Purpose
Due to the problem of high ceiling effects of the EQ-5D-3L, the EQ-5D-5L was developed. However, little was known about the full psychometric properties of the EQ-5D-5L. Thus, this study aimed to evaluate its practicality, reliability, validity, and responsiveness in Thai patients with chronic diseases.
Methods
One thousand one hundred and fifty-six adults taking a medicine at least 3 months were identified from three university hospitals in Bangkok, Thailand, between July 2014 and March 2015. Practicality was evaluated by administration times and ceiling effects. Test–retest reliability was assessed using weighted kappa and intraclass correlation coefficients (ICCs). Validity was tested with correlations between the EQ-5D-5L and WHOQoL-BREF and SF-12v2, and known-groups validity. Responsiveness was measured with standardized effect sizes (SES).
Results
The mean administration time was approximately 2 min, and the ceiling effect of the EQ-5D-5L index was 13.6 %. The weighted kappa values and ICC of the EQ-5D-5L were 0.48–0.61 and 0.82, respectively. Similar dimensions of the EQ-5D-5L had higher correlations with those of WHOQoL-BREF and SF-12v2. As expected, elderly, female, low-educated, unemployed, higher number of comorbidities and medicines, patients’ perception of poor disease control, and having an adverse drug reaction tended to have poorer EQ-5D-5L scores. The SES of EQ-5D-5L index and EQ-VAS were considered small (0.33–0.42) for the improved group. For the worsened group, the SES of the EQ-5D-5L index were considered small (−0.29) but that of the EQ-VAS considered large (−0.82).
Conclusions
The EQ-5D-5L was practical, reliable, valid, and responsive in Thai patients with chronic diseases.