Objectives: To estimate the current prevalence of major depression in a sample of working population, and to examine the associations between job strain, effort-reward imbalance and family-work conflicts and major depression.
Methods: A sample of employees who were between the ages of 25 and 65 years and who were working in Alberta at the time of survey was recruited using the method of random digit dialing (n = 4,302). Data about job stress, effort-reward imbalance and work-family conflicts and depression were collected via telephone. Depression was assessed by the Patient Health Questionnaire (PHQ-9) for depression.
Results: The 2-week prevalence of major depression based on the DSM algorithm was 3.2%. The prevalence of severe depression was 0.8%. Job strain, effort-reward imbalance and work-family conflicts were strongly associated with continuous depression score. Effort-reward imbalance was significantly associated with depression scores in women, but not in men. Effort-reward imbalance was significantly associated with depression scores in participants with job strain ratio >1, but not in those with a lower job strain ratio. The association between work to family conflict and depression score was stronger in participants with a job strain ratio greater than one than in those whose job strain ratio was one or less.
Conclusions: The three job-related stress models are widely used in occupational health research. They are equally important in predicting depression and interact with each other. Improving work environment based on these models holds potentials to reduce the synergetic effects, therefore, improving employees' mental health.