Methodology of health-related quality of life analysis in phase III advanced non-small-cell lung cancer clinical trials: a critical review

Background: Health-related quality of life (HRQoL) is recognized as a component endpoint for cancer therapy approvals. The aim of this review was to evaluate the methodology of HRQoL analysis and reporting in phase III clinical trials of first-line chemotherapy in advanced non-small cell lung cancers (NSCLC). Methods: A search in MEDLINE databases identified phase III clinical trials in first-line chemotherapy for advanced NSCLC, published between January 2008 to December 2014. Two authors independently extracted information using predefined data abstraction forms. Results: A total of 55 phase III advanced NSCLC trials were identified. HRQoL was declared as an endpoint in 27 studies (49 %). Among these 27 studies, The EORTC questionnaire Quality of Life Questionnaire C30 was used in 13 (48 %) of the studies and The Functional Assessment of Cancer Therapy-General was used in 12 (44 %) trials. The targeted dimensions of HRQoL, the minimal clinically important difference and the statistical approaches for dealing with missing data were clearly specified in 13 (48.1 %), 9 (33.3 %) and 5 (18.5 %) studies, respectively. The most frequent statistical methods for HRQoL analysis were: the mean change from baseline (33.3 %), the linear mixed model for repeated measures (22.2 %) and time to HRQoL score deterioration (18.5 %). For each targeted dimension, the results for each group, the estimated effect size and its precision were clearly reported in 4 studies (14.8 %), not clearly reported in 11 studies (40.7 %) and not reported at all in 12 studies (44.4 %). Conclusions: This review demonstrated the weakness and the heterogeneity of the measurement, analysis, and reporting of HRQoL in phase III advanced NSCLC trials. Precise and uniform recommendations are needed to compare HRQoL results across publications and to provide understandable messages for patients and clinicians.