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.