Analysis

The EORTC Quality of Life Questionnaire (European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire) was developed by the European Organisation for Research and Treatment of Cancer to measure the quality of life of cancer patients. The QLQ-C30 includes a wide range of dimensions related to health and well-being of cancer patients, making it one of the most widely used tools for assessing quality of life in clinical studies and clinical practice.

Objective

The main objective of the QLQ-C30 is to evaluate the quality of life of cancer patients, taking into account the effects of the disease and its treatment on various aspects of their lives.

Scoring

The QLQ-C30 consists of 30 questions covering five functional scales (physical, emotional, cognitive, social functioning, and role functioning), three symptom scales (fatigue, pain, nausea/vomiting), and one global health and quality of life scale.
Participants are asked to rate their responses on a 4-point Likert scale, from 1 (not at all) to 4 (very much), with some questions rated on a 7-point Likert scale, from 1 (very poor) to 7 (excellent).
The overall score for each scale is calculated from the sum of individual question scores and converted to a scale from 0 to 100. Higher scores on functional scales indicate better functioning, while higher scores on symptom scales indicate greater symptom severity.

References

Aaronson, N. K., Ahmedzai, S., Bergman, B., Bullinger, M., Cull, A., Duez, N. J., … & Takeda, F. (1993). The European Organization for Research and Treatment of Cancer QLQ-C30: A quality-of-life instrument for use in international clinical trials in oncology. Journal of the National Cancer Institute, 85(5), 365-376.
Fayers, P., Aaronson, N., Bjordal, K., Groenvold, M., Curran, D., & Bottomley, A. (2001). The EORTC QLQ-C30 Scoring Manual (3rd edition). European Organisation for Research and Treatment of Cancer, Brussels.