Method comparison studies consist of a unique study design aiming to examine agreement between two methods to measure a physiological or clinical parameter evaluated using continuous variables. Such physiological parameters are used by healthcare providers along with other clinical data to inform diagnoses and treatment decisions. When novel methods are proposed to measure a continuous physiological parameter, method comparison studies are needed to examine the agreement between this new method and an existing method that is used in standard clinical care. This standard method is generally considered as the gold standard measurement for a given physiological parameter. The issue of repeated measurements poses special challenges when conducting method comparison studies. Repeated measurements occur when a given individual included in a method comparison study has multiple measurements, which are inherently correlated with one another and are not independent (e.g., multiple glucose measurements carried out for the same patient throughout the day using a blood test, compared to a portable point-of-care device). The limits of agreement (LOA) method proposed by Bland & Altman has been adapted to adjust for the correlation between repeated measurements and is widely used for the analysis of method comparison studies that include repeated measurements. However, other statistical methods have been proposed as alternatives to LOA analysis to inform the analysis of method comparison studies with repeated measurements. There is a gap in the literature to inform this type of analysis, whereby no guidelines or synthesis of statistical methods that can be used as alternatives to the LOA method with repeated measurements have been published. Therefore, this thesis aimed to systematically review the existing literature to identify existing alternate statistical methods for the analysis of method comparison studies that include repeated measurements, using a scoping review framework. The findings of this scoping review were used to inform the analysis of the PREMISE (Point-of-care hemoglobin accuracy and transfusion outcomes in non-cardiac surgery) study, a large prospective observational method comparison study that included repeated measurements. The aim of the PREMISE study was to examine the agreement between frequently used point-of-care devices to measure hemoglobin (POCT-Hgb) and laboratory-measured hemoglobin (lab-Hgb) in the operative setting. To further increase the understanding of the challenges associated with the analysis of method comparison studies that include repeated measurements, the analyses pertaining to agreement were performed in the context of this thesis. The findings of the PREMISE study fill an important gap in the literature pertaining to transfusion decision-making in the operative setting, where there is a paucity of evidence on the accuracy of POCT-Hgb devices, as well as from trials and transfusion guideline.

<p>In order to examine the usefulness of the multi breath helium dilution method (MB) it was compared to the single breath helium dilution method (SB) and body plethysmography (BP). Residual volume (RV), total lung capacity (TLC) and vital capacity (VC) were measured in seventeen subjects with obstructive (11) or restrictive (6) lung disease and four normal subjects.</p><p>With information from professional literature and current periodicals, advantages and disadvantages with all three methods were compared. ANOVA and Student's t-test were performed on the measurement results.</p><p>The results of the statistical tests tell us there are differences among the methods in the group of obstructive patients. They also reveal a notable difference between the MB and SB methods when measuring the same parameter. In addition, it was noted that none of the existing sets of prediction equations fulfill the requirements established on high quality lung function testing.</p><p>Although a thorough evaluation of the reproducibility of the method is still required, it appears to be a viable alternative to body plethysmography. We claim that measuring the above mentioned static lung volumes with only the single breath helium dilution method cannot be considered a satisfactory practice.</p>

Nowadays, Machine learning (ML) has been utilized in various kinds of area which across the range from engineering field to business area. In this paper, we first present several kernel machine learning methods of solving classification, regression and clustering problems. These have good performance but also have some limitations. We present examples to each method and analyze the advantages and disadvantages for solving different scenarios. Then we focus on one of the most popular classification methods, Support Vectors Machine (SVM). In addition, we introduce the basic theory, advantages and scenarios of using Support Vector Machine (SVM) deal with classification problems. We also explain a convenient approach of tacking SVM problems which are called Sequential Minimal Optimization (SMO). Moreover, one class SVM can be understood in a different way which is called Support Vector Data Description (SVDD). This is a famous non-linear model problem compared with SVM problems, SVDD can be solved by utilizing Gaussian RBF kernel function combined with SMO. At last, we compared the difference and performance of SVM-SMO implementation and SVM-SVDD implementation. About the application part, we utilized SVM method to handle seizure forecasting in canine epilepsy, after comparing the results from different methods such as random forest, extremely randomized tree, and SVM to classify preictal (pre-seizure) and interictal (interval-seizure) binary data. We draw the conclusion that SVM has the best performance.

Alcohol expectancies have been shown to be predictive of risk for alcohol problems. Experimental research studies have challenged participants' expectancies with the end result demonstrating a mediational effect on participant drinking. Cognitive research using priming and word recognition tasks have led to the theory that expectancies operate in an associative network. Using dissimilarities information this network has been mapped using multidimensional scaling. The current techniques for collecting dissimilarities information directly in alcohol expectancy research has been limited to the use of the paired comparisons tasks. In order to investigate the utility of a different similarities task a comparison was made between a card sorting task and paired comparisons. The overall comparisons of matrices and Individual Difference Scaling (INDSCAL; Carroll & Chang, 1970) results followed the expected trends and generally supported the hypotheses that the two methods would provide essentially the same information. However, a possible method effect for gender was observed. The method effect was seen when comparing across methods within the females dichotomized by drinker category. Further studies are necessary to replicate these findings and to attempt to identify which method has the effect.

