The objectives were to translate and culturally adapt the M.D. Anderson Dysphagia Inventory (MDADI) into Danish and subsequently test the reliability of the Danish version. The MDADI was translated into Danish and cross culturally adapted through cognitive interviews. The final version was test-retest evaluated in a group of head and neck cancer (HNC) patients who responded to the questionnaire twice with a mean of eight days apart. Interclass correlation coefficient, Cronbach's alpha, floor and ceiling effects, standard error of measurement and minimal detectable change were investigated. Fourteen patients were interviewed on the comprehensibility of the Danish MDADI, and all found the questionnaire meaningful, easy to understand, non-offensive and to include relevant aspects of dysphagia related to HNC. Sixty-four patients were included in the test-retest study. Especially, one item in the emotional scale (E7) appeared to be often misinterpreted, and ceiling effects were found in all four subdomains (global, emotional, functional and physical). The four subdomains and the composite score showed acceptable test-retest reliability and internal consistency in a Danish population of HNC patients. The Danish MDADI is reliable in terms of internal consistency and test-retest reproducibility and can be used in assessing the health-related quality of life in head and neck cancer patients with dysphagia.
Keywords: Deglutition; Deglutition disorders; Internal consistency; MDADI; Patient reported outcome measures; Test-retest.