Design and statistical problems in prevention.
Gullberg, B
1996-01-01
Clinical and epidemiological research in osteoporosis can benefit from using the methods and techniques established in the area of chronic disease epidemiology. However, attention has to be given to the special characteristics such as the multifactorial nature and the fact that the subjects usually are of high ages. In order to evaluate prevention it is of course first necessary to detect and confirm reversible risk factors. The advantage and disadvantage of different design (cross-sectional, cohort and case-control) are well known. The effects of avoidable biases, e.g. selection, observation and confounding have to be balanced against practical conveniences like time, expenses, recruitment etc. The translation of relative risks into population attributable risks (etiologic fractions, prevented fractions) are complex and are usually performed under unrealistic, simplified assumptions. The consequences of interactions (synergy) between risk factors are often neglected. The multifactorial structure requires application of more advanced multi-level statistical techniques. The common strategy in prevention to target a cluster of risk factors in order to avoid the multifactorial nature implies that in the end it is impossible to separate each unique factor. Experimental designs for evaluating prevention like clinical trials and intervention have to take into account the distinction between explanatory and pragmatic studies. An explanatory approach is similar to an idealized laboratory trial while the pragmatic design is more realistic, practical and has a general public health perspective. The statistical techniques to be used in osteoporosis research are implemented in easy available computer-packages like SAS, SPSS, BMDP and GLIM. In addition to the traditional logistic regression methods like Cox analysis and Poisson regression also analysis of repeated measurement and cluster analysis are relevant.
Multifactorial modelling of high-temperature treatment of timber in the saturated water steam medium
NASA Astrophysics Data System (ADS)
Prosvirnikov, D. B.; Safin, R. G.; Ziatdinova, D. F.; Timerbaev, N. F.; Lashkov, V. A.
2016-04-01
The paper analyses experimental data obtained in studies of high-temperature treatment of softwood and hardwood in an environment of saturated water steam. Data were processed in the Curve Expert software for the purpose of statistical modelling of processes and phenomena occurring during this process. The multifactorial modelling resulted in the empirical dependences, allowing determining the main parameters of this type of hydrothermal treatment with high accuracy.
Artificial neural networks in gynaecological diseases: current and potential future applications.
Siristatidis, Charalampos S; Chrelias, Charalampos; Pouliakis, Abraham; Katsimanis, Evangelos; Kassanos, Dimitrios
2010-10-01
Current (and probably future) practice of medicine is mostly associated with prediction and accurate diagnosis. Especially in clinical practice, there is an increasing interest in constructing and using valid models of diagnosis and prediction. Artificial neural networks (ANNs) are mathematical systems being used as a prospective tool for reliable, flexible and quick assessment. They demonstrate high power in evaluating multifactorial data, assimilating information from multiple sources and detecting subtle and complex patterns. Their capability and difference from other statistical techniques lies in performing nonlinear statistical modelling. They represent a new alternative to logistic regression, which is the most commonly used method for developing predictive models for outcomes resulting from partitioning in medicine. In combination with the other non-algorithmic artificial intelligence techniques, they provide useful software engineering tools for the development of systems in quantitative medicine. Our paper first presents a brief introduction to ANNs, then, using what we consider the best available evidence through paradigms, we evaluate the ability of these networks to serve as first-line detection and prediction techniques in some of the most crucial fields in gynaecology. Finally, through the analysis of their current application, we explore their dynamics for future use.
Genetics and child psychiatry: I Advances in quantitative and molecular genetics.
Rutter, M; Silberg, J; O'Connor, T; Simonoff, E
1999-01-01
Advances in quantitative psychiatric genetics as a whole are reviewed with respect to conceptual and methodological issues in relation to statistical model fitting, new genetic designs, twin and adoptee studies, definition of the phenotype, pervasiveness of genetic influences, pervasiveness of environmental influences, shared and nonshared environmental effects, and nature-nurture interplay. Advances in molecular genetics are discussed in relation to the shifts in research strategies to investigate multifactorial disorders (affected relative linkage designs, association strategies, and quantitative trait loci studies); new techniques and identified genetic mechanisms (expansion of trinucleotide repeats, genomic imprinting, mitochondrial DNA, fluorescent in-situ hybridisation, behavioural phenotypes, and animal models); and the successful localisation of genes.
Image and multifactorial statistical analyses were used to evaluate the intensity of fluorescence signal from cells of three strains of A. pullulans and one strain of Rhodosporidium toruloides, as an outgroup, hybridized with either a universal o...
How Stuttering Develops: The Multifactorial Dynamic Pathways Theory
Weber, Christine
2017-01-01
Purpose We advanced a multifactorial, dynamic account of the complex, nonlinear interactions of motor, linguistic, and emotional factors contributing to the development of stuttering. Our purpose here is to update our account as the multifactorial dynamic pathways theory. Method We review evidence related to how stuttering develops, including genetic/epigenetic factors; motor, linguistic, and emotional features; and advances in neuroimaging studies. We update evidence for our earlier claim: Although stuttering ultimately reflects impairment in speech sensorimotor processes, its course over the life span is strongly conditioned by linguistic and emotional factors. Results Our current account places primary emphasis on the dynamic developmental context in which stuttering emerges and follows its course during the preschool years. Rapid changes in many neurobehavioral systems are ongoing, and critical interactions among these systems likely play a major role in determining persistence of or recovery from stuttering. Conclusion Stuttering, or childhood onset fluency disorder (Diagnostic and Statistical Manual of Mental Disorders, 5th edition; American Psychiatric Association [APA], 2013), is a neurodevelopmental disorder that begins when neural networks supporting speech, language, and emotional functions are rapidly developing. The multifactorial dynamic pathways theory motivates experimental and clinical work to determine the specific factors that contribute to each child's pathway to the diagnosis of stuttering and those most likely to promote recovery. PMID:28837728
How Stuttering Develops: The Multifactorial Dynamic Pathways Theory.
Smith, Anne; Weber, Christine
2017-09-18
We advanced a multifactorial, dynamic account of the complex, nonlinear interactions of motor, linguistic, and emotional factors contributing to the development of stuttering. Our purpose here is to update our account as the multifactorial dynamic pathways theory. We review evidence related to how stuttering develops, including genetic/epigenetic factors; motor, linguistic, and emotional features; and advances in neuroimaging studies. We update evidence for our earlier claim: Although stuttering ultimately reflects impairment in speech sensorimotor processes, its course over the life span is strongly conditioned by linguistic and emotional factors. Our current account places primary emphasis on the dynamic developmental context in which stuttering emerges and follows its course during the preschool years. Rapid changes in many neurobehavioral systems are ongoing, and critical interactions among these systems likely play a major role in determining persistence of or recovery from stuttering. Stuttering, or childhood onset fluency disorder (Diagnostic and Statistical Manual of Mental Disorders, 5th edition; American Psychiatric Association [APA], 2013), is a neurodevelopmental disorder that begins when neural networks supporting speech, language, and emotional functions are rapidly developing. The multifactorial dynamic pathways theory motivates experimental and clinical work to determine the specific factors that contribute to each child's pathway to the diagnosis of stuttering and those most likely to promote recovery.
Ritchie, Marylyn D.; Hahn, Lance W.; Roodi, Nady; Bailey, L. Renee; Dupont, William D.; Parl, Fritz F.; Moore, Jason H.
2001-01-01
One of the greatest challenges facing human geneticists is the identification and characterization of susceptibility genes for common complex multifactorial human diseases. This challenge is partly due to the limitations of parametric-statistical methods for detection of gene effects that are dependent solely or partially on interactions with other genes and with environmental exposures. We introduce multifactor-dimensionality reduction (MDR) as a method for reducing the dimensionality of multilocus information, to improve the identification of polymorphism combinations associated with disease risk. The MDR method is nonparametric (i.e., no hypothesis about the value of a statistical parameter is made), is model-free (i.e., it assumes no particular inheritance model), and is directly applicable to case-control and discordant-sib-pair studies. Using simulated case-control data, we demonstrate that MDR has reasonable power to identify interactions among two or more loci in relatively small samples. When it was applied to a sporadic breast cancer case-control data set, in the absence of any statistically significant independent main effects, MDR identified a statistically significant high-order interaction among four polymorphisms from three different estrogen-metabolism genes. To our knowledge, this is the first report of a four-locus interaction associated with a common complex multifactorial disease. PMID:11404819
A Dimensionally Reduced Clustering Methodology for Heterogeneous Occupational Medicine Data Mining.
