published_or_final_version / Medical Sciences / Master / Master of Medical Sciences

published_or_final_version / Psychiatry / Doctoral / Doctor of Philosophy

This study used a multi-method approach to explore factors associated with high and low depression in a sample of rural mothers living in poverty. From a sample of 117 women with very high or very low CES-D depression scores, 40 cases were randomly selected for in-depth qualitative analysis. Qualitative comments about a variety of issues were explored including health, mental health, childcare, transportation, community, social support, and family of origin experiences. Quantitative data were then used in response to themes that emerged from the literature and the qualitative findings. All 117 eligible participants were used for quantitative analysis to increase power. Analysis of the qualitative data revealed several critical differences between the two groups. Low risk participants mentioned fewer health issues and less severe health problems as compared to their high risk counterparts. Mental health issues were reported more in the high risk group, with this group being more likely to have multiple family members experiencing symptoms. All participants reported receiving social support, however, the low risk group reported positive social support experiences, while the high risk group reported ambivalent relationships with the people who provided them with social support. Reported family of origin experiences were quite different between the two groups, with the low risk group reporting more positive past and current relationships. Quantitatively, several interesting results were revealed, many confirming the qualitative findings. Mothers showing higher levels of depression reported significantly more health problems for themselves, their partners, and their children. Additionally, participant's work status, income, perceived adequacy of income, childhood welfare use, and presence of partner were significantly related to depression. Low risk respondents were more likely to be working, perceive their income as adequate, and have a partner. They were also less likely to have received welfare as a child and had higher incomes. The findings offer important implications for future research and policy. Risk for depression seems to be related to a variety of factors, indicating that something should be done to minimize an individual's likelihood toward experiencing depression. This study ultimately provided a clearer picture of the existence of depressive symptoms among women with children living in rural poverty. / Graduation date: 2003

Traumatic events are a common part of the human experience. Posttraumatic stress disorder (PTSD) and major depressive disorder (MDD) are common sequelae of trauma that are both associated with poor physical health and mortality. The objective of this dissertation is to identify common and unique risk factors for each disorder in order to identify at-risk groups for PTSD and/or depression following trauma. his dissertation is organized into five parts: 1) an introduction, 2) a simulation study exploring the use of test equating methods to standardize the Hospital Anxiety and Depression Scale (HADS) to the Beck Depression Inventory II (BDI) in order to create common depression scale across studies in a pooled analysis, 3) an individual participant data meta-analysis on risk factors for PTSD and depression following incident trauma, 4) a Mendelian Randomization analysis of childhood abuse victimization and neuroticism on PTSD and depression, 5) a discussion of the findings and avenues for future research. The simulation study found that an Equated BDI diagnosis had higher specificity (range: 0.86 to 0.91) compared to using the HADS diagnosis (range: 0.80 to 0.82) when the correlation between the BDI and HADS was greater than 0.7, but had lower sensitivity (Equated BDI range: 0.67 to 0.72; HADS range: 0.84 to 0.92). The Equated BDI diagnosis was found to improve statistical power when the prevalence of depression was 20% or higher with greater improvements when the proportion of studies assessing the depression with the HADS was less than 50%. In the individual participant data meta-analysis, common risk factors for acute and persistent MDD and PTSD were found including increased risk for female sex and reduced risk for those who experienced an accident versus an assault or other traumatic event as the index trauma. Acute MDD symptom severity was associated with persistent PTSD and remained significant after inclusion of acute PTSD symptom severity. In an analysis of PTSD symptom clusters, only reexperiencing symptoms were associated with persistent PTSD along with MDD symptom severity. In models of persistent MDD, acute PTSD symptom severity was associated with persistence, but neither overall symptom severity nor cluster symptom severities were associated with persistence after inclusion of acute MDD symptom severity. In the Mendelian Randomization analysis, childhood abuse victimization was found to be associated with PTSD symptom severity but was not associated with an increased odds of a MDD diagnosis, while neuroticism was associated with an increased odds of a diagnosis of MDD, but was not associated with an increase in PTSD symptom severity. Findings from the meta-analysis that leveraged the use of item-response theory imply that while PTSD and MDD share many risk factors for onset of symptoms following the experience of a traumatic event, persistence of symptoms depends most strongly on initial symptoms. However, PTSD and MDD were also found to have different relationships with childhood abuse victimization and neuroticism, indicating that some risk factors are unique to each disorder. Future studies can build upon these results, especially when pooling data from different studies, to further explicate the associations between PTSD, MDD, and their causes.

Thesis (PhD)--Macquarie University, Faculty of Human Sciences, Department of Psychology, Centre for Emotional Health, 2009. / Includes bibliographical references. / Introduction -- Parenting in adolescent depression: the mediating role of self-worth in a prospective test -- Neuroticism, life events and negative thoughts in the development of depression in adolescent girls -- A cognitive diathesis-stress generation model of early adolescent depression -- General discussion. / This research examined the longitudinal development of depressive symptoms among young adolescents (mean age 12 years). The first model examined depressive symptoms across 6 months in 315 young adolescents and their mothers, considering the mediation of perceived parenting and its influence on adolescent self-worth. Although parent-reported parental depression was not linked with child-reported perceived parenting, the child's perception of his or her mother as rejecting or less caring was associated with a lower sense of self-worth, which in turn predicted depressive symptoms 6 months later, controlling for initial depression. In the second model, tested across 12 months with 896 young adolescent girls, neuroticism served as a distal vulnerability for depression, conferring a risk of experiencing dependent stressors and negative automatic thoughts which fully mediated the effect of neuroticism on later depression. Initial depressive symptoms also followed this meditational pathway, in a possible maintenance and risk pathway for adolescent depression. Unexpectedly, independent stressors were also predicted by initial depressive symptoms, suggesting possible shared method or genuine environmental factors. Finally, it was proposed that young adolescents at risk of depression will not only display cognitive vulnerabilities contributing to increased depressive symptoms following stressors (cognitive diathesis-stress theory), but also be more likely to experience stressors at least partly dependent on their own behaviour (stress-generation theory). This model was supported with a large (N=756) sample of young adolescents across 6 months, controlling for initial depression. Taken together, this thesis extends previous theories about the aetiology of depression, providing evidence from family, personality and cognitive risk factors to better explain the development of depressive symptoms in early adolescence, with significant implications for intervention and treatment. / Mode of access: World Wide Web. / viii, 140 leaves ill

M.Cur. / The birth of a baby is a life-changing event in a person's life. During this time there are expectations of positive feelings. The new mother experience ambivalent feelings about the new phase in her life. These feelings can range from a feeling of excitement, postpartum-tears, anxiety about the baby's care, depression and psychosis with an onset in the postpartum period. The goal of this research was to identify indicators for postpartum depression, that are present during pregnancy, during the delivery and in the postpartum period, in order to identify and treat a high risk client for postpartum depression in time. In this way mental health will be promoted. In the first part of the research, an exploratory, descriptive design was used within the context of a private and provincial baby clinic on the Westrand. The research firstly consisted of a literature study about the indicators for postpartum depression. A questionnaire was compiled from this literature study and it was used to collect data in a private and provincial clinic. A descriptive and explanatory design was used in the second part of the research study, to determine a connection between the indicators of postpartum depression and a diagnosis of postpartum depression. The test sample comprised of all the women who visited a postpartum baby clinic (private as well as provincial) in the postpartum period, who's baby was six months or younger. The questionnaire was completed with their visit to the baby clinic and then returned to the respective fieldworkers.