Dissertations / Theses: 'Medical statistics Medical geography'

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Kettermann, Anna. "Estimation of Standardized Mortality Ratio in Geographic Epidemiology." Fogler Library, University of Maine, 2004. http://www.library.umaine.edu/theses/pdf/KettermanA2004.pdf.

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Hernandez, Andres M. "Spatial Modeling of the Social Health Determinants Impact on the Epidemiology of Diseases in Low-, Middle-, and High-income Settings." University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1613686108382205.

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Rytkönen, M. (Mika). "Geographical study on childhood type 1 diabetes mellitus (T1DM) in Finland." Doctoral thesis, University of Oulu, 2004. http://urn.fi/urn:isbn:9514272862.

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Abstract Type 1 diabetes mellitus (T1DM) among children is of a particular importance in Finland, where its incidence is the highest in the world and still increasing. However, the aetiology of T1DM is not fully known. According to current knowledge, both genetic and environmental factors operate together, leading to an attack by the immune system on the insulin-producing beta cells. The purpose of this study was to investigate the geographical variation in the incidence of T1DM among children aged up to 14 years in Finland. Geographical Information Systems (GIS) and Bayesian spatial statistics were applied in a search for unusual spatial patterns and risk factor associations. The incidence of T1DM among children aged up to 14 years showed clear geographical variations in Finland. Living in a rural environment increased the risk for T1DM, and the risk was particularly high among children living in rural heartland areas. There was no association between the variation in T1DM incidence and the zinc and nitrate concentrations of drinking water. A male excess in the incidence of T1DM was seen in the low-incidence areas. The geographical variation in the risk of T1DM was marked only among children aged up to 9 years. Because genetics is a necessary but not a sufficient cause of T1DM, it could be hypothesized that there are some thus far unknown environmental risk factors affecting particularly younger children in Finland. Some of those factors may be related to a rural environment. The geographical variation in the M/F ratio of T1DM was a challenging observation and warrants more analytical study.

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Kim, Hoon. "Bayesian hierarchical spatio-temporal analysis of mortality rates with disease mapping /." free to MU campus, to others for purchase, 1999. http://wwwlib.umi.com/cr/mo/fullcit?p9953872.

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Liu, Lixun. "Exploring ethnic inequalities in cardiovascular disease using Hospital Episode Statistics." Thesis, St Andrews, 2009. http://hdl.handle.net/10023/819.

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Hua, Hairui. "Survival modelling in mathematical and medical statistics." Thesis, University of Birmingham, 2015. http://etheses.bham.ac.uk//id/eprint/5808/.

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An essential aspect of survival analysis is the estimation and prediction of survival probabilities for individuals. For this purpose, mathematical modelling of the hazard rate function is a fundamental issue. This thesis focuses on the novel estimation and application of hazard rate functions in mathematical and medical research. In mathematical research we focus on the development of a semiparametric kernel-based estimate of hazard rate function and a L$_1$ error optimal kernel hazard rate estimate. In medical research we concentrate on the development and validation of survival models using individual participant data from multiple studies. We also consider how to fit survival models that predict individual response to treatment effectiveness, given IPD from multiple trials.

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Coupal, Louis. "The EM algorithm : an overview with applications to medical data." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=56644.

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Owing to their complex design and use of live subjects as experimental units, missing or incomplete data is common place in medical experiments. The great increase in difficulty of maximum likelihood based analysis of incomplete data experiments compared to a similar complete data analysis encourages many medical researchers to ignore cases with missing data in favour of performing a "complete" cases analysis.
The expectation maximization algorithm (EM for short) is often an easily implemented algorithm that provides estimates of parameters in models with missing data. The EM algorithm unifies the theory of maximum likelihood estimation in the context of "missing" data. The general problem of missing data also includes structurally unobservable quantities such as parameters, hyperparameters and latent variables. The nature of its defining steps, the expectation or E-step and the maximization or M-step, gives the user intuitive understanding of the maximization process.
In this Thesis, the EM algorithm is first illustrated through an example borrowed from the field of genetics. The theory of the EM algorithm is formally developed and the special case of exponential families is considered. Issues concerning convergence and inference are discussed. Many examples taken from the medical literature serve to highlight the method's broad spectrum of application in both missing data and unobservable parameter problems.

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Wong, Sik-kwan Francis. "Outcome of a web-based statistic laboratory for teaching and learning of medical statistics." Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B43251687.

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Walker, Stephen Graham. "Bayesian parametric and nonparametric methods with applications in medical statistics." Thesis, Imperial College London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307519.

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Tom, Brian Dermot Ming. "Modelling event-history data in the context of medical statistics." Thesis, University of Cambridge, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624771.

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Paschane, David Michael. "A theoretical framework for the medical geography of health service politics /." Thesis, Connect to this title online; UW restricted, 2003. http://hdl.handle.net/1773/5649.

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Raner, Max. "On logistic regression and a medical application." Thesis, Uppsala universitet, Tillämpad matematik och statistik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-420680.

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Garcia, Lopez Claudia Monica. "From medical geography to germ theory in Colombia, 1860-1900." Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/4303.

