The contingent valuation method in health care

Area of Science:

• Health Economics
• Health Technology Assessment
• Survey Methodology

Background:

• The contingent valuation method (CVM) is a survey-based approach to assign monetary values to health technology benefits.
• Willingness to pay (WTP) is a key metric in CVM, often compared to other benefit measures in medical technology assessment.
• Existing literature reviews highlight significant methodological and conceptual challenges associated with CVM in healthcare.

Purpose of the Study:

• To comprehensively review the methodological and conceptual issues of the contingent valuation method (CVM) in the health care literature.
• To assess the validity and reliability of CVM as a tool for determining monetary valuations of health technology effects.
• To identify areas for further research to improve the application of CVM in healthcare decision-making.

Main Methods:

• Systematic review of studies published before 1998, identified through computerized databases and previous reviews.
• Inclusion criteria focused on studies using original data and meeting qualitative standards for CVM application.
• Analysis of methodological aspects including elicitation formats, validity (theoretical, convergent, criterion), reliability, and potential biases (starting point, range, strategic).

Main Results:

• CVM demonstrated sufficient theoretical validity and indications of convergent validity, but criterion validity and reliability remain under-investigated.
• Widespread use of diverse elicitation formats complicates study comparisons; direct questions and starting point bias in bidding games were identified as problematic.
• Range bias in payment cards was suggested, but no strategic bias was found. Limited investigation into valuation states and payment methods.
• Influence of valuation states (ex-ante, ex-post) and respondent status (diseased/non-diseased) requires further study.

Conclusions:

• While CVM shows theoretical promise for valuing health technologies, significant methodological and conceptual issues require further investigation.
• Addressing elicitation biases, improving reliability testing, and exploring valuation states are crucial before CVM can be reliably used in healthcare decision-making.
• Further research should focus on criterion validity, reliability assessments, and understanding the impact of different evaluation contexts and respondent characteristics.