PURPOSE: To validate the Quality of Erection Questionnaire (QEQ) considering Brazilian social-cultural aspects.
MATERIALS AND METHODS: To determine equivalence between the Portuguese and the English QEQ versions, the Portuguese version was back-translated by two professors who are native English speakers. After language equivalence had been determined, urologists considered the QEQ Portuguese version suitable. Men with self-reported erectile dysfunction (ED) and infertile men who had a stable sexual relationship for at least 6 months were invited to answer the QEQ, the International Index of Erectile Function (IIEF) and the RAND 36-Item Health Survey (RAND-36). The questionnaires were presented together and answered without help in a private room. Internal consistency (Cronbach's α), test-retest reliability (Spearman), convergent validity (Spearman correlation) coefficients and known-groups validity (the ability of the QEQ Portuguese version to differentiate erectile dysfunction severity groups) were assessed.
RESULTS: We recruited 197 men (167 ED patients and 30 non-ED patients), mean age of 53.3 and median of 55.5 years (23-82 years). The Portuguese version of the QEQ had high internal consistency (Cronbach α=0.93), high stability between test and retest (ICC 0.83, with IC 95%: 0.76-0.88, p< 0.001) and Spearman correlation coefficient r=0.82 (p< 0.001), which demonstrated the high correlation between the QEQ and IIEF results. The correlations between the QEQ and RAND-36 were significantly low in ED (r=0.20, p=0.01) and non-ED patients (r=0.37, p=0.04).
CONCLUSION: The QEQ Portuguese version presented good psychometric properties and high convergent validity in relation to IIEF. The low correlations between the QEQ and the RAND-36, as well as between the IIEF and the RAND-36 indicated IIEF and QEQ specificity, which may have resulted from the patients' psychological adaptations that minimized the impact of ED on Quality of Life (QoL) and reestablished the well-being feeling.
Written by:
Reis AL, Reis LO, Saade RD, Santos CA Jr, Lima ML, Fregonesi A. Are you the author?
Department of Surgery (Urology), Faculty of Medical Sciences, University of Campinas (Unicamp), Brazil; Medicine (Urology), Center for Life Sciences, Pontifical Catholic University of Campinas (PUCCampinas), Brazil.
Reference: Int Braz J Urol. 2015 Jan-Feb;41(1):155-67.
doi: 10.1590/S1677-5538.IBJU.2015.01.21
PubMed Abstract
PMID: 25928522