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Before the consolidation of the germ theory of human diseases at the end of the nineteenth century, medical explanations about disease causation were dominated by the environmental notions of medical geography. This dissertation explores how nineteenth-century Colombian physicians transformed the medical geographical approach using the early concepts and technologies of the emerging Pasteurian germ theory. I follow this transformation in the cases of periodic fevers (yellow fever and malaria), continuous fevers (typhoid fever and typhus) and leprosy. The analysis reveals that by mid century physicians had incorporated neo-Hippocratic versions of disease causation and French medical geographical ideas in order to make sense of disease of the warm, temperate and cold lands. Their conceptual network revolved around the specific, predisposing and occasional causes in which climate and geography played a determinant role. Evidence indicates that this was the case of periodic fevers of the warm lands (yellow fever and malaria). I argue that the “parasitic” hypothesis of yellow fever was accepted during the controversy around the prophylactic inoculations inspired by Pasteurism that were applied in Colombia in 1887. However, doctors struggled to reconcile the medical geographical and the bacteriological perspective of both yellow fever and malaria. Continuous fevers, on the other hand, were also framed within the medical geography scheme of disease causation. I show how during the debates about typhoid fever and typhus happening in the Colombian highlands during the 70s, 80s and 90s, doctors used medical geographical notions and developed anti-pasteurian arguments, while the international scientific community had identified the specific bacilli for typhoid fever. Finally, I argue that the strong interest of Colombian doctors on leprosy –also understood in neo-Hippocratic terms- that foster the search for local treatments based on Pasteurism (antiseptics in the 1880s and serotherapy in the 1890s) also prompted the extension of the bacteriological model and techniques to other diseases in those decades.

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Joubert, Georgina. "Variable selection in logistic regression, with special application to medical data." Master's thesis, University of Cape Town, 1994. http://hdl.handle.net/11427/17006.

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Bibliography: pages 121-126.
In this thesis, the various methods of variable selection which have been proposed in the statistical, epidemiological and medical literature for prediction and estimation problems in logistic regression will be described. The procedures will be applied to medical data sets. On the basis of the literature review as well as the applications to examples, strengths and weaknesses of the approaches will be identified. The procedures will be compared on the basis of the results obtained, their appropriateness for the specific aim of the analysis, and demands they place on the analyst and researcher, intellectually and computationally. In particular, certain selection procedures using bootstrap samples, which have not been used before, will be investigated, and the partial Gauss discrepancy will be extended to the case of logistic regression. Recommendations will be made as to which approaches are the most suitable or most practical in different situations. Most statistical texts deal with issues regarding prediction, whereas the epidemiological literature focuses on estimation. It is therefore hoped that the thesis will be a useful reference for those, statistically or epidemiologically trained, who have to deal with issues regarding variable selection in logistic regression. When fitting models in general, and logistic regression models in particular, it is standard practice to determine the goodness of fit of models, and to ascertain whether outliers or influential observations are present in a data set. These aspects will not be discussed in this thesis, although they were considered when fitting the models.

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Partlett, Christopher. "Asymmetry and other distributional properties in medical research data." Thesis, University of Birmingham, 2015. http://etheses.bham.ac.uk//id/eprint/6348/.

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The central theme of this thesis is to investigate the use of non-parametric methods for making inferences about a random sample with an unknown distribution function. The overarching aim is the development of new methods to make inferences regarding the nature of the unknown distribution to enhance medical research. Initially,the focus is exclusively on the asymmetry of a random variable. In particular, a recently proposed measure of asymmetry provides the foundation for the proposal and development of a new test for symmetry. The potential applications of the test and measure are applied to a number of medical research settings including randomised trials. Moreover, guidance is provided on its implementation, with particular emphasis on the problem of small sample estimation. This investigation is then generalised to examine asymmetry across multiple studies. In particular, meta-analysis methods are used to synthesise information about the amount of asymmetry in several studies. Further, a detailed simulation study is carried out to investigate the impact of asymmetry on linear models and meta-analyses of randomised trials, in terms of the accuracy of the treatment effect estimate and the coverage of confidence and prediction intervals. Finally, the scope of the investigation is widened to encompass the problem of comparing and synthesising information about the probability density function and cumulative distribution function, based on samples from multiple studies. The meta-analysis of the smooth distribution function estimate is then applied to propose new methods for conducting meta-analyses of diagnostic test accuracy, which have a number of merits compared to the existing methodology.

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Jannetta, Adrian. "Advanced deconvolution techniques and medical radiography." Thesis, Northumbria University, 2005. http://nrl.northumbria.ac.uk/164/.

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Medical radiography is a process by which the internal structures of the human body are imaged using a source of x-rays. The images formed are essentially shadowgrams whose size and intensity is dependent on the geometry of the imaging system and the degree to which the structures attenuate x-ray radiation. The images are blurred because the x-ray source has a finite size, and noisy because the x-ray exposure must be kept as low as possible for the safety of the patient but which also limits the number of photons available for image formation. In such noisy environments traditional methods of Fourier deconvolution have limited appeal. In this research we apply maximum entropy methods (MEM) to some radiological images. We justify the choice of MEM over other deconvolution schemes by processing a selection of artificial images in which the blur and noise mimic the real situation but whose levels are known a priori. A hybrid MEM scheme is developed to address the shortcomings of so-called historic MEM in these situations. We initially consider images from situations in which the model point- spread function is assumed to be three-dimensionally spatially invariant, and which approximates the real situation reasonably well. One technique lends itself well to this investigation: magnification mammography. MEM is offered as a way of breaking some of the conflicting performance requirements of this technique and we explore several new system possibilities with a working MEM system in place. A more complicated blurring function is encountered in linear tomography, which uses opposing movements of the image receptor and x-ray source to generate planar images through an object. Features outside a particular focal plane are smeared to such an extent that detail within the focal plane can be very difficult to detect. With appropriate modification of our MEM technique, processed images show a significant reduction to the blurring outside the focal plane.

