Data collection
EQF, multiple primary tumors, colorectal, breast cancer, Cancer
ONCOLOGY, SOLID TUMORS, METASTATIC CANCER, CANCER
This research used data from Quality of Life Mapping Algorithm for Cancer (QOL-MAC) study’s data that mainly purported to develop mapping algorithms for the EORTC QLQ-C30 and the FACT-G on the EQ-5D-5L index. Its details have been published elsewhere [In the QOL-MAC research, patients with unresectable, locally advanced, recurrent, or metastatic cancers were recruited from 14 hospitals in Japan from November 2018 to March 2019. The eligible patients had lung, stomach, colorectal, breast cancer, or other solid tumors; they were aged 20 years or above and were undergoing drug therapy, with an Eastern Cooperative Oncology Group (ECOG) performance status of 0–3. Those who were receiving treatment for multiple primary tumors or were unable to respond to the questionnaires were excluded. All enrolled patients provided written informed consent before participating in the study.We utilized those questionnaire booklets that contained the EQ-5D-5L, FACT-G, and EORTC QLQ-C30 in different orders; let us denote them as E, F, and Q, respectively. We created six types of questionnaire booklets, each of which contained the HRQOL instruments in any of the following orders: EFQ, EQF, FEQ, QEF, FQE, or QFE. For example, EFQ represents questionnaire booklets comprising the HRQOL instruments in the following order: EQ-5D-5L > FACT-G > EORTC QLQ-C30. We designed the booklets in such a manner that the medical staff could not identify these measures’ order by observing their covers.We distributed the questionnaire booklets to the patients by a quasi-randomization design using the order in which patients enrolled; therefore, each patient was assigned to any of the six groups defined by its types. Firstly, we repeatedly lined the six questionnaire booklet types in a fixed order (specifically, EFQ > EQF > FQE > FEQ > QFE > QEF) and sent them to all hospitals. Subsequently, each hospital’s medical staff recruited the patients and distributed the questionnaire booklets in the aforementioned order. Finally, the patients answered the questionnaire booklets, which were principally collected in the hospital. When this was unfeasible, the patients returned them directly to the data center.