title: Do changes in job control predict differences in health status? Results from a longitudinal national survey of Canadians.
abstract: OBJECTIVE
  To examine the effect of changes in job control on health behaviors, psychological distress and health status.
  
  
  METHODS
  Using a path analysis model, we examined the effects of change in job control over a 4-year period on levels of physical activity, smoking, and psychological distress; and on self-rated health over an additional 2 years, among a representative sample of 2221 Canadians.
  
  
  RESULTS
  Over the 4-year period, 280 respondents reported decreases in job control, and 256 reported increases in job control. Health at baseline was not associated with the likelihood of changes in job control. We found a graded relationship between change in job control and levels of physical activity and psychological distress over a 4-year period; and levels of self-rated health over a 6-year period, with positive change in job control associated in higher levels of physical activity and self-rated health and lower levels of distress.
  
  
  CONCLUSIONS
  The results of this study suggest that both level of job control and changes in job control have direct and indirect effects on health status over time. Future research should focus on developing precise measures of work exposures, and examine differences between changes in job control due to only changes in perceptions and changes due to work redesign.
authors.affiliation: Institute for Work and Health, 481 University Avenue, Suite 800, Toronto, ON, Canada M5G 2E9. psmith@iwh.on.ca
authors.forename: Peter
authors.initials: P
authors.lastname: Smith
authors.forename: John
authors.initials: J
authors.lastname: Frank
authors.forename: Susan
authors.initials: S
authors.lastname: Bondy
authors.forename: Cameron
authors.initials: C
authors.lastname: Mustard
mesh_terms: D000328:Adult; D002170:Canada; D002322:Career Mobility; D003625:Data Collection; D005260:Female; D015438:Health Behavior; D006304:Health Status; D006801:Humans; D007389:Internal-External Control; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D013315:Stress, Psychological