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Gordon, Kerry. "Modelling and monitoring of medical time series." Thesis, University of Nottingham, 1986. http://eprints.nottingham.ac.uk/12369/.

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In this thesis we examine several extensions to the dynamic linear model framework, outlined by Harrison and Stevens (1976), in order to adapt these models for use in the on-line analysis of medical time series that arise from routine clinical settings. The situation with which we are most concerned is that where we are monitoring individual patients and wish to detect abrupt changes in the patient's condition as soon as possible. A detailed background to the study and application of dynamic linear models is given, and other techniques for time series monitoring are also discussed when appropriate. We present a selection of specific models that we feel may prove to be of practical use in the modelling and monitoring of medical time series, and we illustrate how these models may be utilized in order to distinguish between a variety of alternative changepoint-types. The sensitivity of these models to the specification of prior information is examined in detail. The medical background to the time series examined requires the development of models and techniques enabling us to analyze generally unequally-spaced time series. We test the performance of the resulting models and techniques using simulated data. We then attempt to build a framework for bivariate time series modelling, allowing, once more, for the possibility of unequally spaced data. In particular, we suggest mechanisms whereby causality and feedback may be introduced into such models. Finally, we report on several applications of this methodology to actual medical time series arising in various contexts including kidney and bone-marrow transplantation and foetal heart monitoring.

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Reeves, John A. F. "Longitudinal regression models for a study of age-related macular degeneration." Thesis, Keele University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267456.

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Morris, Andrew Paul. "Transmission tests of linkage and association using samples of nuclear families with at least one affected child." Thesis, University of Reading, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267416.

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Ekangaki, Abie. "An assessment of vaginal bleeding disturbances in women from different cultural groups using different contraceptive methods." Thesis, University of Southampton, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259504.

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Machin, David. "Statistical aspects of clinical trials." Thesis, University of Southampton, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.257667.

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Smith, Nicole Thomas. "Validation of criteria used to predict warfarin dosing decisions /." Diss., CLICK HERE for online access, 2004. http://contentdm.lib.byu.edu/ETD/image/etd427.pdf.

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Hsieh, Jui-Ying. "The Split Analysis for Multiple-Reader Multiple-Case Split-Plot Studies." Thesis, The George Washington University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10813369.

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One pathway for a new device to gain access to the marketplace requires demonstration that it is equivalent to, or substantially better than, a legally marketed device. To evaluate the equivalence of a medical imaging device, we propose measuring the intra- or inter-reader agreement in a reader study, where the clinicians (readers) make diagnoses on the medical images (cases) using both the new and old imaging devices. Such an endpoint, as well as its variance estimate, enable us to make a statistical inference on the equivalence of two devices. A method for multiple-reader multiple-case agreement analysis was presented in Gallas et al. (2016) for fully-crossed study designs, where every reader reads every case. In practice, having every reader read every case may be impossible when readers have a limited amount of time to participate in the study. One alternative study design is the split-plot study design, where both the readers and the cases are partitioned into a fixed number of groups, and each group of readers reads its own group of cases. In this thesis, we adapt the multiple-reader multiple-case agreement analysis method in Gallas et al. (2016) to analyze split-plot study designs, and propose a new variance estimator based on splitting the analysis across the groups. In each split sub-study, we compute an estimate, and then combine these estimates to obtain the final estimate for the full study. Our numerical studies show that the "split-analysis" variance estimator provides more accurate estimation of the variance of concordance measurements than the full-study-based method for unbalanced split-plot study designs.

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嚴嘉文. "中藥製劑處方與藥效的統計分析研究 : 婦科." HKBU Institutional Repository, 2011. http://repository.hkbu.edu.hk/etd_ra/1325.

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Yang, Li. "A comparison of unsupervised learning techniques for detection of medical abuse in automobile claims." California State University, Long Beach, 2013.

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Sonesson, Christian. "On statistical surveillance issues of optimality and medical applications /." Göteborg, Sweden : Stockholm : Statistical Research Unit, Göteborg University ; Almqvist & Wiksell International, 2003. http://catalog.hathitrust.org/api/volumes/oclc/53500706.html.

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Buchan, Iain Edward. "The development of a statistical computer software resource for medical research." Thesis, University of Liverpool, 2000. http://www.manchester.ac.uk/escholar/uk-ac-man-scw:71360.

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Medical research is often weakened by poor statistical practice, and inappropriate use of statistical computer software is part of this problem. The statistical knowledge that medical researchers require has traditionally been gained in both dedicated and ad hoc learning time, often separate from the research processes in which the statistical methods are applied. Computer software, however, can be written to flexibly support statistical practice. The work of this thesis was to explore the possibility of, and if possible, to create, a resource supporting medical researchers in statistical knowledge and calculation at the point of need. The work was carried out over eleven years, and was directed towards the medical research community in general. Statistical and Software Engineering methods were used to produce a unified statistical computational and knowledge support resource. Mathematically and computationally robust approaches to statistical methods were continually sought from current literature. The type of evaluation undertaken was formative; this included monitoring uptake of the software and feedback from its users, comparisons with other software, reviews in peer reviewed publications, and testing of results against classical and reference data. Large-scale opportunistic feedback from users of this resource was employed in its continuous improvement. The software resulting from the work of this thesis is provided herein as supportive evidence. Results of applying the software to classical reference data are shown in the written thesis. The scope and presentation of statistical methods are considered in a comparison of the software with common statistical software resources. This comparison showed that the software written for this thesis more closely matched statistical methods commonly used in medical research, and contained more statistical knowledge support materials. Up to October 31st 2000, uptake of the software was recorded for 5621 separate instances by individuals or institutions. The development has been self-sustaining. Medical researchers need to have sufficient statistical understanding, just as statistical researchers need to sufficiently understand the nature of data. Statistical software tools may damage statistical practice if they distract attention from statistical goals and tasks, onto the tools themselves. The work of this thesis provides a practical computing framework supporting statistical knowledge and calculation in medical research. This work has shown that sustainable software can be engineered to improve statistical appreciation and practice in ways that are beyond the reach of traditional medical statistical education.

