The EORTC QLQ-C15-PAL questionnaire: validation study for Spanish bone metastases patients

Quality of life (QL) is a key outcome for advanced disease cancer patients. The European Organization for Research and Treatment of Cancer (EORTC) has developed the QLQ-C15-PAL questionnaire, a short version of the QLQ-C30 for palliative care. The aim of the present study is to validate the QLQ-C15-PAL for use with Spanish patients with bone metastasis.

For this study, we used a consecutive sample of stage IV cancer patients with bone metastases who started radiotherapy with palliative intention. Two assessments were proposed for each patient: one on the first day of treatment and one a month after the end of the radiotherapy sessions. Psychometric evaluation of the structure, reliability, and validity was undertaken.

One hundred and sixteen patients completed the first questionnaire and seventy five completed the second. Multitrait scaling analysis showed that all items met the standards for convergent validity, and all except the fatigue scale met the standards for divergent validity. Cronbach’s coefficient met the 0.7 alpha criterion on all scales except pain (second assessment). Most QLQ-C15-PAL areas had low-to-moderate correlations with the other areas. Significant differences appeared in the comparisons between groups with regard to: patients who died before the second assessment (six areas); patients receiving chemotherapy before starting radiotherapy in the two assessments (three and four areas, respectively); the performance status in the two assessments (nine and eight areas); and the number of RT sessions received (four). Quality of life was better in the second assessment in nine areas.

The QLQ-C15-PAL is a reliable and valid instrument when applied to a sample of Spanish patients. These results are in line with those of other validation studies.