Cognitive debriefing and the validity of the Malay EQ-5D-3L in transfusion-dependent thalassemia patients from Sabah, Malaysia

Divergences in health-related quality of life (HRQOL) questionnaire responses may be attributed to multi-ethnic variation. Objective: The aim of this research is to examine the construct validity of the EQ-5D-3L in the context of Sabah, with Kadazan-Dusun constituting the preponderance of transfusion-dependent thalassemia (TDT) cases. Method: Independently or with the help of their careers, TDT patients who had received iron chelators answered a series of questionnaires. Along with the established group validity, test-retest reliability and correlations between HRQOL instruments were ascertained. Results: The study included 332 patients in all, 173 of whom completed the reliability analysis. EQ-5D-3L clarity and comprehension were observed in the majority of patients. The EQ-5D-3L is moderately correlated with the SF-36 and PedsQL. Reliability across domains is moderate to strong, with proxy reporting outperforming self-reporting. Conclusion: The results provide preliminary evidence of the reliability and validity of the EQ-5D-3L in Sabah population.