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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
431

PARAMETRIC ESTIMATION IN COMPETING RISKS AND MULTI-STATE MODELS

Lin, Yushun 01 January 2011 (has links)
The typical research of Alzheimer's disease includes a series of cognitive states. Multi-state models are often used to describe the history of disease evolvement. Competing risks models are a sub-category of multi-state models with one starting state and several absorbing states. Analyses for competing risks data in medical papers frequently assume independent risks and evaluate covariate effects on these events by modeling distinct proportional hazards regression models for each event. Jeong and Fine (2007) proposed a parametric proportional sub-distribution hazard (SH) model for cumulative incidence functions (CIF) without assumptions about the dependence among the risks. We modified their model to assure that the sum of the underlying CIFs never exceeds one, by assuming a proportional SH model for dementia only in the Nun study. To accommodate left censored data, we computed non-parametric MLE of CIF based on Expectation-Maximization algorithm. Our proposed parametric model was applied to the Nun Study to investigate the effect of genetics and education on the occurrence of dementia. After including left censored dementia subjects, the incidence rate of dementia becomes larger than that of death for age < 90, education becomes significant factor for incidence of dementia and standard errors for estimates are smaller. Multi-state Markov model is often used to analyze the evolution of cognitive states by assuming time independent transition intensities. We consider both constant and duration time dependent transition intensities in BRAiNS data, leading to a mixture of Markov and semi-Markov processes. The joint probability of observing a sequence of same state until transition in a semi-Markov process was expressed as a product of the overall transition probability and survival probability, which were simultaneously modeled. Such modeling leads to different interpretations in BRAiNS study, i.e., family history, APOE4, and sex by head injury interaction are significant factors for transition intensities in traditional Markov model. While in our semi-Markov model, these factors are significant in predicting the overall transition probabilities, but none of these factors are significant for duration time distribution.
432

財產稅之租稅資本化:台北都市化地區之實證研究

李中文 Unknown Date (has links)
在其他條件不變時,房屋的現值是居住者將預期該棟房屋在未來各期所能提供的服務價值,扣除預期未來各期所需負擔之財產稅後,將淨服務價值按折現率加以折現後之價值。租稅資本化問題即為研究財產稅折現進入房價的比率,但是,公共支出與有效財產稅率之間的潛在關連與房屋服務價值的設算方式是相關研究的最大限制,本文採用Palmon and Smith (1998b)的修正後的Capitalization Model,以預測租金加上管理費設算房屋所提供的服務價值,配合台北市與台北縣的買屋抽樣資料,估計台北都市化地區的財產稅資本化比率,幾乎所有的實證結果都顯示存在著過度資本化的情形,探究可能的原因,資料的誤差以及相關變數的遺漏都有可能導致過度資本化的情形。若是資料誤差不大時,購屋者的資訊不完全與房價被高估而使有效財產稅率過低也許是造成過度資本化的真正原因。 / All other things being equal, the value of a house equals the present value of the rental flow minus the present value of the property tax flow. The objective of this study is to estimate the degree of property tax capitalization of the Taipei urbanized area. In fact, there are two main limitations on this issue—the potential correlation between local public expenditures and effective property tax rate, and the method in computing the value of housing service. We apply the modified capitalization model established by Palmon and Smith (1998b) and the idea that the values of housing services equal the estimates of rental prices plus the management fees to estimate the degree of capitalization. Our result shows that there is over capitalization in Taipei urbanized area and that the degree of capitalization reported here is much greater than those from past studies. Although such over-capitalization result may be caused by sample errors and missing variables, it can be argued that, if the sample-error problem isn’t severe, incomplete information and under-estimated effective property tax rates should take the blame for this.
433

A Longitudinal Study of Diabetes Mellitus : With Special Reference to Incidence and Prevalence, and to Determinants of Macrovascular Complications and Mortality

