Validity and reliability of two Danish versions of the ICIQ-UI SF

Abstract

Introduction and hypothesis: We aimed to assess the validity and reliability of two Danish versions of the International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form (ICIQ-UI SF) in a female population. We hypothesized that the questionnaires had good predictive validity, internal consistency, patient-physician agreement, construct validity, test-retest reliability, and sensitivity to change.

Methods: To test the predictive validity, we compared the ICIQ-UI SF to urodynamics (n = 153). The same answers were used for testing the internal consistency. The patient-physician agreement was assessed by comparing the self-administered questionnaire with a physician's evaluation based on telephone interviews (n = 60). To test the construct validity, we calculated the proportion of scores ≥ 1 in questionnaires completed by women defining themselves as "not suffering from involuntary urination" (n = 69). Test-retest reliability was assessed by comparing questionnaires completed twice with an interval of 2 weeks (n = 186). Sensitivity to change was evaluated by analyzing answers before and after treatment for women treated surgically for stress urinary incontinence (n = 755) and with botulinum type A toxin for overactive bladder (n = 63).

Results: Predictive validity: 26.6-27.6% agreement. Internal consistency: Cronbach's alpha: 0.7-0.8. Patient-physician agreement: 53.9-92.9% agreement. Some interview participants misunderstood the word "leak." Construct validity: 19% and 23% had a total score ≥ 1. Test-retest reliability: 77.0-95.7% agreement. Sensitivity to change: Significantly lower score after treatment.

Conclusion: The ICIQ-UI SF had excellent internal consistency, patient-physician agreement, test-retest reliability, and sensitivity to change. The ICIQ-UI SF had questionable predictive validity and construct validity compared to urodynamic testing. We recommend precaution in diagnostics or research based solely on the questionnaire.

Keywords: Psychometrics; Questionnaire; Reliability; Urinary incontinence; Validity.