title: Construct validity of SF-6D health state utility values in an employed population.
abstract: BACKGROUND
  Health utility values permit cost utility analysis in workplace health promotion; however, utility measures of working populations have not been validated.
  
  
  OBJECTIVE
  To investigate construct validity of SF-6D health utility in a public service workforce.
  
  
  METHODS
  SF-12v2 Health Survey was administered to 3,408 randomly selected public service employees in Australia in 2010. SF-12 scores were converted to SF-6D health utility values. Associations and correlates of SF-6D with health, socio-demographic and work characteristics [comorbidities, body mass index (BMI), Kessler-10 psychological distress (K10), education, salary, effort-reward imbalance (ERI), absenteeism] were explored. Ceiling effects were analysed. Nationally representative employee SF-6D values from the Household, Income and Labour Dynamics in Australia (HILDA) survey (n = 11,234) were compared. All analyses were stratified by sex.
  
  
  RESULTS
  Mean (SE) age was 45.7 (0.35) males; 44.5 (0.22) females. Females represented 72 % of the sample. Mean (SE) health utility 0.792 (0.004); 0.771 (0.003) was higher in males. SF-6D demonstrated both a significant inverse association (p < 0.01) and negative correlations (female; male) with K10 (r = -0.63; r = -0.66), comorbidity count (r = -0.40; r = -0.33), ERI (r = -0.37; r = -0.34) and absenteeism (p < 0.005, r = -0.25; r = -0.21). Mean (SE) SF-6D in HILDA was 0.792 (0.002); 0.775 (0.003) males; females. Correlates and associations in all samples were similar. The general employed demonstrated a significant inverse association with age and positive association with salary. SF-6D was independent of BMI.
  
  
  CONCLUSIONS
  Psychological distress, comorbidity, effort-reward imbalance and absenteeism are negatively associated with employee health. SF-6D is a valid measure of perceived health states in working populations.
authors.affiliation: Menzies Research Institute Tasmania, University of Tasmania, Medical Science 2 Building, 17 Liverpool St, Private Bag 23, Hobart, TAS, 7000, Australia, siyan.baxter@utas.edu.au.
authors.forename: Siyan
authors.initials: S
authors.lastname: Baxter
authors.forename: Kristy
authors.initials: K
authors.lastname: Sanderson
authors.forename: Alison
authors.initials: A
authors.lastname: Venn
authors.forename: Petr
authors.initials: P
authors.lastname: Otahal
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Palmer
mesh_terms: D000328:Adult; D000368:Aged; D001315:Australia; D015992:Body Mass Index; D004651:Employment; D015444:Exercise; D005191:Family Characteristics; D005260:Female; D015438:Health Behavior; D006304:Health Status; D006305:Health Status Indicators; D006306:Health Surveys / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D016272:Occupational Health; D011788:Quality of Life; D011795:Surveys and Questionnaires