1997 Volume 24 Issue 1 Pages 75-86
A comprehensive investigation of sexual fuctions in aged persons, covering more than 10, 000 subjects, was made by Kumamoto and his colleagues (1992). We have tried to construct a single index for evaluating sexual function from part of their original data. Twelve questions concerning psychological and physical aspects of sexual activity were selected from the multiphasic questionnaire used by Kumamoto's group. Each question was answered as a numeric grade ranging from 0 to 5. A principal component analysis was carried out. The eigenvalues, the eigenvectors of the 10 principal components, and the principal component scores of 3, 677 subjects were all calculated. Since the signs of the first eigenvectors were positive for all 10 items, we proposed that they represented intensity of sexual function, an “S-score”. For ease of use, we simplified this S-score to Sum-score (simple sum of the response of each question) and further developed a nomogram to show the sexual function of each subject on the Sum-score vs age plane. Although the Sum-score used only about half of the information originally contained in the answers, we concluded that this simple presentation of complex sexual functions would likely have considerable merit in evaluating patients in clinical practice.
