Convergent Validity of Stamey's Incontinence Scoring System in Assessing Post-Prostatectomy Urinary Incontinence.

OBJECTIVE: To investigate the convergent validity of Stamey's Incontinence Scoring System, a simple tool, in assessing post-prostatectomy incontinence at different time points after surgery. METHODS: This was a retrospective study. 331 patients who underwent radical prostatectomy from January 2024 to May 2025 took part; 295 completed the study. Data of Stamey's Grade, ICI-Q-SF, and daily pad use at 1.5, 3, 6, and 12 months postoperatively were recorded. Spearman's rank correlation assessed the correlation between Stamey's grade and ICI-Q-SF. Quadratic weighted Kappa compared daily pad use and Stamey's grade for their agreement with ICI-Q-SF, with four severity levels defined according to guidelines. Bootstrap estimated differences in Kappa coefficients. Trends in severity and recovery time across grades were evaluated. RESULTS: Across 735 data records at different time points, this system showed strong positive correlations with ICI-Q-SF (correlation coefficients = 0.699, 0.752, 0.920, 0.947; all P<0.001). Bootstrap comparisons showed that the agreement of Stamey's Scoring System with ICI-Q-SF (Kappa = 0.445, 0.486, 0.747, 0.659) was significantly higher than that of daily pad use (Kappa = 0.054, 0.017, 0.188, 0.214) at all postoperative time points (P<0.001). This system corresponded to the patients' recovery trend; There was an association between early severity grade and subsequent recovery. CONCLUSIONS: Compared with existing assessment tools, the Stamey's grade has a simpler questionnaire structure and higher consistency. This can make follow-up for patients after radical prostatectomy more efficient and reduce clinical workload.