Jansson, Stefan P.O. January 2014 (has links)
Objectives. To investigate diabetes prevalence, incidence, mortality trends, the effects of hyperglycaemia and blood pressure, diabetes and hypertension treatment, and the effect of screening detection on total and cardiovascular disease (CVD), myocardial infarction (MI) and stroke incidence. Study population and methods. Between 1972 and 2001 all patients with diabetes, some detected clinically and some by case-finding procedures (screening), were entered in a diabetes register at Laxå Primary Health Care Center in Sweden. The register included information on medical treatment and laboratory data as well as information on mortality and morbidity from National Registers. The register was supplemented with five non-diabetic subjects, matched to each diabetes patients by age, sex, and year of detection. Results. During the study period 776 new diabetes cases was found, 36 type 1 diabetes mellitus and 740 type 2 diabetes mellitus. Age standardised incidence and prevalence rates for type 1 and type 2 diabetes did not increase over time. Diabetic patients had 17% higher mortality rate than non-diabetic persons, 22% in women and 13% in men. The corresponding over-mortality in CVD was 33%, 41% in women and 27% in men. CVD mortality decreased across time in non-diabetic subjects and in diabetic men but not in diabetic women. Results regarding coronary heart disease (CHD) were similar. CVD incidence increased with fasting blood glucose (FBG), body mass index (BMI), mean arterial blood pressure (MABP), and decreased with metformin treatment and sulfonylurea. Myocardial infarction incidence increased with FBG, BMI and MABP, and decreased with metformin treatment. Stroke incidence increased with MABP. There was no difference in prognoses between those detected by screening or clinically. Conclusions. Diabetes prevalence and incidence did not change over time. The over-mortality according to diabetes was moderate. CVD and MI during follow up were negatively affected by hypertension and hyperglycaemia, and positively by pharmacological diabetic treatment. For stroke no pharmacological protective effect was seen. Screening did not improve prognosis.
434

Incidence of Childhood Diabetes in Children Aged Less than 15 Years and Its Clinical and Metabolic Characteristics at the Time of Diagnosis: Data from the Childhood Diabetes Registry of Saxony, Germany

Galler, Angela, Stange, Thoralf, Müller, Gabriele, Näke, Andrea, Vogel, Christian, Kapellen, Thomas, Bartelt, Heike, Kunath, Hildebrand, Koch, Rainer, Kiess, Wieland, Rothe, Ulrike 18 March 2014 (has links) (PDF)
Aims: The Childhood Diabetes Registry in Saxony, Germany, examined the incidence and metabolic characteristics of childhood diabetes. Methods: In the federal state of Saxony, newly diagnosed cases of diabetes in children and adolescents aged less than 15 years were registered continuously from 1999 until 2008. Family history, date of diagnosis, clinical and laboratory parameters were obtained. Reported cases were ascertained by public health departments as an independent data source and verified using the capture- recapture method. Results: A total of 865 children and adolescents with newly diagnosed diabetes were registered in Saxony. About 96% of them were classified as having type 1 diabetes, 0.6% had type 2 diabetes, 2.4% had maturity-onset diabetes of the young (MODY), and 1.4% had other types of diabetes. The age-standardized incidence rate of type 1 diabetes was estimated at 17.5 per 100,000 children per year. Completeness of ascertainment as calculated by the capture-recapture method amounted to 93.6%. At the time of diagnosis, 27.1% of children with type 1 diabetes had ketoacidosis, 1.5% had a blood pH <7.0, and 1.1% were unconscious. Conclusion: The registry provided data about the incidence rates and clinical presentation of childhood diabetes in a defined German population. We observed higher incidence rates compared to previous surveys. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
435

Senzitivnost i specifičnost definicije slučaja velikog kašlja / Sensitivity and specificity of case definition for pertussis

