Evaluation Of Statistical Methods Research Articles

Effective Optical Image Assessment of Cellulose Paper Immunostrips for Blood Typing.

Novel high-performance biosensing devices, based on a microporous cellulose matrix, have been of great interest due to their high sensitivity, low cost, and simple operation. Herein, we report on the design and testing of portable paper-based immunostrips (IMS) for in-field blood typing in emergencies requiring blood transfusion. Cellulose fibrils of a paper membrane were functionalized with antibodies via supramolecular interactions. The formation of hydrogen bonds between IgM pentamer and cellulose fibers was corroborated using quantum mechanical calculations with a model cellulose chain and a representative amino acid sequence. In the proposed immunostrips, paper with a pore size of 3 µm dia. was used to enable functionalization of its channels with antibody molecules while blocking the red blood cells (RBC) from channel entering. Under the optimized test conditions, all blood types of AB0 and Rh system could be determined by naked eye examination, requiring only a small blood sample (3.5 µL). The durability of IgM immunostrips against storing has been tested. A new method of statistical evaluation of digitized blood agglutination images, compatible with a clinical five-level system, has been proposed. Critical parameters of the agglutination process have been established to enable future development of automatic blood typing with machine vision and digital data processing.

SLEEP WELL

BackgroundThe standard treatment of obstructive sleep apnea (OSA) is nocturnal positive airway pressure (PAP) therapy, which only has positive effects on symptoms and sequelae with regular and long-term use. Interface problems in existing care lead to incorrect treatment and long waiting times in the diagnostics and therapy, which are aggravated by the pandemic.ObjectiveBased on the existing structures a cross-sectoral care treatment model for the diagnostics and therapy of OSA will be evaluated. The central goals are a timely, needs-oriented care with optimized quality and efficiency. Furthermore, treatment adherence and thus quality of life should be improved as well as the cross-sectoral collaboration. The SLEEP WELL project is funded by the G-BA Innovation Fund (funding reference 01NVF20020).Material and methodsThe evaluation will be carried out based on a prospective, randomized, controlled, multicenter study in North Rhine-Westphalia, Germany, in which 4448 patients with suspected OSA receive guideline-compliant care with telemedicine (telemedicine group) or without telemedicine (control group). The 1:1 randomization takes place after initial suspicion by the primary physician. The two groups are compared in terms of quality of life (primary endpoint), PAP therapy adherence, and medical resource use (secondary outcomes).Results and discussionQuantitative data collation occurs at 5 time points. In an intention to treat analysis the results are analyzed using statistical evaluation methods. Patient and provider satisfaction will be assessed using qualitative methods. The cost-benefit relation is examined on the basis of routine health insurance data. In addition, remuneration concepts for standard care will be developed. Project completion is planned for September 2025.

IMPROVING THE QUALITY CONTROL OF BROILER CHICKEN CARCASSES THROUGH THE USE OF PHARMACOLOGICAL AGENTS FOR THE CORRECTION AND PREVENTION OF PRE-SLAUGHTER STRESS

This article presents an experiment carried out on broilers of Arbor Acres cross in an industrial poultry farm. For the experiment, the authors divided the broiler birds into three groups. Poultry of the control group received basic ration; poultry of the 1st experimental group received feed additive at a dose of 1269 g/t feed 5 days before slaughter; poultry of the 2nd experimental group received feed additive at a dose of 1693 g/t feed 5 days before slaughter. Broilers were slaughtered on day 38 of rearing. The following types of defects were recorded during slaughtering: dermatitis, cellulitis; back scratches; splinter hemorrhages, bruises, hematomas, bruises; dislocations, closed and open fractures; poor bleeding; skin tears; under-plucking; the presence of internal organs; over-steaming of the carcass. The authors applied the Ishikawa method, Pareto charts, ABC analysis, and cluster analysis to assess the quality of broiler chicken carcasses. Based on the results of these studies, the authors identified 41.7 % of defects that reduce the quality of poultry carcasses and 58.3 % of critical defects that lead to meat culling. Using clustering methods and ABC analysis, the authors identified the most important category of critical defect, D2C. This defect in poultry occurs during the rearing and processing phase. The application of the stress-corrector reduced the number of D2C defects in the 1st experimental group by 33.3 %; in the 2nd experimental group by 18.2; D2GD in the 2nd experimental group by 22.2 %. Thus, the use of statistical evaluation methods increases the efficiency of industrial control over the quality level of broiler chicken carcasses.

