Psychometric validation of the Italian version of the I-QoL questionnaire: clinical and urodynamic findings.

INTRODUCTION AND HYPOTHESIS: The aim was to validate the Italian version of the Incontinence-Quality of Life questionnaire (I-QoL) in women with clinical and urodynamic urinary incontinence (UI). A secondary end point was to compare the results of women with reported UI, but negative urodynamic findings. METHODS: The Italian translation of the I-QoL was administered to 267 Italian women with pelvic organ prolapse < stage III, and who had undergone previous surgical or medical therapy for UI. Cronbach's alpha was calculated to assess internal consistency of the I-QoL items. Reproducibility was assessed using the intraclass correlation coefficient (ICC). Convergent validity involved comparison of I-QoL scores and the Short Form-36 Health questionnaire. RESULTS: One hundred and sixty-seven patients were considered for the primary end point: 47 had a negative history of UI and a normal urodynamic test, 120 complained of UI confirmed by a urodynamic test, 59 had a positive history for UI and a urodynamic test negative for UI, and 35 patients not reporting UI had a positive urodynamic test. The I-QoL score revealed that the QoL was lower in patients with reported UI, irrespective of urodynamic findings. The overall I-QoL summary score and subscales showed high internal consistency (alpha ranges from 0.88 to 0.96). ICC ranged from 0.98 to 0.99, demonstrating the stability of the scores. The physical domain of the I-QoL showed a 0.27 correlation with the physical functioning subscale of the SF-36. No significant difference in I-QoL scores was found among various types of UI. CONCLUSION: The Italian translated version of the I-QoL is reliable, consistent and a valid instrument for assessing impact on quality of life in Italian speaking women with UI.