Patient-reported outcome measures (PROMs) used to assess sexual functioning in prostate cancer patients: A systematic review of psychometric properties

Background: Prostate cancer (PCa) significantly impacts patients' sexual functioning and quality of life. Patient-reported outcome measures (PROMs) are essential for accurately assessing these issues, yet a comprehensive evaluation of their psychometric properties in PCa patients is lacking. Aims: This systematic review aimed to provide a comprehensive evaluation of all generic and specific PROMs used to assess sexual functioning in PCa patients and make recommendations the application of PROMs in this patient group. Methods: Six electronic databases were searched from up to May 5, 2024. Studies reporting the development and/or validation of PROMs for PCa patients or generic instruments administered to this population were included. The COSMIN risk of bias checklist was adopted to assess the methodological quality and psychometric properties of included PROMs. Psychometric properties of the PROM in each included study were rated against the criteria for good measurement properties based on the COSMIN guideline. Outcomes: The main outcome was to identify the appropriate PROM that can be adopted and used for assessing sexual functioning in PCa patients in clinical setting. Results: A total of 10 PROMs were identified across 32 studies, primarily focusing on localized PCa patients after radical prostatectomy. The Expanded Prostate Cancer Index Composite (EPIC-26) was the most frequently evaluated and widely used PROM in clinical practice. EPIC-26 (Spanish, Italian, Chinese versions) and UCLA Prostate Cancer Index (UCLA-PCI) demonstrated better psychometric properties compared to other scales. However, no PROM met all COSMIN standards. Clinical Implications: In a clinical setting, it is crucial to utilize well-validated PROMs with good psychometric properties to effectively identify patients with PCa experiencing sexual difficulties who may require additional support. Strengths and Limitations: We applied strict inclusion criteria related to study design and study population, ensuring the assumption of transitivity and the consistency of the analysis. Conclusion: Although EPIC-26 is a shortened version with strong psychometric properties, it may still be too lengthy for patients with significant health issues. Furthermore, the included PROMs do not address issues related to partner relationships, or the psychological impact of sexual dysfunction in sufficient detail. Future research should aim to develop and validate new PROMs that fill these gaps. These tools should be both psychometrically robust and practical for routine use, enabling real-time monitoring and improved care delivery.