Employing Psychological Distance to Explain Perspective-Specific EQ-5D-Y-3L Health State Valuation: A Bayesian...

The EQ-5D-Y-3L is a widely used instrument for valuing health states in pediatric populations. Previous studies have shown that composite time tradeoff (cTTO) utilities tend to be higher when adults value health states from a 10-year-old child's perspective than from their own. In this study, we applied construal level theory (CLT) to examine whether variations in psychological distance can explain these differences.

We conducted online cTTO interviews with 150 adults in the United Kingdom, valuing 4 health states using perspectives that experimentally combine high and low psychological distance across all 4 dimensions of psychological distance defined in CLT (social, temporal, spatial, and hypothetical). Using a Bayesian hierarchical analysis, we investigated how each dimension influences the mean, variance, and data quality of EQ-5D-Y-3L utilities.

Our results indicate cTTO utilities were higher at greater levels of aggregated psychological distance (β = 0.02, 95% credible interval [CrI] [0.01, 0.03]), while residual variance remained stable. Each dimension of psychological distance showed a unique association with cTTO utilities, with hypothetical (β = 0.05, 95% CrI [0.02, 0.08]) and temporal distance (β = 0.04, 95% CrI [0.01, 0.07]) positively associated and spatial distance (β = -0.03, 95% CrI [-0.06, 0.00]) showing a small negative association with cTTO utilities.

Overall, the utility difference between adult and child perspectives in EQ-5D-Y-3L valuation may partially be explained by psychological distance. Future research could explore ways to minimize or account for psychological distance effects, such as refining the wording of perspective descriptions in valuation tasks, to ensure greater clarity and consistency in responses.JEL Classification: I10.