Validity, Reliability, and Framing Effects in Equity-Efficiency Trade-Off Studies: A Systematic Review.

Area of Science:

• Health Economics
• Public Health Policy
• Behavioral Economics

Background:

• Health system resource allocation necessitates balancing equity and efficiency.
• Public values, crucial for guiding these trade-offs, are often elicited through choice experiments.
• Current methods for eliciting equity-efficiency trade-offs lack standardization, leading to concerns about the robustness of findings.

Purpose of the Study:

• To systematically review equity-efficiency trade-off studies.
• To assess the consideration of validity, reliability, and framing effects in these studies.
• To identify methodological challenges for future research on inequity aversion.

Main Methods:

• A systematic search of Medline, EMBASE, and Web of Science was conducted in May 2025.
• Two independent reviewers screened titles, abstracts, and full texts.
• Data extraction and quality assessment were performed on identified studies.

Main Results:

• Out of 122 identified studies, 33% addressed validity, reliability, or framing effects.
• Validity was most commonly assessed against expected outcomes; reliability by repeated testing.
• While most studies reported good validity/reliability, framing effects were less frequently assessed.

Conclusions:

• Methodological rigor in assessing validity, reliability, and framing effects is inconsistent across studies.
• Addressing these methodological challenges is crucial for improving future choice experiments.
• Enhanced study designs can lead to more robust estimations of public values and inequity aversion.