Objectives: The aim of this qualitative study was to investigate how members of the general public in Korea interpret the concept of health, and which dimensions of health are most important to them. We also explored their perceptions of the EuroQoL 5-Dimension (EQ-5D), including the EuroQoL visual analogue scale (EQ-VAS). Methods: We conducted face-to-face, in-depth interviews with 20 individuals from the general population, using a semi-structured interview guide. Content analysis was performed with verbatim transcripts and field notes to identify codes and categorize them according to their similarities and associations. Results: In total, 734 different codes were derived and classified into 4 categories. Participants cited the importance of both the mental and physical aspects of health, although they emphasized that the physical aspects appeared to play a larger role in their conceptualization of health. Participants noted that the EQ-5D has the advantage of being composed of 5 dimensions that are simple and contain both physical and mental areas necessary to describe health. However, some of them mentioned the need to add more dimensions of mental health and social health. Participants showed great satisfaction with the visually well-presented EQ-VAS. However, participants opined that the EQ-VAS scores might not be comparable across respondents because of different ways of responding to the scale. Conclusions While physical health is a fundamental aspect of health, mental and social aspects are also important to Koreans. The content of the EQ-5D broadly matched the attributes of health considered important by Koreans.

INTRODUCTION: Although the EQ-5D questionnaire is widely used to measure health status internationally, there is little evidence of its content validity in Asian populations. This qualitative study aimed to explore the content validity of the EQ-5D in Singapore. MATERIALS AND METHODS: Sixty Singaporeans (Chinese: 20; Malay: 20; Indian: 20) completed semi-structured interviews in which they were asked about health concepts which were important to them and the relevance and comprehensiveness of the EQ-5D descriptive system (DS). Thematic analysis employing open, focused and axial coding was used to identify the themes and subthemes from the interviews. RESULTS: A total of 70 health concepts were identified which fall into the broad categories of 'physical health', 'mental well-being', 'social relationships', 'medical conditions and treatment', and 'health promotion knowledge and behaviours'. The 5 dimensions in the EQ-5D DS were among the health concepts nominated by participants. Some participants suggested that content validity could be improved by adding social relationships, medical conditions and treatment, and health promotion knowledge and behaviours to the EQ-5D DS. CONCLUSIONS This study confirmed that EQ-5D dimensions are important and relevant aspects of health to Asians in Singapore, although some dimensions that could be important to Singaporeans are absent.