Validation of an Abridged Korean Version of the International Index of Erectile Function (IIEF-5) as a Diagnostic Tool for Erectile Dysfunction

Ahn, Tai Young; Lee, Dong Soo; Kang, Wee chang; Hong, Jun Hyuk; Kim, Young Sik

Abstract

PURPOSE: An abridged 5-item version of the 15-item International Index of Erectile Function (IIEF) was developed and its validity has been proven in the western medical community. This study was designed to assess the validity of the abbreviated Korean version of the IIEF as a diagnostic tool for ED.
MATERIALS AND METHODS
Patients who visited the Andrology Clinic of the Asan Medical Center with a chief complaint of ED fall into the patient group. Patients who visited the Family Medicine Clinic of the same hospital with chief complaints other than ED, and checked no ED in the self-assessment questionnaire, fall into the control group. Patients, both of the patient group and control group, were asked to fill out the self-administered IIEF-5 and the questionnaire asking the severity of the ED.
RESULTS
Collected questionnaires from a total of 309 subjects (the patient group: 149; the control group: 160) were used for statistical analysis. Mean ages were 43 and 52 for the control group and the patient group, respectively. A Receiver Operating Characteristics (ROC) Curve analysis indicated that there is a close correlation between IIEF-5 total scores and the presence of ED (area under the ROC curve=0.961). The most appropriate cutoff score between ED and no ED was 17 (sensitivity=91.3%, specificity=86.3%). Substantial consistency existed between the predicted and the patient-answered ED severity levels (Weighted Kappa=0.681).
CONCLUSIONS
The Korean version of IIEF-5 is highly effective in detecting the presence and assessing the severity of ED. The result of our study supports its validity as a diagnostic instrument in the clinical setting.