Table 1 Quality of life instruments used in the study

European Organization for Research and Treatment of Cancer QLQ-C30 (EORTC QLQ-C30) [32]

EORTC QLQ-C30 is a general cancer instrument containing multiple items, measured in multiple-point Likert scales, that reflect the multidimensionality of QOL construct [32]. It includes five functional domains (physical, role, cognitive, emotional and social), three symptom domains (fatigue, pain, nausea and vomiting), and a global health and QOL domain. Six single items assess common symptoms in cancer patients (dyspnea, appetite loss, sleep disturbance, constipation and diarrhea) and financial problem. All scales and domains are transformed to scores ranging from 0 to 100. A lower score for a functional or global QOL scale reflects a poorer functioning level or global QOL, while a lower score for a symptom/problem scale reflects less symptoms/problem (better QOL).

European Organization for Research and Treatment of Cancer QLQ-HCC18 (EORTC QLQ-HCC18) [33]

EORTC QLQ-HCC18 includes eighteen multiple item scales organized into six domains (fatigue, body image, jaundice, nutrition, pain and fever) and two items (abdominal swelling and sex life) [33]. All scales are grouped and transformed to score ranging from 0 to 100. A lower score represents a less severe symptom/problem (better QOL). EORTC QLQ-HCC18 is used together with EORTC QLQ-C30.

C30 index score [30]

∑ [(100-Physical functioning), (100-Role functioning), (100-Emotional functioning), (100-Cognitive functioning), (100-Social functioning), (100-global QOL), scores of Fatigue, Nausea and vomiting, Pain, Dyspnoea, Insomnia, Appetite loss, Constipation, Diarrhea, Financial Diffculty] ÷ 15. (remarks: a lower score represents a less severe symptom/problem)

HCC18 index score [30]

∑(scores of Fatigue, Body Image, Jaundice, Nutrition, Pain, Fever, Sex life, Abdominal distension) ÷ 8. (remarks: a lower score represents a less severe symptom/problem)