Purpose: With the changing age structure of the population in the Western industrial nations, age-correlated illnesses like erectile dysfunction are becoming increasingly important. At this time no questionnaire is available that has been validated in the German language and with German-speaking patients. Hence, we developed and validated a questionnaire (Cologne assessment of erectile dysfunction "KEED") with patients of the Department of Urology, University of Cologne. The questionnaire was developed to register symptoms of erectile dysfunction. Material and Methods: It was given to 125 patients who where transferred to our outpatient clinic between November 1997 to February 1998. The men were examined in accordance with their specific symptoms. In this way clinical diagnosis was matched with the subjective patient information. Calculation of an E.D.-Score was made possible by the specific design of the questionnaire. Sensitivity, specifictiy and positive predictive value of the total sum values were computed. The average age of the patients was 56.3 years. Results: 105 of the 125 patients (85%) answered the questions completely and correctly. With the sum values of the E.D.-Score, an ideal cut-off value of 17 with a sensitivity of 0.97, specificity of 0.93 and a positive predictive value of 0.98 was computed. The answer about contentment with sexual intercourse showed a positive correlation from 0.74. Conclusions: The "Cologne assessment of erectile dysfunction" (KEED) is the first in German and with German-speaking patients validated questionnaire. It offers the possibility of exact monitoring the symptoms of erectile dysfunction. Consequently, it represents a suitable instrument for epidemiological investigations in German-speaking populations. For clinical use "KEED" offers, by the separate assessment of erectile function and impairment of quality of life, the possitbility of a better judgement of the therapy necessity and success.
