The EORTC QLU-C10D is a valid cancer-specific preference-based measure for cost-utility and health technology assessment in the Netherlands

Assessing the reliability of a novel cancer-specific multi-attribute utility instrument (FACT-8D) and comparing its validity to EQ-5D-5L in colorectal cancer patients

OBJECTIVE

To examine the test-retest reliability of the Functional Assessment of Cancer Therapy - 8 Dimension (FACT-8D) for the first time, and to conduct a head-to-head comparison of the distribution properties and validity between the FACT-8D and EQ-5D-5L in Colorectal Cancer (CRC) Patients.

METHODS

We conducted a longitudinal study on Chinese CRC patients, employing Functional Assessment of Cancer Therapy-General (FACT-G) and EQ-5D-5L at baseline, and FACT-G during follow-up (2-7 days from baseline). Utility scores for FACT-8D were derived from all available value sets (Australia, Canada and USA), while EQ-5D-5L scores were obtained from corresponding value sets for various countries. We assessed convergent validity using pairwise polychoric correlations between the FACT-8D and EQ-5D-5L; known-groups validity by discriminating participants' clinical characteristics, and effect size (ES) was tested; test-retest reliability for FACT-8D using kappa and weighted Kappa for choice consistency, and intraclass correlation coefficient (ICC) and Bland-Altman method for utility consistency.

RESULTS

Among the 287 patients with CRC at baseline, 131 were included in the retest analysis. The utility scores of FACT-8D were highly positively correlated with EQ-5D-5L across various country value sets (r = 0.65-0.77), and most of the dimensions of FACT-8D and EQ-5D-5L were positively correlated. EQ-5D-5L failed to discriminate known-groups in cancer stage across all value sets, whereas both were significant in FACT-8D (ES = 0.35-0.48, ES = 0.38-0.52). FACT-8D showed good test-retest reliability (Cohen's weighted Kappa = 0.494-0.722, ICC = 0.748-0.786).

CONCLUSION

The FACT-8D can be used as a valid and reliable instrument for clinical evaluation of patients with CRC, outperforming EQ-5D-5L in differentiating clinical subgroups and showing promise for cancer practice and research.

Valuing quality of life for economic evaluations in cancer: navigating multiple methods

INTRODUCTION

Utility values offer a quantitative means to evaluate the impact of novel cancer treatments on patients' quality of life (QoL). However, the multiple methods available for valuing QoL present challenges in selecting the most appropriate method across different contexts.

AREAS COVERED

This review provides cancer clinicians and researchers with an overview of methods to value QoL for economic evaluations, including standalone and derived preference-based measures (PBMs) and direct preference elicitation methods. Recent developments are described, including the comparative performance of cancer-specific PBMs versus generic PBMs, measurement of outcomes beyond health-related QoL, and increased use of discrete choice experiments to elicit preferences. Recommendations and considerations are provided to guide the choice of method for cancer research.

EXPERT OPINION

We foresee continued adoption of the QLU-C10D and FACT-8D in cancer clinical trials given the extensive use of the EORTC QLQ-C30 and FACT-G in cancer research. While these cancer-specific PBMs offer the convenience of eliciting utility values without needing a standalone PBM, researchers should consider potential limitations if they intend to substitute them for generic PBMs. As the field advances, there is a greater need for consensus on the approach to selection and integration of various methods in cancer clinical trials.

Cancer-Specific Health Utilities: Evaluation of Core Measurement Properties of the EORTC QLU-C10D in Lung Cancer Patients-Data from Four Multicentre LUX-Lung Trials, Applying Six Country Tariffs

BACKGROUND

Cost-utility analysis generally requires valid preference-based measures (PBMs) to assess the utility of patient health. While generic PBMs are widely used, disease-specific PBMs may capture additional aspects of health relevant for certain patient populations. This study investigates the construct and concurrent criterion validity of the cancer-specific European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Utility-Core 10 dimensions (QLU-C10D) in non-small-cell lung cancer patients.

METHODS

We retrospectively analysed data from four multicentre LUX-Lung trials, all of which had administered the EORTC Quality of Life Questionnaire (QLQ-C30) and the EQ-5D-3L. We applied six country-specific value sets (Australia, Canada, Italy, the Netherlands, Poland, and the United Kingdom) to both instruments. Criterion validity was assessed via correlations between the instruments' utility scores. Correlations of divergent and convergent domains and Bland-Altman plots investigated construct validity. Floor and ceiling effects were assessed.

RESULTS

The comparison of the EORTC QLU-C10D and EQ-5D-3L produced homogenous results for five of the six country tariffs. High correlations of utilities (r > 0.7) were found for all country tariffs except for the Netherlands. Moderate to high correlations of converging domain pairs (r from 0.472 to 0.718) were found with few exceptions, such as the Social Functioning-Usual Activities domain pair (max. r = 0.376). For all but the Dutch tariff, the EORTC QLU-C10D produced consistently lower utility values compared to the EQ-5D-3L (x̄ difference from - 0.082 to 0.033). Floor and ceiling effects were consistently lower for the EORTC QLU-C10D (max. 4.67% for utilities).

CONCLUSIONS

The six country tariffs showed good psychometric properties for the EORTC QLU-C10D in lung cancer patients. Criterion and construct validity was established. The QLU-C10D showed superior measurement precision towards the upper and lower end of the scale compared to the EQ-5D-3L, which is important when cost-utility analysis seeks to measure health change across the severity spectrum.