Cultural and linguistic validation of questionnaires for use in international studies: the nine-item BPH-specific quality-of-life scale.

Questionnaires to evaluate symptoms and quality of life are being increasingly used in urology. It is, however, important that these questionnaires show equivalence when they are used in international, collaborative studies. Precise linguistic and cultural validation should greatly increase their compatibility in different population and cultural groups. Indeed, recent progress in the validation of symptom scores, such as the International Prostate Symptom Score (I-PSS), has helped international comparability in epidemiology and clinical trials. The management of benign prostatic hyperplasia (BPH) increasingly focuses on quality of life and the development of a successful BPH-specific quality-of-life questionnaire is an important advance in the study of BPH. The nine-item BPH-specific quality-of-life scale is currently undergoing linguistic and cultural validation and appears to be satisfactory for extensive use in different cultures.