Ristić Mioljub 24 March 2016 (has links)
<p>Uprkos rezultatima postignutih imunizacijom, veliki ka&scaron;alj je i danas vodeći uzrok smrti među zaraznim bolestima protiv kojih se sprovodi imunizacija. Postojanje različitih vrsta nadzora, prisutnih nedostataka laboratorijske dijagnostike oboljenja, slabosti u dostupnim definicijama slučaja velikog ka&scaron;lja i neprepoznavanje oboljenja, otežavaju realno sagledavanje opterećenja velikim ka&scaron;ljem i poređenje postignutih rezultata u različitim zemljama. Postojeće definicije slučaja velikog ka&scaron;lja nisu prihvatljive u svim uzrastima. Cilj istraživanja je bio da se na reprezentativnom uzorku Grada Novog Sada utvrdi: stopa incidencije velikog ka&scaron;lja tokom jedne godine savremenog nadzora; senzitivnost i specifičnost definicija slučaja velikog ka&scaron;lja, datih od strane Globalne pertusis inicijative za tri uzrasne grupe. U istraživanje je uključeno 213 ispitanika pacijenata iz sentinelnog nadzora nad velikim ka&scaron;ljem Doma zdravlja Novi Sad i 107 ispitanika pacijenata iz hospitalnog nadzora sa iste teritorije koji su ispunjavali predložene definicije slučaja za tri uzrasne grupe (0-3 meseca; 4 meseca-9 godina života; 10 godina i stariji). Podaci za istraživanje dobijeni su popunjavanjem anketnog upitnika. Laboratorijsko testiranje sumnji na veliki ka&scaron;alj sprovedeno je u Centru za mikrobiologiju Instituta za javno zdravlje Vojvodine. Kod pacijenata sa ka&scaron;ljem u trajanju do 21 dan testiranje je vr&scaron;eno upotrebom PCR metoda, a kod pacijenata sa ka&scaron;ljem u trajanju vi&scaron;e od 21 dan, dokazivanje oboljenja vr&scaron;eno je upotrebom ELISA IgA i IgG serolo&scaron;kih testova. Potvrđenim slučajem velikog ka&scaron;lja smatran je pacijent sa ispunjenom definicijom slučaja oboljenja i laboratorijskom potvrdom oboljenja, PCR ili ELISA testom. Procenjena stopa incidencije velikog ka&scaron;lja u Novom Sadu je 237,7/100.000, a stopa incidencije hospitalizovanih u Novom Sadu je 16,4/100.000. Najvi&scaron;e stope incidencije velikog ka&scaron;lja u sentinelnom nadzoru registruju se u uzrastu 10-14, a u hospitalnom u uzrastu od 7 do 9 godina. Senzitivnost, specifičnost i stepen verovatnoće pozitivnog rezultata testiranog simptoma/znaka iz predloženih definicija slučaja se razlikuju po uzrastima i po pojedinim simptomima/znacima. Predložene definicije slučaja u uzrastima od 4 meseca do 9 godina i u uzrastu od 10 godina i starijih imaju veću verovatnoću otkrivanja obolelih u hospitalnom u odnosu na sentinelni nadzor za pojedine simptome/znakove. Budući da je tokom istraživanja u sentinelnom nadzoru oboljenje potvrđeno kod svakog petog, a u hospitalnom kod svakog drugog testiranog pacijenta, predložene definicije slučaja se mogu koristiti u nadzoru nad velikim ka&scaron;ljem.</p> / <p>Despite all results achieved by immunization, pertussis is still the leading cause of death among vaccine preventable diseases. Different types of surveillance and laboratory confirmation of pertussis, weakness of existing case definitions for pertussis and broad spectrum clinical manifestation of disease, complicate overview of disease and result comparison of surveillance in different countries. The current pertussis case definition is not acceptable for all age groups of patients. The aim of this research was to determine: the pertussis incidence rate in population of Novi Sad during one year of modern surveillance; the sensitivity and specificity of clinical case definition for pertussis, given by the Global Pertussis Initiative for three age groups, with a representative sample of population in the City of Novi Sad. 213 patients from sentinel surveillance of pertussis Novi Sad Health Centre and 107 hospitalized patients from Novi Sad, who fulfilled criteria of case definition proposed for the three age groups (0-3 months, 4 months-9 years; 10 years of age and older), were included in the research. Research data obtained from a questionnaire. Laboratory testing of suspected cases were conducted at the Centre for Microbiology, Institute of Public Health of Vojvodina. For patients with coughing less than 21 days PCR method was used, and for patients with cough lasting more than 21 days, laboratory confirmation of disease was performed using ELISA IgA and IgG serological tests. Confirmed case of pertussis consider to be a patient with symptoms/signs according to proposed case definition and with laboratory confirmation of the pertussis, PCR or ELISA. Estimated incidence rate of pertussis for population in the city of Novi Sad was 237.7/100,000, and the pertussis incidence rate in hospitalized patient in Novi Sad was 16.4/100,000. The highest incidence rate of pertussis in the sentinel surveillance was registered in the age group 10-14 and in the hospital surveillance in the group 7 to 9 years of age. The values of sensitivity, specificity and positive likelihood ratio of symptoms/signs from the proposed case definition were calculated and they different by age and by certain symptoms/signs from proposed case definition. Certain symptoms/signs of the proposed case definition have a higher probability of detection among patients aged 4 months to nine, and at the age of ten year and older, in the hospital versus those in sentinel surveillance for pertussis. During research from the patients who were tested in sentinel surveillance every fifth was laboratory confirmed case and in the hospital surveillance every second patient was confirmed case, so the proposed case definitions can be used in the surveillance of pertussis.</p>
436

