European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30)
A 30-item quality-of-life questionnaire covering function, symptoms, and global health status.
By Claire White
- Self-administered; approximately 10 to 15 minutes.
- Five functional scales: physical, role, emotional, cognitive, social.
- Nine symptom scales/items: fatigue, nausea and vomiting, pain, dyspnoea, insomnia, appetite loss, constipation, diarrhoea, financial difficulties.
- Two global quality-of-life items: overall health and overall quality of life (1–7 scale).
- Reference information. It does not diagnose.
What it measures
The QLQ-C30 measures quality of life across functional domains (physical, role, emotional, cognitive, and social) and symptoms commonly experienced by patients. Most items use a 4-point frequency scale (not at all to very much). Global health status uses a 7-point scale. All scores are linearly transformed to 0–100. For functional scales, higher scores mean better functioning; for symptom scales, higher scores mean more burden.
What the result tells you
Scale and item scores (0–100) profile the person’s quality of life across domains. Functional scale scores close to 100 indicate good function. Symptom scores close to 0 indicate low symptom burden. The QLQ-C30 is used in oncology clinical trials and has been adapted for specific cancers (brain, lung, etc.) with supplementary modules.
Evidence, psychometrics and provenance
Psychometrics
- Internal consistency (functional scales)
- Cronbach α ≥ 0.70
- Test-retest reliability
- r = 0.76–0.89 across scales