Validation of the erection hardness score.
BACKGROUND
Erection hardness is a fundamental component of erectile function, and is a very specific and easily monitored outcome. The Erection Hardness Score (EHS) is a single-item, patient-reported outcome (PRO) for scoring erection hardness.


OBJECTIVE
The aim of this article is to report the psychometric validation of the EHS.


METHODS
The dataset (N = 307) was from a multinational sildenafil trial (efficacy in the treatment of erectile dysfunction [ED]) with a 2-week screening phase, a 6-week double-blind, placebo-controlled treatment phase, and a 6-week open-label extension.


METHODS
Test-retest reliability (intraclass correlation coefficient), quality and distribution of responses, known-groups validity (ability to differentiate between ED severity groups defined by the International Index of Erectile Function [IIEF] questionnaire), convergent validity (Pearson correlation coefficients with domain scores of the IIEF and the Quality of Erection Questionnaire [QEQ]), treatment responsiveness, and clinically important difference.


RESULTS
The EHS demonstrated good test-retest reliability, acceptable quality and distribution of responses, known-groups validity against the IIEF (including clear differentiation between normal and impaired erectile function), moderate-to-strong convergent validity against the prespecified domains of the IIEF and QEQ, and high treatment responsiveness.


CONCLUSIONS
The EHS has desirable measurement properties, including being highly responsive to treatment. This one-item PRO is robust and easy to use for evaluating erection hardness. Psychometric analysis supports the use of the EHS as a simple, reliable, and valid tool for the assessment of erection hardness in clinical trials research.
Mulhall
John P
JP
Weill Medical College of Cornell University and Memorial Sloan Kettering Cancer Center, New York, NY 10021, USA. jpm2005@med.cornell.edu
Goldstein
Irwin
I
Bushmakin
Andrew G
AG
Cappelleri
Joseph C
JC
Hvidsten
Kyle
K
D000328:Adult; D007172:Erectile Dysfunction / Q000175:diagnosis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010410:Penile Erection; D011594:Psychometrics; D011788:Quality of Life; D015203:Reproducibility of Results; D012107:Research Design; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D012725:Sexual Behavior; D020018:Sexual Dysfunctions, Psychological / Q000175:diagnosis*; D011795:Surveys and Questionnaires