Saâdaoui, Foued; Bertrand, Pierre R; Boudet, Gil; Rouffiac, Karine; Dutheil, Frédéric; Chamoux, Alain
2015-10-01
Clustering is a set of techniques of the statistical learning aimed at finding structures of heterogeneous partitions grouping homogenous data called clusters. There are several fields in which clustering was successfully applied, such as medicine, biology, finance, economics, etc. In this paper, we introduce the notion of clustering in multifactorial data analysis problems. A case study is conducted for an occupational medicine problem with the purpose of analyzing patterns in a population of 813 individuals. To reduce the data set dimensionality, we base our approach on the Principal Component Analysis (PCA), which is the statistical tool most commonly used in factorial analysis. However, the problems in nature, especially in medicine, are often based on heterogeneous-type qualitative-quantitative measurements, whereas PCA only processes quantitative ones. Besides, qualitative data are originally unobservable quantitative responses that are usually binary-coded. Hence, we propose a new set of strategies allowing to simultaneously handle quantitative and qualitative data. The principle of this approach is to perform a projection of the qualitative variables on the subspaces spanned by quantitative ones. Subsequently, an optimal model is allocated to the resulting PCA-regressed subspaces.
Regression: The Apple Does Not Fall Far From the Tree.
Vetter, Thomas R; Schober, Patrick
2018-05-15
Researchers and clinicians are frequently interested in either: (1) assessing whether there is a relationship or association between 2 or more variables and quantifying this association; or (2) determining whether 1 or more variables can predict another variable. The strength of such an association is mainly described by the correlation. However, regression analysis and regression models can be used not only to identify whether there is a significant relationship or association between variables but also to generate estimations of such a predictive relationship between variables. This basic statistical tutorial discusses the fundamental concepts and techniques related to the most common types of regression analysis and modeling, including simple linear regression, multiple regression, logistic regression, ordinal regression, and Poisson regression, as well as the common yet often underrecognized phenomenon of regression toward the mean. The various types of regression analysis are powerful statistical techniques, which when appropriately applied, can allow for the valid interpretation of complex, multifactorial data. Regression analysis and models can assess whether there is a relationship or association between 2 or more observed variables and estimate the strength of this association, as well as determine whether 1 or more variables can predict another variable. Regression is thus being applied more commonly in anesthesia, perioperative, critical care, and pain research. However, it is crucial to note that regression can identify plausible risk factors; it does not prove causation (a definitive cause and effect relationship). The results of a regression analysis instead identify independent (predictor) variable(s) associated with the dependent (outcome) variable. As with other statistical methods, applying regression requires that certain assumptions be met, which can be tested with specific diagnostics.
Complex biomarker discovery in neuroimaging data: Finding a needle in a haystack☆
Atluri, Gowtham; Padmanabhan, Kanchana; Fang, Gang; Steinbach, Michael; Petrella, Jeffrey R.; Lim, Kelvin; MacDonald, Angus; Samatova, Nagiza F.; Doraiswamy, P. Murali; Kumar, Vipin
2013-01-01
Neuropsychiatric disorders such as schizophrenia, bipolar disorder and Alzheimer's disease are major public health problems. However, despite decades of research, we currently have no validated prognostic or diagnostic tests that can be applied at an individual patient level. Many neuropsychiatric diseases are due to a combination of alterations that occur in a human brain rather than the result of localized lesions. While there is hope that newer imaging technologies such as functional and anatomic connectivity MRI or molecular imaging may offer breakthroughs, the single biomarkers that are discovered using these datasets are limited by their inability to capture the heterogeneity and complexity of most multifactorial brain disorders. Recently, complex biomarkers have been explored to address this limitation using neuroimaging data. In this manuscript we consider the nature of complex biomarkers being investigated in the recent literature and present techniques to find such biomarkers that have been developed in related areas of data mining, statistics, machine learning and bioinformatics. PMID:24179856
Theories of Memory and Aging: A Look at the Past and a Glimpse of the Future
Festini, Sara B.
2017-01-01
The present article reviews theories of memory and aging over the past 50 years. Particularly notable is a progression from early single-mechanism perspectives to complex multifactorial models proposed to account for commonly observed age deficits in memory function. The seminal mechanistic theories of processing speed, limited resources, and inhibitory deficits are discussed and viewed as especially important theories for understanding age-related memory decline. Additionally, advances in multivariate techniques including structural equation modeling provided new tools that led to the development of more complex multifactorial theories than existed earlier. The important role of neuroimaging is considered, along with the current prevalence of intervention studies. We close with predictions about new directions that future research on memory and aging will take. PMID:27257229
Ghezzi, Pietro; Davies, Kevin; Delaney, Aidan; Floridi, Luciano
2018-03-06
Biomarkers are widely used not only as prognostic or diagnostic indicators, or as surrogate markers of disease in clinical trials, but also to formulate theories of pathogenesis. We identify two problems in the use of biomarkers in mechanistic studies. The first problem arises in the case of multifactorial diseases, where different combinations of multiple causes result in patient heterogeneity. The second problem arises when a pathogenic mediator is difficult to measure. This is the case of the oxidative stress (OS) theory of disease, where the causal components are reactive oxygen species (ROS) that have very short half-lives. In this case, it is usual to measure the traces left by the reaction of ROS with biological molecules, rather than the ROS themselves. Borrowing from the philosophical theories of signs, we look at the different facets of biomarkers and discuss their different value and meaning in multifactorial diseases and system medicine to inform their use in patient stratification in personalized medicine.
Sarkar, Taposh; Singh, Narinder Pal; Kar, Premashish; Husain, Syed Akhtar; Kapoor, Seema; Pollipalli, Sunil Kumar; Kumar, Anish; Garg, Neena
2016-06-01
Hypertension is one of the important contributing factors linked with both causation and development of kidney disease. It is a multifactorial, polygenic, and complex disorder due to interaction of several risk genes with environmental factors. The present study was aimed to explore genetic polymorphism in ACE-1 gene as a risk factor for CKD among hypertensive patients. Three hundred patients were enrolled in the study. Ninety were hypertensive patients with CKD taken as cases, whereas 210 hypertensive patients without CKD were taken as controls. Demographic data including age, sex, Body mass index (BMI), and other risk factors were also recorded. DNA was extracted from blood by salting out method. Genotyping of ACE gene was done by PCR technique. All the statistical analysis was done by using Epi Info and SPSS version 16 software (SPSS Inc., Chicago, IL). Mean age was higher in the control group (p < 0.05). Variables among two groups were compared out of which age, BMI, hemoglobin (Hb) was found to be statistically significant whereas other variables like systolic blood pressure, triglyceride and low-density lipoprotein were not. Blood urea and serum creatinine levels were statistically significant in the two genotypes (p < 0.05). Total and HDL cholesterol were statistically significant for DD genotype of ACE gene (OR = 1.42, 95% CI = 0.72-2.81). Similarly, the risk for CKD among hypertensive patients was also associated with D allele of ACE gene (OR = 1.25, 95% CI = 0.86-1.79). It is concluded that ACE-DD genotype may be a risk factor for the causation and development of chronic kidney failure among hypertensive patients.
Berthiaume, John T; Davis, Jim; Taira, Deborah A; Thein, Ko Ko
2007-03-01
To evaluate the effect of a managed care organization's multifactorial intervention program in optimizing secondary prevention of coronary artery disease (CAD). Retrospective observational analysis of claims-based data of health plan members with CAD receiving 1 or more prescriptions per year of any of the following classes of medications used for secondary prevention of CAD: lipid-lowering agents, angiotensin-converting enzyme (ACE) inhibitors, or angiotensin receptor blockers (ARBs) and beta-blockers. Claims-based data of members from 2000 to 2004 were analyzed to discover trends in the use of medications for secondary prevention of CAD. chi(2) Test of proportion was used to determine whether the changes in the annual medication use rates were statistically significant. The annual medication use rates improved consistently throughout each year of the study period. From 2000 to 2004, the medication use rates increased for lipid-lowering agents (from 55% to 71%), ACE inhibitors or ARBs (from 44% to 55%), and beta-blockers (from 36% to 47%). Changes in all 3 indicators were statistically significant at P < .001. An integrated multifactorial approach is essential in addressing the underutilization of therapies available for secondary prevention of CAD. Managed care organizations are in a unique position to optimize the use of evidence-based pharmacological and behavioral therapies to effectively prevent and treat the underlying pathophysiology of CAD in member populations.