State-of-charge estimation using data fusion for vanadium redox flow battery

Accurate estimation of the state of charge (SOC) is important for preventing overcharge and overdischarge of vanadium redox flow batteries (VRFBs). In this paper, we propose a data-fusion (DF) method to improve the accuracy of SOC estimation for VRFBs by combining two different SOC estimation results. First, the extended Kalman filter (EKF) and adaptive extended Kalman filter (AEKF) were used to estimate the SOC according to the equivalent circuit model (ECM) of the VRFB. Thereafter, the SOC estimation results of the EKF and AEKF were utilized separately as the basic estimation of the DF method to obtain two different DF results, which can be explicitly divided into DF-EKF and DF-AEKF. The ECM parameters were extracted using the recursive least squares (RLS) algorithm in real time. Subsequently, an experiment involving a hybrid pulse discharge was conducted to validate the proposed method. Here, the root-mean-square error (RMSE) and mean absolute error (MAE) are used as statistical methods for outcome evaluation. Compared with the RMSE and MAE (0.0012, 0.0010, and 0.0010 and 0.0009) of the EKF and AEKF, the RMSE and MAE of the DF-EKF decreased by 33.3%, 20%, and 36.3% and 22.2% to 0.0008 and 0.0007, respectively. The same downward trend also occurs in DF-AEKF. The RMSE of the results of DF-AEKF decreased by 33.3% and 20% to 0.0008, and the MAE decreased by 45.5% and 33.3% to 0.0006, respectively. The results show that the proposed DF method exhibited a high fidelity and accuracy in estimating the SOC of the VRFB.

Разработка рейтинговой системы контроля качества сухих напитков функциональной направленности

Excessive information about a functional product and its qualitative characteristics increases the competitiveness of the product and requires constant monitoring. The present research objective was to develop a rating system of qualitative characteristics for functional instant drinks. The system relied on the method of multidimensional statistical analysis and involved the main descriptors of consumer criteria and sensory properties of the product.
 The study featured functional instant fruit and berry drinks, e.g. raspberry, cranberry, cranberry, black currant, blueberry, sea buckthorn, blackberry, apricot, peach, apple, etc. The methods included a focus group approach, a sensory analysis, a new ordinal scale, and a modified method of multivariate statistical evaluation (PCA).
 The authors introduced a unified score scale for sensory evaluation of functional instant drinks, which reflected both standard quality indicators and consumer selection criteria. A modified method of multivariate statistical evaluation (PCA) was used to identify the characteristics that consumers see as the most important. The resulting rating system of the main descriptors reflects the information about consumer preferences and reveals significant sensory characteristics and indicators of quality of functional instant drinks. Clustering revealed two groups of consumers, young people aged 18–29 and those aged 30–59, with their own defining quality indicators.
 The article contains some useful labeling recommendations for producers of functional instant beverages. The recommendations can increase the competitiveness of the product and meet consumer demand for information. The new scale can be used for various types of functional fruit and berry drinks.

One-Year Mortality Is Not a Reliable Indicator of Lung Transplant Center Performance

BackgroundIn the United States, the Organ Procurement and Transplant Network (OPTN) uses 1-year mortality as the primary measure of transplant center quality. We sought to evaluate the reliability of mortality outcomes in lung transplantation and to compare statistical methods of program performance evaluation. MethodsWe used the Standard Transplant Analysis and Research files from the United Network for Organ Sharing to identify lung transplant recipients from 2013 to 2018 in the United States. We stratified hospitals on the basis of 30-day, 1-year, and 5-year survival by risk adjustment, reliability adjustment with empirical Bayes technique, and hierarchical bayesian mixed effects models currently used by the OPTN. We measured variation in mortality rates and identification of performance outliers between techniques. ResultsWe identified 12,769 recipients in 69 centers. Reliability adjustment reduced variation in hospital outcomes and had a large impact on hospital mortality rankings. For example, with 1-year mortality, 28% (5 hospitals) of the “best” hospitals (top 25%) and 18% (3 hospitals) of the “worst” hospitals (bottom 25%) were reclassified after reliability adjustment. The overall reliability of 1-year mortality was low at 0.42. Compared with the bayesian method used by the OPTN, reliability adjustment identified fewer outliers. The 5-year survival reached a higher reliability plateau with a lower volume of cases required. ConclusionsThe reliability of 1-year mortality in lung transplantation is low, whereas 5-year survival estimates may be more reliable at lower case volumes. Reliability adjustment yielded more conservative measures of center performance and fewer outliers compared with current bayesian methods.

