Validation of the Portuguese version of the King's Health Questionnaire for urinary incontinent women

Abstract

OBJECTIVE: To translate into Portuguese and evaluate the condition-specific quality of life King's Health Questionnaire (KHQ) for female urinary incontinence. METHODS: Two Brazilian translators, aware of the aim of the project, prepared two versions of the KHQ into Portuguese, which were back-translated into English by two other English translators. The differences were harmonized and pre-tested in a pilot study. The final version of the KHQ and the "Short-Form Health Survey" (SF-36), which has already been translated and validated into Portuguese were simultaneously administered to 156 and 119 women respectively. KHQ's psychometric properties such as reliability (internal consistency and retest) and construct validity were tested. A retest was performed within 2 weeks from the start date. RESULTS: The cultural adjustment process resulted in no changes in the KHQ Portuguese version, although for low schooling patients the questionnaire had to be read by the researcher during face-to-face interview. For all other patients, the KHQ was self-administered. KHQ's standardized Cronbach's alpha was 0.87 and when assessed by domains ranged from 0.49 to 0.92. Reliability measured by intraclass correlation (ICC) was considered moderate to strong for all domains and the severity measure scale ranged from 0.53 to 0.81. Pearson´s correlation coefficient between KHQ and SF-36 was considered weak to moderate in the majority of the related domains, ranging from -0.27 to -0.53. CONCLUSIONS: The KHQ Portuguese version was translated and adjusted for Brazilian women with urinary incontinence complaints. It represents an important tool for the assessment of incontinent women in clinical trials.