[Translation and validation into Portuguese of a questionnaire to evaluate the severity of urinary incontinence].

Purpose: to translate into Portuguese, culturally adapt and validate the Incontinence Severity Index (ISI) questionnaire.

Methods: two Brazilian translators carried out the translation of the ISI into Portuguese and a version was generated by consensus. This version was back-translated by two other native English speaking translators. The differences between versions were resolved and the version was pre-tested in a pilot study. One week later, the ISI was reapplied to complete the retest. The final version of the ISI was applied together with the one-hour pad test to women with stress urinary incontinence. For the validation of the ISI, the reliability (internal consistency and test-retest) and the construct were evaluated.

Results: the reliability of the instrument was tested using the Cronbach α coefficient, with a general result of 0.93, demonstrating excellent reliability and consistency of the instrument. The intraclass correlation coefficient and the standard errors of measurement were 0.96 and 0.43, respectively. The Pearson correlation revealed a strong positive correlation (r=0.72, p<0.0001) between the results of the ISI questionnaire and the one-hour pad test.

Conclusion: the culturally adapted version of the ISI translated into Brazilian Portuguese presented satisfactory reliability and survey validity and was considered to be valid for the evaluation of the severity of urinary incontinence.