Andrew Bottomley

Introduction: Many health economic evaluations rely on the validity of the utility measurement for health-related quality of life (HRQoL). While generic utility measures perform well in HRQoL assessments of many diseases and patient populations, appropriateness for cancer-specific disease burdens needs attention and condition-specific measures could be a viable option. This study assessed the clinical validity of the cancer-specific EORTC QLU-C10D, a utility scoring algorithm for the EORTC QLQ-C30, in patients with glioblastoma. We expect the EORTC QLU-C10D to be sensitive and responsive in glioblastoma patients. Furthermore, we compared its statistical efficiency with the generic utility measure EQ-5D-3L. Methods: We used data from a multi-center randomized controlled trial (NCT00689221) with patients from 146 study sites in 25 countries. Both, the QLQ-C30 and the EQ-5D-3L, had been administered at seven assessment points together. Utilities of both measures were calculated for four country value set (Australia, Canada, UK, USA). Ceiling effects, agreement (Bland–Altman plots (BA), intra-class correlation (ICC)), were calculated to analyze construct validity. Sensitivity to known-groups (performance status; global health) and responsiveness to changes (progressive vs. non-progressive; stable vs. improved or deteriorated HRQoL) were investigated for clinical validity. Relative Efficiency (RE) was calculated to compare statistical efficiency of both utility measures. Results: 435 patients were included at baseline and six subsequent time points (median timeframe 497 days). QLU-C10D country value set showed negligible ceiling effects (< 6.7%) and high agreement with EQ-5D-3L (ICC > 0.750). BA indicated that differences between both utility measures increased with deteriorating health states. While the QLU-C10D was more sensitive to global health groups (RE > 1.2), the EQ-5D-3L was more sensitive to performance status groups (RE < 0.7) than the other utility measure. Statistical efficiency to detect differences between change groups and within HRQoL deterioration group (RE > 1.4) favored QLU-C10D in 18 of 24 (75%) and 20 of 24 (83%) comparisons with the EQ-5D-3L respectively. Responsiveness to overall HRQoL change (RE > 3.4) also favored the QLU-C10D. Conclusion: Our results indicate that the QLU-C10D is a valid utility measure to assess HRQoL in patients with glioblastoma. This facilitates the investigation of HRQoL profiles and utilities in this patient population by administering a single questionnaire, the EORTC QLQ-C30. Efficiency analyses point to higher statistical power of the QLU-C10D compared to the EQ-5D-3L.

We developed a composite symptom score (CSS) representing disease-related symptom burden over time in patients with malignant pleural mesothelioma (MPM). Longitudinal data were collected from an open-label Phase IIB study in which 239 patients completed the validated MD Anderson Symptom Inventory for MPM (MDASI-MPM). A blinded, independent review committee of external patient-reported outcomes experts advised on MDASI-MPM symptoms to include in the CSS. Through iterative analyses of potential symptom-item combinations, 5 MPM symptoms (pain, fatigue, shortness of breath, muscle weakness, coughing) were selected. The CSS correlated strongly with the full MDASI-MPM symptom set (0.92–0.94) and the Lung Cancer Symptom Scale-Mesothelioma (0.79–0.87) at each co-administration of the scales. The CSS also had good sensitivity to worsening disease and global quality-of-life ratings. The MDASI-MPM CSS can be used as an outcome in MPM clinical trials, including in responder analyses and at the individual patient level. It is brief enough to administer frequently, including electronically, to better capture symptom trajectories during and after a trial and in clinical practice. As a single score, the CSS addresses multiplicity issues that can arise when several symptoms increase due to worsening disease. Our process can be adapted to produce a CSS for other advanced-cancer trials.