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

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.

This was a retrospective study. Three hundred thirty-one patients who underwent radical prostatectomy at Beijing Hospital 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 4 severity levels defined according to guidelines. Bootstrap estimated the differences in Kappa coefficients. Trends in severity and recovery time across grades were evaluated.

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 <.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 <.001). This system corresponded to the patients' recovery trend; there was an association between early severity grade and subsequent recovery.

Compared with existing assessment tools, 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.