Aims: The aims of this thesis were to investigate the risk of severe maternal morbidity amongst women from different socioeconomic groups in the UK, explore why these differences exist and compare these findings to the setting in Australia. Methods: Three separate analyses were conducted. The first used UK Obstetric Surveillance System (UKOSS) data to assess the incidence and independent odds of severe maternal morbidity by socioeconomic group in the UK. The second analysis used quantitative and qualitative data from the 2010 UK National Maternity Survey (NMS) to explore the possible reasons for the difference in odds of morbidity between socioeconomic groups in the UK. The third analysis used data from the Victorian Perinatal Data Collection (VPDC) unit in Austra lia to assess the incidence and odds of severe maternal morbidity by socioeconomic group in Victoria. Results: The UKOSS analysis showed that compared with women from the highest socioeconomic group, women in the lowest 'unemployed' group had 1.22 (95%CI: 0.92 - 1.61) times greater odds associated with severe maternal morbidity. The NMS analysis demonstrated that independent of ethnicity, age and parity, women from the lowest socioeconomic quintiJe were 60% less likely to have had any antenatal care (aOR 0.40; 95%CI 0.18 - 0.87), 40% less likely to have been seen by a health professional prior to 12 weeks gestation (aOR 0.62; 95%CI 0.45 - 0.85) and 45% less likely to have had a postnatal check with their doctor (aOR 0.55; 95%CI 0.42 - 0.70) compared to women from the highest quintile. The Victorian analysis showed that women from the lowest socioeconomic group were 21% (aOR 1.21 ; 95% CI 1.00 - 1.47) more likely and that Aboriginal and Torres Strait Islander women were twice (aOR 2.02; 95%CI 1.32 - 3.09) as likely to experience severe morbidity. Discussion: The resu lts suggest that women from the lowest socioeconomic group in the UK and in Victoria have increased odds of severe maternal morbidity. Further research is needed into why these differences exist and efforts must be made to ensure that these women are appropriately prioritised in the future planning of maternity services provisio n in the UK and Australia.

This thesis presents an empirical investigation into substance use, situational characteristics and sexual outcomes in men who have sex with men (MSM) motivated by the high rates of substance use in MSM; the association between substance use and sexual risk behaviours in MSM; the lack of specific theory addressing relationships between substance use, sexual interactions and social interactions between MSM; and the need for clearer understandings of encounter-level associations with sexual risk. Qualitative metasynthesis. This thesis begins with laying the methodological groundwork for a qualitative metasynthesis that theorises the relationship between substance use and social spaces in MSM, with a particular focus on sexual outcomes. The qualitative metasynthesis derives the key organising perspective of ‘littoral spaces’ in which substance use is associated with a pre-planned, though temporary, escape from the boundaries of everyday life to engage in maximal sensory exploration, including through sexual contact. <b>Systematic review of multiple-event analyses. The thesis then turns to a systematic review of previous quantitative multiple-event analyses examining associations between situational characteristics and sexual outcomes, which establishes the need for additional multiple-event analyses addressing specific substance use, location of sex, partner serodiscordance and partner type. Multiple-event analyses. Finally, informed by the qualitative metasynthesis and the systematic review of event-level analyses, this thesis presents multiple-event analyses addressing unprotected anal intercourse (UAI), pleasure and control as sexual outcomes in MSM in England. These analyses found that substance use was associated with greater odds of UAI and pleasure, but not with control, and that non-private locations of sex were associated with decreased odds of UAI and pleasure, but not control. Furthermore, there was sparse evidence of interactions between respondent and partner substance use and between respondent substance use and location of sex in associations with sexual outcomes. These analyses contribute to understandings of associations between substance use, situational characteristics and sexual risk behaviour by presenting the first known analyses on MSM in England and by examining sexual outcomes besides UAI.

