Population norms for the EQ-5D-3L and EQ-5D-5L in Peninsular Malaysia

Population norms for preference-based health-related quality of life (HRQoL) instruments provide essential reference data for burden-of-disease assessments, economic evaluations, and quality-adjusted life year (QALY) calculations. Although Malaysian EQ-5D value sets are available, population norms have not been established. This study aimed to establish the first population norms for the EQ-5D-3L and EQ-5D-5L in Peninsular Malaysia, compare their distributional characteristics, and identify factors associated with HRQoL.

We conducted a cross-sectional study among 1,137 adults aged 18 years or older across eight locations in four regional clusters of Peninsular Malaysia. Quota-based sampling was stratified by urbanicity, sex, age, and ethnicity. Participants completed the EQ-5D-5L, EQ-5D-3L, and EQ visual analogue scale (EQ VAS). We calculated index scores using Malaysian value sets and constructed survey weights using iterative proportional fitting to the 2020 Malaysian census. We estimated population norms overall and by sociodemographic strata. Multivariable regression analyses identified factors independently associated with HRQoL.

The weighted mean EQ-5D-5L index score was 0.919 (SD 0.105), the EQ-5D-3L index score was 0.945 (SD 0.090), and the EQ VAS score was 85.4 (SD 12.5). The ceiling effect was substantially lower for the EQ-5D-5L than for the EQ-5D-3L (44.4% vs. 68.5%), with 96 and 29 unique health profiles observed, respectively. Pain/discomfort and anxiety/depression were the most frequently reported problems. Older age, unemployment, rural residence, and doctor-diagnosed disease were associated with lower HRQoL.

This study provides the first population norms for the EQ-5D-3L and EQ-5D-5L in Peninsular Malaysia. These norms serve as essential reference values for clinical research, economic evaluations, and health policy decision-making.