Ansell, Emily B; Pinto, Anthony; Edelen, Maria Orlando; Grilo, Carlos M
2013-01-01
Objective To examine 1-, 2-, and 3-factor model structures through confirmatory analytic procedures for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) obsessive–compulsive personality disorder (OCPD) criteria in patients with binge eating disorder (BED). Method Participants were consecutive outpatients (n = 263) with binge eating disorder and were assessed with semi-structured interviews. The 8 OCPD criteria were submitted to confirmatory factor analyses in Mplus Version 4.2 (Los Angeles, CA) in which previously identified factor models of OCPD were compared for fit, theoretical relevance, and parsimony. Nested models were compared for significant improvements in model fit. Results Evaluation of indices of fit in combination with theoretical considerations suggest a multifactorial model is a significant improvement in fit over the current DSM-IV single-factor model of OCPD. Though the data support both 2- and 3-factor models, the 3-factor model is hindered by an underspecified third factor. Conclusion A multifactorial model of OCPD incorporating the factors perfectionism and rigidity represents the best compromise of fit and theory in modelling the structure of OCPD in patients with BED. A third factor representing miserliness may be relevant in BED populations but needs further development. The perfectionism and rigidity factors may represent distinct intrapersonal and interpersonal attempts at control and may have implications for the assessment of OCPD. PMID:19087485
Ansell, Emily B; Pinto, Anthony; Edelen, Maria Orlando; Grilo, Carlos M
2008-12-01
To examine 1-, 2-, and 3-factor model structures through confirmatory analytic procedures for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) obsessive-compulsive personality disorder (OCPD) criteria in patients with binge eating disorder (BED). Participants were consecutive outpatients (n = 263) with binge eating disorder and were assessed with semi-structured interviews. The 8 OCPD criteria were submitted to confirmatory factor analyses in Mplus Version 4.2 (Los Angeles, CA) in which previously identified factor models of OCPD were compared for fit, theoretical relevance, and parsimony. Nested models were compared for significant improvements in model fit. Evaluation of indices of fit in combination with theoretical considerations suggest a multifactorial model is a significant improvement in fit over the current DSM-IV single- factor model of OCPD. Though the data support both 2- and 3-factor models, the 3-factor model is hindered by an underspecified third factor. A multifactorial model of OCPD incorporating the factors perfectionism and rigidity represents the best compromise of fit and theory in modelling the structure of OCPD in patients with BED. A third factor representing miserliness may be relevant in BED populations but needs further development. The perfectionism and rigidity factors may represent distinct intrapersonal and interpersonal attempts at control and may have implications for the assessment of OCPD.
Lovelock, Paul K; Spurdle, Amanda B; Mok, Myth T S; Farrugia, Daniel J; Lakhani, Sunil R; Healey, Sue; Arnold, Stephen; Buchanan, Daniel; Couch, Fergus J; Henderson, Beric R; Goldgar, David E; Tavtigian, Sean V; Chenevix-Trench, Georgia; Brown, Melissa A
2007-01-01
Many of the DNA sequence variants identified in the breast cancer susceptibility gene BRCA1 remain unclassified in terms of their potential pathogenicity. Both multifactorial likelihood analysis and functional approaches have been proposed as a means to elucidate likely clinical significance of such variants, but analysis of the comparative value of these methods for classifying all sequence variants has been limited. We have compared the results from multifactorial likelihood analysis with those from several functional analyses for the four BRCA1 sequence variants A1708E, G1738R, R1699Q, and A1708V. Our results show that multifactorial likelihood analysis, which incorporates sequence conservation, co-inheritance, segregation, and tumour immunohistochemical analysis, may improve classification of variants. For A1708E, previously shown to be functionally compromised, analysis of oestrogen receptor, cytokeratin 5/6, and cytokeratin 14 tumour expression data significantly strengthened the prediction of pathogenicity, giving a posterior probability of pathogenicity of 99%. For G1738R, shown to be functionally defective in this study, immunohistochemistry analysis confirmed previous findings of inconsistent 'BRCA1-like' phenotypes for the two tumours studied, and the posterior probability for this variant was 96%. The posterior probabilities of R1699Q and A1708V were 54% and 69%, respectively, only moderately suggestive of increased risk. Interestingly, results from functional analyses suggest that both of these variants have only partial functional activity. R1699Q was defective in foci formation in response to DNA damage and displayed intermediate transcriptional transactivation activity but showed no evidence for centrosome amplification. In contrast, A1708V displayed an intermediate transcriptional transactivation activity and a normal foci formation response in response to DNA damage but induced centrosome amplification. These data highlight the need for a range of functional studies to be performed in order to identify variants with partially compromised function. The results also raise the possibility that A1708V and R1699Q may be associated with a low or moderate risk of cancer. While data pooling strategies may provide more information for multifactorial analysis to improve the interpretation of the clinical significance of these variants, it is likely that the development of current multifactorial likelihood approaches and the consideration of alternative statistical approaches will be needed to determine whether these individually rare variants do confer a low or moderate risk of breast cancer.
Machine learning methods applied on dental fear and behavior management problems in children.
Klingberg, G; Sillén, R; Norén, J G
1999-08-01
The etiologies of dental fear and dental behavior management problems in children were investigated in a database of information on 2,257 Swedish children 4-6 and 9-11 years old. The analyses were performed using computerized inductive techniques within the field of artificial intelligence. The database held information regarding dental fear levels and behavior management problems, which were defined as outcomes, i.e. dependent variables. The attributes, i.e. independent variables, included data on dental health and dental treatments, information about parental dental fear, general anxiety, socioeconomic variables, etc. The data contained both numerical and discrete variables. The analyses were performed using an inductive analysis program (XpertRule Analyser, Attar Software Ltd, Lancashire, UK) that presents the results in a hierarchic diagram called a knowledge tree. The importance of the different attributes is represented by their position in this diagram. The results show that inductive methods are well suited for analyzing multifactorial and complex relationships in large data sets, and are thus a useful complement to multivariate statistical techniques. The knowledge trees for the two outcomes, dental fear and behavior management problems, were very different from each other, suggesting that the two phenomena are not equivalent. Dental fear was found to be more related to non-dental variables, whereas dental behavior management problems seemed connected to dental variables.
Feldman, Jonathan M.; Serebrisky, Denise; Spray, Amanda
2012-01-01
Background Causes of children’s asthma health disparities are complex. Parents’ asthma illness representations may play a role. Purpose The study aims to test a theoretically based, multi-factorial model for ethnic disparities in children’s acute asthma visits through parental illness representations. Methods Structural equation modeling investigated the association of parental asthma illness representations, sociodemographic characteristics, health care provider factors, and social–environmental context with children’s acute asthma visits among 309 White, Puerto Rican, and African American families was conducted. Results Forty-five percent of the variance in illness representations and 30% of the variance in acute visits were accounted for. Statistically significant differences in illness representations were observed by ethnic group. Approximately 30% of the variance in illness representations was explained for whites, 23% for African Americans, and 26% for Puerto Ricans. The model accounted for >30% of the variance in acute visits for African Americans and Puerto Ricans but only 19% for the whites. Conclusion The model provides preliminary support that ethnic heterogeneity in asthma illness representations affects children’s health outcomes. PMID:22160799
Møller, Jens K S; Jakobsen, Marianne; Weber, Claus J; Martinussen, Torben; Skibsted, Leif H; Bertelsen, Grete
2003-02-01
A multifactorial design, including (1) percent residual oxygen, (2) oxygen transmission rate of packaging film (OTR), (3) product to headspace volume ratio, (4) illuminance level and (5) nitrite level during curing, was established to investigate factors affecting light-induced oxidative discoloration of cured ham (packaged in modified atmosphere of 20% carbon dioxide and balanced with nitrogen) during 14 days of chill storage. Univariate statistical analysis found significant effects of all main factors on the redness (tristimulus a-value) of the ham. Subsequently, Response Surface Modelling of the data further proved that the interactions between packaging and storage conditions are important when optimising colour stability. The measured content of oxygen in the headspace was incorporated in the model and the interaction between measured oxygen content in the headspace and the product to headspace volume ratio was found to be crucial. Thus, it is not enough to keep the headspace oxygen level low, if the headspace volume at the same time is large, there will still be sufficient oxygen for colour deteriorating processes to take place.
