatment for OAB (n=27, P<0.001 except for social, P=0.059). Conclusions: The Korean version of the OAB-q is a valid and reliable instrument to measure outcomes in Korean patients with OAB.