title: Differential associations of job control components with both waist circumference and body mass index.
abstract: BACKGROUND
  The Job Demand-Control-Support (JDCS) model is commonly used to investigate associations between psychosocial work factors and employee health, yet research considering obesity using the JDCS model remains inconclusive.
  
  
  OBJECTIVE
  This study investigates which parts of the JDCS model are associated with measures of obesity and provides a comparison between waist circumference (higher values imply central obesity) and body mass index (BMI, higher values imply overall obesity).
  
  
  METHODS
  Contrary to common practice, in this study the JDCS components are not reduced into composite or global scores. In light of emerging evidence that the two components of job control (skill discretion and decision authority) could have differential associations with related health outcomes, components of the JDCS model were analysed at the subscale level. A cross-sectional design with a South Australian cohort (N = 450) combined computer-assisted telephone interview data and clinic-measured height, weight and waist circumference.
  
  
  RESULTS
  After controlling for sex, age, household income, work hours and job nature (blue vs. white-collar), the two components of job control were the only parts of the JDCS model to hold significant associations with measures of obesity. Notably, the associations between skill discretion and waist circumference (b = -.502, p = .001), and skill discretion and BMI (b = -.163, p = .005) were negative. Conversely, the association between decision authority and waist circumference (b = .282, p = .022) was positive.
  
  
  CONCLUSIONS
  These findings are significant since skill discretion and decision authority are typically combined into a composite measure of job control or decision latitude. Our findings suggest skill discretion and decision authority should be treated separately since combining these theoretically distinct components may conceal their differential associations with measures of obesity, masking their individual importance. Psychosocial work factors displayed stronger associations and explained greater variance in waist circumference compared with BMI, and possible reasons for this are discussed.
authors: School of Psychology, University of Adelaide, Australia. Electronic address: christopher.bean@adelaide.edu.au.
authors: Christopher G
authors: CG
authors: Bean
authors: School of Psychology, University of Adelaide, Australia.
authors: Helen R
authors: HR
authors: Winefield
authors: Appleton Institute for Behavioural Science, Central Queensland University, Australia.
authors: Charli
authors: C
authors: Sargent
authors: School of Psychology, Social Work and Social Policy, University of South Australia, Australia.
authors: Amanda D
authors: AD
authors: Hutchinson
mesh_terms: D000328:Adult; D001315:Australia; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D004651:Employment / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008960:Models, Psychological; D009765:Obesity; D016272:Occupational Health; D009790:Occupations; D055105:Waist Circumference / Q000502:physiology; D014937:Work / Q000523:psychology*
keywords: Australia; Decision authority; Job control; Job strain; Obesity; Psychosocial stress; Skill discretion; Work stress