The contribution of work and non-work factors to the onset of psychological distress: an eight-year prospective study of a representative sample of employees in Canada.

OBJECTIVES This study examined how occupation and work organization conditions contributed, over 8 yr, to the onset of psychological distress after adjusting for non-work and individual characteristics. METHODS The data came from the five cycles (Cycle 1=1994-1995, Cycle 5=2002-2003) of Statistics Canada's National Population Health Survey. A sample of 5,270 workers nested in 1,122 neighborhoods and aged 15 to 55 yr with no psychological distress at baseline was analyzed with discrete time survival multilevel regression models. RESULTS The onset of psychological distress decreased over time. Occupation was not significant, whereas social support at work decreased the risk. Substantial effects for non-work and individual factors were found, including neighborhood, social support outside the workplace, demographics, physical health, personality traits, and life habits. CONCLUSIONS This study found that work characteristics made a limited contribution to the onset of psychological distress, but social support in the workplace clearly proved to be an important protective factor. Enterprises must pay special attention to how colleagues and supervisors act to help workers complete tasks.