Validity and Reliability of the Korean Version of the MD Anderson Dysphagia Inventory for Head and Neck Cancer Patients

Objective To translate the MD Anderson Dysphagia Inventory (MDADI) which is a self-administered questionnaire that assesses effect of dysphagia on the quality of life for patients with head and neck cancer, into Korean and to verify the validity and reliability of the Korean version of MDADI. Methods We performed 6 steps for the cross-cultural adaptation which consisted of translation, synthesis, back translation, review by an expert committee, cognitive debriefing, and final proof reading. A total of 34 dysphagia patients with head and neck cancers from Seoul National University Hospital answered the translated version of the questionnaire for the pre-testing. The patients answered the same questionnaire 2 weeks later to verify the test-retest reliability. Results One patient was excluded at second survey because he changed his feeding strategy. Overall, 33 patients completed the study. Linguistic validations were achieved by each step of cross-cultural adaptation. We gathered statistically strong construct validity (Spearman rho for subdomain scores to total score correlation range from 0.852 to 0.927), internal consistency for subdomains (Cronbach's alpha coefficients range from 0.785 to 0.889) and test-retest reliability (intra-class correlation coefficient range from 0.820 to 0.955) Conclusion The Korean version of the MDADI achieved linguistic validations and demonstrated good construct validity and reliability. It can be a useful tool for screening and treatment planning for the dysphagia of patients with head and neck cancers.