THE INTERNATIONAL INDEX OF ERECTILE FUNCTION (IIEF) - A MULTIDIMENSIONAL SCALE FOR ASSESSMENT OF ERECTILE DYSFUNCTION

Objectives. To develop a brief, reliable, self-administered measure of erectile function that is cross-culturally valid and psychometrically sound, with the sensitivity and specificity for detecting treatment-r elated changes in patients with erectile dysfunction. Methods. Relevan t domains of sexual function across various cultures were identified v ia a literature search of existing questionnaires and interviews of ma le patients with erectile dysfunction and of their partners. An initia l questionnaire was administered to patients with erectile dysfunction , with results reviewed by an international panel of experts. Followin g linguistic validation in 10 languages, the final 15-item questionnai re, the International Index of Erectile Function (IIEF), was examined for sensitivity, specificity, reliability (internal consistency and te st-retest repeatability), and construct (concurrent, convergent, and d iscriminant) validity. Results. A principal components analysis identi fied five factors (that is, erectile function, orgasmic function, sexu al desire, intercourse satisfaction, and overall satisfaction) with ei genvalues greater than 1.0. A high degree of internal consistency was observed for each of the five domains and for the total scale (Cronbac h's alpha values of 0.73 and higher and 0.91 and higher, respectively) in the populations studied. Test-retest repeatability correlation coe fficients for the five domain scores were highly significant. The IIEF demonstrated adequate construct validity, and all five domains showed a high degree of sensitivity and specificity to the effects of treatm ent. Significant (P values = 0.0001) changes between baseline and post -treatment scores were observed across all five domains in the treatme nt responder cohort, but not in the treatment nonresponder cohort. Con clusions. The IIEF addresses the relevant domains of male sexual funct ion (that is, erectile function, orgasmic function, sexual desire, int ercourse satisfaction, and overall satisfaction), is psychometrically sound, and has been linguistically validated in 10 languages. This que stionnaire is readily self-administered in research or clinical set; t ings. The IIEF demonstrates the sensitivity and specificity for detect ing treatment-related changes in patients with erectile dysfunction. ( C) 1997, Elsevier Science Inc. All rights reserved.