Statistical Assessment of Electric Shock Hazard in MV Electrical Power Substations Supplied from Networks with Non-Effectively Earthed Neutral Point

This paper focuses on the evaluation of the electric shock hazard accompanying earth faults in a non-effectively earthed medium-voltage (MV) electrical power network. This hazard depends on the duration and value of the fault current. While the fault current depends on several factors, the most important is the neutral point earthing method. The value of the fault current affects the earthing-electrode voltage value, being the basis for the assessment of electric shock hazard in MV/LV substations. The earthing-electrode voltage is also influenced by the resistance of the substation earthing, which in practice is random. Therefore, an original statistical evaluation method for assessing the electric shock hazard has been developed and presented in this paper. It is based on a statistical model of the MV/LV substation earthing resistance, worked out on the basis of experiments and measurements in real electrical power networks. This method can be used for the determination of statistical distributions of earthing-conductor voltages in real electrical power networks, and on this basis, the MV/LV substations with rates of electric shock hazard that are too high can be indicated. This also makes it possible to determine the longest permissible fault current interruption times or the highest permissible earthing resistances for specific substations. This method is also applicable when selecting the neutral point earthing method. The developed method was used in all of the above proposed areas by performing calculations on a model of a real 15 kV network with the neutral point earthed by a resistor. This analysis proves the practicability of the method both at the stage of designing power networks, and when a change in the neutral point earthing method in existing networks is being considered. Particularly valuable is also the statistical model of an earthing electrode resistance, developed on the basis of measurements in 2408 MV/LV substations, which may also be applicable in the future studies.

The Social Dimension of Security: The Dichotomy of Respondents’ Perceptions during the COVID-19 Pandemic

The main goal of the study was to make a subjective assessment of the social security of households during the coronavirus pandemic. In order to achieve this goal, a three-stage primary research based on the CAWI method (computer-assisted web interview) was conducted on households in Poland in April, June, and September 2020. The research used statistical methods of structure evaluation and the fuzzy TOPSIS method. It assessed the security of households and respondents’ subjective perceptions of the loss of financial stability, income, and employment, as well as presenting the deterioration of the situation of their households in the immediate future. The respondents also assessed the possible deterioration of the situation in Poland, the growth of poverty in families and unemployment in the immediate future. In addition, the respondents’ subjective assessments of the level of insecurity about the future of their households and the situation in Poland were quantified. One of the most important conclusions was the dichotomy in the respondents’ perceptions, as they assessed the situation of their households better than the situation in Poland. The research shows that in April 2020, i.e., at the first stage of the research, the respondents strongly felt that the financial situation of their households had deteriorated. In June 2020 (stage II) this perception weakened slightly because they may have considered the pandemic situation to be temporary. However, in September 2020 (stage III) the sense of the possible deterioration of their financial situation increased again due to the ongoing pandemic and its consequences.

The discussion of related issues in the efficacy evaluation of COVID-19 vaccine

The COVID-19 swept across the countries and regions all over the world in the past one year. The marketing of an effective and safe COVID-19 vaccine is expected to control the spread of the disease. A placebo-controlled field efficacy trial is generally considered in the pivotal study of COVID-19 vaccine to observe whether it is able to reduce the incidence rate of the disease effectively. This paper is to introduce and discuss the considerations in study design and the choice of endpoint, statistical evaluation methods, primary estimand choosing and the strategies to various intercurrent events in the COVID-19 efficacy trials.