In this work, a practical approach to assessing bias and uncertainty using patient samples in a clinical laboratory is presented. The scheme is essentially a splitsample setup where one instrument is appointed to being the “master” instrument which other instruments are compared to. The software presented automatically collects test results from a Laboratory Information System in production and couples together the results of pairwise measurements. Partitioning of measurement results by user-defined criteria and how this can facilitate isolation of variation sources are also discussed. The logic and essential data model are described and the surrounding workflows outlined. The described software and workflow are currently in considerable practical use in several Swedish large-scale distributed laboratory organizations. With the appropriate IT-support, split-sample testing can be a powerful complement to external quality assurance.

Title from PDF of title page. / Document formatted into pages; contains 64 pages. / Thesis (M.A.)--University of South Florida, 2003. / Includes bibliographical references. / Text (Electronic thesis) in PDF format. / ABSTRACT: Alcohol expectancies have been shown to be predictive of risk for alcohol problems. Experimental research studies have challenged participants' expectancies with the end result demonstrating a mediational effect on participant drinking. Cognitive research using priming and word recognition tasks have led to the theory that expectancies operate in an associative network. Using dissimilarities information this network has been mapped using multidimensional scaling. The current techniques for collecting dissimilarities information directly in alcohol expectancy research has been limited to the use of the paired comparisons tasks. In order to investigate the utility of a different similarities task a comparison was made between a card sorting task and paired comparisons. / ABSTRACT: The overall comparisons of matrices and Individual Difference Scaling (INDSCAL; Carroll & Chang, 1970) results followed the expected trends and generally supported the hypotheses that the two methods would provide essentially the same information. However, a possible method effect for gender was observed. The method effect was seen when comparing across methods within the females dichotomized by drinker category. Further studies are necessary to replicate these findings and to attempt to identify which method has the effect. / System requirements: World Wide Web browser and PDF reader. / Mode of access: World Wide Web.

In order to examine the usefulness of the multi breath helium dilution method (MB) it was compared to the single breath helium dilution method (SB) and body plethysmography (BP). Residual volume (RV), total lung capacity (TLC) and vital capacity (VC) were measured in seventeen subjects with obstructive (11) or restrictive (6) lung disease and four normal subjects. With information from professional literature and current periodicals, advantages and disadvantages with all three methods were compared. ANOVA and Student's t-test were performed on the measurement results. The results of the statistical tests tell us there are differences among the methods in the group of obstructive patients. They also reveal a notable difference between the MB and SB methods when measuring the same parameter. In addition, it was noted that none of the existing sets of prediction equations fulfill the requirements established on high quality lung function testing. Although a thorough evaluation of the reproducibility of the method is still required, it appears to be a viable alternative to body plethysmography. We claim that measuring the above mentioned static lung volumes with only the single breath helium dilution method cannot be considered a satisfactory practice.

Blood transfusion is a very common procedure. Before a blood transfusion it is important to find compatible blood for the patient. If the blood is incompatible with that of the patient a transfusion reaction may occur, which can be mortal. It is also important to avoid alloimmunisation. Alloimmunisation occurs when antibodies are produced against a specific antigen. These antibodies are called irregular antibodies and they can be produced after a transfusion, pregnancy, or transplantation. Alloimmunisation makes it harder to find compatible blood for patients in the future and it is a major concern for patients who require blood transfusions repeatedly. By phenotyping erythrocyte antigens, it is easier to find compatible blood for patients before a blood transfusion. Until now, a manual method has been used for phenotyping erythrocyte antigen at the Sundsvall County hospital and an automatization of this method was desired. For this study, 99 anonymised blood doner tests were used. The erythrocyte antigens M, Jka, Jkb, Fya, Fyb, S and s were phenotyped both manually and automated with ORTHO Vision Analyzer. A Clopper Pearson test was used to evaluate the accordance between the methods. A comparison was also made in regard totime and cost. The results showed a good accordance between the methods. The automated procedure using ORTHO Vision has several advantages over the manual procedure using gel cards. The risk of errors is reduced, there are fewer manual steps, it is faster and the personnel can do other tasks while the instrument is processing the tests.

Understanding 3D genome structure is crucial to learn how chromatin folds and how genes are regulated through the spatial organization of regulatory elements. Various technologies have been developed to investigate genome architecture. These technologies include ligation-based 3C Methodologies such as Hi-C and Micro-C, ligation-based pull-down methods like Proximity Ligation-Assisted ChIP-seq (PLAC Seq) and Paired-end tag sequencing (ChIA PET), and ligation-free methods like Split-Pool Recognition of Interactions by Tag Extension (SPRITE) and Genome Architecture Mapping (GAM). Although these technologies have provided great insight into chromatin organization, a systematic evaluation of these technologies is lacking. Among these technologies, Hi-C has been one of the most widely used methods to map genome-wide chromatin interactions for over a decade. To understand how the choice of experimental parameters determines the ability to detect and quantify the features of chromosome folding, we have first systematically evaluated two critical parameters in the Hi-C protocol: cross-linking and digestion of chromatin. We found that different protocols capture distinct 3D genome features with different efficiencies depending on the cell type (Chapter 2). Use of the updated Hi-C protocol with new parameters, which we call Hi-C 3.0, was subsequently evaluated and found to provide the best loop detection compared to all previous Hi-C protocols as well as better compartment quantification compared to Micro-C (Chapter 3). Finally, to understand how the aforementioned technologies (Hi-C, Micro-C, PLAC-Seq, ChIA-PET, SPRITE, GAM) that measure 3D organization could provide a comprehensive understanding of the genome structure, we have performed a comparison of these technologies. We found that each of these methods captures different aspects of the chromatin folding (Chapter 4). Collectively, these studies suggest that improving the 3D methodologies and integrative analyses of these methods will reveal unprecedented details of the genome structure and function.

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