Validation of the International Prostate Symptom Score in Chinese males and females with lower urinary tract symptoms

OBJECTIVES: To evaluate the translation of the IPSS (Hong Kong Chinese version 1) and to assess the applicability, validity, reliability and sensitivity of the instrument in both males and females with LUTS in Chinese population. METHODS: The translation of the IPSS (Hong Kong Chinese version 1) was reviewed through back translation. Modifications were made, resulting in the development of The IPSS (Hong Kong Chinese version 2). The content validity was assessed by contend validity index. 233 subjects with LUTS were recruited in Hong Kong primary care settings for pilot psychometric testing. The construct validity was assessed by corrected item-total correlation and Pearson’s correlation test against ICIQ-UI SF, IIQ-7 and SF-12 v2. The reliability was assessed by the internal consistency (Cronbach’s Alpha coefficient) and test –retest reliability (Intraclass correlation coefficient). The Sensitivity was determined by performing known group comparisons by independent T-test. RESULTS: The content validity index for all items could reach 1. Corrected item-total correlation scores were ≥0.4 for four symptom questions (feeling of incomplete bladder emptying, intermittency, weak stream and straining). Overall, the total symptom score moderately correlated with ICIQ-UI SF. The quality of life score moderately correlated with the IIQ-7 but weakly correlated with SF-12 v2. Overall, the reliability of the IPSS (Hong Kong Chinese version 2) was acceptable (Cronbach’s Alpha coefficient = 0.71, ICC of the symptom questions =0.8, ICC of the quality of life question =0.7). The symptoms questions and quality of life questions of the IPSS (Hong Kong Chinese versions 2) were sensitive in detecting differences between groups. CONCLUSIONS: The IPSS (Hong Kong Chinese version 2) is a valid, reliable and sensitive measure to assess Chinese females and males with lower urinary tract symptoms. The IPSS quality of life question is more sensitive than the generic quality of life measure to differentiate subgroups.