Methodology for measuring health-state preferences--II: Scaling methods

Area of Science:

• Health economics
• Psychometrics
• Decision analysis

Background:

• Accurate measurement of health-state preferences is crucial for health policy and economic evaluations.
• Various scaling methods exist, but their reliability, validity, and feasibility require systematic evaluation.

Purpose of the Study:

• To describe and evaluate six distinct methods for measuring health-state preferences.
• To compare these methods based on reliability, validity, and feasibility.

Main Methods:

• The study describes and analyzes six scaling methods: standard gamble, time trade-off, rating scale, magnitude estimation, equivalence, and willingness-to-pay.
• Evaluation criteria included reliability (consistency of measurements), validity (accuracy in measuring preferences), and feasibility (ease of administration).

Main Results:

• Most methods demonstrated acceptable reliability for single measurements, but lower reliability over a year suggests preference changes.
• Convergent validity was inconsistently supported across studies.
• The category ratings method showed ease of administration and valid scale values, making it suitable for large samples.

Conclusions:

• Category ratings method is recommended for large-scale health preference studies due to its ease of use and validity.
• Time trade-off and standard gamble methods are more effective for individual decision-making and smaller research projects.