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

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.