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Sithole, Jabulani S. "Longitudinal data models for evaluating change in prescribing patterns." Thesis, Keele University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327702.

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Low, Chien-tat, and 劉振達. "Does place have an effect on the traditional Chinese medicine concept of body constitution?" Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/202380.

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Traditional Chinese Medicine (TCM) has long perceived the human body as a holistic system to sustain a healthy state. It emphasises that natural and social environments influence the physical and emotional balance of the human health. Contemporary health geography also recognises that place or environment is indispensable in studying population health. Both TCM and health geography share some similar views on the place effects on human health and wellbeing. However, the effects of TCM concept of body constitution and those of the living environment on the state of human health have not been supported with much empirical evidence. This study is an attempt to address three issues: a) Is there a place effect on body constitution? b) What are the possible individual or neighbourhood/community explanations behind the place effect? and c) Is there an association between body constitution and disease occurrence? The study uses multilevel logistic models to explore the evidence of place on body constitution. This study proposes to generalise “place” by means of an actual geographical division at the level of street block group for hypothesis testing through examining their covariance components in the multilevel analysis. The analysis also takes simultaneous accounts of both individual-level (gender, age, BMI, type of housing) and area-level (percent greenery, percent road surface, total road intersection, sky view factor, temperature, relative humidity, rainfall, and social deprivation index) characteristics to explain the geographical variation of body constitution. The bivariate choropleth mapping technique in cartographic design is employed to visualise and generalise the spatial correlation between body constitution and neighbourhood effects. The association between body constitution and disease prevalence are tested using the binary logistic regression analysis. The individual data of body constitution comprise a cohort of 3,277 patients attending the Centre of Integrated Health Management providing TCM services at the Kwong Wah Hospital. The attendance period was between 1/3/2009 and 31/12/2012 inclusive. The majority of patients was middle-aged Chinese (40 to 60) living within the remit of the Kowloon West Cluster. Despite limitations in the data, the findings unveil different views on human and environmental health pertaining to the Chinese population. It confirms that place does matter in the outcome of body constitution and the variability between neighbourhoods involves a dynamic interplay between individual and environmental factors. Specifically, the use of different geographic aggregation units (street block group and 800m buffer around each subject’s home location) to parameterise environmental factors brings out place characteristics of select body constitutions and exemplifies the modifiable areal unit problem in population health studies. This study is a first attempt to bring together health geography and body constitution theory to illuminate the interconnectedness between health, disease, personal attributes, and place. Because the TCM concept of body constitution is not an exact science and each individual can have more than one dominant body constitution which may change in time, it has been a challenge to resolve data issues and methodological constraints. Nonetheless, the study has contributed some interesting observations about TCM body constitution and its relationship with place.
published_or_final_version
Geography
Doctoral
Doctor of Philosophy

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Gould, Myles I. "Multilevel modelling of geographical variations in immunisation uptake." Thesis, University of Bristol, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296694.

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Sadkowsky, Krystian Reginald. "An analysis into geographic regional differences in cancer survival in Australia during 1982-1997 /." [St. Lucia, Qld.], 2001. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16944.pdf.

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Wen, Allisandra. "Global interaction patterns and disease transmission a case study of China /." Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B43786005.

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Dragset, Ingrid Garli. "Analysis of Longitudinal Data with Missing Values. : Methods and Applications in Medical Statistics." Thesis, Norwegian University of Science and Technology, Department of Mathematical Sciences, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9945.