Deriving Forest Stand Information from Small Samples: An Evaluation of Statistical Methods

Deriving Forest Stand Information from Small Samples: An Evaluation of Statistical Methods

Genetic evaluation and selection in Jatropha curcas through Frequentist and Bayesian inferences

An accurate and efficient statistical method for genetic evaluation is a key requirement for progress in any breeding program. Thus, the present study aimed to evaluate the performance of Frequentist and Bayesian inferences for repeated measures analysis in Jatropha curcas breeding. To this end, 730 individuals from 73 half-sib families were evaluated for grain yield trait, over six crop years. Frequentist and Bayesian analyses were made considering repeatability models with different residual variance structures. Variance components were estimated through restricted maximum likelihood (REML) and Markov Chain Monte Carlo (MCMC). Genetic values were predicted through best linear unbiased prediction (BLUP) and estimated through MCMC. Variance components and genetic and non-genetic parameters estimated by the Frequentist inference presented values similar to those estimated by the Bayesian inference. The selective accuracy presented high magnitude (0.84) by the Frequentist and Bayesian inferences, indicating high reliability. Confidence and highest posterior density (HPD) intervals were similar for the genetic parameters, however the HPD intervals range was slightly short. This study highlighted the importance of testing the residual variance structure and pointed out that the Frequentist and Bayesian inferences presented similar results when using non-informative prior. Then, both inferences can be efficiently applied in Jatropha curcas breeding.

Экономическая модель эффективности крестьянских (фермерских) хозяйств в пространственном развитии России

The article presents an analysis of the participation of peasant (farmer) farms in the rural economy, and hence in the spatial development of Russia. The article identifies and groups the main problems reflected in the Spatial Development Strategy of Russia that hinder the positive dynamics of the development of the social sphere, depending on the impact of the efficiency of the farming sector on their solution. Using the methods of economic and statistical evaluation of the dynamics series over 30 years and extrapolation of the trends obtained for individual production indicators, the authors proved that the participation of farm owners in the production of agricultural products will increase in the near future, which will ensure employment and income growth in rural areas. At the same time, the efficiency of farming is not yet adequate to its potential. Based on the analysis, the authors have developed proposals to improve the basic characteristics of the economic model of effective farming: number, concentration, specialization, resource provision, participation in the process of cooperation, profitability. Particular attention is paid to the review of the directions of diversification of farming activities due to its non-agricultural types, the participation of farm owners in solving social problems of rural areas and the development of rural infrastructure.

ЕФЕКТИВНІСТЬ ЗАЛУЧЕННЯ ФІНАНСУВАННЯ НА РИНКУ ДЕРЖАВНОГО БОРГУ УКРАЇНИ ТА ПОЛЬЩІ

The study of the issue of assessing the effectiveness of attracting financing in the public debt market is still relevant. This is due to the constant increase in public debt in all countries without exception: the least developed and the most developed. Today, the large amount of public debt does not mean the presence of problems with the economy. The problems stem from inefficient management of such debts. Methods and tools that can be used to assess the effectiveness of attracting financing in the public debt market are quite broad. However, the more factors are taken into account in such an assessment, the better and more reliable the assessment will be. The effectiveness of attracting financing in the country's public debt market should take into account the conditions that characterize the state of the country's economy. The best option is to take into account the macroeconomic parameters of economic development, such as: the volume of GDP in actual prices, state budget revenues, the size of international reserves, inflation index. After all, it is the macroeconomic situation in the country that determines the opportunities and the need to attract financing in the external and domestic markets of public debt. The effectiveness of attracting financing in the public debt market can be carried out using both qualitative and quantitative instruments. The calculation of the efficiency ratio refers to quantitative statistical evaluation methods. In this case, this ratio can be modified by adding a number of new factors that are defined as either positive or negative factors. The assessment of debt financing is carried out in terms of external and domestic debt of two countries – Ukraine and Poland, which are at different levels of economic development. This allowed to interpret the results of calculations as objectively as possible and to take into account the conditions of debt financing of the needs of the economy of Ukraine and Poland. Expanding the tools for assessing the effectiveness of attracting financing in the public debt market is of practical importance and allows you to use different variations of the indicator by adding factors. This is the basis of further research.

