Enhanced interpretability of the PFDI-20 with establishment of reference scores among women in the general population

Aims To enhance the interpretability of the PFDI-20 by establishing a score distribution for women in the general population and to determine whether scores correspond with urinary and anal incontinence (UI and AI). Methods Subjects recruited during Twins Day Festivals from 2004 to 2009 completed a survey assessing for stress and urgency urinary incontinence (SUI and UUI) and AI of flatus and stool. Score distributions for the PFDI-20 and each of its subscales were determined for all subjects and for women with isolated forms of incontinence. Scores were compared between continent and incontinent women and between incontinent subtypes by Wilcoxon rank-sum tests. Results One thousand three hundred seventy-six women completed the survey with PFDI-20 (Median = 8.9, IQR 31.3), POPDI-6 (Median = 0, IQR = 8.3), CRADI-8 (Median = 0, IQR = 10.7), and UDI-6 (Median = 0, IQR = 16.7). PFDI-20, POPDI-6, CRADI-8, and UDI-6 scores were significantly greater among women reporting isolated SUI (P < 0.0001, P = 0.04, P < 0.0001, P < 0.0001, respectively), UUI (P < 0.0001, P = 0.02, P < 0.0001, P < 0.0001, respectively), mixed UI (P < 0.0001 each), AI flatus (P < 0.0001 each), and AI stool (P < 0.0001 each) compared to those denying incontinence. Women with mixed UI had significantly greater PFDI-20 and UDI-6 scores compare to those with SUI (P < 0.0001) or UUI (P < 0.0001). Subjects with AI stool had significantly greater PFDI-20 and CRADI-8 scores compared to those with AI flatus (P = 0.01). Conclusions PFDI-20 scores from a sample of the general population correspond with the presence or absence of UI and AI. These normative and symptom-specific score distributions for the PFDI-20 provide reference points to gauge the effect of disease and intervention on quality of life for women with incontinence. Neurourol. Urodynam. 31:1252-1257, 2012.