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Missing data is a concept used to describe the values that are, for some reason, not observed in datasets. Most standard analysis methods are not feasible for datasets with missing values. The methods handling missing data may result in biased and/or imprecise estimates if methods are not appropriate. It is therefore important to employ suitable methods when analyzing such data. Cardiac surgery is a procedure suitable for patients suffering from different types of heart diseases. It is a physical and psychical demanding surgical operation for the patients, although the mortality rate is low. Health-related quality of life (HRQOL) is a popular and widespread measurement tool to monitor the overall situation of patients undergoing cardiac surgery, especially in elderly patients with naturally limited life expectancies [Gjeilo, 2009]. There has been a growing attention to possible differences between men and women with respect to HRQOL after cardiac surgery. The literature is not consistent regarding this topic. Gjeilo et al. [2008] studied HRQOL in patients before and after cardiac surgery with emphasis on differences between men and women. In the period from September 2004 to September 2005, 534 patients undergoing cardiac surgery at St Olavs Hospital were included in the study. HRQOL were measured by the self-reported questionnaires Short-Form 36 (SF-36) and the Brief Pain Inventory (BPI) before surgery and at six and twelve months follow-up. The SF-36 reflects health-related quality of life measuring eight conceptual domains of health [Loge and Kaasa, 1998]. Some of the patients have not responded to all questions, and there are missing values in the records for about 41% of the patients. Women have more missing values than men at all time points. The statistical analyses performed in Gjeilo et al. [2008] employ the complete-case method, which is the most common method to handle missing data until recent years. The complete-case method discards all subjects with unobserved data prior to the analyses. It makes standard statistical analyses accessible and is the default method to handle missing data in several statistical software packages. The complete-case method gives correct estimates only if data are missing completely at random without any relation to other observed or unobserved measurements. This assumption is seldom met, and violations can result in incorrect estimates and decreased efficiency. The focus of this paper is on improved methods to handle missing values in longitudinal data, that is observations of the same subjects at multiple occasions. Multiple imputation and imputation by expectation maximization are general methods that can be applied with many standard analysis methods and several missing data situations. Regression models can also give correct estimates and are available for longitudinal data. In this paper we present the theory of these approaches and application to the dataset introduced above. The results are compared to the complete-case analyses published in Gjeilo et al. [2008], and the methods are discussed with respect to their properties of handling missing values in this setting. The data of patients undergoing cardiac surgery are analyzed in Gjeilo et al. [2008] with respect to gender differences at each of the measurement occasions; Presurgery, six months, and twelve months after the operation. This is done by a two-sample Student's t-test assuming unequal variances. All patients observed at the relevant occasion is included in the analyses. Repeated measures ANOVA are used to determine gender differences in the evolution of the HRQOL-variables. Only patients with fully observed measurements at all three occasions are included in the ANOVA. The methods of expectation maximization (EM) and multiple imputation (MI) are used to obtain plausible complete datasets including all patients. EM gives a single imputed dataset that can be analyzed similar to the complete-case analysis. MI gives multiple imputed datasets where all dataset must be analyzed sepearately and their estimates combined according to a technique called Rubin's rules. Results of both Student's t-tests and repeated measures ANOVA can be performed by these imputation methods. The repeated measures ANOVA can be expressed as a regression equation that describes the HRQOL-score improvement in time and the variation between subjects. The mixed regression models (MRM) are known to model longitudinal data with non-responses, and can further be extended from the repeated measures ANOVA to fit data more sufficiently. Several MRM are fitted to the data of cardiac surgery patients to display their properties and advantages over ANOVA. These models are alternatives to the imputation analyses when the aim is to determine gender differences in improvement of HRQOL after surgery. The imputation methods and mixed regression models are assumed to handle missing data in an adequate way, and gives similar analysis results for all methods. These results differ from the complete-case method results for some of the HRQOL-variables when examining the gender differences in improvement of HRQOL after surgery.

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Martin, Stacey L. "Cartography, Discourse, and Disease: How Maps Shape Scientific Thought about Disease." unrestricted, 2005. http://etd.gsu.edu/theses/available/etd-04222005-094353/.

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Thesis (M.A.)--Georgia State University, 2005.
Title from title screen. Jeremy Crampton, committee chair; Michael Eriksen, Dona Stewart, committee members. Electronic text (94 p. : ill., maps (some col.)) : digital, PDF file. Description based on contents viewed July 10, 2007. Includes bibliographical references (p. 88-94).

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Almudaris, Sami M. "Measuring Accessibility to Primary Care Physicians in the Nashville Metropolitan Statistical Area." TopSCHOLAR®, 2011. http://digitalcommons.wku.edu/theses/1125.

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The growing concern for the shortage of primary care physicians (PCPs) prompted a government legislation to designate areas where shortage in the delivery of primary care services occurs. The implemented systems (e.g., HPSA, MUA, and MUP) analyze utilization of health services within confined administrative units and fail to account for spatial interactions that occur across administrative borders. This research examines the spatial accessibility to PCPs and the underlying demographic and socioeconomic settings. With the Nashville Metropolitan Statistical Area (MSA) as a study area, this study utilized data from the U.S. Census 2000 and 2010, as well as the known locations of (PCPs) collected in 2010. Geographic Information Systems (GIS) provided the tools by which the processing and analysis of the data was carried out. Specifically, network analysis was applied to estimate travel time and service area coverage. A Two-Step Floating Catchment Area (2SFCA) method was implemented to measure spatial accessibility to PCPs. This method was applied to measure accessibility at the level (census block) that most accurately represents the spatial population of the Nashville MSA. In addition, this research implemented several distance-decay functions in addition to the dichotomous function of the standard 2SFCA method. This research has found that the majority of the population residing in the Nashville MSA enjoyed good spatial accessibility to PCPs. However, the highest percentages of those resided in areas of low accessibility were located in periphery rural areas as well as isolated areas poorly connected to the roadway network due to certain physical barriers such as lakes and streams. Moreover, this research has found that, in general, non-spatial factors intensified the most where there was good accessibility to PCPs.

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Altonen, Brian Lee. "Asiatic cholera and dysentery on the Oregon Trail : a historical medical geography study." PDXScholar, 2000. https://pdxscholar.library.pdx.edu/open_access_etds/4305.

