Health state utilities in non-small cell lung cancer: An international study

Quality of life weights (utilities) are an important input in economic evaluation and evidence suggests that there can be important differences between countries. This study was designed to capture utilities for metastatic non-small cell lung cancer and common grade III/IV toxicities associated with treatment from local populations in the United Kingdom, Australia, France, China, Taiwan, and Korea. Toxicities included neutropenia, febrile neutropenia, fatigue, diarrhea, nausea and vomiting, rash, bleeding, hypertension, and hair loss.

Existing health state descriptions of non-small cell lung cancer were adapted to represent descriptions of patients on first-line treatment. Twenty-three states were translated and assessed in cognitive debrief content validation interviews with oncologists in each country. Seventy-five respondents per country completed a time trade-off interview to evaluate the states. Variation between countries for all states was explored with a Generalized Estimating Equations model.

The mean utility for "stable disease and no side effects" (base state) varied between 0.84 (United Kingdom) and 0.54 (Taiwan). The largest utility decrements were found for febrile neutropenia (0.47) and neutropenia (0.35) across all countries. Asian countries regarded bleeds as a severe toxicity whereas non-Asian countries did not and valued diarrhea and fatigue as more severe. Significant differences in utilities between countries emerged with the Taiwanese population in particular rating states as significantly worse than other countries.

This study improves our understanding of how utilities for the same states can vary across countries. The study shows the importance of capturing utilities that reflect the preferences of the local population.