NASA Astrophysics Data System (ADS)
Rasam, A. R. A.; Ghazali, R.; Noor, A. M. M.; Mohd, W. M. N. W.; Hamid, J. R. A.; Bazlan, M. J.; Ahmad, N.
2014-02-01
Cholera spatial epidemiology is the study of the spread and control of the disease spatial pattern and epidemics. Previous studies have shown that multi-factorial causation such as human behaviour, ecology and other infectious risk factors influence the disease outbreaks. Thus, understanding spatial pattern and possible interrelationship factors of the outbreaks are crucial to be explored an in-depth study. This study focuses on the integration of geographical information system (GIS) and epidemiological techniques in exploratory analyzing the cholera spatial pattern and distribution in the selected district of Sabah. Spatial Statistic and Pattern tools in ArcGIS and Microsoft Excel software were utilized to map and analyze the reported cholera cases and other data used. Meanwhile, cohort study in epidemiological technique was applied to investigate multiple outcomes of the disease exposure. The general spatial pattern of cholera was highly clustered showed the disease spread easily at a place or person to others especially 1500 meters from the infected person and locations. Although the cholera outbreaks in the districts are not critical, it could be endemic at the crowded areas, unhygienic environment, and close to contaminated water. It was also strongly believed that the coastal water of the study areas has possible relationship with the cholera transmission and phytoplankton bloom since the areas recorded higher cases. GIS demonstrates a vital spatial epidemiological technique in determining the distribution pattern and elucidating the hypotheses generating of the disease. The next research would be applying some advanced geo-analysis methods and other disease risk factors for producing a significant a local scale predictive risk model of the disease in Malaysia.
How Stuttering Develops: The Multifactorial Dynamic Pathways Theory
ERIC Educational Resources Information Center
Smith, Anne; Weber, Christine
2017-01-01
Purpose: We advanced a multifactorial, dynamic account of the complex, nonlinear interactions of motor, linguistic, and emotional factors contributing to the development of stuttering. Our purpose here is to update our account as the multifactorial dynamic pathways theory. Method: We review evidence related to how stuttering develops, including…
Tomlinson, Alan; Hair, Mario; McFadyen, Angus
2013-10-01
Dry eye is a multifactorial disease which would require a broad spectrum of test measures in the monitoring of its treatment and diagnosis. However, studies have typically reported improvements in individual measures with treatment. Alternative approaches involve multiple, combined outcomes being assessed by different statistical analyses. In order to assess the effect of various statistical approaches to the use of single and combined test measures in dry eye, this review reanalyzed measures from two previous studies (osmolarity, evaporation, tear turnover rate, and lipid film quality). These analyses assessed the measures as single variables within groups, pre- and post-intervention with a lubricant supplement, by creating combinations of these variables and by validating these combinations with the combined sample of data from all groups of dry eye subjects. The effectiveness of single measures and combinations in diagnosis of dry eye was also considered. Copyright © 2013. Published by Elsevier Inc.
Lovelock, Paul K; Spurdle, Amanda B; Mok, Myth TS; Farrugia, Daniel J; Lakhani, Sunil R; Healey, Sue; Arnold, Stephen; Buchanan, Daniel; Investigators, kConFab; Couch, Fergus J; Henderson, Beric R; Goldgar, David E; Tavtigian, Sean V; Chenevix-Trench, Georgia; Brown, Melissa A
2007-01-01
Introduction Many of the DNA sequence variants identified in the breast cancer susceptibility gene BRCA1 remain unclassified in terms of their potential pathogenicity. Both multifactorial likelihood analysis and functional approaches have been proposed as a means to elucidate likely clinical significance of such variants, but analysis of the comparative value of these methods for classifying all sequence variants has been limited. Methods We have compared the results from multifactorial likelihood analysis with those from several functional analyses for the four BRCA1 sequence variants A1708E, G1738R, R1699Q, and A1708V. Results Our results show that multifactorial likelihood analysis, which incorporates sequence conservation, co-inheritance, segregation, and tumour immunohistochemical analysis, may improve classification of variants. For A1708E, previously shown to be functionally compromised, analysis of oestrogen receptor, cytokeratin 5/6, and cytokeratin 14 tumour expression data significantly strengthened the prediction of pathogenicity, giving a posterior probability of pathogenicity of 99%. For G1738R, shown to be functionally defective in this study, immunohistochemistry analysis confirmed previous findings of inconsistent 'BRCA1-like' phenotypes for the two tumours studied, and the posterior probability for this variant was 96%. The posterior probabilities of R1699Q and A1708V were 54% and 69%, respectively, only moderately suggestive of increased risk. Interestingly, results from functional analyses suggest that both of these variants have only partial functional activity. R1699Q was defective in foci formation in response to DNA damage and displayed intermediate transcriptional transactivation activity but showed no evidence for centrosome amplification. In contrast, A1708V displayed an intermediate transcriptional transactivation activity and a normal foci formation response in response to DNA damage but induced centrosome amplification. Conclusion These data highlight the need for a range of functional studies to be performed in order to identify variants with partially compromised function. The results also raise the possibility that A1708V and R1699Q may be associated with a low or moderate risk of cancer. While data pooling strategies may provide more information for multifactorial analysis to improve the interpretation of the clinical significance of these variants, it is likely that the development of current multifactorial likelihood approaches and the consideration of alternative statistical approaches will be needed to determine whether these individually rare variants do confer a low or moderate risk of breast cancer. PMID:18036263
Technical considerations to avoid delayed and non-union.
McMillan, Tristan E; Johnstone, Alan J
2017-06-01
For many years intramedullary nails have been a well accepted and successful method of diaphyseal fracture fixation. However, delayed and non unions with this technique do still occur and are associated with significant patient morbidity. The reason for this can be multi-factorial. We discuss a number of technical considerations to maximise fracture reduction, fracture stability and fracture vascularity in order to achieve bony union. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.
Prajapati, H J S; Martin, L G; Patel, T H
2014-01-01
The term vascular anomaly represents a broad spectrum of vascular pathology, including proliferating vascular tumours and vascular malformations. While the treatment of most vascular anomalies is multifactorial, interventional radiology procedures, including embolic therapy, sclerotherapy and laser coagulation among others, are playing an increasingly important role in vascular anomaly management. This review discusses the diagnosis and treatment of common vascular malformations, with emphasis on the technique, efficacy and complications of different interventional radiology procedures. PMID:24588666
Multifactorial etiology of Torus mandibularis: study of twins.
Auškalnis, Adomas; Rutkūnas, Vygandas; Bernhardt, Olaf; Šidlauskas, Mantas; Šalomskienė, Loreta; Basevičienė, Nomeda
2015-01-01
The aim of this study is to investigate the multifactorial etiology of mandibular tori analyzing the influence of genetics, occlusal overload, various clinical variables and their interactions. Overall, plaster casts of 162 twins (81 twin pairs) were analyzed for the presence or absence of mandibular tori. Atypical wear facets on canine tips or incisors were recorded to diagnose bruxism. Angle Class, any kind of anterior open bite and positive, negative or flat curve of Wilson were recorded. Zygosity determination was carried out using a DNA test. Mandibular tori were found in 56.8% of the cases. In 93.6% of all monozygotic twin pairs both individuals had or did not have mandibular tori (κ=0.96±0.04; p<0.001), compared to 79.4% concordance of mandibular tori in dizygotic co-twins (κ=0.7±0.12; p<0.001). Prevalence of mandibular tori was significantly higher in the group of bruxers (67.5%) compared to non-bruxers (31.3%) (p<0.001). Significant association between mandibular tori and negative or flat curve of Wilson in the maxillary second premolars and first molars was found (OR=2.55, 95% CI (1.19-5.46), p=0.016). In all monozygotic bruxers, 97.1% showed concordance of mandibular tori presence in both co-twins compared to 78.9% dizygotic bruxers, and this difference is statistically significant (p=0.007). Our results suggest that the mandibular tori are of a multifactorial origin. Mandibular tori seem to have genetic predisposition, and may be associated with teeth grinding as well as with negative or flat CW in region of maxillary second premolar and first molar.
