Mapping functions of cancer patients' quality of life in Indonesia: from EORTC-QlQ -C-30 to EQ-5D-5L

Abstract

The instruments for measuring cancer patients’ quality of life are available for many cancer types, but none of them are showing a utility score. It is important to map the functions of the specific instruments into the generic instrument to get the utility score. This study is aimed to define the mapping of functions in the Indonesian version of EORTC QLQ C-30 into the Indonesian version of EQ-5D-5L. We collected data and QoL from 469 patients in some hospitals in central Java and Sumatera, Indonesia. The inclusion criteria were adult cancer patients who were treated with chemotherapy. Patients were excluded if had comorbidities, complications, or were pregnant and during lactation. We performed OLS regression for getting the mapping. Our subjects were dominated by females, with advanced stages of cancer and between 25-59 yo (69.4%; 54.1%; 86%, respectively). The global health score of EORTC QLQ C-30 is lower than the VAS of EQ-5D-5L. The most symptom experienced is pain. We got two models for mapping functions of the questionnaire, and model 2 had better performance with lower values of MAE and RMSE. Model 2 involves physical, role, and emotional functions, pain, dyspnea, insomnia, and financial difficulties as the variable which can be mapped into EQ-5D-5L. Our study found that some functions in EORTC QLQ C-30 had a significant correlation with EQ 5D 5L domains. These results can be used to get the utility value of Indonesian cancer patients, and they can be applied to define the cost-utility of the targeted drug for cancer.