Occupational Stress and Depression: Insights from Traditional and Emerging Views

Abstract

This thesis sought to develop the idea that the psychosocial occupational environment contributes to depression risk. The topic of occupational stress and depression was introduced by considering its impact on individual, workplace, economic and societal functioning (Chapter 1). The classic theoretical frameworks utilised to study this relationship were briefly described in Chapter 2 and the demand control/support model (DC/S model; Karasek & Theorell, 1990) was selected to guide the initial analysis. The evidence on the DC/S model and depression risk was subsequently reviewed with a focus on more recent research (Chapter 3). It was deemed that the risk of depression was inconclusive. The review also highlighted a paucity of data from within the Australian workforce. The subsequent three empirical surveys were considered an important contribution to knowledge about occupational stress and depression in the Australian context.

The first empirical study evaluated the DC/S model in a sample of Australian public service employees (Chapter 4). The main effects of control and social support were supported, which prompted interest in advancing knowledge about these specific associations. The social identity approach to stress and wellbeing in the workplace (van Dick & Haslam, 2012) was considered to offer unique insights into these relationships. The perspective was introduced together with an evaluation of the evidence linking social identification to workplace support and mental ill-health (Chapter 5). The chapter provided a solid basis from which to extend expectations for workplace control (Chapter 6). The critical analysis of evidence in these two chapters also raised conceptual and methodological issues within the social identity approach that were addressed in the subsequent studies.

To advance the testing of causal associations Study 2 (Chapter 7) examined predictions with a one-year longitudinal design. Ratings of high demands prospectively predicted depression ratings. The predictions for the main and mediating role of social identification were largely supported with cross-sectional data while longitudinal associations were not significant. Chapter 8 subsequently considered alternate explanations for the contemporaneous associations between social identification, decision latitude and social support, and depression. A final longitudinal study assessed the likelihood that reciprocal associations would best characterise the association between the assessed occupational stressor and depression ratings (Study 3, Chapter 9). The reverse model was found to be the less false account of the data where baseline depression predicted six-month supervisor support and decision authority ratings. The normal causation model was best fitting for the association between social identification and occupational stressors, where social identification at baseline predicted six-month decision authority, co-worker and supervisor support ratings. Only the latter relationships remained significant in the final model. The thesis closed by highlighting the contributions made to evidence, knowledge about occupational stress and depression in Australia, theory, practice and philosophy, with suggestions for future research considered throughout (Chapter 10).