Validation of the Fecal Incontinence Severity Index in a Turkish Population

Aim: The aim of this study was to validate the Turkish-translated version of the Fecal Incontinence Severity Index (FISI) for Turkish-speaking patients. Methods: This prospective cohort study included 58 patients: 22 (37.9%) scored 0 (no incontinence), and the remaining 36 (62.1%) scored at least 1 (any level of gas, mucus, liquid, solid incontinence, pad wear, or lifestyle alteration). Test-retest reliability analysis, internal consistency analysis, content-face validity, and criterion validity were used to evaluate the Turkish version of the FISI. Validity of the criteria was assessed through correlation analyses between patient and surgeon scores of FISI and manometric measurement between patients with or without anal incontinence symptoms. Results: The 2-week test-retest revealed significant correlation (P < 0.001). The Cronbach alpha values of the translated version for total scores of the scale were 0.735 and 0.734 for patient-rated scores and surgeon-rated scores, respectively, and indicate a high degree of internal consistency in each item of the questionnaire. Total and all subgroup scores of the FISI scale showed significant correlation with the maximal squeeze pressure and resting pressure values. Comparison of maximal squeeze pressure and resting pressure values of both groups showed significant differences between women with no incontinence and women with any form of incontinence. Conclusions: The Turkish-translated version of the FISI is a reliable, consistent, and valid instrument for assessing the patient-rated symptom severity among women with anal incontinence in a Turkish-speaking population.