Development of a Statistical Evaluation Method for Core Hot Spot Temperature in Sodium-Cooled Fast Reactor Under Natural Circulation Conditions

Development of a Statistical Evaluation Method for Core Hot Spot Temperature in Sodium-Cooled Fast Reactor Under Natural Circulation Conditions

Evaluation of melt quality during polymer extrusion

Polymer materials are widely spread and used in all industry sectors. The operating properties of polymer products make them practically indispensable in various industries. They have acquired widespread popularity and their production volumes are predicted to grow every year. The extrusion of polymers is one of the main methods for their processing. The melt uniformity is one of the main factors that influence the quality of the products and is determined by the level of mixing, i.e., by the redistribution of additives in a dispersion medium when these additives are introduced into the main polymer. The influence of working conditions, geometry of working bodies and other parameters on the melt temperature uniformity was determined. Nowadays, there are a lot of methods for determining the melt uniformity. They can be used indirectly in or after the extrusion process and can be short or long lasting, which in fact determines the acceptability of each of the methods. To determine the melt uniformity, statistical evaluation methods, which have been verified by many experiments and are well known, are often used. The analysis showed that the mixing index is most sensitive among the criteria described. 
 Although statistical criteria of evaluating the melt uniformity are widespread, it is better to use parameters that allow the state of the mixture to be analyzed directly in the work process for the extrusion of polymers, to identify those that depend on the mixing process. Methods and criteria for verifying the melt quality were analyzed and potential use of their temperature uniformity for measuring and evaluating the melt quality directly in the extrusion process, to eliminate the costly sampling process, was determined.

Using the paleotsunami data for the tsunami hazard assessment

The article is focused on the development of statistical methods of the tsunami recurrence evaluation using paleotsunami data. The new key moment is the creation of a model to quantify the preservation potential of paleotsunami deposits. The article includes a brief overview of the results of studies of the variability and preservation of tsunami deposits. The model was tested on materials about paleotsunami on the coast in the Khalaktyrka area (a village within the city of Petropavlovsk-Kamchatsky), obtained earlier, for four time intervals set by the key-marker volcanic tephra layers in Kamchatka (Ksudach in 1907, Avachinsky in 1855 and 1779, Opala in 606). The maximum likelihood estimates of the number of tsunamigenic horizons for the indicated time intervals are given. The restrictions of the considered model are analyzed.

Laser triangulation as a fast and reliable method for determining ribbon solid fraction; focus on accuracy, precision, and measurement time

Roller compaction and dry granulation represent well-established unit operations in the pharmaceutical industry. The ribbon solid fraction is classified as a critical quality attribute, that directly impacts final product quality and performance. The development and evaluation of novel methods measuring ribbon solid fraction represent a subject of current research, since novel analyses strategies need to be established for at-, on–, or in-line process monitoring to overcome limitations of end product testing and to set the course for continuous manufacturing. In this study, a novel analytical device, using the principle of laser triangulation, was investigated to asses its potential being used as at-line process analytical technology tool during a roller compaction process. To this end, the laser triangulation device was compared with X-ray micro-computed tomography and powder based volume displacement measurement techniques using different statistical evaluation methods. Special focus was given to accuracy, precision, and total measurement time. The laser triangulation device was confirmed as highly accurate and precise, enabling the shortest total measurement time compared to the other methods. The findings of this study support the idea of implementing the laser triangulation device as a novel at-line process analytical technology tool into a roller compaction process.

Monthly Streamflow Forecasting Using Convolutional Neural Network

Monthly streamflow forecasting is vital for managing water resources. Recently, numerous studies have explored and evidenced the potential of artificial intelligence (AI) models in hydrological forecasting. In this study, the feasibility of the convolutional neural network (CNN), a deep learning method, is explored for monthly streamflow forecasting. CNN can automatically extract critical features from numerous inputs with its convolution–pooling mechanism, which is a distinct advantage compared with other AI models. Hydrological and large-scale atmospheric circulation variables, including rainfall, streamflow, and atmospheric circulation factors are used to establish models and forecast streamflow for Huanren Reservoir and Xiangjiaba Hydropower Station, China. The artificial neural network (ANN) and extreme learning machine (ELM) with inputs identified based on cross-correlation and mutual information analyses are established for comparative analyses. The performances of these models are assessed with several statistical metrics and graphical evaluation methods. The results show that CNN outperforms ANN and ELM in all statistical measures. Moreover, CNN shows better stability in forecasting accuracy.

