Objectives: This study aimed to examine the validity and reliability of a Web-based version of the epidemiology of prolapse and incontinence questionnaire (EPIQ).
Methods: Participants included 876 women age 38 to 65 years attending primary care clinics in the Salt Lake Valley. Women completed a single Web- or paper-based version of the symptom bother questions from EPIQ, and a subset repeated the same or opposite method at 2 separate time points. To assess subscales for the Web-based version factor, analysis of the 22 EPIQ items related to pelvic floor disorder symptoms was performed using principal components analysis and varimax rotation. Internal consistency was assessed using coefficient α. Test-retest and intermethod reliability were assessed using intraclass correlation coefficients for domain scores. Correlations above 0.70 were considered acceptable.
Results: Overall, 384 and 492 women completed at least 1 Web and 1 paper EPIQ and 93% were white with mean age of 50 (7) years. Of these, 63 completed Web-Web, 57 Web-paper, 47 paper-Web, and 109 paper-paper test-retest. Overall, factor analyses were consistent with the 7 domains of the original EPIQ. Cronbach α for the 4 symptomatic pelvic floor disorder domains and range of test-retest reliability for the various administration methods were similar to the original EPIQ instrument. Correlations for domain scores were above 0.70, except the anal incontinence scale (intraclass correlation coefficients, 0.68.)
Conclusions: Web administration of the EPIQ has similar psychometric properties with comparable internal consistency and test-retest reliability when administered in the same modality. Reliability between both methods of administration is acceptable.