Depression, Illness Perception, and Erectile Dysfunction Outcomes

This prospective, observational study aims to investigate the relationship between illness perception and depressive symptoms in patients diagnosed with erectile dysfunction (ED), and how these factors influence treatment response over time. Erectile dysfunction is a multifactorial condition that significantly affects quality of life and can be shaped by psychological and cognitive factors, including patients' perceptions of their disease.

A total of 120 adult male participants (aged \>18 years) diagnosed with ED will be enrolled from multiple urology centers. Patients will complete three validated instruments at baseline and again at a 1-month follow-up:

IIEF-5 (International Index of Erectile Function - 5): to assess severity of erectile dysfunction.

B-IPQ (Brief Illness Perception Questionnaire): to evaluate cognitive and emotional representations of their condition.

PHQ-9 (Patient Health Questionnaire - 9): to screen for and quantify depressive symptoms.

The primary outcome of the study is to determine the association between baseline illness perception (as measured by B-IPQ) and the severity of depressive symptoms (PHQ-9 scores). Secondary outcomes include changes in erectile function (IIEF-5) and depressive symptoms at 1 month, and whether these changes correlate with changes in illness perception. Additionally, specific components of illness perception such as personal control, treatment control, concern, and emotional response will be analyzed in relation to treatment adherence and psychological well-being.

Data Quality and Management Procedures:

A structured case report form (CRF) will be used for consistent data entry. A data dictionary will define each variable and ensure uniform interpretation of collected data.

Data checks will be performed to validate internal consistency (e.g., checking for missing or out-of-range values).

Source data verification will involve comparison of collected responses with patients' medical records when applicable.

Standard Operating Procedures (SOPs) will be followed for data collection, participant follow-up, and data management.

Sample Size and Statistical Plan:

A power analysis indicated a required sample size of 120 participants to detect a moderate correlation (r = 0.3) between illness perception and depressive symptoms with 80% power and a 5% significance level.

Statistical analysis will include:

Descriptive statistics for demographic and clinical variables. Pearson or Spearman correlation analysis between B-IPQ, PHQ-9, and IIEF-5 scores.

Paired t-tests or Wilcoxon signed-rank tests to assess within-group changes over time.

Multivariate regression analysis to control for potential confounders such as age, comorbidities, and duration of ED.

Missing Data Plan:

Cases with missing responses will be addressed using multiple imputation methods where appropriate. Sensitivity analyses will be conducted to assess the impact of missing data on study outcomes.

This study will provide insight into how modifiable psychological factors such as illness beliefs influence both psychological distress and sexual health, potentially informing future patient education and intervention strategies.