International Index of Erectile Function – 5 Items (IIEF-5)

Description

The International Index of Erectile Function – 5 Items (IIEF-5), also known as the Sexual Health Inventory for Men (SHIM), is one of the most widely used, scientifically validated self-report instruments for the screening and assessment of erectile dysfunction (ED). Developed by Rosen and colleagues (1999) as a shortened version of the original 15-item International Index of Erectile Function (IIEF), the questionnaire provides a rapid, reliable, and clinically meaningful evaluation of erectile function in both clinical practice and research.

The IIEF-5 consists of five questions that evaluate erectile function over the previous six months. The questionnaire assesses key domains of male sexual function, including confidence in achieving and maintaining an erection, erection firmness sufficient for penetration, maintenance of erection during sexual intercourse, ability to maintain erection until completion of intercourse, and overall satisfaction with sexual intercourse. Each question is answered using a 5-point Likert-type scale, with higher scores indicating better erectile function.

Because of its brevity, excellent psychometric properties, and ease of administration, the IIEF-5 has become the international standard screening instrument for erectile dysfunction. It is extensively used in urology, andrology, sexual medicine, endocrinology, primary care, epidemiological research, and clinical trials evaluating pharmacological, surgical, and psychological interventions for erectile dysfunction.

The IIEF-5 is widely applied in:

  • Urology
  • Andrology
  • Sexual Medicine
  • Endocrinology
  • Men’s Health
  • Primary Care
  • Clinical Psychology
  • Clinical Research and Epidemiology

Assessment with the IIEF-5 enables healthcare professionals to identify the presence and severity of erectile dysfunction, monitor treatment outcomes, evaluate intervention effectiveness, and investigate factors associated with male sexual health and quality of life.

Objective

The primary objective of the IIEF-5 is to provide a reliable and valid assessment of erectile function and to facilitate the early identification and classification of erectile dysfunction.

More specifically, the instrument aims to:

  • Assess confidence in achieving and maintaining an erection.
  • Evaluate erection firmness sufficient for vaginal penetration.
  • Measure the ability to maintain an erection during sexual intercourse.
  • Assess successful completion of sexual intercourse.
  • Evaluate overall satisfaction with sexual performance.
  • Classify the severity of erectile dysfunction.
  • Monitor changes in erectile function over time and following treatment.
  • Support clinical decision-making and scientific research in men’s sexual health.

The IIEF-5 is suitable for adult men in both clinical and community settings and is frequently used as a screening instrument before comprehensive diagnostic evaluation.

Scoring

The IIEF-5 consists of five items, each scored from 1 to 5, with higher scores indicating better erectile function. The total score ranges from 5 to 25 and is calculated by summing the responses to all five questions.

According to the original scoring guidelines:

  • 22–25: No erectile dysfunction
  • 17–21: Mild erectile dysfunction
  • 12–16: Mild-to-moderate erectile dysfunction
  • 8–11: Moderate erectile dysfunction
  • 5–7: Severe erectile dysfunction

Lower scores indicate greater impairment in erectile function and may warrant further medical evaluation. Although the IIEF-5 is an excellent screening instrument, it should be interpreted alongside clinical history, physical examination, laboratory findings, and additional diagnostic assessments when appropriate.

Data Analysis and Applications

Statistical analysis of IIEF-5 data includes descriptive, psychometric, and inferential statistical procedures that evaluate both erectile function and the measurement properties of the questionnaire.

Descriptive Statistics

Initial analyses typically include:

  • Mean
  • Median
  • Standard Deviation
  • Minimum and Maximum values
  • Range
  • Frequencies and Percentages

Reliability Analysis

The psychometric reliability of the IIEF-5 is commonly evaluated using:

  • Cronbach’s Alpha
  • McDonald’s Omega
  • Corrected Item–Total Correlations
  • Split-Half Reliability
  • Test–Retest Reliability

These analyses evaluate the internal consistency and temporal stability of the instrument.

Validity Assessment

Construct validity may be examined through:

  • Exploratory Factor Analysis (EFA)
  • Confirmatory Factor Analysis (CFA)
  • Convergent Validity
  • Discriminant Validity
  • Criterion-related Validity

These procedures verify that the questionnaire accurately measures erectile function and effectively discriminates between different levels of erectile dysfunction.

Group Comparisons

Differences between participant groups may be investigated using:

  • Independent Samples t-test
  • Paired Samples t-test
  • Analysis of Variance (ANOVA)
  • Multivariate Analysis of Variance (MANOVA)
  • Mann–Whitney U Test
  • Kruskal–Wallis Test
  • Analysis of Covariance (ANCOVA)

These analyses facilitate comparisons according to age, comorbidities, treatment groups, cardiovascular risk factors, diabetes status, or other clinical characteristics.

Correlation Analysis

The IIEF-5 is frequently examined in relation to variables such as:

  • Age
  • Testosterone levels
  • Cardiovascular disease
  • Diabetes mellitus
  • Depression
  • Anxiety
  • Quality of life
  • Relationship satisfaction
  • Sexual satisfaction
  • Lifestyle factors

Associations are typically evaluated using Pearson or Spearman correlation coefficients, depending on the characteristics of the data.

Predictive Modeling

Advanced statistical procedures commonly include:

  • Simple Linear Regression
  • Multiple Linear Regression
  • Binary or Ordinal Logistic Regression
  • Structural Equation Modeling (SEM)

These analyses help identify predictors of erectile dysfunction, evaluate treatment outcomes, and investigate the complex relationships between physical health, psychological well-being, and male sexual function.

References

  • Rhoden, E. L., Teloken, C., Sogari, P. R., & Vargas, S. C. (2002). The Use of the Simplified International Index of Erectile Function (IIEF-5) as a Diagnostic Tool to Study the Prevalence of Erectile Dysfunction. International Journal of Impotence Research, 14, 245–250.
  • Rosen, R. C., Cappelleri, J. C., Smith, M. D., Lipsky, J., & Peña, B. M. (1999). Development and Evaluation of an Abridged, 5-Item Version of the International Index of Erectile Function (IIEF-5) as a Diagnostic Tool for Erectile Dysfunction. International Journal of Impotence Research, 11(6), 319–326.
  • Rosen, R. C., Riley, A., Wagner, G., Osterloh, I. H., Kirkpatrick, J., & Mishra, A. (1997). The International Index of Erectile Function (IIEF): A Multidimensional Scale for Assessment of Erectile Dysfunction. Urology, 49, 822–830.
  • Rosen, R. C., Althof, S. E., & Giuliano, F. (2006). Research Instruments for the Diagnosis and Treatment of Patients with Erectile Dysfunction. Urology, 68, 6–16.