Abstract: The purpose of this study was to evaluate the psychometric properties and clinical validity of the EORTC QLQ-C30 in a sample of cancer patients in China. 289 cancer patients were randomly assigned to one of four conditions factorial design. The data showed that: within all scales, items correlated significantly higher with its own scale than with another scale; the most scales structure of questionnaire were similar to the data of EORTC except a little difference, which might be due to cultural difference. Validity was shown by hoe findings: first while all interscale correlations were statistically significant the correlation was moderate, indicating that the scales were assessing distinct components of the quality of life construct; second, most of the functional (except social, cognitive function) and symptom measures discriminated clearly between patients differing in clinical status as defined by the Karnofsky performance status scale; third, there were changes (some of them were statistically significant changes) in the expected direction, in all scales, for patients whose performance status had improved or worsened during the course of treatment. These results support the EORTC QLQ-C30 as a reliable, responsive, and valid measure of the quality of life of cancer patients in clinical research settings in China.

Key words: Cancer patients, Quality of life, QLQ-C30, China