title: Psychometric properties of the EQ-5D-5L in Thai patients with chronic diseases.
abstract: OBJECTIVE
  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.
authors.affiliation: Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand. Phantipa.S@pharm.chula.ac.th.
authors.forename: Phantipa
authors.initials: P
authors.lastname: Sakthong
authors.affiliation: Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand.
authors.forename: Nontapat
authors.initials: N
authors.lastname: Sonsa-Ardjit
authors.affiliation: Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand.
authors.forename: Pattarin
authors.initials: P
authors.lastname: Sukarnjanaset
authors.affiliation: Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand.
authors.forename: Wipaporn
authors.initials: W
authors.lastname: Munpan
mesh_terms: D000328:Adult; D044466:Asian People; D002908:Chronic Disease; D015897:Comorbidity; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D010147:Pain Measurement / Q000379:methods; D011594:Psychometrics / Q000295:instrumentation / Q000379:methods*; D011788:Quality of Life / Q000523:psychology*; D011795:Surveys and Questionnaires / Q000592:standards*
keywords: EQ-5D-5L; Psychometrics; Reliability; Responsiveness; Thailand; Validity