The self-estimation index of erectile function-no sexual intercourse (SIEF-NS): a multidimensional scale to assess erectile dysfunction in the absence of sexual intercourse.

ABSTRACT

INTRODUCTION: A new concept of Erectile Dysfunction with No Sexual Intercourse (ED-NS) is proposed to acknowledge the subpopulation of patients who are unable to achieve or sustain an erection in the absence of sexual intercourse. Since the commonly used ED diagnostic tool, International Index of Erectile Function Questionnaire is not able to adequately assess the erectile function (EF) in the absence of intercourse, the researchers developed a new 10-item questionnaire to better evaluate the EF in this special patient subpopulation Self-Estimation Index of Erectile Function-No Sexual Intercourse (SIEF-NS). AIM: To validate the reliability, sensitivity and specificity of SIEF-NS. METHODS: The study was carried out in three phases. Phase one applied component analysis to 126 ED-NS patients to search for the primary factors and Cronbach's alpha standardized statistic values for SIEF-NS. Phase two applied discriminant analysis to participants' (212 ED-NS patients and 193 normal controls) scores on each question item, each factor and the overall 10-item questionnaire. Phase three investigated SIEF-NS's capability of evaluating treatment effect on 41 ED-NS patients. MAIN OUTCOME MEASURES: Reliability, sensitivity and specificity were defined and used to evaluate the performance of SIEF-NS. RESULTS: EF by autonomic response (factor 1) and EF with potential sexual partners (factor 2) are the two primary factors with eigenvalues greater than 1.0. High degree of internal consistency was observed for the two factors and the 10-item questionnaire (Cronbach's alpha values 0.871 for 10 items, 0.84 for factor 1, and 0.823 for factor 2). SIEF-NS demonstrated adequate construct validity, high sensitivity (0.925) and specificity (0.829) to diagnose ED-NS. The EF scores of ED-NS patients post treatment showed significant improvement (P < 0.05). CONCLUSION: SIEF-NS can be used to identify ED-NS patients and detect treatment-related EF changes in ED-NS patients.