EQ-5D-5L value set for Norway: a hybrid model using cTTO and DCE data

Purpose: To develop the Norwegian value set for the EQ-5D-5L based on interviews with a representative sample of the Norwegian adult population. Methods: Random and quota sampling were used to recruit the sample of adults (age> 18 years) representative of the Norwegian general population. Data collection followed EQ-VT 2.1 undertaken before and after the COVID-19 pandemic from November 2019 to December 2022, using PC-assisted and video conferencing interviews, respectively. Each respondent valued 10 health states using composite time trade-off (cTTO) and 7 health states using a discrete choice experiment (DCE). Different statistical models were assessed for logical consistency and predictive accuracy using cTTO and DCE data alone or in combination as hybrid models. Results: Of the 1,321 respondents, 1,237 met inclusion criteria. All statistical models demonstrated logical consistency. The weighted hybrid model combining both cTTOand DCE data was preferred and had the highest predictive accuracy. Predicted values ranged from -0.453 to 1, and the dimension of anxiety/depression was the most highly valued by respondents, followed by pain/discomfort, self-care, mobility, and usual activities. These findings are not dissimilar to those for most Western European countries, and regression coefficients are closest to those for other Scandinavian countries. Conclusion: This study provides the Norwegian value set for the EQ-5D-5L based on health state values obtained from members of the adult general population in Norway. This is an important contribution to economic evaluation and the broader application ofthe EQ-5D-5L in Norway including clinical and health services research, and quality measurement.