Validity of the Traditional Chinese Version of the King's Health Questionnaire for Taiwanese Patients With an Overactive Bladder

ObjectiveIn this study, we tested the validity of the 2009 Chinese version of the King's Health Questionnaire (KHQ) in patients with an overactive bladder (OAB).Materials and MethodsIn 2009, the Taiwan Continence Society commenced linguistic validation and other elements of production required for a Chinese version of the KHQ. Data for the psychometric assessment came from a multicenter clinical trial. Patients who visited urology clinics with OAB and symptoms of urgency frequency with or without urge incontinence were asked to fill out the KHQ at the initial visit and again 1 week later. The internal consistency was measured by Cronbach's alpha statistics. The test-retest method was used to compare the reliability of responses of the two completed questionnaires using Spearman's rank correlation coefficient. An alpha value > 0.70 was considered acceptable.ResultsIn total, 55 patients were enrolled, including 37 women and 18 men. Forty-seven (85.5%) patients correctly completed both questionnaires. The alpha values exceeded the minimum requirement for reliability in all domains of the questionnaire, except for the severity measure item (0.60). The internal consistency was also consistently high between tests 1 and 2 in all domains. Test-retest reliability also showed significant correlations between the two tests in all domains.ConclusionThis study demonstrates that the 2009 Chinese version of the KHQ is a reliable instrument for assessing health-related quality of life in patients with OAB.