Validation of the Chinese version of the EORTC colorectal cancer-specific quality-of-life questionnaire module (QLQ-CR38).

The European Organization for Research and Treatment of Cancer colorectal cancer (CRC)-specific quality-of-life questionnaire module (QLQ-CR38) assesses health-related quality of life in patients with CRC. We studied its psychometric properties and clinical validity in Hong Kong Chinese patients with CRC. The 38 items, forming functional and symptom scales, were administered to 256 Chinese patients diagnosed with CRC from a clinical oncology outpatient unit. Multitrait scaling analyses confirmed the hypothesized scale structure of the functional scales but not of the symptom scales, particularly those measuring chemotherapy side effects and gastrointestinal symptoms. The functional scales, but not the symptom scales, showed good internal consistency reliability. Convergent and divergent validity were satisfactory, as indicated by the correlations with other measures. The scales effectively differentiated between clinically distinct patient groups. As expected from a module designed to be used in conjunction with the core questionnaire, correlations between the QLQ-CR38 and the QLQ-30 are only weak to moderate. The functional scales of the Chinese version of the QLQ-CR38 show good psychometric performance and suitability for use with the QLQ-C30. Although, the results lend support to the clinical validity of the QLQ-C38, the symptom scales would benefit from further refinement to enhance their usefulness.