Deriving New Zealand Population Norms for the EQ-5D-5L Using Individual VALUE SETS

OBJECTIVES

In 2018, a New Zealand (NZ) value set was derived for the EQ-5D-5L using a valuation method not used in this area before. The aims of this study were to construct NZ EQ-5D-5L population norms and to examine the relationship between self-reported health-related quality of life (HRQoL) and sociodemographic characteristics.

METHODS

Utility scores for each participant (n=2468) were calculated using their self-reported EQ-5D-5L health status and individual preference weights. Differences in proportion or mean with respect to age and gender were tested using Chi-squared and Kruskal-Wallis tests. Univariable logistic regression and multivariable Tobit models were used to explore the association between sociodemographic characteristics and self-reported health status, utility values and EQ-VAS scores.

RESULTS

The mean utility and VAS scores were 0.847 and 74.8 respectively. There was evidence of differences in all EQ-5D-5L dimensions, utility and EQ-VAS scores by age and gender. Thirty-seven respondents (1.5%) had a negative utility value and 543 (22%) respondents had a utility value of 1. The most frequently reported health states were 11111 (22.0%), 11121 (13.7%), and 11112 (8.9%). Retirees and people aged ≥45 years had higher odds of having problems across every dimension except for anxiety/depression. People not in paid work or those on a benefit had seven times the odds of having problems with self-care and almost six times the odds of having problems with usual activities than people with full-time jobs. Having a long-term disability, or at least one chronic disease, was associated with problems across all five dimensions. Gender, age, ethnicity, employment, long-term disability and chronic disease were all associated with utility.

CONCLUSIONS

NZ EQ-5D-5L population norms are comparable to those reported in other countries. The results from this study will support health funders and policy makers in making resource allocation decisions and understanding the HRQoL of its population.