title: Comparability of patient-reported health status: multicountry analysis of EQ-5D responses in patients with type 2 diabetes.
abstract: BACKGROUND
  Valid and comparable measures of health outcomes are needed for clinical trials, studies on quality of healthcare, and population health monitoring.
  
  
  OBJECTIVE
  To examine comparability of patient-reported health status across populations.
  
  
  METHODS
  Logistic regression analysis of health status across regions, controlling for demographics, risk factors, and clinical event history.
  
  
  METHODS
  Multicenter clinical trial in 20 countries, grouped into 3 regions defined by geography and levels of economic development (Asia, Established Market Economies, Eastern Europe).
  
  
  METHODS
  11,140 people with type 2 diabetes.
  
  
  METHODS
  Patient-reported health status in 5 domains (mobility, self-care, usual activities, pain/discomfort, anxiety/depression) using EQ-5D.
  
  
  RESULTS
  Examining unadjusted response probabilities, patients in Eastern Europe were consistently more likely than patients in other regions to report problems in all domains. Compared to Asia, probabilities of reporting problems at baseline in Eastern Europe were more than 3 times higher for mobility or usual activities, and more than 6 times higher for self-care. Patients in Asia were less likely than patients in Established Market Economies to report problems in all domains except anxiety/depression. Substantial regional reporting differences persisted after controlling for demographics, common risk factors, and history of major disease complications. Compared to Established Market Economies, adjusted odds ratios for reporting problems in at least 1 health domain were 1.79 (1.55 to 2.06) in Eastern Europe and 0.76 (0.67 to 0.86) in Asia.
  
  
  CONCLUSIONS
  There is substantial variation across regions in reporting on functional health problems, which cannot be explained by differences in demographic variables, clinical risk factors, or rates of complications. This suggests that commonly used health status instruments may have important problems in comparability across settings.
authors.affiliation: Department of Global Health and Population, Harvard School of Public Health, Boston, MA 02115, USA. jsalomon@hsph.harvard.edu
authors.forename: Joshua A
authors.initials: JA
authors.lastname: Salomon
authors.forename: Anushka
authors.initials: A
authors.lastname: Patel
authors.forename: Bruce
authors.initials: B
authors.lastname: Neal
authors.forename: Paul
authors.initials: P
authors.lastname: Glasziou
authors.forename: Diederick E
authors.initials: DE
authors.lastname: Grobbee
authors.forename: John
authors.initials: J
authors.lastname: Chalmers
authors.forename: Philip M
authors.initials: PM
authors.lastname: Clarke
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D001007:Anxiety / Q000453:epidemiology; D001208:Asia; D003863:Depression / Q000453:epidemiology; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology / Q000523:psychology; D005061:Europe, Eastern; D005260:Female; D006304:Health Status; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D051346:Mobility Limitation; D010146:Pain / Q000453:epidemiology; D010147:Pain Measurement; D012307:Risk Factors; D012648:Self Care; D012650:Self Disclosure; D011795:Surveys and Questionnaires / Q000592:standards