Promoting mental health in a large and diverse public sector workforce

Background: Worker mental ill-health has significant repercussions for labour productivity and economic growth, health and welfare systems, community functioning and social equity. Comprehensive workplace health promotion is a popular program framework for whole-of-workforce health intervention but little is known of its effectiveness when this initiative is scaled up in size to target the health of every employee in a workforce. Aims: This thesis aimed to examine the promotion of mental health in a state public sector workforce in Tasmania, Australia by: i) assessing the prevalence and correlates of poor mental health, ii) identifying trends, costs and correlates of occupational mental diseases; iii) quantifying the effects of a whole-of-workforce workplace health promotion initiative on individual mental health; and iv) measuring whether exposure to workplace health promotion was associated with reduced job-related stress. Methods: Workforce and population survey data were used to benchmark prevalence and then assess correlates of high psychological distress (Kessler-10) in 2010 (Chapter 3). Occupational diseases and injuries were assessed using deidentified regulatory data provided by WorkCover Tasmania on workers' compensation claims made by Tasmanian Government workers between 2007 and 2012 (Chapter 4). Repeated cross-sectional analyses (2010 and 2013) were used to assess differences in whole-of-workforce psychological distress over time in relation to direct and indirect forms of workplace mental health promotion (Chapter 5). Job stress differences over time as measured by effort-reward imbalance, were also assessed in relation to the availability of and participation in workplace health promotion using repeated cross-sectional analysis (Chapter 6). Results: Men and younger employees had more prevalent high distress than population norms (Chapter 3). Differences in distress prevalence were observed based on whether data were collected by researchers or the employer. Job stress, as measured by high effort reward imbalance was a key correlate of high distress for men and women (Chapter 3). Trends and costs of stress claims were stable over time, however short-comings in job-stress compensation legislation and regulatory data were identified (Chapter 4). Participation in programs indirectly targeting mental health was positively associated with women's psychological distress, however increased exposure to workplace health promotion did not effect the observed difference in women's Kessler-10 scores over 3-years (Chapter 5). When results were examined over time, statistical interactions were identified between higher availability of WHP and lower ERI scores for women. Nevertheless, effect modifications were modest for this group and their mean job stress was not statistically lower after 3 years (Chapter 6). Conclusions: Mental health promotion in Australian workplaces is entering a new phase of evolution due to the introduction of work health and safety legislation that places the onus on employers to monitor and intervene for work-related hazards. These changes highlight the need for, and importance of routine data collection on employee mental health. Better brief surveillance measures and compensation claim data are needed if employers are to meet this challenge. Comprehensive workplace health promotion may offer benefits for mental health and job stress in public sector workforces. However further naturalistic studies examining organisational context and program quality alongside this intervention need to be conducted to clarify the nature of the relationships observed here.