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Two disease regions existed on the Oregon Trail. Asiatic cholera impacted the Platte River flood plain from 1849 to 1852. Dysentery developed two endemic foci due to the decay of buffalo carcasses in eastern and middle Nebraska between 1844 and 1848, but later developed a much larger endemic region west of this Great Plains due to the infection of livestock carcasses by opportunistic bacteria. This study demonstrates that whereas Asiatic cholera diffusion along the Trail was defined primarily by human population features, topography, and regional climate along the Platte River flood plain, the distribution of opportunistic dysentery along the Trail was defined primarily by human and animal fitness in relation to local topography features. By utilizing a geographic interpretation of disease spread, the Asiatic cholera epidemic caused by Vibrio cholerae could be distinguished from the dysentery epidemic caused by one or more species of Salmonella or Campylobacter. In addition, this study also clarifies an important discrepancy popular to the Oregon Trail history literature. "Mountain fever," a disease typically associated with Rocky Mountain Spotted Fever, was demonstrated to be cases of fever induced by the same bacteria responsible for opportunistic dysentery. In addition, several important geographic methods of disease interpretations were used for this study. By relating the epidemiological transition model of disease patterns to the early twentieth century sequent occupance models described in numerous geography journals, a spatially- and temporally-oriented disease model was produced applicable to reviews of disease history, a method of analysis which has important applications to current studies of disease patterns in rapidly changing rural and urban population settings.

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Boyer, Stacy Bingham. "The Implementation of Refugee Health Policies and Services in Virginia's Local Health Districts." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/36414.

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In 1997, the Virginia Refugee Health Program coordinated a protocol and reimbursement structure to encourage health departments to perform initial health screenings on refugees settling in the Commonwealth by establishing four recommended levels of assessment. This thesis is concerned with these initial health-related services provided to refugees by Virginia's health departments, the quality of these services, and how they vary from one district to another. For this study, I interviewed health department staff representing 13 of Virginia's 19 districts that rendered health screenings in 2000. Information such as the level of assessment provided, and the types of procedures and services offered were the main foci of the interviews. I found that of the 13 districts, three (the cities of Alexandria and Virginia Beach, and Prince William County) offer only the required minimum to refugees. The variations I discovered in the services that health districts provide suggest, conceptually, the workings of both "structure" and "agency." Each health department is formally and informally structured in terms of staffing, services, and resources in accordance with its individual needs and initiatives. The structure of current funding at both the state and local level acts to inhibit some health districts from providing all four levels of assessment. In addition, human agency in the form of personal interest in meeting refugee's health needs as well as district collaboration with local resettlement agencies, also plays an important role in the extent of refugee services rendered.
Master of Science

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38

Gater, Thomas. "Pharmaceutical Security in South Africa: Law and Medical Geopolitics." Thesis, University of the Western Cape, 2008. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_5273_1274376650.

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The study focuses on the political and economic geographies of pharmaceutical delivery. In 1997 the South African government passed the Medicines and Related Substances Control Amendment Act, sparking outrage from both the local and international pharmaceutical industry, and resulting in court action in 2001. The industry believed that South Africa was in breach of its obligations under international intellectual property law. Those fighting for pharmaceutical security hoped the court case would be a &lsquo
landmark&rsquo
in the global campaign for equitable access to medicines. This investigation seeks to analyse the domestic and international legacy of the court action. The inquiry takes its significance from the high prevalence rates of treatable diseases and the need for pharmaceutical security in South Africa and its neighbouring African countries. The absence of a sustainable international medicines delivery system is a global political, economic and moral failure. A solution is required that balances the positive productive forces of the market with a philosophy of justice and equity.

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Hernandez, Monique Nicole. "A Spatial Analysis of Colorectal Cancer in Miami-Dade County." Scholarly Repository, 2008. http://scholarlyrepository.miami.edu/oa_dissertations/99.

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This dissertation explores the spatial patterns and place-based characteristics of colorectal cancer (CRC) late stage incidence and CRC-specific mortality in Miami-Dade County. Because CRC is the second leading cause of death among all cancers and is almost 90 percent preventable through medical screenings, investigations of CRC disparities across groups and communities are extremely relevant in the fight against cancer. This paper analyzes the geographic distribution of CRC cases in Miami-Dade County between two periods, 1988-1992 and 1998-2002 to: a) identify significant "hot spots" or clusters of disease; b) investigate associations of CRC patterns with neighborhood level characteristics such as socio-economic status, race/ethnicity, and poverty; and c) explore the policy implications of the spatial trends identified for the disease, with particular reference to the Welfare Reform Act of 1996. This dissertation analyzes data from the Florida Cancer Data Registry and tract level U.S. Census data, to identify the spatial distribution of CRC and study its relation to place-based variables using Geographic Information Systems (GIS) and spatial statistical modeling. Identifying spatial clusters of disease can assist in targeting public health interventions and improving social service delivery, particularly for uninsured populations. Identifying communities facing greater obstacles to screenings and quality medical care through the use of spatial analysis is an effort to mitigate these barriers while simultaneously providing empirically based evidence linking neighborhood-level social and economic conditions to health disparities.

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黃式鈞 and Sik-kwan Francis Wong. "Outcome of a web-based statistic laboratory for teaching and learning of medical statistics." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B43251687.

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Woods, Tonya M. "Extracting meaningful statistics for the characterization and classification of biological, medical, and financial data." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/53857.

