The incontinence impact questionnaire-7 (IIQ-7) can be applicable to Chinese males and females with lower urinary tract symptoms.

Abstract

The aim of this study was to extend the scope of application of the Incontinence Impact Questionnaire-7 (IIQ-7) with the objective of assessing the applicability, validity, reliability and sensitivity of the IIQ-7 in both Chinese males and females with lower urinary tract symptoms (LUTS). The validity, reliability and sensitivity were assessed in 233 patients who were recruited in Hong Kong primary-care settings. The internal construct validity was assessed by corrected item-total correlation. The convergent validity was assessed using Pearson's correlation test against International Prostate Symptom Score (IPSS) quality-of-life question and Short Form 12, version 2 (SF-12v2). The reliability was assessed by the internal consistency (Cronbach's alpha coefficient) and 2-week test-retest reliability (intraclass correlation coefficient and paired t test). The sensitivity was determined by performing known group comparisons by independent t test. Corrected item-total correlations were ≥0.4 for all items in males and females. Overall, the IIQ-7 total score had a stronger correlation with IPSS quality-of-life score than the SF-12v2. The IIQ-7 showed good internal consistency (Cronbach's alpha coefficient >0.7) and good test-retest reliability (ICC>0.8, paired t test p value >0.05). The IIQ-7 was more sensitive than the SF-12v2 to detect differences among patients with different levels of symptom severity. The IIQ-7 Chinese version appears to be a valid and reliable measure to assess Cantonese-speaking males and females with LUTS. The IIQ-7 is more sensitive than generic health-related quality-of-life measures to detect differences between groups.