Design of experiments and multivariate analysis approach to study dissolution stability of a modified-release drug product to support lean design strategies

Objective The purpose of this paper is to present the use of Design of Experiments and multivariate analysis for evaluation of a modified-release drug product stability to support post-approval lean stability approaches. The focus of the paper was to investigate potential root-causes for acceleration of dissolution upon stability. Methods For statistical evaluation of stability data, multiple linear regression statistics was used. The design space of the stability study was modeled using MODDE 12.1 software. For experimental set-up, parameters such as Temperature, Time, Packaging, Batch, and Active Pharmaceutical Ingredient supplier were selected. Results With multiple linear regression modeling of the all generated stability data until six months, we were able to identify or confirm the Stability-related quality attributes and Shelf life limiting attributes. From the multiple linear regression correlation coefficients, we have evaluated that decrease of an antioxidant upon stability could cause potential shift in dissolution. However, main factors for accelerated dissolution can be attributed to other material and process variables. In the last part of the study, we have shown the usefulness of these methodologies for supporting lean stability approaches. With enhanced drug product knowledge, we designed two reduced long-term stability studies and showed that with ‘One-half’ reduced design, we would still be able to confirm 24-month shelf life. Conclusions Implementing Quality by design approaches on stability studies could reduce the need for excessive analytical testing, help to evaluate meaningfulness of the data and set a risk-based stability testing strategy.

Shaping of the evidence-based substitution conceptual framework of the original medicines to generic counterparts in Ukraine

The aim. To develop conceptual framework of the strategy for a reasonable transition from original to generic medicines by complex implementation of proper bioequivalence studies and sufficient therapeutic drug monitoring management.
 Materials and methods. To conduct the study, we used the lists of medicines included in the state reimbursement program “Dostupny Liky” (Affordable Medicines), and materials of reports on medicines public procurement provided on the website of the Ministry of Health of Ukraine and the National Health Service of Ukraine, as well as information data on the results of studies of the quality and effectiveness of these drugs provided by the Rx-Index website. In the course of the study, the methods of logical analysis, SWOT analysis, and statistical evaluation of results, Kingdon’s Policy Streams Approach and the method of flowcharts construction were used. The concept of evidence-based medicine substitution formation in Ukraine was designed applying the Policy Streams Approach.
 Results. The analysis of public procurement programs for drugs for the period 2018–2020, as well as the analysis of drugs included in the new list under the “Dostupny Liky” (Affordable Medicines) program, carried out in the course of the study, showed that the level of evidence of data on assessing their effectiveness remains low. At the same time, more than 1.5 billion UAH (~ 50 mln USD) is spent annually on the purchase of such drugs and reimbursement of their cost, and the question of the optimal selection and monitoring of pharmacotherapy with these drugs remains open. A structural model has been developed, in which three basic levels are identified: provision of regulatory and financial components, executive and the level of implementation of the results. The SWOT-analysis of the strengths and weaknesses, as well as external opportunities and threats for the implementation of the conceptual framework made it possible to substantiate the advantages and reveal the possibilities of attracting clinical centers of universities and research institutions to the implementation of the concept. A framework for the interaction of a research center with health care institutions in the implementation of therapeutic drug monitoring was developed for low-income and low-middle income countries on the example of Ukraine. Distribution of responsibilities was proposed and the basic principles of interaction between performers of therapeutic drug monitoring were highlighted.
 Conclusions. Based on the results of the analysis of the evidence of the quality and effectiveness of drugs included in public procurement and in reimbursement programs, the key problems of organizing pharmaceutical provision of an appropriate level of quality for a number of chronic diseases requiring lifelong therapy were identified. The conceptual framework of evidence-based original medicines substitution to generic counterparts have been formed; and the ways of its implementation in the conditions of scarce financial resources on the example of Ukraine have been substantiated