A automedicação retrata o princípio do próprio indivíduo buscar espontaneamente por algum medicamento, que considere adequado para resolver um problema de saúde. Esta prática, ainda, é pouco explorada em idosos, principalmente a partir de dados populacionais. Desse modo, o objetivo do presente estudo foi analisar a pratica de automedicação em idosos no Município de São Paulo. Trata-se de um estudo transversal, de base populacional, cujos dados foram obtidos do Estudo SABE - Saúde, Bem-estar e Envelhecimento. A amostra foi constituída de 1.257 idosos que utilizaram medicamentos com idade de 60 anos e mais. Para coleta de informações utilizaram-se as seções do questionário sobre Informações pessoais (A), Estado de saúde (C), Medicamento (E), Uso e Acesso a serviços (F) e Historia de trabalho e fontes de renda (H). Os medicamentos consumidos na automedicação foram classificados de acordo com a Anatomical Therapeutical Chemical Classification System (ATC). Na análise dos dados utilizou-se o pacote estatístico STATA com realização de regressão logística. Considerou-se nível de significância de p<0,05. A prevalência de automedicação foi de 42,3%. Entre os medicamentos mais usados estão os analgésicos/antiinflamatórios (40,0%) e vitaminas (8,7%). No grupo de idosos que usou automedicação 45,0% pertenciam ao sexo feminino, 44,4% apresentaram 60 a 74 anos, 46,2% utilizaram o serviço público de saúde, 50,8% não consultaram o médico nos últimos 12 meses, 48,4% consumiram cinco ou mais medicamentos e 50,7% relataram não possuir doenças cronicas. O idoso foi o principal responsável pela indicação da automedicação (65%). Na análise múltipla, observou-se que empregar cinco ou mais medicamentos (OR=1,75) e possuir baixa escolaridade aumentou a chance dos idosos usarem a automedicação e possuir plano de saúde privado (OR=0,72), ter uma e mais doenças (OR=0,57) e idade igual ou superior a 75 anos (OR=0,69) diminuiu a chance de usar a automedicação. As intervenções educativas com o objetivo de reduzir a automedicação na população geriátrica devem contemplar, especialmente os usuários de polifarmácia, aqueles com baixa escolaridade e indivíduos na faixa etária dos 60 74 anos, tendo em vista que o próprio idoso é o principal responsável pela decisão de praticar a automedicação. / Self-medication depicts the principle of the individual seeking spontaneously by some drug, which it deems appropriate to resolve a health problem. This practice, though, is little explored in the elderly, primarily using population data. Thus, the objective of this study was to analyze self-medication in the elderly in São Paulo. It is a cross-sectional, population-based, whose data were obtained from the SABE Study - Health, Welfare and Ageing. The sample consisted of 1,257 seniors who used drugs at the age of 60 years and more. To collect the information we used sections of the questionnaire on personal information (A) Health status (C), drug (E), Use and Access to services (F) and work history and income sources (H). The drugs used in self-medication were classified according to the Anatomical Therapeutic Chemical Classification System (ATC). In the data analysis used the STATA statistical package with performance of logistic regression. It was considered a significance level of p <0.05. The prevalence of self-medication was 42,3%. Among the most commonly used drugs are analgesics, anti-inflammatory drugs (40.0%) and vitamins (8.7%). In the elderly group that used self-medication 45.5% were female, 44.4% had 60 to 74 years, 50.8% did not consult the doctor in the last twelve months, 46.2% used public insurance, 48,4% used five or more drugs and 50.7% reported not having chronic diseases. The senior was the main responsible for the appointment of self-medication (65%). In the multivariate analysis, we observed that employ five or more medications (OR = 1.75) and have low education increased the likelihood of using self-medication and the elderly have private health insurance (OR = 0.72), and have a more diseases (OR = 0.57) and age less than 75 years (OR = 0.69) decreased the chance of using self-medication. Educational interventions aimed at reducing self-medication should include in the geriatric population, especially those using polypharmacy, those with low education and individuals aged 60 to 74 years, given that the elderly person is mainly responsible for the decision to practice self-medication.