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This thesis is focused on extracting meaningful statistics for the characterization and classification of biological, medical, and financial data and contains four chapters. The first chapter contains theoretical background on scaling and wavelets, which supports the work in chapters two and three. In the second chapter, we outline a methodology for representing sequences of DNA nucleotides as numeric matrices in order to analytically investigate important structural characteristics of DNA. This methodology involves assigning unit vectors to nucleotides, placing the vectors into columns of a matrix, and accumulating across the rows of this matrix. Transcribing the DNA in this way allows us to compute the 2-D wavelet transformation and assess regularity characteristics of the sequence via the slope of the wavelet spectra. In addition to computing a global slope measure for a sequence, we can apply our methodology for overlapping sections of nucleotides to obtain an evolutionary slope. In the third chapter, we describe various ways wavelet-based scaling may be used for cancer diagnostics. There were nearly half of a million new cases of ovarian, breast, and lung cancer in the United States last year. Breast and lung cancer have highest prevalence, while ovarian cancer has the lowest survival rate of the three. Early detection is critical for all of these diseases, but substantial obstacles to early detection exist in each case. In this work, we use wavelet-based scaling on metabolic data and radiography images in order to produce meaningful features to be used in classifying cases and controls. Computer-aided detection (CAD) algorithms for detecting lung and breast cancer often focus on select features in an image and make a priori assumptions about the nature of a nodule or a mass. In contrast, our approach to analyzing breast and lung images captures information contained in the background tissue of images as well as information about specific features and makes no such a priori assumptions. In the fourth chapter, we investigate the value of social media data in building commercial default and activity credit models. We use random forest modeling, which has been shown in many instances to achieve better predictive accuracy than logistic regression in modeling credit data. This result is of interest, as some entities are beginning to build credit scores based on this type of publicly available online data alone. Our work has shown that the addition of social media data does not provide any improvement in model accuracy over the bureau only models. However, the social media data on its own does have some limited predictive power.

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Reddy, Sumanth Gopala. "Medical tourism in India: an exploratory study." Diss., Kansas State University, 2013. http://hdl.handle.net/2097/16193.

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Doctor of Philosophy
Department of Geography
Bimal K. Paul
Medical tourism comprises a phenomenon where over five million patients a year are traveling across international borders to obtain various forms of health care. Most of these patients travel from developed countries to developing countries, seeking highly invasive medical treatments to less invasive and recreational medical procedures. By the year 2012, the medical tourism industry generated over $100 billion with over 50 countries making it a priority in trade for their country. With active government promotions, India has become one of the leading destinations for medical tourism. The objective of this research was to answer the questions: 1) how do the attitudes and behaviors of patients towards the concept of medical tourism influence their decision to become a medical tourist; 2) why do medical tourists seek treatment in India; and 3) what are the issues and challenges they face before coming to India as well as while in India. Interviews of thirty-four foreign patients were conducted in six sites spread across the South-Indian cities of Bangalore, Hyderabad, and Chennai which revealed useful information in addressing the research objectives. The three most important reasons that these medical tourists chose India for their treatments were: 1) the high quality of the doctors and medical facilities in India, 2) the affordable cost of treatments, and 3) the availability of specific treatments that might not have been available in their home countries. Patients also researched the topic thoroughly before they came to India. Knowledge was gained primarily from the Internet, print media, television shows and friends. Overall, the patients had very positive attitudes towards medical tourism. Most of them felt that they could get treatment because of their positive opinion on medical tourism, their ability to get treatment if they desired, and support from their families and loved ones.

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Kutch, Libbey. "An Investigation of the Relationship between HIV and Prison Facilities in Texas: The Geographic Variation and Vulnerable Neighborhood Characteristics." Thesis, University of North Texas, 2011. https://digital.library.unt.edu/ark:/67531/metadc84234/.

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Previous research suggests that prisons may be fueling the spread of HIV infection in the general population. In 2005, the HIV rate was more than 2.5 times higher in US prison populations. Environmental factors in prisons such as illicit drug use and unprotected sexual activities can be conducive for HIV transmission. Because the vast majority of prison inmates are incarcerated for less than three years, transmission of HIV between prison inmates and members of the general population may occur at a high rate. The environment in which an individual lives and the entities that comprise it affect the health of that person. Thus the location of prisons within communities, as well as socio-demographic characteristics may influence the geography of HIV infection. HIV surveillance data, obtained from the Texas Department of State Health Services, were used to investigate the relationship between the location of prison units in Texas and HIV infection rates in the surrounding zip codes. The results suggest that HIV prevalence rates are higher among geographic areas in close proximity to a prison unit. With continued behavioral risks and low treatment adherence rates among individuals infected with HIV, there is a possibility of increased HIV prevalence. Vulnerable places, locations with higher HIV prevalence, should be targeted for resource allocation and HIV prevention and care service. This study illustrates the importance of spatial analysis of places vulnerable to increased HIV prevalence in creating more effective public health prevention strategies and interventions.

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Henderson, Neil James Kerr. "Extending the clinical and economic evaluations of a randomised controlled trial the IONA study /." Connect to e-thesis, 2008. http://theses.gla.ac.uk/418/.

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Thesis (Ph.D.) - University of Glasgow, 2008.
Ph.D. thesis submitted to the Department of Statistics, Faculty of Information and Mathematical Sciences, University of Glasgow, 2008. Includes bibliographical references. Print version also available.

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Drymoussis, Michael. "Globalisation and commercialisation of healthcare services : with reference to the United States and United Kingdom." Thesis, University of Sussex, 2014. http://sro.sussex.ac.uk/id/eprint/61483/.

