Related Experiment Video
Updated: May 10, 2026

Treatment Model for Young Patients with Psychogenic Erectile Dysfunction and Resultant Infertility
Published on: May 30, 2025
Enhanced understanding of the relationship between erection and satisfaction in ED treatment: application of a
A G Bushmakin1, J C Cappelleri1, T Symonds2
1Pfizer, Statistics, Groton, CT, USA.
Abstract:
To apportion the direct effect and the indirect effect (through erections) that sildenafil (vs placebo) has on individual satisfaction and couple satisfaction over time, longitudinal mediation modeling was applied to outcomes on the Sexual Experience Questionnaire. The model included data from weeks 4 and 10 (double-blind phase) and week 16 (open-label phase) of a controlled study. Data from 167 patients with erectile dysfunction (ED) were available for analysis. Estimation of statistical significance was based on bootstrap simulations, which allowed inferences at and between time points. Percentages (and corresponding 95% confidence intervals) for direct and indirect effects of treatment were calculated using the model. For the individual satisfaction and couple satisfaction domains, direct treatment effects were negligible (not statistically significant) whereas indirect treatment effects via the erection domain represented >90% of the treatment effects (statistically significant). Week 4 vs week 10 percentages of direct and indirect effects were not statistically different, indicating that the mediation effects are longitudinally invariant. As there was no placebo arm in the open-label phase, mediation effects at week 16 were not estimable. In conclusion, erection has a crucial role as a mediator in restoring individual satisfaction and couple satisfaction in men with ED treated with sildenafil.
Related Concept Videos
Self-Evaluation Maintenance Model
Male Sexual Response: Erection & Ejaculation
The blood filling the erectile tissues compresses the veins, which helps to prevent blood from leaving...
Self-Discrepancy Theory
Modeling in Therapy
Participant Modeling
Participant modeling involves therapists demonstrating calm and effective behaviors in situations...
Pharmacodynamic Models: Linear Concentration–Effect Model
Longitudinal Research