A automedicação retrata o princípio do próprio indivíduo buscar espontaneamente por algum medicamento, que considere adequado para resolver um problema de saúde. Esta prática, ainda, é pouco explorada em idosos, principalmente a partir de dados populacionais. Desse modo, o objetivo do presente estudo foi analisar a pratica de automedicação em idosos no Município de São Paulo. Trata-se de um estudo transversal, de base populacional, cujos dados foram obtidos do Estudo SABE - Saúde, Bem-estar e Envelhecimento. A amostra foi constituída de 1.257 idosos que utilizaram medicamentos com idade de 60 anos e mais. Para coleta de informações utilizaram-se as seções do questionário sobre Informações pessoais (A), Estado de saúde (C), Medicamento (E), Uso e Acesso a serviços (F) e Historia de trabalho e fontes de renda (H). Os medicamentos consumidos na automedicação foram classificados de acordo com a Anatomical Therapeutical Chemical Classification System (ATC). Na análise dos dados utilizou-se o pacote estatístico STATA com realização de regressão logística. Considerou-se nível de significância de p<0,05. A prevalência de automedicação foi de 42,3%. Entre os medicamentos mais usados estão os analgésicos/antiinflamatórios (40,0%) e vitaminas (8,7%). No grupo de idosos que usou automedicação 45,0% pertenciam ao sexo feminino, 44,4% apresentaram 60 a 74 anos, 46,2% utilizaram o serviço público de saúde, 50,8% não consultaram o médico nos últimos 12 meses, 48,4% consumiram cinco ou mais medicamentos e 50,7% relataram não possuir doenças cronicas. O idoso foi o principal responsável pela indicação da automedicação (65%). Na análise múltipla, observou-se que empregar cinco ou mais medicamentos (OR=1,75) e possuir baixa escolaridade aumentou a chance dos idosos usarem a automedicação e possuir plano de saúde privado (OR=0,72), ter uma e mais doenças (OR=0,57) e idade igual ou superior a 75 anos (OR=0,69) diminuiu a chance de usar a automedicação. As intervenções educativas com o objetivo de reduzir a automedicação na população geriátrica devem contemplar, especialmente os usuários de polifarmácia, aqueles com baixa escolaridade e indivíduos na faixa etária dos 60 74 anos, tendo em vista que o próprio idoso é o principal responsável pela decisão de praticar a automedicação. / Self-medication depicts the principle of the individual seeking spontaneously by some drug, which it deems appropriate to resolve a health problem. This practice, though, is little explored in the elderly, primarily using population data. Thus, the objective of this study was to analyze self-medication in the elderly in São Paulo. It is a cross-sectional, population-based, whose data were obtained from the SABE Study - Health, Welfare and Ageing. The sample consisted of 1,257 seniors who used drugs at the age of 60 years and more. To collect the information we used sections of the questionnaire on personal information (A) Health status (C), drug (E), Use and Access to services (F) and work history and income sources (H). The drugs used in self-medication were classified according to the Anatomical Therapeutic Chemical Classification System (ATC). In the data analysis used the STATA statistical package with performance of logistic regression. It was considered a significance level of p <0.05. The prevalence of self-medication was 42,3%. Among the most commonly used drugs are analgesics, anti-inflammatory drugs (40.0%) and vitamins (8.7%). In the elderly group that used self-medication 45.5% were female, 44.4% had 60 to 74 years, 50.8% did not consult the doctor in the last twelve months, 46.2% used public insurance, 48,4% used five or more drugs and 50.7% reported not having chronic diseases. The senior was the main responsible for the appointment of self-medication (65%). In the multivariate analysis, we observed that employ five or more medications (OR = 1.75) and have low education increased the likelihood of using self-medication and the elderly have private health insurance (OR = 0.72), and have a more diseases (OR = 0.57) and age less than 75 years (OR = 0.69) decreased the chance of using self-medication. Educational interventions aimed at reducing self-medication should include in the geriatric population, especially those using polypharmacy, those with low education and individuals aged 60 to 74 years, given that the elderly person is mainly responsible for the decision to practice self-medication.

