Validation of the Patient Global Impression of Improvement (PGI-I) for Penile Prosthesis

As outlined above, we aim to use and validate the patient global impression of improvement questionnaire (PGI-I) (appendix 1) to evaluate patient improvement and satisfaction following placement of a penile prosthesis. The study is designed as a dual institutional study and validation of the PGI-I will be through a prospective longitudinal observation method. Patients who elect to have IPP implantation will be offered participation in this study. All patients will be thoroughly explained the nature and purpose of the study, and written informed consent will be obtained prior to study participation. The Northwestern Memorial Hospital and Ochsner Clinic/ Ochsner Clinic Foundation institutional review boards have granted approval for the initiation of this study. Pre-operatively, all patients will also complete the International Index of Erectile Function (IIEF) (appendix 2) and the Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS) (appendix 3) questionnaires. The IIEF is a widely used, multi-dimensional self-reported instrument for the evaluation of male sexual function. Patient responses to various treatments for ED are routinely measured with IIEF, and it has been extensively utilized in various clinical trials. The IIEF was developed in conjunction with the clinical trial program for sildenafil, and has been adopted as the “gold standard” measure for efficacy assessment in clinical trials of ED. Moreover, the IIEF meets psychometric criteria for test reliability and validity, has a high degree of sensitivity and specificity, and correlates well with other measures of treatment outcome. It has demonstrated consistent and robust treatment responsiveness in studies in the US, Europe, and Asia, as well as in a wide range of etiological subgroups. Additionally, the EDITS questionnaire is another validated instrument, which was initially developed to assess patient satisfaction to various ED therapies and explore the impact of patient and partner satisfaction on treatment continuation. Previous studies have documented use of EDITS to evaluate the ED patient satisfaction’s to therapies such as sildenafil, intracavernosal injections, and penile prosthesis. Both the IIEF and EDITS questionnaires have even been used together to measure patient improvement and satisfaction with IPP surgery with sustainable accuracy. 4 Preoperative IIEF and EDITS will be obtained on every patient and analyzed. ED severity will be characterized based on IIEF erectile function domain scores as follows: severe – less than 10, moderate - 11 to 17, mild – 18 to 25, and none – greater than 25. EDITS scores were based on 100 points: 0 – least satisfied to 100 – most satisfied. Clinical parameters such as mean age of the patient, duration of ED, patient comorbidities, smoking history, and surgical history will also be examined. Study exclusion criteria include repeat implant surgery, prosthesis infection, and nonfunctioning IPPs. The patient will have standard post-operative care, which includes a routine visit at 4-6 week for wound evaluation and prosthesis activation and training. Future visits will be at 3, 6, and 12-month intervals, during which the patient will fill out an IIEF, EDITS, and a PGI-I for the penile prosthesis (Table 1). The objective of this study is to examine the accuracy of the PGI-I in measuring patient satisfaction following IPP implantation. Patient responses to the PGI-I will be compared to the pre and post-operative IIEF and EDITS scores. The student t-test will be used to compare pre-operative data to post-operative d