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The thesis seeks to interrogate historically the relationship between multinational healthcare service companies and states in the pursuit of market-oriented reforms for healthcare. It constitutes a critical reading of the idea of globalisation as a concept with substantive explanatory value to analyse the causal role of multinational service firms in a commercial transformation in national healthcare service sectors. It analyses the development and expansion of commercial (for-profit) healthcare service provision and financing in the healthcare systems of OECD countries. The hospital and health insurance sectors in the US and UK are analysed as case studies towards developing this critical reading from a more specific national setting. The thesis contributes to developing a framework for analysing the emergence of an international market for trade in healthcare services, which is a recently emerging area of research in the social sciences. As such, it uses an interdisciplinary approach, utilising insights from health policy and international political economy. The research entails a longitudinal study of secondary and primary sources of qualitative data broadly covering the period 1975-2005. I have also made extensive use of quantitative data to illustrate key economic trends that are relevant to the changes in the particular healthcare services sectors analysed. The research finds a substantive shift in the mixed economy of healthcare in which commercial healthcare service provision and financing are increasing. However, while the internationalisation of healthcare service firms is a key element in helping to drive some of this change, the changes are ultimately highly dependent on state-level decision making and regulation. In this context, the thesis argues that globalisation presents an inadequate and potentially misleading conceptual framework for analysing these changes without a historical grounding in the particular developments of national and international markets for healthcare services.

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Eklund, Anders. "Computational Medical Image Analysis : With a Focus on Real-Time fMRI and Non-Parametric Statistics." Doctoral thesis, Linköpings universitet, Medicinsk informatik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-76120.

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Functional magnetic resonance imaging (fMRI) is a prime example of multi-disciplinary research. Without the beautiful physics of MRI, there wouldnot be any images to look at in the first place. To obtain images of goodquality, it is necessary to fully understand the concepts of the frequencydomain. The analysis of fMRI data requires understanding of signal pro-cessing, statistics and knowledge about the anatomy and function of thehuman brain. The resulting brain activity maps are used by physicians,neurologists, psychologists and behaviourists, in order to plan surgery andto increase their understanding of how the brain works. This thesis presents methods for real-time fMRI and non-parametric fMRIanalysis. Real-time fMRI places high demands on the signal processing,as all the calculations have to be made in real-time in complex situations.Real-time fMRI can, for example, be used for interactive brain mapping.Another possibility is to change the stimulus that is given to the subject, inreal-time, such that the brain and the computer can work together to solvea given task, yielding a brain computer interface (BCI). Non-parametricfMRI analysis, for example, concerns the problem of calculating signifi-cance thresholds and p-values for test statistics without a parametric nulldistribution. Two BCIs are presented in this thesis. In the first BCI, the subject wasable to balance a virtual inverted pendulum by thinking of activating theleft or right hand or resting. In the second BCI, the subject in the MRscanner was able to communicate with a person outside the MR scanner,through a virtual keyboard. A graphics processing unit (GPU) implementation of a random permuta-tion test for single subject fMRI analysis is also presented. The randompermutation test is used to calculate significance thresholds and p-values forfMRI analysis by canonical correlation analysis (CCA), and to investigatethe correctness of standard parametric approaches. The random permuta-tion test was verified by using 10 000 noise datasets and 1484 resting statefMRI datasets. The random permutation test is also used for a non-localCCA approach to fMRI analysis.

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Huitfeldt, Anders. "Emulation of Target Trials to Study the Effectiveness and Safety of Medical Interventions." Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:23205172.

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Ideally, clinical guidelines would be informed by well-designed randomized experiments. However, it is generally not possible to conduct a randomized trial for every clinically relevant decision. Decision makers therefore often have to rely on observational data. Guidelines that rely on observational data due to the absence of randomized trials benefit when the analysis mimics the analysis of a hypothetical target trial. This can be achieved by explicitly formulating the protocol of the target trial, and thoroughly discussing the feasibility of the conditions that must be met in order to validly emulate the target trial using observational data. In chapter one, we discuss the emulation of trials that compare the effects of different timing strategies, that is, strategies that vary the frequency of delivery of a medical intervention or procedures, and provide an application to surveillance for colorectal cancer. In chapter two, we discuss a study design that attempts to avoid bias by comparing initiators of the treatment of interest with initiators of an “active comparator” that is believed to be inactive for the outcome, in order to emulate a randomized trial that compares the treatment of interest with an inactive comparator. In chapter three, we describe a new method that combines randomized trial data and external information to emulate a different target trial. We apply this method to a randomized trial of postmenopausal hormone therapy in order to emulate a trial of a joint intervention on hormone therapy and statin therapy.

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Zhang, Lin Tubbs Jack Dale. "Semiparametric AUC regression for testing treatment effect in clinical trial." Waco, Tex. : Baylor University, 2008. http://hdl.handle.net/2104/5237.

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Xu, Peiheng 1965. "The effect of utilizing spatial information for brain image segmentation /." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=81458.

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This thesis addresses several brain MRI segmentation methods including three methods of using normal distributions, similar methods using t-distributions and a new method using MCLUST software packages. The main purpose of this thesis is to try to improve current brain image segmentation methods and reduce the long computing time with satisfactory results. The methodology consists in applying histogram analysis for the initialization of parameters, using Simpson's rule for the approximation of numerical integration and describing methods of skull stripping and neighborhood information encoding. The two most significant contributions are suggestions for speeding up current methods and a newly proposed method that ignores spatial information for parameter estimation. Potential future work is proposed at the end.

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Chapman, Joanne Shirley. "Statistical methods for gamma mixtures of proportional hazards survival models." Thesis, Lancaster University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340567.

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Dissertations / Theses on the topic 'Medical statistics Medical geography'

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