Validation of Quality of Life Instruments for Cancer Patients – Colorectal Cancer (QLICP-CR) in patients with colorectal cancer in Northeast China

BACKGROUND: Measuring quality of life is important for cancer patients, but there are regional differences in age-standardized colorectal cancer incidence and mortality rates which may affect measurement. This study aimed to evaluate the reliability, validity and responsiveness of Quality of Life Instruments for Cancer Patients – Colorectal Cancer (QLICP-CR) in colorectal cancer patients in Northeast China, and assess its usefulness for evaluation of quality of life in these patients. METHODS: From November 2016 to January 2017, 152 patients with colorectal cancer from Liaoning Cancer Hospital & Institute were surveyed three times using QLICP-CR and the Functional Assessment of Cancer Therapy – Colorectal (FACT-C) to measure their quality of life (on admission, 2–3 days later and at discharge). Reliability was evaluated by internal consistency and test–retest reliability. Validity was examined by item–domain correlation, criterion-related validity and factor construct validity analysis. Responsiveness was assessed using paired Student’s t tests and calculating standardized response mean. RESULTS: Cronbach’s α coefficient for QLICP-CR ranged from 0.62 to 0.93. Pearson correlation and intra-class correlation coefficients for QLICP-GM, the five domains and the total scale of QLICP-CR ranged from 0.74 to 0.91 and 0.74 to 0.90. The item–domain correlation analysis showed good convergent validity and discriminant validity. Correlation analysis of domain scores between FACT-C and QLICP-CR showed good criterion-related validity. Exploratory factor analysis revealed that nine and three principal components were extracted from items in the two modules of QLICP-CR, and the contribution rate of cumulative variance was 70.21 and 72.26%. There were significant differences in quality of life between the first and the third measurements, with standardized response mean values ranging from 0.30 to 0.81. CONCLUSIONS: The QLICP-CR was a reliable, valid and sensitive instrument to measure quality of life in colorectal cancer patients in Northeast China.