• Erectile Dysfunction;
  • Penile Duplex;
  • Nocturnal Penile Tumescence


Introduction.  Currently there is no universally accepted gold standard diagnostic test to differentiate psychogenic from physical erectile dysfunction (ED). Instead, sexual health specialists rely on a detailed history, a focused physical examination, and specialized diagnostic tests, to decide if the etiology of the ED is mainly psychogenic or organically caused.

Aim.  In this review we point out the status of evidence-based principles in the area of diagnosis in Sexual Medicine.

Methods.  We review the concepts of evidence-based medicine (EBM) in the area of medical diagnostic tests. We highlight four of the well-known diagnostic tests (penile duplex, pharmacoarteriography, pharmacocavernosometry/cavernosography [PHCAS/PHCAG], and nocturnal penile tumescence [NPT monitoring]) for ED evaluation within an evidence-based perspective.

Main Outcome Measures.  Assessment of diagnostic tests for ED using principles of EBM.

Results.  Several good diagnostic tests are useful in the evaluation of men with ED. However, modern evidence-based concepts—mainly the likelihood ratio—have not yet been applied to these tests to obtain their maximum clinical benefits.

Conclusions.  While penile duplex/color Doppler has good evidence of supporting its use in the diagnosis of arteriogenic ED, data supporting its diagnosis of a physical disorder associated with cavernous venous occlusion dysfunction are lacking. PHCAS/PHCAG's main drawback is an unknown positive predictive value and a possibility of frequent false-positive results. NPT has many advantages when differentiating psychogenic from organic ED, however, several questions related to its physiological mechanisms do exist. Ghanem H, and Shamloul R. An evidence-based perspective to commonly performed erectile dysfunction investigations. J Sex Med 2008;5:1582–1589.

[Correction added after online publication 14-Dec-2007: In the above reference for this article, the order of the author names has been updated.]