Epidemiology and Biostatistics

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    Does a history of sexual and physical childhood abuse contribute to HIV infection risk in adulthood A study among postnatal women in Harare Zimbabwe
    Simukai Shamu; Patience Shamu; Christina Zarowsky; Marleen Temmerman; Tamara Shefer; Naeemah Abrahams
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    Health Care Providers Challenges to HighQuality HIV Care and Antiretroviral Treatment Retention in Rural South Africa
    A Julien; S Anthierens; A van Rie; R West; Meriam Maritze; Rhian Twine; Kathleen Kahn; Sheri Lippman; Audrey Pettifor; H Leslie
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    All nonadherence is equal but is some more equal than others Tuberculosis in the digital era
    HR Stagg; M Flook; A Martinecz; K Kielmann; E et al; Katherine Fielding
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    The association between HIV infection and pulmonary function in a rural African population
    M Varkila; Alinda Vos; R Barth; H Tempelman; W Deville; E et al; Kerstin Klipstein-Grobusch
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    Exploring the perception of and attitude towards preconception care service provision and utilisation in a South Western Nigerian community – a qualitative study
    (School of Public Health, University of the Witwatersrand, Johannesburg, South Africa, 2021-02) Ojifinni, Oludoyinmola O.; Munyewende, Pascalia O.; Ibisomi, Latifat
    Background: Hospital-based, quantitative studies in Nigeria show low levels of knowledge and use of preconception care (PCC) services. This study explored the perception of and attitude towards PCC in a southwestern Nigerian community qualitatively. Data Source and Methods: Focus group discussions (FGDs) were held with 57 purposively selected adult women and men and key informant interviews (KIIs) with one female and one male community leader in Ibadan North Local Government Area, Oyo State, Nigeria in 2018. The FGDs and KIIs held within the community were digitally recorded, transcribed verbatim and analysed thematically. Results: Participants placed PCC in the context of marriage, describing its importance for addressing effects of adverse exposures on pregnancy and ensuring positive pregnancy outcomes. Conclusion: Barriers to PCC uptake mentioned included lack of awareness and prohibitive service costs. Expressing their willingness to use and promote PCC use, they stated the need to ensure PCC uptake through improved awareness at the community level.
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    Classical Cardiovascular Risk Factors and HIV are Associated With Carotid IntimaMedia Thickness in Adults From SubSaharan Africa Findings From H3Africa AWIGen Study
    (2019-06-07) Boua P; Ali S; Soo C
    Background-—Studies on the determinants of carotid intima-media thickness (CIMT), a marker of sub-clinical atherosclerosis, mostly come from white, Asian, and diasporan black populations. We present CIMT data from sub-Saharan Africa, which is experiencing a rising burden of cardiovascular diseases and infectious diseases. Methods and Results-—The H3 (Human Hereditary and Health) in Africa’s AWI-Gen (African-Wits-INDEPTH partnership for Genomic) study is a cross-sectional study conducted in adults aged 40 to 60 years from Burkina Faso, Kenya, Ghana, and South Africa. Cardiovascular disease risk and ultrasonography of the CIMT of right and left common carotids were measured. Multivariable linear and mixed-effect multilevel regression modeling was applied to determine factors related to CIMT. Data included 8872 adults (50.8% men), mean age of 50 6 years with age- and sex-adjusted mean ( SE) CIMT of 640 123lm. Participants from Ghana and Burkina Faso had higher CIMT compared with other sites. Age (b = 6.77, 95%CI [6.34–7.19]), body mass index (17.6[12.5–22.8]), systolic blood pressure (7.52[6.21–8.83]), low-density lipoprotein cholesterol (5.08[2.10–8.06]) and men (10.3[4.75– 15.9]) were associated with higher CIMT. Smoking was associated with higher CIMT in men. High-density lipoprotein cholesterol (12.2 [17.9– 6.41]), alcohol consumption (–13.5 [19.1–7.91]) and HIV (8.86 [15.7–2.03]) were inversely associated with CIMT. Conclusions-—Given the rising prevalence of cardiovascular diseases risk factors in sub-Saharan Africa, atherosclerotic diseases may become a major pan-African epidemic unless preventive measures are taken particularly for prevention of hypertension, obesity, and smoking. HIV-specific studies are needed to fully understand the association between HIV and CIMT in sub-Saharan Africa
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    Variation by Geographic Scale in the Migration-Environment Association: Evidence from Rural South Africa
    (Federal Institute for Population Research, 2017) Hunter, L.M.; Leyk, S.; Maclaurin, G.J.; Nawrotzki, R.; Twine, W.; Erasmus, B.F.N.; Collinson, M.
    Scholarly understanding of human migration’s environmental dimensions has greatly advanced in the past several years, motivated in large part by public and policy dialogue around “climate migrants”. The research presented here advances current demographic scholarship both through its substantive interpretations and conclusions, as well as its methodological approach. We examine temporary rural South African outmigration as related to household-level availability of proximate natural resources. Such “natural capital” is central to livelihoods in the region, both for sustenance and as materials for market-bound products. The results demonstrate that the association between local environmental resource availability and outmigration is, in general, positive: households with higher levels of proximate natural capital are more likely to engage in temporary migration. In this way, the general findings support the “environmental surplus” hypothesis that resource security provides a foundation from which households can invest in migration as a livelihood strategy. Such insight stands in contrast to popular dialogue, which tends to view migration as a last resort undertaken only by the most vulnerable households. As another important insight, our findings demonstrate important spatial variation, complicating attempts to generalize migration-environment findings across spatial scales. In our rural South African study site, the positive association between migration and proximate resources is actually highly localized, varying from strongly positive in some villages to strongly negative in others. We explore the socio-demographic factors underlying this “operational scale sensitivity”. The cross-scale methodologies applied here offer nuance unavailable within more commonly used global regression models, although also introducing complexity that complicates story-telling and inhibits generalizability.
