Psychometric evaluation of Oral Mucositis Daily Questionnaire: A cross-cultural adaptation of the Malay version in multiethnic adult autologous stem cell transplant

OBJECTIVE: Mucositis is one of the most feared side effects of cancer treatment. Psychometric analysis of a patient self-assessment score, the oral mucositis daily questionnaire in Malay (OMDQ-Mal) and its construct validity by means of confirmatory factor analysis (CFA) is lacking. This research aimed to test the validity and reliability of OMDQ-Mal. METHODS: A total of 114 autologous stem-cell transplantation patients aged ≥ 18 years old at a national hematology center in Malaysia from April 2019 to December 2020 completed OMDQ-Mal concurrently with physician scores. Internal consistency and reproducibility were determined by Cronbach alpha and intraclass correlation coefficient, respectively. Correlations with physician scores were determined by Spearman correlation. Discriminative validity and construct validity were determined by Mann–Whitney U and CFA, respectively. RESULTS: OMDQ-Mal demonstrated high internal consistency (α ​= ​0.874). Test–retest reliability between paired days were moderate to excellent (95% CI ​= ​0.676–0.953). Items in OMDQ-Mal had moderate to strong correlations with physician scores (ρ ​= ​0.503–0.721). Discriminative validity indicated that the scores of scales were significantly different between participants with severe and mild conditions. Construct validity results of loading factors 0.708–0.952; composite reliability 0.879–0.974; average variant extracted 0.710–0.841; and heterotrait–monotrait ratio 0.528 established the convergent and divergent validity. CONCLUSIONS: In conclusion, the OMDQ-Mal, which captured important quality of life responses, demonstrated adequate validity and reliability. This was supported by a two-component model CFA. The strong correlation of OMDQ-Mal with both physician scores indicated its potential as a comprehensive patient-reported outcome measure of mucositis of the entire alimentary tract.