Introduction: The validated Quality of Erection Questionnaire (QEQ) is a six-question, patient-reported outcome measure for comprehensively evaluating satisfaction with the quality of erections in terms of hardness, onset, and duration, which can be used to develop and monitor individualized treatment goals.
Aims: To further validate the QEQ by determining responsiveness/sensitivity to change in erectile function, erection hardness grade, and psychosocial outcomes in men treated with sildenafil for erectile dysfunction (ED).
Methods: This open-label, noncomparative, multicenter trial of sildenafil (50 or 100 mg as needed for 10 weeks) enrolled men with ED who were in a stable, sexual relationship for at least 6 months. Previous phosphodiesterase type 5 inhibitor use must have been no more than 6 doses ever and no doses more recently than the previous 4 weeks.
Main outcome measures: The baseline to week 10 change in the QEQ total score and its correlations with the end-of-treatment Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS) score and with changes in: (i) International Index of Erectile Function (IIEF) domain scores; (ii) Self-Esteem And Relationship (SEAR) questionnaire component scores; and (iii) the frequency of erections graded hard enough for penetration (grade 3) or completely hard (grade 4) on the event log Erectile Hardness Grading Scale.
Results: The mean +/- standard deviation transformed QEQ total score tripled from 22.0 +/- 21.1 to 69.9 +/- 35.9 (P < 0.0001), and correlated positively with the end-of-treatment EDITS index score (r = 0.71) and with changes in IIEF domain scores (r = 0.29-0.86), SEAR component scores (r = 0.37-0.78), and the percentage of occasions that grade 3 or 4 erections were achieved (r = 0.66).
Conclusions: The brief, easy-to-administer QEQ is responsive to the benefits of sildenafil treatment of men for ED and has convergent validity with measures of clinical and psychosocial outcomes.