Brewer, Paul; Berryman, Fiona; Baker, De; Pynsent, Paul; Gardner, Adrian
2013-11-01
Retrospective sequential patient series. To establish the relationship between the magnitude of the deformity in scoliosis and patients' perception of their condition, as measured with Scoliosis Research Society-22 scores. A total of 93 untreated patients with adolescent idiopathic scoliosis were included retrospectively. The Cobb angle was measured from a plain radiograph, and volumetric asymmetry was measured by ISIS2 surface topography. The association between Scoliosis Research Society scores for function, pain, self-image, and mental health against Cobb angle and volumetric asymmetry was investigated using the Pearson correlation coefficient. Correlation of both Cobb angle and volumetric asymmetry with function and pain was weak (all < .23); these correlation values were not statistically significant. Correlation of Cobb angle and volumetric asymmetry with self-image, was higher, although still moderate (-.37 for Cobb angle and -.44 for volumetric asymmetry). Both were statistically significant (Cobb angle, p = .0002; volumetric asymmetry; p = .00001). Cobb angle contributed 13.8% to the linear relationship with self-image, whereas volumetric asymmetry contributed 19.3%. For mental health, correlation was statistically significant with Cobb angle (p = .011) and volumetric asymmetry (p = .0005), but the correlation was low to moderate (-.26 and -.35, respectively). Cobb angle contributed 6.9% to the linear relationship with mental health, whereas volumetric asymmetry contributed 12.4%. Volumetric asymmetry correlates better with both mental health and self-image compared with Cobb angle, but the correlation was only moderate. This study suggests that a patient's own perception of self-image and mental health is multifactorial and not completely explained through present objective measurements of the size of the deformity. This helps to explain the difficulties in any objective analysis of a problem with multifactorial perception issues. Further study is required to investigate other physical aspects of the deformity that may have a role in how patients view themselves. Copyright © 2013 Scoliosis Research Society. Published by Elsevier Inc. All rights reserved.
Macpherson, Ignacio; Roqué-Sánchez, María V; Legget Bn, Finola O; Fuertes, Ferran; Segarra, Ignacio
2016-10-01
personalised support provided to women by health professionals is one of the prime factors attaining women's satisfaction during pregnancy and childbirth. However the multifactorial nature of 'satisfaction' makes difficult to assess it. Statistical multivariate analysis may be an effective technique to obtain in depth quantitative evidence of the importance of this factor and its interaction with the other factors involved. This technique allows us to estimate the importance of overall satisfaction in its context and suggest actions for healthcare services. systematic review of studies that quantitatively measure the personal relationship between women and healthcare professionals (gynecologists, obstetricians, nurse, midwifes, etc.) regarding maternity care satisfaction. The literature search focused on studies carried out between 1970 and 2014 that used multivariate analyses and included the woman-caregiver relationship as a factor of their analysis. twenty-four studies which applied various multivariate analysis tools to different periods of maternity care (antenatal, perinatal, post partum) were selected. The studies included discrete scale scores and questionnaires from women with low-risk pregnancies. The "personal relationship" factor appeared under various names: care received, personalised treatment, professional support, amongst others. The most common multivariate techniques used to assess the percentage of variance explained and the odds ratio of each factor were principal component analysis and logistic regression. the data, variables and factor analysis suggest that continuous, personalised care provided by the usual midwife and delivered within a family or a specialised setting, generates the highest level of satisfaction. In addition, these factors foster the woman's psychological and physiological recovery, often surpassing clinical action (e.g. medicalization and hospital organization) and/or physiological determinants (e.g. pain, pathologies, etc.). Copyright © 2016 Elsevier Ltd. All rights reserved.
Hamilton, Jada G; Waters, Erika A
2018-02-01
People who believe that cancer has both genetic and behavioral risk factors have more accurate mental models of cancer causation and may be more likely to engage in cancer screening behaviors than people who do not hold such multifactorial causal beliefs. This research explored possible health cognitions and emotions that might produce such differences. Using nationally representative cross-sectional data from the US Health Information National Trends Survey (N = 2719), we examined whether endorsing a multifactorial model of cancer causation was associated with perceptions of risk and other cancer-related cognitions and affect. Data were analyzed using linear regression with jackknife variance estimation and procedures to account for the complex survey design and weightings. Bivariate and multivariable analyses indicated that people who endorsed multifactorial beliefs about cancer had higher absolute risk perceptions, lower pessimism about cancer prevention, and higher worry about harm from environmental toxins that could be ingested or that emanate from consumer products (Ps < .05). Bivariate analyses indicated that multifactorial beliefs were also associated with higher feelings of risk, but multivariable analyses suggested that this effect was accounted for by the negative affect associated with reporting a family history of cancer. Multifactorial beliefs were not associated with believing that everything causes cancer or that there are too many cancer recommendations to follow (Ps > .05). Holding multifactorial causal beliefs about cancer are associated with a constellation of risk perceptions, health cognitions, and affect that may motivate cancer prevention and detection behavior. Copyright © 2017 John Wiley & Sons, Ltd.
Multifactorial analysis of human blood cell responses to clinical total body irradiation
NASA Technical Reports Server (NTRS)
Yuhas, J. M.; Stokes, T. R.; Lushbaugh, C. C.
1972-01-01
Multiple regression analysis techniques are used to study the effects of therapeutic radiation exposure, number of fractions, and time on such quantal responses as tumor control and skin injury. The potential of these methods for the analysis of human blood cell responses is demonstrated and estimates are given of the effects of total amount of exposure and time of protraction in determining the minimum white blood cell concentration observed after exposure of patients from four disease groups.
Associations between host characteristics and antimicrobial resistance of Salmonella typhimurium.
Ruddat, I; Tietze, E; Ziehm, D; Kreienbrock, L
2014-10-01
A collection of Salmonella Typhimurium isolates obtained from sporadic salmonellosis cases in humans from Lower Saxony, Germany between June 2008 and May 2010 was used to perform an exploratory risk-factor analysis on antimicrobial resistance (AMR) using comprehensive host information on sociodemographic attributes, medical history, food habits and animal contact. Multivariate resistance profiles of minimum inhibitory concentrations for 13 antimicrobial agents were analysed using a non-parametric approach with multifactorial models adjusted for phage types. Statistically significant associations were observed for consumption of antimicrobial agents, region type and three factors on egg-purchasing behaviour, indicating that besides antimicrobial use the proximity to other community members, health consciousness and other lifestyle-related attributes may play a role in the dissemination of resistances. Furthermore, a statistically significant increase in AMR from the first study year to the second year was observed.
Assessing first-stage labor progression and its relationship to complications.
Hamilton, Emily F; Warrick, Philip A; Collins, Kathleen; Smith, Samuel; Garite, Thomas J
2016-03-01
New labor curves have challenged the traditional understanding of the general pattern of dilation and descent in labor. They also revealed wide variation in the time to advance in dilation. An interval of arrest such as 4 hours did not fall beyond normal limits until dilation had reached 6 cm. Thus, the American College of Obstetricians and Gynecologists/Society for Maternal-Fetal Medicine first-stage arrest criteria, based in part on these findings, are applicable only in late labor. The wide range of time to dilate is unavoidable because cervical dilation has neither a precise nor direct relationship to time. Newer statistical techniques (multifactorial models) can improve precision by incorporating several factors that are related directly to labor progress. At each examination, the calculations adapt to the mother's current labor conditions. They produce a quantitative assessment that is expressed in percentiles. Low percentiles indicate potentially problematic labor progression. The purpose of this study was to assess the relationship between first-stage labor progress- and labor-related complications with the use of 2 different assessment methods. The first method was based on arrest of dilation definitions. The other method used percentile rankings of dilation or station based on adaptive multifactorial models. We included all 4703 cephalic-presenting, term, singleton births with electronic fetal monitoring and cord gases at 2 academic community referral hospitals in 2012 and 2013. We assessed electronic data for route of delivery, all dilation and station examinations, newborn infant status, electronic fetal monitoring tracings, and cord blood gases. The labor-related complication groups included 272 women with cesarean delivery for first-stage arrest, 558 with cesarean delivery for fetal heart rate concerns, 178 with obstetric hemorrhage, and 237 with neonatal depression, which left 3004 women in the spontaneous vaginal birth group. Receiver operating characteristic curves were constructed for each assessment method by measurement of the sensitivity for each complication vs the false-positive rate in the normal reference group. The duration of arrest at ≥6 cm dilation showed poor levels of discrimination for the cesarean delivery interventions (area under the curve, 0.55-0.65; P < .01) and no significant relationship to hemorrhage or neonatal depression. The dilation and station percentiles showed high discrimination for the cesarean delivery-related outcomes (area under the curve, 0.78-0.93; P < .01) and low discrimination for the clinical outcomes of hemorrhage and neonatal depression (area under the curve, 0.58-0.61; P < .01). Duration of arrest of dilation at ≥6 cm showed little or no discrimination for any of the complications. In comparison, percentile rankings that were based on the adaptive multifactorial models showed much higher discrimination for cesarean delivery interventions and better, but low discrimination for hemorrhage. Adaptive multifactorial models present a different method to assess labor progress. Rather than "pass/fail" criteria that are applicable only to dilation in late labor, they produce percentile rankings, assess 2 essential processes for vaginal birth (dilation and descent), and can be applied from 3 cm onward. Given the limitations of labor-progress assessment based solely on the passage of time and because of the extreme variation in decision-making for cesarean delivery for labor disorders, the types of mathematic analyses that are described in this article are logical and promising steps to help standardize labor assessment. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.
