Validity and reliability of the MD Anderson dysphagia inventory in English and Chinese in head and neck cancer patients.

Abstract

Patient-reported outcome measures are important in assessing the impact of dysphagia on quality of life. Our aim was to adapt and examine the cultural validity and reliability of a swallowing-related quality of life measure, the MD Anderson Dysphagia Inventory (MDADI), in English and Chinese, with head and neck cancer patients. We adapted the MDADI to Chinese through formal forward-backward translation. Sixty-six head and neck cancer survivors completed the MDADI, Swallowing Quality of Life (SWAL-QOL) questionnaire and Hospital Anxiety and Depression Scale (HADS) in English or Chinese. Swallowing status was scored on the Functional Oral Intake Scale (FOIS). Seventy-four percent (n = 49) of participants completed a repeat administration of the MDADI for test-retest reliability analysis. The MDADI showed high internal consistency reliability (Cronbach's α , 0.82≤α≤0.94), and test-retest reliability in both English (intraclass correlation coefficient, ICC = 0.81) and Chinese (ICC = 0.72). Criterion validity was established through moderate to strong correlations with relevant SWAL-QOL domains. Convergent validity was determined by significant correlations to the HADS and FOIS. Divergent validity was determined by nonsignificant association to the SWAL-QOL Sleep domain. The MDADI also presented as hypothesised to most known-group theoretical constructs. The MDADI showed good psychometric properties in English and Chinese. This avails a reliable and psychometrically valid MDADI for Chinese speakers.