Vliv metapopulační struktury a faktorů prostředí na populační biologii netýkavky Impatiens noli-tangere napadené padlím Podosphaera balsaminae / Effect of metapopulation structure and environmental factors on population biology of Impatiens noli-tangere infected by powdery mildew Podosphaera balsaminae

Chalupníková, Jana January 2015 (has links)
Studies performed on natural pathosystems revealed that the spatial structure of the metapopulation plays an important role in the development and spread of disease; phytopathological experimental studies have also revealed a significant effect of climatic factors on the presence of the disease (incidence) and the level of infection (prevalence) in populations. The aim of this study was to explore a natural pathosystem from both sides at the same time and to see which local and spatial environmental factors influence the development of pathosystem. Study focuses on population biology of natural pathosystem Podospaera balsaminae - Impatiens noli-tangere, which has not been investigated yet. In the study area (between the city Sázava (Benešov district) and village Vlkančice) host populations occurred in 78 (64 of them were infected) in 2013 and 82 populations (61 of them were infected) in 2014. Size of host populations had the strongest effect to incidence and prevalence of disease in the pathosystem. In larger populations, the disease occurred more often, developed faster and was higher. The rate of spread of the pathogen territory and the rate of population host connectivity had also strong effect. The abundance of pathogen in the studied area and the level of connectivity of host populations also...
437

Statistická analýza přežití a incidenční funkce / Statistická analýza přežití a incidenční funkce

Djordjilović, Vera January 2011 (has links)
Competing risks occur often in survival analysis. In present work, we study different ap- proaches to modeling competing risks data and use examples to illustrate the most impor- tant results. In the competing risks setting it is often of interest to calculate the cumulative incidence of a specific event. We first study non-parametric estimation and then present three approaches to regression modeling. We use simple numerical example to demonstrate the use of non-parametric methods and perform analysis of real data from Stanford Heart Transplant Program to illustrate and compare the chosen regression models.
438

Daně ze spotřeby a tržní ceny: interakce a efekty / Consuption Taxes and Market Prices: Interaction and Effects

Křiklava, Eduard January 2009 (has links)
The subject of this thesis is interaction between market prices and consumption taxes. The thesis contains analysis of influence of consumption taxes on market prices of five chosen goods, monitors possible causes, observes and quantifies the amount of additionally imposed tax, which is beard by consumer or producer of the good. The analysis of consumption taxes influence on market prices is performed by methods of correlation and regression analysis. Analyzed products are petrol "natural 95" (unleaded), diesel oil, cigarettes Petra and Sparta, dark rum and beer. Prices of these goods are monitored by Czech Statistical Office. First part of this thesis contains mostly theoretical introduction and impact theory of taxes. Second part deals with particular consumption taxes and their short-term impact. The third part of this thesis contains the statistical analysis.
439

