Validity and reliability of Thai version of Overactive Bladder Symptom Score

Abstract

Purpose: To examine the psychometric property of Overactive Bladder Symptom Score (OABSS) in Thai version. Methods: A descriptive study was conducted at urological clinic at faculty of Medicine, Vajira hospital, University of Bangkok Metropolis from August 2012 to February 2013. Sixty women aged over 18 year old diagnosed with overactive bladder by the definition of International Continence Society (ICS) were recruited. Of these women, they were interview by our medical staffs two session in a two-week interval using a self-completion questionnaires of OABSS in Thai which was translated back to English by a bilingual Thai physician preserving original format with seven questions and five-point in Likert’s scale from 0 to 4. First four questions were about urinary urgency, next two items were related to urinary frequency and nocturia, and the last one was to evaluate ability to control their urination. The content validity was evaluated by five Thai expert urologists. Commentaries from subjects and experts were also collected for amendment of the questionnaire. Results: 60 women aged over 18 year old diagnosed overactive bladder by the definition of ICS were recruited and completely studied (mean age 56; SD 17.8). The internal consistency of the questionnaire from both visits were high level of consistency among the seven items answered with Cronbach's alpha coefficient were 0.80 and 0.82 respectively. There was a strong association between the seven-item score of the OABSS-Thai version at visit1 and visit 2 with an intraclass correlation coefficient was 0.96 (95% CI 0.947 to 0.981) Conclusion: A self-completion questionnaires of OABSS in Thai version has proven to be an effective symptom tool for Thai female patient presenting with overactive bladder and easily assess the symptoms and the treatment outcome in overactive bladder.