Noventa e três professores de educação física (PrEF) de 5a a 8a séries da rede pública (44) e da rede particular de ensino (49) foram solicitados a responder um questionário de 54 itens, para estabelecer o nível de conhecimento sobre asma e seu manuseio, exercício e suas atitudes em relação à asma e suas crises. Os questionários foram preenchidos durante o horário escolar sem nenhuma consulta e houve um alto índice de resposta dos professores das escolas públicas (86%) e das escolas particulares (69%). Nossos resultados mostram que os PrEF das escolas públicas e particulares apresentaram conhecimento regular sobre asma (60%) e exercício (66,6%), entretanto o conhecimento sobre os medicamentos para asma foi limitado (44%). Não foi observada diferença no conhecimento sobre asma entre PrEF de escolas públicas e particulares. Embora metade dos professores apresentasse experiência prévia em asma (pessoal, 13,8%; familiar, 39%), o nível de conhecimento foi similar quando comparado com aqueles que não tinham experiência prévia sobre a doença. A maioria dos professores também relatou a necessidade de informações sobre a asma, preferencialmente por meio de aula expositiva com médicos ou treinamento prático. Nossos resultados sugerem que os professores de educação física da rede pública e particular de ensino necessitam de maiores informações sobre asma, independente de apresentarem uma experiência prévia sobre a doença. Além disto, foi observado que o menor conhecimento sobre o assunto foi relativo aos medicamentos utilizados pelos asmáticos / Ninety-three teachers of physical education (TPE) from public (44) and private (49) elementary schools in Sao Paulo were asked to respond a 54-item questionnaire about general asthma knowledge, exercise, medication and teacher\'s attitude toward asthma attack. Questionnaires were answered during school time without any consulting and there was a high response rate from public (86%) and private (69%) school teachers. Our results showed that TPE from public and private schools presented a regular knowledge about asthma (60%) and exercise (66.6%), nevertheless, they showed a low knowledge about asthma medication (44%). We did not observe any difference on asthma knowledge between TPE from public and private schools. Although half of the teachers presented previous asthma experience (personal, 13.8%; family, 39%), they had similar knowledge compared to teachers without previous asthma experience. Most teachers also related necessity of information on asthma through expositive classes with physicians or practical training. Our results showed that teachers of physical education from public and private schools in Brazil require information on asthma independent on previous experience on asthma. Besides, these teachers presented lower knowledge on asthma medication

Stroke and myocardial infarction (MI) are serious conditions whose burdens vary by socio-demographic and geographic factors. Although several studies have investigated and identified disparities in burdens of these conditions at the county and state levels, little is known regarding their geographic epidemiology at the neighborhood level. Both conditions require emergency treatments and therefore timely geographic accessibility to appropriate care is critical. Investigation of disparities in geographic accessibility to stroke and MI care and the role of Emergency Medical Services (EMS) in reducing treatment delays are vital in improving health outcomes. Therefore, the objectives of this work were to: (i) classify neighborhoods based on socio-demographic and geographic characteristics; (ii) investigate spatial patterns of neighborhood level mortality; (iii) identify disparities in geographic accessibility to stroke and MI care; and (iv) identify disparities in EMS transport times for stroke and MI patients in East Tennessee. Fuzzy cluster analysis was used to classify neighborhoods into peer neighborhoods (PNs) based on their socio-demographic and geographic factors. Neighborhood level spatial patterns of stroke and MI mortality risks were investigated using Spatial Empirical Bayesian smoothing techniques and neighborhoods with high mortality risks identified using spatial scan statistics. Travel times to stroke and cardiac care facilities were computed using network analysis to investigate geographic accessibility. Records of over 3,900 suspected stroke and MI patients, from two EMS providers, were used to investigate disparities in EMS transport delays. Four distinct PNs were identified. The highest stroke/MI mortality risks were observed in less affluent, urban PNs, and lowest risks in more affluent, suburban PNs. Several significant (p<0.0001) stroke and MI high mortality risk spatial clusters were identified. Approximately 8% and 15% of the population did not have timely accessibility to appropriate stroke and MI care, respectively. The disparity was greatest for populations in rural areas. Important disparities in EMS transport delays were identified, with the travel time to a hospital contributing the longest delay. The identified disparities in neighborhood characteristics, mortality risks, geographic accessibility, and EMS transport delays are invaluable in guiding resource allocation, service provision, and policy decisions to support evidence-based population health planning and policy.