Incidência e prevalência da Papilomatose Laríngea no Estado de São Paulo

Mercuri, Gustavo January 2019 (has links)
Orientador: Regina Helena Garcia Martins / Resumo: Mercuri G. Incidência e Prevalência da Papilomatose Laríngea no Estado de São Paulo [dissertação]. Botucatu, SP: Faculdade de Medicina de Botucatu, Universidade Estadual Paulista; 2019. Introdução: A papilomatose respiratória recorrente ou papilomatose laríngea recorrente é a neoplasia benigna da laringe causada pelo Papiloma Vírus Humano, caracterizando-se pela presença de lesões proliferativas exofíticas recorrentes. A ausência de tratamento curativo, os custos relacionados ao diagnóstico, prevenção e tratamento das doenças causadas pelo HPV apresentam importante impacto econômico em todo mundo. No entanto, a falta de dados epidemiológicos nacionais, quanto à incidência e prevalência da papilomatose laríngea no Brasil não nos permite analisar o comportamento da doença em nossa população, bem como os benefícios da vacinação. Objetivo: Estimar a incidência e a prevalência da Papilomatose Laríngea no Estado de São Paulo. Métodos: Estudo populacional que objetivou levantar todos os casos diagnosticados de Papilomatose Laríngea do Estado de São Paulo, considerando os principais centros de diagnóstico desta enfermidade. Foram mapeados e selecionados os principais serviços de residência e especialização em Otorrinolaringologia do Estado de São Paulo, a partir dos dados fornecidos pela Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial (ABORL-CCF). Através do preenchimento de um questionário obtivemos os dados para estimar a prevalência e a incidência mínimas p... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Mercuri G. Incidence and Prevalence of Laryngeal Papillomatosis in São Paulo State [thesis]. Botucatu, SP: Faculty of Medicine of Botucatu, Universidade Estadual Paulista; 2019. Introduction: Recurrent respiratory papillomatosis or recurrent laryngeal papillomatosis is a benign laryngeal neoplasm caused by Human Papilloma Virus, characterized by the presence of recurrent exophytic proliferative lesions. Without curative treatment, costs related to the diagnosis, prevention, and treatment of HPV-related diseases have a significant economic impact worldwide. However, the lack of national epidemiological data on the incidence and prevalence of laryngeal papillomatosis in Brazil does not allow us to analyze the behavior of the disease in our population, as well as the benefits of vaccination. Objective: To estimate the incidence and prevalence of Laryngeal Papillomatosis in the State of São Paulo. Methods: A population study was conducted aiming to raise all the diagnosed cases of Laryngeal Papillomatosis of the State of São Paulo, considering the main centers of diagnosis of this disease. The main services of residence and specialization in Otorhinolaryngology of the State of São Paulo were mapped and selected, based on the data provided by the Brazilian Association of Otorhinolaryngology and Cervical-Facial Surgery (ABORL-CCF). By completing a questionnaire we obtained the data to estimate the minimum prevalence and incidence for the State in 2017. Results: The questionnaire wa... (Complete abstract click electronic access below) / Mestre
440

Studium výskytu genotypů lidského parvoviru B19 u pacientů FN Motol / Human parvovirus B19 genotype study among the patients of Motol Univeristy Hospital

Dubišová, Mária January 2018 (has links)
Parvovirus B19 is a common human pathogen that typically infects erythroid progenitors and causes hematological problems such as anemia and aplastic crises. The clinical presentation depends mainly on the immunological status of the patient. PVB19 can cause serious clinical disorders in immunocompromised patients after transplantation. More than 1500 samples from 90 patients who passed the HSCT in 2015 were tested for the presence of PVB19 in this work. This work describes the incidence of the virus and two typical periods of onset of infection in patients after the transplantation. Although several sources report the negative effect of PVB19 infection on the survival of allogeneic graft patients, this work did not confirm this assertion. Also, the results of this work suggest that allogenic grafts are not the main source for transmission, but that it is likely to be reactivated after long-term persistent or latent PVB19 infections. PVB19 is divided into 3 genotypes. Genotype 1 is the most widespread, genotype 2 is very rare in Europe for the last 10 years, and genotype 3 occurs mainly in tropical localities. This work as the first describes the distribution of genotypes in the Czech Republic. More than 130 samples from 125 PVB19 positive patients, stored in the Motol University Hospital from 2004...

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