# EORTC QLQ-C30: the questionnaire most cancer trials use

Source: https://onco.cc/technologies/rejuv-measure-eortc-qlq-c30/  
OnCo record `rejuv-measure-eortc-qlq-c30` (Technology). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

Thirty questions, answered about the past week, that produce separate scores out of 100 for how the body works, how the mind is, and for fatigue, pain and sickness. It is the questionnaire behind most European cancer trial results about quality of life, and there are add-on modules for individual cancers.

## Summary

The EORTC QLQ-C30 was built by the European Organisation for Research and Treatment of Cancer from 1986 and reported in 1993. Its own description of its structure is that it "incorporates nine multi-item scales: five functional scales (physical, role, cognitive, emotional, and social); three symptom scales (fatigue, pain, and nausea and vomiting); and a global health and quality-of-life scale", with "several single-item symptom measures" as well, covering breathlessness, appetite loss, sleep, constipation, diarrhoea and financial difficulty.

It was field-tested in 305 people with non-resectable lung cancer across 13 countries. The paper reports that "the average time required to complete the questionnaire was approximately 11 minutes, and most patients required no assistance". It also reports its own weak point rather than hiding it: role functioning, meaning work and household activities, "was also the only multi-item scale that failed to meet the minimal standards for reliability" either before or during treatment. That two-item role scale is still in use and is still the noisiest part of the instrument.

Scoring. Raw item scores are linearly transformed to a 0 to 100 scale. On the functional scales and on global health, higher is better; on the symptom scales and single items, higher is worse. This is the commonest misreading of a QLQ-C30 result: a rise of ten points on fatigue is a deterioration, not an improvement.

Modules. The core thirty questions are designed to be given with a disease-specific or treatment-specific module, so a breast trial adds QLQ-BR23 or its successor BR45, a lung trial adds LC13 or LC29, a colorectal trial CR29, a prostate trial PR25, a head and neck trial H&N35 or HN43. The modules are where the questions a patient actually recognises tend to live: bowel urgency, hot flushes, mouth dryness, hair loss, sexual function.

What a change means is covered separately on the minimally important difference record; the short version is that the EORTC's own guidance puts a medium difference at between 9 and 19 points depending on the scale, and the disease-specific anchor studies put most meaningful changes between 4 and 14 points.

What it misses. One cognitive scale of two items, asking about concentration and memory, which is not a measure of cognition in any neuropsychological sense. No question about fear of recurrence, the most reported unmet need after treatment. No question about body image or intimacy in the core thirty, which is why the modules exist. And a recall period of one week, which captures a chemotherapy nadir or misses it depending on the day the form was handed over.

## Fields

- Kind: Technology
- Status: standard-of-care
- Last checked: 2026-10-02
- Tags: rejuvenation; survivorship; measurement; instruments
- Principle: A core generic cancer questionnaire plus a disease-specific module: the core allows pooling and comparison across cancers, the module supplies the sensitivity to the symptoms that matter in one disease. Items are scored on four-point verbal scales except global health, which is a seven-point scale, and transformed to a 0 to 100 range.
- Since: 1993
- Strengths: Used in most international cancer trials, so results can be compared and pooled; Validated across many languages and cultures from the first study; Disease-specific modules exist for most common cancers; Published interpretation guidance for nearly every scale
- Limitations: The role functioning scale failed the reliability standard in its own validation paper and still does; Two items are the whole cognitive scale; Direction of scoring is inverted between functional and symptom scales and is often misread; Nothing on fear of recurrence in the core questionnaire

## Sources

- Wikipedia: https://en.wikipedia.org/wiki/EORTC_QLQ-C30
- Aaronson 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 (JNCI 1993): https://doi.org/10.1093/jnci/85.5.365
- Osoba et al., Interpreting the significance of changes in health-related quality-of-life scores (JCO 1998): https://doi.org/10.1200/JCO.1998.16.1.139
- Cocks et al., Evidence-based guidelines for determination of sample size and interpretation of the EORTC QLQ-C30 (JCO 2011): https://doi.org/10.1200/JCO.2010.28.0107
- Musoro et al., Minimally important differences for interpreting EORTC QLQ-C30 scores in patients with advanced breast cancer (JNCI Cancer Spectrum 2019): https://doi.org/10.1093/jncics/pkz037
- Koller et al., Minimally important differences of EORTC QLQ-C30 scales in patients with lung cancer or malignant pleural mesothelioma (Lung Cancer 2022): https://doi.org/10.1016/j.lungcan.2022.03.018
- Gamper et al., Minimally important differences for the EORTC QLQ-C30 in prostate cancer clinical trials (BMC Cancer 2021): https://doi.org/10.1186/s12885-021-08609-7

## Connected records

- technologies: [Asking people how they are, every week, as a treatment in its own right](https://onco.cc/technologies/rejuv-measure-epro-as-treatment/), [Electronic patient-reported outcome (ePRO) symptom monitoring](https://onco.cc/technologies/epro-symptom-monitoring/), [FACT-G and the FACIT family: the other main questionnaire](https://onco.cc/technologies/rejuv-measure-fact-and-facit/), [Fear that the cancer will come back: how common it is, and when it stops being ordinary worry](https://onco.cc/technologies/rejuv-mind-fear-of-recurrence/), [How recovery is measured: the questionnaires behind the numbers](https://onco.cc/technologies/rejuv-measure-patient-reported-outcomes/), [Measuring memory and concentration after treatment](https://onco.cc/technologies/rejuv-measure-cognitive-function/), [PRO-CTCAE: side effects graded by the person having them](https://onco.cc/technologies/rejuv-measure-pro-ctcae/), [PROMIS: the item banks that let a short questionnaire be precise](https://onco.cc/technologies/rejuv-measure-promis/), [What a difference has to be before a person would notice it](https://onco.cc/technologies/rejuv-measure-minimally-important-difference/)
- cancers: [Colorectal cancer](https://onco.cc/cancers/colorectal/), [Head and neck squamous cell carcinoma](https://onco.cc/cancers/head-and-neck/), [HR-positive / HER2-negative breast cancer](https://onco.cc/cancers/breast-hr-positive/), [Mesothelioma](https://onco.cc/cancers/mesothelioma/), [Non-small-cell lung cancer](https://onco.cc/cancers/nsclc/), [Prostate cancer](https://onco.cc/cancers/prostate/)
- fronts: [Recovery & Rejuvenation](https://onco.cc/fronts/rejuvenation/), [Supportive Care & Survivorship](https://onco.cc/fronts/supportive-care/)
- terms: [Cancer-related fatigue (tiredness)](https://onco.cc/terms/cancer-related-fatigue/), [Quality of life](https://onco.cc/terms/quality-of-life/)
- bottlenecks: [Patients lack understanding, navigation and agency](https://onco.cc/bottlenecks/b-patient-voice/), [Toxicity and quality of life are undervalued](https://onco.cc/bottlenecks/b-toxicity-qol/)

---
JSON: https://onco.cc/api/v1/entities/rejuv-measure-eortc-qlq-c30.json