Thesis (M.Ost.)--Unitec New Zealand, 2009. / Includes bibliographical references (leaves 59-62).

Meta-analysis is an important statistical tool for systematic reviews and evidence-based medicine. Extracting the observed effect sizes, assessing the magnitude of heterogeneity, choosing the suitable statistical model, and interpreting the summary effect size are four key steps in meta-analysis. It is known that each of the above steps has its own unique characteristics and may require some specific attention. As an example, the observed effect sizes from individual studies may not be reported in the same scale and hence cannot be combined directly. Another example is on selecting a model for meta-analysis from the common-effect model and the random-effects model. When a meta-analysis contains only few studies, the common-effect model and the random-effects model will often lead to misleading or unreliable results. In the first part of the thesis, we give a brief introduction on evidence-based medicine, systematic reviews and meta-analysis. We will also show their practical importance, display their relationships, and present a motivating example for conducting a meta-analysis. In Chapter 2, we first review the common effect sizes in meta-analysis for both continuous data and binary data. How to combine different categories of effect sizes is a critical issue after extracting the observed effect sizes from the clinical studies in the literature. For continuous data, researchers have recently proposed methods that transform the five number summary to the sample mean and standard deviation (Hozo et al., 2005; Wan et al., 2014; Luo et al., 2018). For binary data, the transformation from the odds ratio (OR) to the relative risk (RR) in the cohort study was proposed by Zhang and Yu (1998). To the best of our knowledge, however, there is little work in the literature that converts OR to RR in the case-control study. In view of this, we establish a new formula for this transformation to fulfill the gap. The performance of the new method will be examined through simulations and real data analysis. Our method and formulas can not only handle meta-analyses with different effect sizes, but also offer some insights for medical researchers to further understand the meaning of OR and RR in both cohort and case-control studies. In Chapter 3, we first give a brief introduction on the three available models in meta-analysis: the common-effect model, the random-effects model, and the fixed-effects model. When a meta-analysis contains only few studies, the common-effect model and the random-effects model will often lead to misleading or unreliable results. In contrast, the fixed-effects model is capable to provide a good compromise between the existing two models. In this chapter, we propose to further improve the estimation accuracy of the average effect in the fixed-effects model by assigning different weight for each study as well as fully utilizing the information in the within-study variances. Through theory and simulation, we demonstrate that the fixed-effects model can serve as the most convincing model for meta-analysis with few studies. And most importantly, with a total of three models, we expect that meta-analysis can be conducted more flexibly, more meaningfully, and more accurately. In Chapter 4, we first give a brief introduction on the heterogeneity in meta-analysis. We then review the methods for quantifying heterogeneity in three directions as follows: the tests for heterogeneity, the estimates of the between-study variance, and the measures of the impact of heterogeneity. Note that most existing methods were derived under the assumption of known within-study variances. In practice, however, a direct use of the reported within-study variance estimates may largely reduce the power of the tests and also lower the accuracy of the estimates, especially when the sample sizes in some studies are not sufficiently large. To overcome this problem, we propose a family of shrinkage estimators for the within-study variances that are able to borrow information across the studies, and derive the optimal shrinkage parameters under the Stein loss function. We then apply the new estimates of the within-study variances to some well-known methods for measuring heterogeneity. Simulation studies and real data examples show that our shrinkage estimators can dramatically reduce the estimation bias and hence improve the exiting literature. Keywords: Common-effect model, Effect size, Fixed-effects model, Heterogeneity, Meta-analysis, Odds ratio, Random-effects model, Relative risk, Risk ratio

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There has recently been an increased pressure in all-healthcare disciplines to provide interventions that are scientific, safe, efficient and cost-effective. Evidence-based practice is said to be the current best approach to address these attributes. All healthcare professionals including physiotherapists need to adopt it. Numerous physiotherapy studies have been carried out to ascertain the attitudes towards, knowledge of, engagement in as well as the barriers of evidence-based practice. These studies were mostly carried out in the developed countries and almost none in the devloping African countries. By means of an exploratory cross-sectional study, deploying both quantitative and qualitative methods, this study investigated the Tanzanian physiotherapists attitudes towards the concept of evidence-absed practice. The study also examined the knowledge that they possess, that could enable them engage in evidence-based related activities. In addition, this study explored the barriers they experience while practicing evidence-based practice.

