Psychometric performance assessment of Malay and Malaysian English version of EQ-5D-5L in the Malaysian population.

Purpose: To determine the psychometric properties and performance of Malay and English versions of the EQ-5D-5L descriptive instrument in the general Malaysian population.

Methods: 1137 members of the Malaysian general public were sampled in this national study. Respondents were recruited by quota sampling of urbanicity, gender, age, and ethnicity. In face-to-face interviews, respondents first answered the EQ-5D-5L questionnaire administered using the EQ-Valuation Technology software, and then completed the EQ-5D-3L questionnaire on paper. A subgroup of the respondents were given paper form of EQ-5D-5L for completion within 2 weeks for test-retest reliability. Ceiling effects, response redistribution, informativity, and convergent validity were compared between EQ-5D-5L and ED-5D-3L separately by Malay and English language versions.

Results: The proportion of 'full health' responses (11111) drastically decreased by 25.55% and 15.74% in the Malay and English language versions indicating lower ceiling effects in EQ-5D-5L. Inconsistencies from response redistribution was below 6% for all dimensions across languages. The measure of relative informativity was comparatively higher in EQ-5D-5L than in EQ-5D-3L in both language versions, with the exception of dimensions mobility and pain/discomfort in the English version. Convergent validity in terms of correlation with EQ-VAS was relatively better for EQ-5D-5L dimensions, with pain/discomfort of the Malay version having the strongest correlation (|r| = 0.37). Also, reliability testing revealed moderate to poor agreements on all 5L dimensions.

Conclusions: EQ-5D-5L fared better in terms of psychometric performance compared to EQ-5D-3L for both language versions. This encourages the application of the EQ-5D-5L in health-related research in Malaysia.