Aims: We wanted to develop a shortened version of the EORTC QLQ-C30, an extensively validated questionnaire used in more than 3,000 cancer studies, to make it more suitable for palliative care patients.
Results: obtained with the shortened version should be directly comparable with scores on the original QLQ-C30.
Methods: Two approaches were used: (1) Shortening multi-item scales using Item Response Theory (IRT) models in a database containing QLQ-C30 data from 10,815 European cancer patients. (2) Interviews with 41 palliative care patients and 66 professionals in six countries to determine which topics were most appropriate, relevant and important.
Results: Three multi-item scales were shortened without significant loss of precision or measurement power. Results can still be directly compared to the original QLQ-C30 scales. Based on interviews, additional items were removed. The resulting 15-item EORTC questionnaire covers pain, physical and emotional function, fatigue, nausea and vomiting, lack of appetite, dyspnoea, constipation, sleep difficulties, and overall quality of life.
Discussion: The short EORTC core questionnaire for palliative care includes the physical and psychological symptoms of the EORTC QLQ-C30 judged most relevant and important and is more appropriate for palliative care. Results based on the short version can be compared to the many studies using the QLQ-C30.