Multifactorial discrimination as a fundamental cause of mental health inequities.
Khan, Mariam; Ilcisin, Misja; Saxton, Katherine
2017-03-04
The theory of fundamental causes explains why health disparities persist over time, even as risk factors, mechanisms, and diseases change. Using an intersectional framework, we evaluated multifactorial discrimination as a fundamental cause of mental health disparities. Using baseline data from the Project STRIDE: Stress, Identity, and Mental Health study, we examined the health effects of discrimination among individuals who self-identified as lesbian, gay, or bisexual. We used logistic and linear regression to assess whether multifactorial discrimination met the four criteria designating a fundamental cause, namely that the cause: 1) influences multiple health outcomes, 2) affects multiple risk factors, 3) involves access to resources that can be leveraged to reduce consequences of disease, and 4) reproduces itself in varied contexts through changing mechanisms. Multifactorial discrimination predicted high depression scores, psychological well-being, and substance use disorder diagnosis. Discrimination was positively associated with risk factors for high depression scores: chronic strain and total number of stressful life events. Discrimination was associated with significantly lower levels of mastery and self-esteem, protective factors for depressive symptomatology. Even after controlling for risk factors, discrimination remained a significant predictor for high depression scores. Among subjects with low depression scores, multifactorial discrimination also predicted anxiety and aggregate mental health scores. Multifactorial discrimination should be considered a fundamental cause of mental health inequities and may be an important cause of broad health disparities among populations with intersecting social identities.
Factors influencing behavior guidance: a survey of practicing pediatric dentists.
Juntgen, Laura M; Sanders, Brian J; Walker, Laquia A; Jones, James E; Weddell, James A; Tomlin, Angela M; Eckert, George; Maupome, Gerardo
2013-01-01
The purpose of this study was to identify factors influencing behavior guidance technique utilization among practicing pediatric dentists and explore potential barriers to the incorporation of previously unused techniques. The data for this study were obtained from a web-based survey containing 15 multiple choice questions concerning the practitioners' past, current, and anticipated future behavior guidance technique utilization. Most respondents received hands-on training in 10 of the American Academy of Pediatric Dentistry behavior guidance techniques. The type of training was associated with the practitioners' level of comfort using a given technique upon graduation and with the current frequency of technique utilization. Residency type impacted hands-on behavior guidance training, with 39 percent of respondents reporting no intravenous sedation training. The type of practice was associated with the frequency of behavior guidance technique utilization, as was graduation decade. Currently practicing dentists cited legal concerns, parental acceptance to change, and limited resources as perceived obstacles in the incorporation of new techniques. Behavior guidance technique selection and utilization among practicing pediatric dentists was influenced by multiple factors, including advanced education training, residency type, graduation decade, and practice type. Obstacles to the incorporation of previously unused techniques appear to be multifactorial.
Universal etiology, multifactorial diseases and the constitutive model of disease classification.
Fuller, Jonathan
2018-02-01
Infectious diseases are often said to have a universal etiology, while chronic and noncommunicable diseases are said to be multifactorial in their etiology. It has been argued that the universal etiology of an infectious disease results from its classification using a monocausal disease model. In this article, I will reconstruct the monocausal model and argue that modern 'multifactorial diseases' are not monocausal by definition. 'Multifactorial diseases' are instead defined according to a constitutive disease model. On closer analysis, infectious diseases are also defined using the constitutive model rather than the monocausal model. As a result, our classification models alone cannot explain why infectious diseases have a universal etiology while chronic and noncommunicable diseases lack one. The explanation is instead provided by the Nineteenth Century germ theorists. Copyright © 2017 Elsevier Ltd. All rights reserved.
Cordell, H J; Todd, J A; Bennett, S T; Kawaguchi, Y; Farrall, M
1995-10-01
To investigate the genetic component of multifactorial diseases such as type 1 (insulin-dependent) diabetes mellitus (IDDM), models involving the joint action of several disease loci are important. These models can give increased power to detect an effect and a greater understanding of etiological mechanisms. Here, we present an extension of the maximum lod score method of N. Risch, which allows the simultaneous detection and modeling of two unlinked disease loci. Genetic constraints on the identical-by-descent sharing probabilities, analogous to the "triangle" restrictions in the single-locus method, are derived, and the size and power of the test statistics are investigated. The method is applied to affected-sib-pair data, and the joint effects of IDDM1 (HLA) and IDDM2 (the INS VNTR) and of IDDM1 and IDDM4 (FGF3-linked) are assessed with relation to the development of IDDM. In the presence of genetic heterogeneity, there is seen to be a significant advantage in analyzing more than one locus simultaneously. Analysis of these families indicates that the effects at IDDM1 and IDDM2 are well described by a multiplicative genetic model, while those at IDDM1 and IDDM4 follow a heterogeneity model.
Cordell, H J; Todd, J A; Bennett, S T; Kawaguchi, Y; Farrall, M
1995-01-01
To investigate the genetic component of multifactorial diseases such as type 1 (insulin-dependent) diabetes mellitus (IDDM), models involving the joint action of several disease loci are important. These models can give increased power to detect an effect and a greater understanding of etiological mechanisms. Here, we present an extension of the maximum lod score method of N. Risch, which allows the simultaneous detection and modeling of two unlinked disease loci. Genetic constraints on the identical-by-descent sharing probabilities, analogous to the "triangle" restrictions in the single-locus method, are derived, and the size and power of the test statistics are investigated. The method is applied to affected-sib-pair data, and the joint effects of IDDM1 (HLA) and IDDM2 (the INS VNTR) and of IDDM1 and IDDM4 (FGF3-linked) are assessed with relation to the development of IDDM. In the presence of genetic heterogeneity, there is seen to be a significant advantage in analyzing more than one locus simultaneously. Analysis of these families indicates that the effects at IDDM1 and IDDM2 are well described by a multiplicative genetic model, while those at IDDM1 and IDDM4 follow a heterogeneity model. PMID:7573054
GilPavas, Edison; Molina-Tirado, Kevin; Gómez-García, Miguel Angel
2009-01-01
An electrocoagulation process was used for the treatment of oily wastewater generated from an automotive industry in Medellín (Colombia). An electrochemical cell consisting of four parallel electrodes (Fe and Al) in bipolar configuration was implemented. A multifactorial experimental design was used for evaluating the influence of several parameters including: type and arrangement of electrodes, pH, and current density. Oil and grease removal was defined as the response variable for the statistical analysis. Additionally, the BOD(5), COD, and TOC were monitored during the treatment process. According to the results, at the optimum parameter values (current density = 4.3 mA/cm(2), distance between electrodes = 1.5 cm, Fe as anode, and pH = 12) it was possible to reach a c.a. 95% oils removal, COD and mineralization of 87.4% and 70.6%, respectively. A final biodegradability (BOD(5)/COD) of 0.54 was reached.
Neuroimaging of Cerebrovascular Disease in the Aging Brain
Gupta, Ajay; Nair, Sreejit; Schweitzer, Andrew D.; Kishore, Sirish; Johnson, Carl E.; Comunale, Joseph P.; Tsiouris, Apostolos J.; Sanelli, Pina C.
