Testing of the Incontinence Impact Questionnaire (IIQ-7) with men after radical prostatectomy.

OBJECTIVE

The objective of this study was to test the validity and reliability of the Incontinence Impact Questionnaire (IIQ-7), a 7-item self-report instrument designed to assess the impact of urinary incontinence (UI), in men.

SUBJECTS

Fifty-eight men with incontinence after radical prostatectomy were the subjects of the study.

METHODS

Content validity was assessed by a panel of experts. Construct and criterion validity were examined with 3 groups of men who had UI in a randomized controlled trial comparing pelvic muscle exercises with pelvic muscle exercises plus electrical stimulation. Internal consistency and stability coefficients for the IIQ-7 were determined.

RESULTS

The content validity index was 0.88. Four items were below the designated content validity index level. A 2-factor analysis solution (factor I-impact on daily activities; factor II-emotional impact) explained 84.94% of the variance. No significant group differences were recorded on impact of UI (F = 0.37, P =.70), nor were any differences among subjects found over time (F = 0.90, P =.50). A positive relationship was found between grams of urine loss on a 24-hour pad test and IIQ-7 scores (r = 0.34, P =.003 to.51, P =.001). When the IIQ-7 score decreased, self-reported quality of life improved as measured by the European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire Version 2 (r = -0.57, P =.0001 to -.49, P =.001). A strong relationship was found between responses to the question "Does leakage affect your life?" and the IIQ-7 scores. Internal consistency ranged between 0.88 and 0.92. IIQ-7 scores were consistent when urine loss was stabilized between 16 and 24 weeks after entry into the study (r = 0.89, P =.0001).

CONCLUSION

The IIQ-7 is a reliable measure of the impact of UI; however, the scale requires additional testing regarding construct validity in men.