A systematic review and meta-regression of studies eliciting willingness-to-pay per quality-adjusted life year in the general population

ABSTRACT

Objectives

From the demand-side perspective, the monetary value of one additional quality-adjusted life year (QALY) is estimated as willingness-to-pay per QALY (WTPQ). This study aims to summarize the methods and contexts of elicitation of willingness-to-pay per quality-adjusted life year (WTPQ) in the general population and to investigate the heterogeneity of WTPQ estimates.

Methods

Meta-regression analysis was conducted using Comprehensive Meta-Analysis Software. Sensitivity analyses were undertaken by replacing the lowest and highest 5% and 2.5% of WTPQ by percentiles.

Results

33 studies with 102 WTPQ estimates were included. The overall mean and median WTPQ estimates are $1,280,002 and $44,072, respectively. The meta-regressions demonstrated that types of health gain (quality of life or life length) and certainty of health outcomes are statistically significant factors. Furthermore, compared with online interviews, face-to-face interviews tend to yield lower WTPQ. Moreover, the declining trend of QALY gains and positive effect with statistical significance of the sample age were also noticed.

Conclusion

For valid and representative values of WTPQ, future researchers should therefore take into consideration various scenarios and investigate both health gain with certainty and uncertainty, health gain from both life length and quality of life, and different size of QALY gains.

KEYWORDS:

• Willingness-to-pay
• quality-adjusted life year
• threshold
• cost-effectiveness analysis
• systematic review
• meta-regression

Author contributions

All authors conceived the study design, applied for the grant and assisted in study protocol development and implementation. ZY, JM, FL, CW and YZ reviewed the studies and extracted data. ZY, JM and LS led on the data analysis and wrote the manuscript.

Declaration of interest

Lihua Sun received the Research Project of Liaoning Province Education Department under Grant (2019WZD01). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Supplementary Material

Supplemental data for this article can be accessed here.

Notes

1. QALY as well as health gain variables were included in the multivariate regression even though they were found as insignificant factors by univariate regression.

2. Some studies reported household net income or household income with or without mentioning household size, whereas some just stated income data without referring to which income data they were talking about.

3. Other forms of bias include hypothetical bias and bias due to the form of the payment question (e.g. open-ended versus dichotomous choice).

Additional information

Funding

This work was supported by the Research Project of Liaoning Province Education Department under Grant (2019WZD01). The funders of the study had no role in study design, data collection, data analysis, data interpretation, writing of the manuscript, or publication of this article.