Quality of life assessment in patients with nonmelanoma skin cancer – psychometric validation of the EORTC QLQ-C30 questionnaire

Summary

Background

Nonmelanoma skin cancer (NMSC) is a chronic and sometimes difficult-to-treat condition affecting the quality of life (QL). The present study was conducted to investigate whether the European Organization for Research and Treatment of Cancer (EORTC) core QL Questionnaire – Cancer (QLQ-C30) is a suitable tool for the assessment of QL in patients with NMSC.

Patients and methods

In order to define the psychometric properties of the questionnaire, the QLQ-C30 and the Dermatology Life Quality Index (DLQI) were handed out to 172 patients of the Department of Dermatology at the University Hospital Regensburg, Germany.

Results

Internal consistencies of all multi-item scales (except one) were acceptable, with Cronbach's alpha ranging from 0.71 to 0.93. The hypothesized scale structure was supported by item/scale and interscale correlations within the QLQ-C30. Related scales of the QLQ-C30 and the DLQI correlated significantly, thus establishing construct validity. At the same time, the proportion of substantial correlations (6 % ≥ 0.40) indicated that the two questionnaires assessed distinct components of QL. The QLQ-C30 significantly differentiated between clinically distinct patient groups, indicating that severe clinical conditions were associated with greater impairment in physical, role, and cognitive functioning (p ≤ 0.030).

Conclusions

These results confirm the QLQ-C30 to be a suitable tool for the assessment of QL in patients with NMSC.