Noventa e três professores de educação física (PrEF) de 5a a 8a séries da rede pública (44) e da rede particular de ensino (49) foram solicitados a responder um questionário de 54 itens, para estabelecer o nível de conhecimento sobre asma e seu manuseio, exercício e suas atitudes em relação à asma e suas crises. Os questionários foram preenchidos durante o horário escolar sem nenhuma consulta e houve um alto índice de resposta dos professores das escolas públicas (86%) e das escolas particulares (69%). Nossos resultados mostram que os PrEF das escolas públicas e particulares apresentaram conhecimento regular sobre asma (60%) e exercício (66,6%), entretanto o conhecimento sobre os medicamentos para asma foi limitado (44%). Não foi observada diferença no conhecimento sobre asma entre PrEF de escolas públicas e particulares. Embora metade dos professores apresentasse experiência prévia em asma (pessoal, 13,8%; familiar, 39%), o nível de conhecimento foi similar quando comparado com aqueles que não tinham experiência prévia sobre a doença. A maioria dos professores também relatou a necessidade de informações sobre a asma, preferencialmente por meio de aula expositiva com médicos ou treinamento prático. Nossos resultados sugerem que os professores de educação física da rede pública e particular de ensino necessitam de maiores informações sobre asma, independente de apresentarem uma experiência prévia sobre a doença. Além disto, foi observado que o menor conhecimento sobre o assunto foi relativo aos medicamentos utilizados pelos asmáticos / Ninety-three teachers of physical education (TPE) from public (44) and private (49) elementary schools in Sao Paulo were asked to respond a 54-item questionnaire about general asthma knowledge, exercise, medication and teacher\'s attitude toward asthma attack. Questionnaires were answered during school time without any consulting and there was a high response rate from public (86%) and private (69%) school teachers. Our results showed that TPE from public and private schools presented a regular knowledge about asthma (60%) and exercise (66.6%), nevertheless, they showed a low knowledge about asthma medication (44%). We did not observe any difference on asthma knowledge between TPE from public and private schools. Although half of the teachers presented previous asthma experience (personal, 13.8%; family, 39%), they had similar knowledge compared to teachers without previous asthma experience. Most teachers also related necessity of information on asthma through expositive classes with physicians or practical training. Our results showed that teachers of physical education from public and private schools in Brazil require information on asthma independent on previous experience on asthma. Besides, these teachers presented lower knowledge on asthma medication

Dengue fever affects over 390 million people annually worldwide and is of particu- lar concern in Southeast Asia where it is one of the leading causes of hospitalization. Modeling trends in dengue occurrence can provide valuable information to Public Health officials, however many challenges arise depending on the data available. In Thailand, reporting of dengue cases is often delayed by more than 6 weeks, and a small fraction of cases may not be reported until over 11 months after they occurred. This study shows that incorporating data on Google Search trends can improve dis- ease predictions in settings with severely underreported data. We compare penalized regression approaches to seasonal baseline models and illustrate that incorporation of search data can improve prediction error. This builds on previous research show- ing that search data and recent surveillance data together can be used to create accurate forecasts for diseases such as influenza and dengue fever. This work shows that even in settings where timely surveillance data is not available, using search data in real-time can produce more accurate short-term forecasts than a seasonal baseline prediction. However, forecast accuracy degrades the further into the future the forecasts go. The relative accuracy of these forecasts compared to a seasonal average forecast varies depending on location. Overall, these data and models can improve short-term public health situational awareness and should be incorporated into larger real-time forecasting efforts.

The United States continues to be affected by a severe, long-standing nursing shortage that is not projected to resolve within the next 10 or more years. Unsuccessful passage of the National Council Licensure Examination for Registered Nurses (NCLEX-RN) among graduate nurses remains one of several key contributors to the nursing shortage. The goal of this study was to identify if either cumulative fall semester GPA; the overall prenursing science, mathematics, and English GPA; type of high school background; TOEFL score; clinical pass or fail; and on-time program completion best predicted passage of NCLEX-RN. Archived records from the academic years of 2006-2010 of students/graduates of a small, private BSN program were analyzed. A nonconcurrent, prospective design of secondary data was guided by the theoretical implications of the Seidman retention formula that surmises that early identification of academic problems is a necessary precursor to implementations that promote academic success. Significant, positive correlations were found between GPA of prenursing courses and achievement in clinical courses and on-time nursing program completion. Forward and backward, logistic regression procedures revealed that clinical performance was the strongest predictor of NCLEX-RN success but with an inverse relationship. Implications for positive social change include retention of BSN students to improve graduation rates. This ultimately will foster achievement on the NCLEX-RN, resulting in more graduates will be able to competently serve the health care needs of individuals and communities and alleviation of the nursing shortage.

