Background: A limited number of headache disability indices exist that can evaluate and manage different disabilities related to headache among Iranian patients.
Objective: This study aimed to translate and validate the Persian version of the Henry Ford headache disability inventory (HDI).
Methods: The original questionnaire was translated and culturally adapted to the Persian setting. A total of 250 patients with chronic headache were enrolled in this study. The questionnaire's face validity, content validity, and convergent validity with Short-Form Health Survey (SF-36) were evaluated and a confirmatory factor analysis (CFA) was conducted. Its internal consistency was also assessed and its short- and long-term test-retest reliability were examined by intraclass correlation coefficient (ICC).
Results: The content validity indices were 0.85, 0.99, and 0.97 for simplicity, relevance, and clarity, respectively. The content validity ratio was calculated as one for all items. The findings of CFA confirmed that this index had a good fit. Cronbach's alpha was 0.91, 0.82, and 0.86 for the entire questionnaire as well as its functional and emotional subscales, respectively. The ICC was also calculated as 0.97 for the total inventory. The convergent validity showed significant negative correlations between HDI and short-form health survey items.
Conclusion: The validity and reliability of the Persian version of the HDI were confirmed. This questionnaire can explore the disabilities of Persian-speaking people with headache disorders.
Keywords: Disability; Headache; Quality of life; Questionnaire; Translation.
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