Translation and validation of the Chinese version of the quality of life radiation therapy instrument and the head & neck module (QOL-RTI/H&N)

BACKGROUND To translate and validate the Chinese version of the Quality Of Life Radiation Therapy Instrument and the Head & Neck Module (QOL-RTI/H&N), a disease-specific scale to measure quality of life (QOL) for patients with head and neck cancer (HNC) who received radiotherapy. METHODS The QOL-RTI/H&N was translated and validated according to the standard process: a translation and back-translation procedure, pilot testing and a validation study. HNC patients were enrolled from the Cancer Center of Sun Yat-sen University and assessed using the QOL-RTI/H&N, QLQ-C30 and QLQ-H&N35. Reliability (internal consistency reliability, split-half reliability and test-retest reliability), validity (content validity, construct validity, criterion validity and discriminant validity), and responsiveness analysis were performed to evaluate the psychometric characteristics of the QOL-RTI/H&N. RESULTS A total of 238 patients (99.2%) completed the questionnaire. Item RTI23 had 16.0% missing data. Other items had low percentages of missing data (0.4% or 0.8%) or no missing data. The average time to finish the scale was 9.8 minutes. Cronbach's alpha of the domains ranged from 0.41 to 0.77. The split-half reliability coefficients ranged from 0.43 to 0.77. All of the intra-class correlation coefficients were equal to or greater than 0.8. All of the item-own domain correlation coefficients were greater than those of the item-other domain. Confirmatory factor analysis showed that Comparative Fit Index, Normed Fit Index and Non-Normed Fit Index were equal to 1.00. Root Mean Square Error of Approximation was 0.01, with 90% CI (0.00, 0.10). The domain scores of the QOL-RTI/H&N were significantly correlated with those of the QLQ-C30 or QLQ-H&N3. All domain scores of patients in different radiotherapy stages were statistically significant (P < 0.05), apart from the speech domain. CONCLUSIONS The Chinese version of the QOL-RTI/H&N is a valid, reliable and responsive scale to measure QOL in HNC patients and can be used to assess the effects of radiotherapy treatment on these patients.