2012-01-01
Cerebrovascular disease remains a significant public health burden with its greatest impact on the elderly population. Advances in neuroimaging techniques allow detailed and sophisticated evaluation of many manifestations of cerebrovascular disease in the brain parenchyma as well as in the intracranial and extracranial vasculature. These tools continue to contribute to our understanding of the multifactorial processes that occur in the age-dependent development of cerebrovascular disease. Structural abnormalities related to vascular disease in the brain and vessels have been well characterized with CT and MRI based techniques. We review some of the pathophysiologic mechanisms in the aging brain and cerebral vasculature and the related structural abnormalities detectable on neuroimaging, including evaluation of age-related white matter changes, atherosclerosis of the cerebral vasculature, and cerebral infarction. In addition, newer neuroimaging techniques, such as diffusion tensor imaging, perfusion techniques, and assessment of cerebrovascular reserve, are also reviewed, as these techniques can detect physiologic alterations which complement the morphologic changes that cause cerebrovascular disease in the aging brain.Further investigation of these advanced imaging techniques has potential application to the understanding and diagnosis of cerebrovascular disease in the elderly. PMID:23185721
Dry Eye Treatment Based on Contact Lens Drug Delivery: A Review.
Guzman-Aranguez, Ana; Fonseca, Begoña; Carracedo, Gonzalo; Martin-Gil, Alba; Martinez-Aguila, Alejandro; Pintor, Jesús
2016-09-01
Dry eye disease affects a substantial segment of the word population with increasing frequency. It is a multifactorial disease of the ocular surface and tear film, which causes ocular discomfort, visual disturbances, and tear instability with potential damage to the cornea and conjunctiva. Because of its multifactorial etiology, the use of different pharmacological treatment for dry eye treatment has been proposed, which include anti-inflammatory molecules, lubricants or comfort agents, and secretagogues. However, in some cases these pharmacological approaches only relieve symptoms temporarily, and consequently, eye care professionals continue to have difficulties managing dry eye. To improve pharmacological therapy that allows a more efficient and long-term action, effective ocular drug delivery of the currently available drugs for dry eye treatment is required. Contact lenses are emerging as alternative ophthalmic drugs delivery systems that provide an increased residence time of the drug at the eye, thus leading to enhanced bioavailability and more convenient and efficacious therapy. In this article, we reviewed the different techniques used to prepare contact lens-based drug delivery systems and focused on articles that describe the delivery of compounds for dry eye treatment through contact lenses.
Bomer, Ilanit; Saure, Carola; Caminiti, Carolina; Ramos, Javier Gonzales; Zuccaro, Graciela; Brea, Mercedes; Bravo, Mónica; Maza, Carmen
2015-11-01
Craniopharyngioma is a histologically benign brain malformation with a fundamental role in satiety modulation, causing obesity in up to 52% of patients. To evaluate cardiovascular risk factors, body composition, resting energy expenditure (REE), and energy intake in craniopharyngioma patients and to compare the data with those from children with multifactorial obesity. All obese children and adolescents who underwent craniopharyngioma resection and a control group of children with multifactorial obesity in follow-up between May 2012 and April 2013. Anthropometric measurements, bioelectrical impedance, indirect calorimetry, energy intake, homeostatic model assessment insulin resistance (HOMA-IR), and dyslipidemia were evaluated. Twenty-three patients with craniopharyngioma and 43 controls were included. Children with craniopharyngioma-related obesity had a lower fat-free mass percentage (62.4 vs. 67.5; p=0.01) and a higher fat mass percentage (37.5 vs. 32.5; p=0.01) compared to those with multifactorial obesity. A positive association was found between %REE and %fat-free mass in subjects with multifactorial obesity (68±1% in normal REE vs. 62.6±1% in low REE; p=0.04), but not in craniopharyngioma patients (62±2.7 in normal REE vs. 61.2±1.8% in low REE; p=0.8). No differences were found in metabolic involvement or energy intake. REE was lower in craniopharyngioma patients compared to children with multifactorial obesity regardless of the amount of fat-free mass, suggesting that other factors may be responsible for the lower REE.
[Are risk factors in prenatal and perinatal period important for develompent of schizophrenia?
Ambroz, P; Janoutová, J; Machaczka, O; Kovaľová, M; Pohlídalová, A; Vařechová, K; Košta, O; Tomášková, H; Šerý, O; Hosák, L; Janout, V
Schizophrenia is an important psychical disease of multifactorial origin and not yet clear etiology. In prenatal and perinatal period some potential risk factors for schizophrenia are taken into consideration. Case-control study of 815 subjects, 407 cases and 408 controls was performed in 2013 to 2015. In this study environmental and genetic risk factors were evaluated including potential risk factors of prenatal and perinatal period. Statistically important difference was found in child-birth done by cesarean section (p = 0.009) and in patients with schizophrenia were 15.7% complications in the course of childbirth (p < 0.001). Hypoxia, passed umbilical cord were the most frequent complications. In prenatal period premature childbirth, injury and psychical complications were the most frequent. On the other hand difference in weight and length of newborns, breast feeding and infection during pregnancy were found not statistically important. In this study statistically important diference were found in way of carrying childbirth and in some complications during pregnancy and delivery. Influence of infection during pregnancy and influence of weight and length of newborn were not demonstrated.
Spinal epidural hematomas: personal experience and literature review of more than 1000 cases.
Domenicucci, Maurizio; Mancarella, Cristina; Santoro, Giorgio; Dugoni, Demo Eugenio; Ramieri, Alessandro; Arezzo, Maria Felice; Missori, Paolo
2017-08-01
OBJECTIVE The goal of this study was to identify factors that contribute to the formation of acute spinal epidural hematoma (SEH) by correlating etiology, age, site, clinical status, and treatment with immediate results and long-term outcomes. METHODS The authors reviewed their series of 15 patients who had been treated for SEH between 1996 and 2012. In addition, the authors reviewed the relevant international literature from 1869 (when SEH was first described) to 2012, collecting a total of 1010 cases. Statistical analysis was performed in 959 (95%) cases that were considered valid for assessing the incidence of age, sex, site, and clinical status at admission, correlating each of these parameters with the treatment results. Statistical analysis was also performed in 720 (71.3%) cases to study the incidence of etiological factors that favor SEH formation: coagulopathy, trauma, spinal puncture, pregnancy, and multifactorial disorders. The clinical status at admission and long-term outcome were studied for each group. Clinical status was assessed using the Neuro-Grade (NG) scale. RESULTS The mean patient age was 47.97 years (range 0-91 years), and a significant proportion of patients were male (60%, p < 0.001). A bimodal distribution has been reported for age at onset with peaks in the 2nd and 6th decades of life. The cause of the SEH was not reported in 42% of cases. The etiology concerned mainly iatrogenic factors (18%), such as coagulopathy or spinal puncture, rather than noniatrogenic factors (29%), such as genetic or metabolic coagulopathy, trauma, and pregnancy. The etiology was multifactorial in 11.1% of cases. The most common sites for SEH were C-6 (n = 293, 31%) and T-12 (n = 208, 22%), with maximum extension of 6 vertebral bodies in 720 cases (75%). At admission, 806 (84%) cases had moderate neurological impairment (NG 2 or 3), and only lumbar hematoma was associated with a good initial clinical neurological status (NG 0 or 1). Surgery was performed in 767 (80%) cases. Mortality was greater in patients older than 40 years of age (9%; p < 0.01). Sex did not influence any of these data (p > 0.05). CONCLUSIONS Factors that contribute to the formation of acute SEH are iatrogenic, not iatrogenic, or multifactorial. The treatment of choice is surgery, and the results of treatment are influenced by the patient's clinical and neurological status at admission, age, and the craniocaudal site.
Does the Use of Multifactorial Training Methods Increase Practitioners' Competence?
