The DAN-PSS-1 system, a self-administered quality-of-life questionnaire comprising 12 questions related to voiding problems and the perceived bother of each individual symptom, was compared to other extensively used score systems and furthermore included in different clinical situations so as to validate the system. The system was internally consistent (alpha cr = 0.73), the median test-retest reliability of answers to each question was 83.5% (range 0-99.7%). A high degree of construct validity demonstrated in the correlation with the Madsen-Iversen score system (rs = 0.51) and with the patients' answers to questions about how bothersome their symptoms were (rs = 0.71). The discriminant validity of the DAN-PSS-1 was excellent with an area under the ROC curve of 0.94. Finally, the DAN-PSS-1 was sensitive to changes following intervention, with scores decreasing 100% after transurethral prostatectomy and 65% after four months of treatment with an alpha-blocker. The DAN-PSS-1 is reliable, valid and responsive, and therefore can be recommended for assessing the severity of symptoms among patients presenting with lower urinary tract complaints suggestive of BPH and during follow-up.