Is Dimension Order Important when Valuing Health States Using Discrete Choice Experiments Including Duration?

Area of Science:

• Health Economics
• Psychometrics
• Preference Measurement

Background:

• Discrete Choice Experiments with Duration (DCE_TTO) are used for preference-based measures like EQ-5D-5L.
• Standard dimension order in self-completion may cause order effects during valuation.
• Investigating the impact of dimension ordering on DCE values is crucial.

Purpose of the Study:

• To examine the importance of health state dimension ordering on Discrete Choice Experiment (DCE) values.
• To assess whether randomizing dimension order affects utility values derived from the EQ-5D-5L.

Main Methods:

• Developed a choice experiment with two health profiles and an immediate death option.
• Conducted a three-arm online study (n=360 per arm) with varying dimension order randomization.
• Employed conditional logit regression and scale parameter testing for model analysis.

Main Results:

• Coefficients were generally consistent across arms, despite minor inconsistencies.
• Arm 3 (randomized within respondents) yielded the widest range of utility values.
• Scale parameter testing indicated models were poolable, suggesting no significant difference.

Conclusions:

• The degree of randomization in DCE health state valuation does not significantly impact values.
• Dimension order appears less critical than other study design factors.
• Findings support the use of standard dimension order in past valuation studies.