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. About 11 minutes on average, and most people need no help with it.
- Five functional scales: physical, role, emotional, cognitive, and social.
- Three symptom scales (fatigue, nausea and vomiting, pain) and six single items (dyspnoea, insomnia, appetite loss, constipation, diarrhoea, financial difficulties).
- A two-item global health status and quality of life scale, on a 7-point response scale.
- All 15 scales and items are transformed to 0 to 100.
- Published by the EORTC Quality of Life Group.
What does the QLQ-C30 measure?
The QLQ-C30 is the core questionnaire that every EORTC cancer module is built on. Its 30 items produce 15 scores: five functional scales, three symptom scales, six single items, and a global health status and quality of life scale. No item appears in more than one scale. The structure below is version 3.0, the current standard.
| Scale | Items | A high score means |
|---|---|---|
| Global health status and quality of life | 2 | Better quality of life |
| Physical functioning | 5 | Better functioning |
| Role functioning | 2 | Better functioning |
| Emotional functioning | 4 | Better functioning |
| Cognitive functioning | 2 | Better functioning |
| Social functioning | 2 | Better functioning |
| Fatigue | 3 | More symptom burden |
| Nausea and vomiting | 2 | More symptom burden |
| Pain | 2 | More symptom burden |
| Dyspnoea | 1 | More symptom burden |
| Insomnia | 1 | More symptom burden |
| Appetite loss | 1 | More symptom burden |
| Constipation | 1 | More symptom burden |
| Diarrhoea | 1 | More symptom burden |
| Financial difficulties | 1 | More financial difficulty |
Disease-specific modules sit on top of the core. A brain tumour module or a lung module adds items for that cancer without replacing the C30, which is what lets results be compared across cancer types.
What does a QLQ-C30 score mean?
Every scale is transformed to 0 to 100. On the functional scales and the global scale a high score is good. On the symptom scales and the single items a high score means more burden. Reading the two directions the same way is the most common mistake with this questionnaire.
There are no published bands that mark a score as good or poor. The profile is read against reference values for a comparable group, or against the same person's earlier scores. What the literature does publish is how much change registers with the person answering. In a study of people receiving chemotherapy for breast cancer or small-cell lung cancer, the mean change in score matched their own descriptions as follows.
| Change in score | What patients called it |
|---|---|
| 5 to 10 | A little |
| 10 to 20 | Moderate |
| More than 20 | Very much |
The 15 scores are normally reported as a profile rather than collapsed into one number, though a single higher-order summary score has since been replicated and validated. The result is reference information for the care team, tracked over time.
How the QLQ-C30 is administered
- Administered by
- Self-administered. Most people complete it without assistance.
- Time to administer
- About 11 minutes on average
- Equipment
- The questionnaire and the EORTC scoring manual
- Cost
- Free to take here.
- Published by
- EORTC Quality of Life Group
- Copyright
- EORTC. The questionnaire and its modules may not be used without prior written consent.
- Age range
- Adults with cancer
The items are not reproduced here. The official questionnaire and its translations come from the EORTC Quality of Life Group.
Related instruments
QLQ-C30 questions, answered
How is the QLQ-C30 scored?
Every scale is handled the same way. Take the mean of the items in that scale, which is the raw score, then transform it linearly so the result runs from 0 to 100. Most items are answered on a four-point scale, and the two global health items on a seven-point scale, and the transformation accounts for that difference. Direction is what changes between scales. On the functional scales and the global scale a high score is good, and on the symptom scales and single items a high score means more burden.
What is a good QLQ-C30 score?
There is no cutoff that marks a score as good or bad. The QLQ-C30 is read as a profile of 15 numbers, against reference values for a comparable group or against the same person's earlier scores. What is published is how much change matters. In a study of people receiving chemotherapy, a change of 5 to 10 points was what patients themselves called a little change, 10 to 20 moderate, and more than 20 very much.
How long does the QLQ-C30 take?
About 11 minutes on average in the original international field study, and most patients required no assistance to complete it. Being short enough to sit alongside the trial paperwork was one of the design goals.
Is the EORTC QLQ-C30 free?
Yes. It is free to take here. The questionnaire itself is published by the EORTC Quality of Life Group, which is who to approach about administering it in your own practice.
Which version of the QLQ-C30 should be used?
Version 3.0. It is the standard version and EORTC says it should be used for all new studies unless a study needs to stay compatible with earlier data. Version 3.0 differs from version 2.0 by using four-point response scales for the first five items rather than yes and no. Version 2.0 in turn replaced the role functioning items from version 1.0, which were the only multi-item scale in the original field study to fall below the reliability standard.
How many items does the QLQ-C30 have?
Thirty. They form 15 scores: five functional scales, three symptom scales, six single items, and one global health status and quality of life scale. No item appears in more than one scale.
Does the QLQ-C30 diagnose anything?
No. It describes quality of life during and after cancer treatment and produces reference information for you and your care team.
Evidence, psychometrics and provenance
Developed by the EORTC Quality of Life Group and published in 1993, after a field study of 305 people with non-resectable lung cancer at centres in 13 countries. Version 2.0 revised the role functioning and overall health items. Version 3.0, the current standard, moved the first five items to four-point response scales.
Psychometrics
The original field study reported internal consistency scale by scale rather than as one coefficient for the questionnaire, so there is no single number to show for the QLQ-C30 as a whole.
- Internal consistency, original field study
- All multi-item scales met Cronbach α of 0.70 or above except role functioning (Aaronson et al., 1993)
- What changed since
- Version 2.0 replaced the role functioning items, with a marked improvement in internal consistency (EORTC scoring manual)
- Field study sample
- 305 people with non-resectable lung cancer across 13 countries
- Single summary score
- A higher-order summary score has been replicated and validated (Giesinger et al., 2016)
References
- 1.Aaronson NK, Ahmedzai S, Bergman B, et al. The European Organization for Research and Treatment of Cancer QLQ-C30: a quality-of-life instrument for use in international clinical trials in oncology. J Natl Cancer Inst. 1993;85(5):365-376.
- 2.Osoba D, Rodrigues G, Myles J, Zee B, Pater J. Interpreting the significance of changes in health-related quality-of-life scores. J Clin Oncol. 1998;16(1):139-144.
- 3.Giesinger JM, Kieffer JM, Fayers PM, et al. Replication and validation of higher order models demonstrated that a summary score for the EORTC QLQ-C30 is robust. J Clin Epidemiol. 2016;69:79-88.
- 4.Fayers PM, Aaronson NK, Bjordal K, et al. EORTC QLQ-C30 Scoring Manual. 3rd edition. Brussels: EORTC; 2001.
This assessment uses a validated instrument and is reference information, not a diagnosis.