Prevalence of Discordance Between Patient- and Physician-Reported Questionnaire in Japanese Male: Insight From a Prospective Observational Study Using the International Prostate Symptom Score.

Objectives: This study aimed to prospectively clarify the prevalence of discordance between patient- and physician-reported International Prostate Symptom Score in Japanese males and evaluate the factors affecting the discordant response of the questionnaire.

Methods: From May 2022 to December 2023, a prospective single-institutional observational study was conducted. A total of 310 male patients with lower urinary tract symptoms were prospectively registered to the study. The International Prostate Symptom Score questionnaire was first completed by patients and then filled out by physicians during the patient interview. We compared the self-reported score with the physician-reported score to assess the accuracy of self-reporting by three age groups. Agreement of symptom score was assessed using the weighted kappa coefficient. Multivariable logistic regression analysis was performed to identify the associated factors with discordant responses.

Results: A total of 281 patients were included in the final analysis. Of these, 51.7% of patients were able to concordantly self-report all seven questions of IPSS. The number of questions and patients with discordant responses in the questionnaire significantly increased with age. The most frequently discordant questions were weak stream (19.5%). The weighted kappa value between patient and physician was 0.82. Multivariable analysis showed that older age, higher International Prostate Symptom Score, and inappropriate registration forms were associated with discordant responses.

Conclusions: A nearly half of male outpatients gave discordant results of the International Prostate Symptom Score questionnaire in our cohort. Given our finding, caution may be warranted when interpreting IPSS in elderly men with moderate to severe symptoms or accompanying inappropriate registration form.