Title: Analysis of Pharmacotherapy by patients with diagnosis of arterial hypertension Student: Vasiliki Kontou Tutor: Prof. RNDr. Jiri Vlcek, CSs Department of Social and Clinical Pharmacy, Charles University of Prague, Faculty of Pharmacy in Hradec Kralove Introduction: Arterial Hypertension (AH) is characterized by elevated blood pressure, which often leads to increased morbidity and mortality. AH divided into primary and secondary. Aim: In the theoretical part the aim is to analyse the etiopathogenesis, methods of diagnosis and the treatment strategies of arterial hypertension in the recent literature. In the experimental part the aim is to analyse the provisions of the above diagnosis of arterial hypertension. Method: During a six month period were collected 58 prescriptions with the diagnosis of arterial hypertension from a pharmacy that provided pharmaceutical care in the Greek village, Mytikas. Only one prescription for one patient was analysed. In the prescriptions were collected data on drugs, patients and physicians. Results: The pilot study included 58 prescriptions. Most patients were elderly, over 65 years old and 30% were in age 71 - 80 years. General practitioners prescribed 65% of the medical prescriptions. Most frequently prescribed ARBs with hydrochlorothiazide drugs (27%) and...

Information literacy (IL) is recognized as the overall critical literacy for the 21st Century. Although large amounts of digital information are available, there is concern within higher education that students lack the competencies to assess and analyse sources in terms of relevance to their courses. Information literacy skills are of critical importance in teaching medical students to engage with evidence-based medicine (EBM), often within a problem-based learning (PBL) curriculum. Information practices that underpin academic and professional life should be embedded into the learning experience of the subject, and not taught extraneously in isolated silos. Attitudes of teaching staff at the Faculty of Health Sciences, University of the Witwatersrand towards embedding evidence-based information literacy skills into the Graduate Entry Medical Programme 1 and 2 curriculum were examined. Existing integration of IL skills into the curriculum was shown to be limited, and not as high as perceived by educators. Five barriers against the integration of IL skills, and six opportunities for embedding information literacy, were identified in the curriculum. Awareness of evidence-based practice was found to be high, and collaborative teaching of IL skills with librarians was accepted by a large majority of educators. Dynamic Purposeful Learning (DPL) was proposed as a constructivist framework into which collaborative teaching of IL skills could be placed. DPL draws on active and collaborative learning, as well as cognitive scaffolding and apprenticeship, and is suited to PBL in the context of medical education.

Doctor of Philosophy (PhD) / Introduction The aim of this study was to examine how the term “evidence” was conceived and used among academics and practitioners who teach medicine and public health. The rationale for the study was the widespread debate in the 1990s about evidence in health care. Methods Qualitative data were collected between 1996 to 1999. The core data came from unstructured interviews with researchers and practitioners linked to the Faculty of Medicine, University of Sydney. Other sources of data were: participant observation of group interactions in the Faculty of Medicine and at national and international conferences about evidence in health care; discourse in health care literature; and Internet posting to an international “evidence-based health” Email discussion list. The Grounded Theory method was adopted to analyse and interpret these data. The process involved systematic coding of the data to develop conceptual categories. These categories were employed to formulate propositions about the topic of evidence and how it was conceived and used by the study participants. Results Researchers and practitioners often discussed evidence from a “realist” view: that is they valued scientifically derived and rigorously substantiated knowledge about the natural world. Yet despite their widely shared epistemological perspectives, study participants presented several diverse concepts of evidence. Their ideas were also dynamic and evolving, and often influenced by the developing (local and international) debates and controversies about evidence-based medicine (EBM). Grounded Theory analysis leads to the selection of a core “social process”. This is a core conceptual category that draws together the ideas observed in the data, and that is adopted to present the study findings. In this study, “judgement” was identified as the core social process to underpin all examined reflections and discussions about evidence. Study participants defined the concept of evidence through a combination of description and appraisal. Evidence was described in three ways, i.e.: as a “measure of reality”, by its “functional role”, or as a “constructed product”. Evidence was also appraised on three “dimensions”, i.e.: “benchmarked”, “applied” and “social” dimensions of evidence. Participants invoked these concepts of evidence differently when forming their own judgements about medical or public health knowledge; when making decisions about clinical practice; and when using argument and persuasion to influence the judgements of others. Many researchers and practitioners also modified their judgements on evidence in the light of EBM. This was based on perceptions that EBM had become a dominant rhetoric within health care, which had the potential to channel the flow of resources. This led to an increasing consideration of the “social dimension” of evidence, and of the social construction and possible “misuse” of the term evidence. Conclusions The concept of evidence is presented in this study as a multi-dimensional construct. I have proposed that the three descriptions and three dimensions of evidence presented in this study, and recognition of the way these may be invoked when forming and influencing judgments, can be used as a basis for communicating about evidence in medicine and public health among colleagues and with students. There are significant gaps in knowledge (based on empirical research) about the social dimension of evidence. Particularly, in situations where researchers and practitioners wish to employ the concept of evidence to influence others’ medical and public health practice and wider social policy.

Thesis (M. Med. Sc.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 47-55).

Thesis (Ph. D.)--Open University. BLDSC no. DX242927.

published_or_final_version / Medical Sciences / Master / Master of Medical Sciences