what us the IIEF-5

The IIEF-5 is a 5-question screening tool that measures erectile dysfunction severity, scored from 5 (severe) to 25 (normal).

The International Index of Erectile Function-5 (IIEF-5) was developed and validated in a 1999 study of 1,152 men, 1,036 of whom had ED [2]. In that study, the average IIEF-5 score among men with ED was 11.1, compared to 23.3 in controls. The tool had 98% sensitivity and 88% specificity at a cutoff score of 21 or below [2].

The five questions cover confidence in getting an erection, ability to penetrate, ability to maintain an erection during intercourse, difficulty maintaining an erection to completion, and overall satisfaction. Scores are categorical: 22-25 is normal, 17-21 mild ED, 12-16 mild-to-moderate, 8-11 moderate, and 5-7 severe [2]. A weighted kappa of 0.82 indicates good agreement of the 5-item version with the full 15-item IIEF diagnostic domain [2].

A 2012 reliability study found that total IIEF scores did not differ significantly between two administrations 1-3 days apart (17.2 vs 17.1, p=0.20), but no patient answered identically on both questionnaires [3]. Answers shifted by only one response option for most patients who changed, so the tool is reliable for tracking big shifts but may miss small changes from a single measurement [3].

The IIEF-5 is also used as a study outcome. In the varicocelectomy study, it captured the shift from severe/moderate ED toward mild/absent ED after surgery [1]. In the CP/CPPS study, 39.9% of 839 men (326) had ED measured by IIEF-5, but ED did not correlate with UPOINT subtype number or NIH-CPSI score [4].

My call: The IIEF-5 is a well-validated, quick screening tool for ED severity that you can complete in about 2 minutes. Score below 21 signals ED. Track changes weekly to see real progress.

Confidence: high. The tool's diagnostic performance was established in a large validation cohort with clear cutoff scores and strong sensitivity/specificity [2].