Some Developments on the International Index of Erectile Function (IIEF)

Abstract

This manuscript covers two complementary topics. For both topics, data from clinical studies and control samples were used. The first topic provides an overview of the development and validation of the International Index of Erectile Function (IIEF), a 15item questionnaire, for male erectile and sexual function. A principal components analysis revealed five factors (erectile function, orgasmic function, sexual desire, intercourse satisfaction, and overall satisfaction). The IIEF demonstrated reliability, validity, and sensitivity and specificity with regard to treatment effect. The second topic presents, among men who reported having had sexual intercourse, the methodology and results on the evaluation of the erectile function (EF) domain of the IIEF; which has a range of scores from 6-30 for these men, as a diagnostic tool to help discriminate between men with and without erectile dysfunction (ED). For a prevalence rate of ED equal to 0.5 in a clinical population, the Classification and Regression Trees program gave a cutoff score of 25: men with EF scores of 25 or less were retrospectively classified as having ED, while those with scores above 25 were classified as not having ED (sensitivity = 0.97, specificity = 0.88). The IIEF has been developed and validated as a scale that is

Erectile dysfunction in a primary care setting: results of an observational, no-control-group, prospective study with sildenafil under routine conditions of use

“…This questionnaire is a simple (15 items), reliable, multidimensional, self-administered tool which has shown its linguistic and psychometric validity for examining erectile function in different languages, including Spanish. 12,13,18 The questionnaire explores five dimensions of the sexual sphere: erectile function, orgasmic function, sexual desire, satisfaction with intercourse and overall satisfaction with sexual activity.…”

“…11 For this purpose, the IIED is a reliable measure of erectile function whose cross-cultural validity has been shown, and which has adequate sensitivity and specificity to detect changes related to the treatment in patients with ED. 12,13 However, the impact of ED treatment is not restricted exclusively to the achievement of an erectile response, but will reasonably often be transferred to other areas of life of the ED patient. Thus, some studies show a significant correlation between ED and quality of life.…”

The International Index of Erectile Function (IIEF): a state-of-the-science review

“…9,10 These included standard psychometric tests of reliability, validity, and sensitivity (treatment responsiveness). Two aspects of scale reliability -internal consistency and testretest -were separately examined for the five domains and for the total scale.…”

“…9 Accordingly, the ability of the EF domain to serve as a diagnostic tool to discriminate between men with and without ED, as well as to classify the degree of severity of the disorder, was investigated. 10,52 For this analysis, baseline patient data from four separate sildenafil trials were pooled for comparison with an age-matched control sample. A total of 1035 patients and 116 controls from the USA and UK were included in the analysis.…”

Quality of Sexual Life Questionnaire (QVS): a reliable, sensitive and reproducible instrument to assess quality of life in subjects with erectile dysfunction

“…As regards IIEF, all the scores were lower in ED subjects than in subjects without ED, confirming the presence of ED. 29 The operational QVS version was analysed using the data of 284 subjects with ED (samples 1 and 3) and having completed the questionnaire without missing data. Results are summarised in Table 2.…”