Unexpected findings that contradict well-established relationships between exposures and outcomes are often referred to as “paradoxes” in the epidemiologic literature. For example, the “birth weight paradox” refers to the observed protective association between smoking during pregnancy and infant mortality among low birth weight infants. A recent body of literature suggests that this and several other well-known epidemiologic paradoxes can be attributed to collider bias. Collider bias results from conditioning on a variable that is caused by the exposure or shares common cause with the exposure and is caused by the outcome or shares common causes with the outcome. Several recent epidemiology textbooks and methodological studies further suggest that collider bias is the graphical representation of selection bias, suggesting that these two biases are synonymous. This structural approach to bias is conceptually very useful for defining, describing, and identifying selection bias, but it introduces paradoxes of its own due to contradictory conclusions in the selection and collider bias methodologic literatures about their likely impact on study results in terms of magnitude, direction, and strata affected. Resolving these discrepancies is essential for our theoretical understanding of the relationship between selection and collider bias and has important practical implications for how we teach epidemiology, design studies, and evaluate and quantify the potential effects of bias on our results. For example, while patterns of collider bias coincide qualitatively with the birth weight paradox, the magnitude of collider bias would have to be substantial to reverse the sign of the association, contrary to prevailing beliefs that collider bias only minimally affects our results. To date, the plausibility of collider bias as an explanation for the birth weight paradox has not been empirically evaluated using data in which the paradox is observed.Taken together, these inconsistencies and contradictions suggest that our understanding of selection bias and collider bias remains incomplete. The overarching goal of this dissertation was to advance the theoretical and quantitative understanding of the impact of collider bias on study results to clarify the relationship between selection and collider bias. I began by systematically reviewing the methodologic literature on selection and collider bias. I found that selection bias and collider bias are increasingly treated as synonyms, but that conclusions about the magnitude and direction of selection and collider bias, the stratum affected, and the conditions under which the effects of each type of bias were evaluated are highly inconsistent. This suggested that divergent findings about the impact of selection and collider bias might be resolved by considering the impact of collider bias under a broader set of circumstances. I used microsimulations grounded in the sufficient component cause model to examine collider bias not under the null; interrogate why multiplicative interaction appeared central to the impact of collider bias; and clarify which stratum or strata are affected by collider bias. I identified clear patterns for the magnitude, direction, and strata affected by collider bias and successfully reconciled discrepancies with the selection bias literature. This work also enabled me to interrogate both the causal mechanisms and mathematical principles that underlie collider bias, which revealed how collider bias leads to non-exchangeability and when stratifying on a collider results in bias. Finally, I applied this deeper understanding of the mechanisms underlying collider bias to empirically evaluate the plausibility of collider bias as an explanation for the birth weight paradox. Using microsimulations parameterized with 2015 National Center for Health Statistics Cohort Linked Birth-Infant Mortality, I identified scenarios that successfully reproduced the paradox and all observed relationships between smoking during pregnancy, infant mortality, and low birth weight. These findings strengthen the evidence for the role of collider bias in producing the paradox and shed light on the potential magnitude of unmeasured confounding and direct effects of smoking and low birth weight on infant mortality that may be required for the observed magnitude of the paradox to arise. This work clarifies that almost all selection bias is collider bias; that the effects of collider bias vary in magnitude and direction; that selecting on a collider always leads to bias, but this bias may not occur in the stratum that coincides with our analytical sample; and that collider bias may resolve the birth weight paradox, but is unlikely to explain all epidemiologic paradoxes.