The ability of cancer-specific and generic preference-based instruments to discriminate across clinical and self-reported measures of cancer severities

Abstract

ObjectiveTo evaluate the validity of cancer-specific and generic preference-based instruments to discriminate across different measures of cancer severities.MethodsPatients with breast (n = 66), colorectal (n = 57), and lung (n = 61) cancer completed the EORTC QLQ-C30 and the FACT-G, as well as three generic instruments: the EQ-5D, the SF-6D, and the HUI2/3. Disease severity was quantified using cancer stage, Eastern Cooperative Oncology Group Performance Status (ECOG-PS) score, and self-reported health status. Comparative analyses confirmed the multi-dimensional conceptualization of the instruments in terms of construct and convergent validity.ResultsIn general, the instruments were able to discriminate across severity measures. The instruments demonstrated moderate to strong correlation with each other (r = 0.37-0.73). Not all of the measures could discriminate between different groups of disease severity: the EQ-5D and SF-6D were less discriminative than the HUI2/3 and the cancer-specific instruments.ConclusionThe cancer-specific and generic preference-based instruments demonstrated to be valid in discriminating across levels of ECOG-PS scores and self-reported health states. However, the usefulness of the generic instruments may be limited if they are not able to detect small changes in health status within cancer patients. This raises concerns regarding the appropriateness of these instruments when comparing different cancer treatments within an economic evaluation framework.

QLU-C10D: a health state classification system for a multi-attribute utility measure based on the EORTC QLQ-C30

“…Eighteen suitable datasets were obtained [27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44]. Table 1 summarises their characteristics and the number of observations each contributed to various psychometric analyses.…”

Predicting utility scores for prostate cancer: mapping the Prostate Cancer Index to the Patient-Oriented Prostate Utility Scale (PORPUS)

“…38,39 Generic utility instruments, such as the EQ-5D, lack coverage of the unique content of many disease-specific measures 40 and may not be responsive to change. 18, 19 The Health Utilities Index, EQ-5D, and Quality of Well-being Scale have no questions related to sexual function, and only the Quality of Well-being Scale asks about urinary control or bowel function. These generic utility instruments were less responsive to post-treatment changes in newly diagnosed PC patients than PORPUS utilities.…”

“…Although the Health Utilities Index, 14,15 EQ-5D 16 and SF-6D 17 are among the most common target instruments for utility mapping, 12 there is evidence that generic instruments are not as responsive as disease-specific instruments in detecting changes and differences between clinical groups of cancer patients. 18,19 Therefore, we developed the Patient-Oriented Prostate Utility Scale (PORPUS-U) 20 (Appendix 2) to obtain utilities for PC. The PORPUS has been administered to PC patients in clinical studies 18,21,22 and a clinic database, 23,24 but the PCI has been administered more widely, including to patients in the CaPSURE database.…”

Quality of Life Improvement in Patients Treated with Degarelix versus Leuprorelin for Advanced Prostate Cancer

“…Generic instruments are less responsive for detecting changes and differences among clinical groups of patients with cancer. 29 Utility estimates differed depending on the mapping algorithm used. For almost all outcomes results using the algorithm of McKenzie and van der Pol 14 were lower than those of the other 2 methods using EORTC QLQ-C30 data.…”