Validation of the cancer-specific utility measure EORTC QLU-C10D using evidence from four lung cancer trials covering six country value sets

The Quality of Life (QoL) Utility measure, QLU-C10D, is derived of the European Organisation for Research and Treatment of Cancer (EORTC) QoL Questionnaire, QLQ-C30. Based on the cancer-specific nature, the QLU-C10D is expected to be sensitive and responsive in lung cancer patients.This retrospective analysis used data from four international lung cancer multi-center trials (NCT00656136, NCT00949650, NCT01085136, NCT01523587). Clinical validity was assessed in comparison to a generic standard utility instrument, the EuroQoL Group´s EQ-5D-3L. Utilities of six country value sets (Australia, Canada, Italy, the Netherlands, Poland, UK) were calculated at baseline and end of treatment for both measures. Country value set pairs of both measures (k) were compared in terms of Relative Efficiency (RE) and difference in Effect Sizes (dES) in 1) sensitivity to detect differences between performance status groups and 2) responsiveness to changes at each trial sample. Analysis of the four trials (N1 = 496, N2 = 290, N3 = 202, N4 = 770) with the six country value sets of each utility measure showed ad 1) Sensitivity indices favored the QLU-C10D (k = 18, p ≤ 0.019; RE > 1.10; dES > 0.03), and ad 2) Responsiveness indices of changes within clinically known groups (k = 78), largely favored QLU-C10D (k = 74, p ≤ .024; RE > 1.01; dES > 0.02), in comparison with the generic utility instrument. In summary, 96% of the comparative indices favored the QLU-C10D. In summary, this study confirms the clinical validity of the QLU-C10D in lung cancer patients. The QLU-C10D produced homogenous results across six country value sets and detected differences/changes in alignment with clinical expectations. In most comparisons the QLU-C10D was more sensitive or responsive compared to the EQ-5D-3L.