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    Social accountability and nursing education in South Africa
    (2015) Armstrong, S.J; Rispel, L.C
    BACKGROUND: There is global emphasis on transforming health workforce education in support of universal health coverage. OBJECTIVE: This paper uses a social accountability framework, specifically the World Health Organization's six building blocks for transformative education, to explore key informants' perspectives on nursing education in South Africa. METHODS: Using a snowballing sampling technique, 44 key informants were selected purposively on the basis of their expertise or knowledge of the research area. Semi-structured interviews were conducted with the key informants after informed consent had been obtained. The interviews were analysed using template analysis. RESULTS: South Africa has strategic plans on human resources for health and nursing education, training, and practice and has a well-established system of regulation and accreditation of nursing education through the South African Nursing Council (SANC). Key informants criticised the following: the lack of national staffing norms; sub-optimal governance by both the SANC and the Department of Health; outdated curricula that are unresponsive to population and health system needs; lack of preparedness of nurse educators; and the unsuitability of the majority of nursing students. These problems are exacerbated by a perceived lack of prioritisation of nursing, resource constraints in both the nursing education institutions and the health training facilities, and general implementation inertia. CONCLUSION: Social accountability, which is an essential component of transformative education, necessitates that attention be paid to the issues of governance, responsive curricula, educator preparedness, and appropriate student recruitment and selection.
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    Predictors of health care use by adults 50 years and over in a rural South African setting
    (2014) Ameh, S; Kahn, K; Tollman, S.M; et al
    BACKGROUND: South Africa's epidemiological transition is characterised by an increasing burden of chronic communicable and non-communicable diseases. However, little is known about predictors of health care use (HCU) for the prevention and control of chronic diseases among older adults. OBJECTIVE: To describe reported health problems and determine predictors of HCU by adults aged 50+ living in a rural sub-district of South Africa. DESIGN: A cross-sectional study to measure HCU was conducted in 2010 in the Agincourt sub-district of Mpumalanga Province, an area underpinned by a robust health and demographic surveillance system. HCU, socio-demographic variables, reception of social grants, and type of medical aid were measured, and compared between responders who used health care services with those who did not. Predictors of HCU were determined by binary logistic regression adjusted for socio-demographic variables. RESULTS: Seventy-five percent of the eligible adults aged 50+ responded to the survey. Average age of the targeted 7,870 older adults was 66 years (95% CI: 65.3, 65.8), and there were more women than men (70% vs. 30%, p<0.001). All 5,795 responders reported health problems, of which 96% used health care, predominantly at public health facilities (82%). Reported health problems were: chronic non-communicable diseases (41% - e.g. hypertension), acute conditions (27% - e.g. flu and fever), other conditions (26% - e.g. musculoskeletal pain), chronic communicable diseases (3% - e.g. HIV and TB), and injuries (3%). In multivariate logistic regression, responders with chronic communicable disease (OR=5.91, 95% CI: 1.44, 24.32) and non-communicable disease (OR=2.85, 95% CI: 1.96, 4.14) had significantly higher odds of using health care compared with those with acute conditions. Responders with six or more years of education had a two-fold increased odds of using health care (OR=2.49, 95% CI: 1.27, 4.86) compared with those with no formal education. CONCLUSION: Chronic communicable and non-communicable diseases were the most prevalent and main predictors of HCU in this population, suggesting prioritisation of public health care services for chronic diseases among older people in this rural setting.
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    Barriers to accessing health care in Nigeria: implications for child survival
    (2014) Adedini, S A; Odimegwu, C; Bamiwuye, S A; et al
    Background: Existing studies indicate that about one in every six children dies before age five in Nigeria. While evidence suggests that improved access to adequate health care holds great potential for improved child survival, previous studies indicate that there are substantial barriers to accessing health care in Nigeria. There has not been a systematic attempt to examine the effects of barriers to health care on under-five mortality in Nigeria. This study is designed to address this knowledge gap. Data and method: Data came from a nationally representative sample of 18,028 women (aged 15 49) who had a total of 28,647 live births within the 5 years preceding the 2008 Nigeria Demographic and Health Survey. The risk of death in children below age five was estimated using Cox proportional hazard models and results are presented as hazards ratios (HR) with 95% confidence intervals (CI). Results: Results indicate higher under-five mortality risks for children whose mothers had cultural barriers and children whose mothers had resource-related barriers to health care (HR: 1.44, CI: 1.32 1.57, pB0.001), and those whose mothers had physical barriers (HR: 1.13, CI: 1.04 1.24, pB0.001), relative to children whose mothers reported no barriers. Barriers to health care remained an important predictor of child survival even after adjusting for the effects of possible confounders. Conclusion: Findings of this study stressed the need for improved access to adequate health care in Nigeria through the elimination of barriers to access. This would enable the country to achieve a significant reduction in childhood mortality.