ERIC Educational Resources Information Center
Pittman, Corinthus Omari; Lawdis, Katina
2017-01-01
Skilled therapy practitioners are required by their governing associations to seek professional development per licensure requirements. These requirements facilitate clinical reasoning and confidence during patient care. There are limited online professional development workshops, especially ones that offer multifactorial training as an…
Hill, Keith D; Day, Lesley; Haines, Terry P
2014-01-01
Purpose To investigate previous, current, or planned participation in, and perceptions toward, multifactorial fall prevention programs such as those delivered through a falls clinic in the community setting, and to identify factors influencing older people’s intent to undertake these interventions. Design and methods Community-dwelling people aged >70 years completed a telephone survey. Participants were randomly selected from an electronic residential telephone listing, but purposeful sampling was used to include equal numbers with and without common chronic health conditions associated with fall-related hospitalization. The survey included scenarios for fall prevention interventions, including assessment/multifactorial interventions, such as those delivered through a falls clinic. Participants were asked about previous exposure to, or intent to participate in, the interventions. A path model analysis was used to identify factors associated with intent to participate in assessment/multifactorial interventions. Results Thirty of 376 participants (8.0%) reported exposure to a multifactorial falls clinic-type intervention in the past 5 years, and 16.0% expressed intention to undertake this intervention. Of the 132 participants who reported one or more falls in the past 12 months, over one-third were undecided or disagreed that a falls clinic type of intervention would be of benefit to them. Four elements from the theoretical model positively influenced intention to participate in the intervention: personal perception of intervention effectiveness, self-perceived risk of falls, self-perceived risk of injury, and inability to walk up/down steps without a handrail (P<0.05). Conclusion Multifactorial falls clinic-type interventions are not commonly accessed or considered as intended fall prevention approaches among community-dwelling older people, even among those with falls in the past 12 months. Factors identified as influencing intention to undertake these interventions may be useful in promoting or targeting these interventions. PMID:25473276
Rice, Ian M; Rice, Laura A; Motl, Robert W
2015-10-01
To examine the efficacy and feasibility of a multifactorial intervention to increase lifestyle physical activity in nonambulatory persons with multiple sclerosis (MS) based on wheelchair optimization, propulsion skill/technique training, and behavioral strategies based on social cognitive theory. Randomized controlled trial, 3-month postintervention follow-up. Home and general community, and university research laboratory. Nonambulatory individuals with MS (N=14; mean age ± SD, 53.6±8.7y) were randomly assigned to an intervention group (IG) or a control group (CG). After baseline testing, the IG participants received custom-fit, ultralightweight manual wheelchairs with propulsion/skills training, followed by 3 months of at-home use with the custom ultralightweight wheelchair and weekly phone calls to deliver support through a multifactorial intervention. The CG participants received no training and used their own wheelchairs at home during this time. All subjects were assessed at baseline and 3 months later for fatigue (Fatigue Severity Scale), upper extremity strength (digital handheld dynamometer), and propulsion technique (on a treadmill [0.5m/s] with instrumented wheels). Two 1-week bouts of physical activity were measured in both groups from home with wrist-worn accelerometry at the beginning (IG and CG in own wheelchairs) and end (IG in study wheelchair, CG in own) of the 3-month period of home use. The intervention was well tolerated, and no adverse events were reported. The IG demonstrated increased strength (P=.008) and a trend toward less fatigue (P=.068), both with large effect sizes (d>0.8), as well as reduced application of braking torque during propulsion (P=.003) with a moderate/large effect size (d=.73), compared with the CG. Findings suggest a 3-month physical activity intervention based on manual wheelchair propulsion and training is safe and feasible for some wheelchair users living with MS and may produce secondary benefits in strength, fatigue, and propulsion technique. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
Studies on the nature and managment of psoriasis.
Farber, E M
1971-06-01
Prevalence of psoriasis in Caucasians is estimated as 2 to 3 percent. Sound epidemiologic studies on a worldwide basis are needed to secure accurate prevalence rates for comparative purposes. Utilizing Stanford's psoriasis life histories records, the genetics of psoriasis has been explored by various means: statistical census data, pedigree analysis, and twin studies. This research suggests a multifactorial pattern of inheritance for psoriasis, implying that both genetic and environmental components are responsible for the manifestation of the disease. At present it is not possible to point to any single causative factor. Some of the suggested areas for research include study of uninvolved skin, growth control in the psoriatic lesion, viral causes, immunological aspects, and lipid metabolism.
Surgical management of gingival recession: A clinical update
Alghamdi, Hamdan; Babay, Nadir; Sukumaran, Anil
2009-01-01
Gingival recession is defined as the apical migration of the junctional epithelium with exposure of root surfaces. It is a common condition seen in both dentally aware populations and those with limited access to dental care. The etiology of the condition is multifactorial but is commonly associated with underlying alveolar morphology, tooth brushing, mechanical trauma and periodontal disease. Given the high rate of gingival recession defects among the general population, it is imperative that dental practitioners have an understanding of the etiology, complications and the management of the condition. The following review describes the surgical techniques to treat gingival recession. PMID:23960465
NASA Astrophysics Data System (ADS)
Kolomiets, V. I.
2018-03-01
The influence of complex influence of climatic factors (temperature, humidity) and electric mode (supply voltage) on the corrosion resistance of metallization of integrated circuits has been considered. The regression dependence of the average time of trouble-free operation t on the mentioned factors has been established in the form of a modified Arrhenius equation that is adequate in a wide range of factor values and is suitable for selecting accelerated test modes. A technique for evaluating the corrosion resistance of aluminum metallization of depressurized CMOS integrated circuits has been proposed.
RNAi control of aflatoxins in peanut plants, a multifactorial system
USDA-ARS?s Scientific Manuscript database
RNA-interference (RNAi)-mediated control of aflatoxin contamination in peanut plants is a multifactorial and hyper variable system. The use of RNAi biotechnology to silence single genes in plants has inherently high-variability among transgenic events. Also the level of expression of small interfe...
Principal components of wrist circumduction from electromagnetic surgical tracking.
Rasquinha, Brian J; Rainbow, Michael J; Zec, Michelle L; Pichora, David R; Ellis, Randy E
2017-02-01
An electromagnetic (EM) surgical tracking system was used for a functionally calibrated kinematic analysis of wrist motion. Circumduction motions were tested for differences in subject gender and for differences in the sense of the circumduction as clockwise or counter-clockwise motion. Twenty subjects were instrumented for EM tracking. Flexion-extension motion was used to identify the functional axis. Subjects performed unconstrained wrist circumduction in a clockwise and counter-clockwise sense. Data were decomposed into orthogonal flexion-extension motions and radial-ulnar deviation motions. PCA was used to concisely represent motions. Nonparametric Wilcoxon tests were used to distinguish the groups. Flexion-extension motions were projected onto a direction axis with a root-mean-square error of [Formula: see text]. Using the first three principal components, there was no statistically significant difference in gender (all [Formula: see text]). For motion sense, radial-ulnar deviation distinguished the sense of circumduction in the first principal component ([Formula: see text]) and in the third principal component ([Formula: see text]); flexion-extension distinguished the sense in the second principal component ([Formula: see text]). The clockwise sense of circumduction could be distinguished by a multifactorial combination of components; there were no gender differences in this small population. These data constitute a baseline for normal wrist circumduction. The multifactorial PCA findings suggest that a higher-dimensional method, such as manifold analysis, may be a more concise way of representing circumduction in human joints.
Diarrhoea risk factors in enterally tube fed critically ill patients: a retrospective audit.
Jack, Leanne; Coyer, Fiona; Courtney, Mary; Venkatesh, Bala
2010-12-01
Diarrhoea in the enterally tube fed (ETF) intensive care unit (ICU) patient is a multi-factorial problem. Diarrhoeal aetiologies in this patient cohort remain debatable; however, the consequences of diarrhoea have been well established and include electrolyte imbalance, dehydration, bacterial translocation, peri anal wound contamination and sleep deprivation. This study examined the incidence of diarrhoea and explored factors contributing to the development of diarrhoea in the ETF, critically ill, adult patient. After institutional ethical review and approval, a single centre medical chart audit was undertaken to examine the incidence of diarrhoea in ETF, critically ill patients. Retrospective, non-probability sequential sampling was used of all emergency admission adult ICU patients who met the inclusion/exclusion criteria. Fifty patients were audited. Faecal frequency, consistency and quantity were considered important criteria in defining ETF diarrhoea. The incidence of diarrhoea was 78%. Total patient diarrhoea days (r=0.422; p=0.02) and total diarrhoea frequency (r=0.313; p=0.027) increased when the patient was ETF for longer periods of time. Increased severity of illness, peripheral oxygen saturation (Sp02), glucose control, albumin and white cell count were found to be statistically significant factors for the development of diarrhoea. Diarrhoea in ETF critically ill patients is multi-factorial. The early identification of diarrhoea risk factors and the development of a diarrhoea risk management algorithm is recommended. Copyright © 2010. Published by Elsevier Ltd.
Waters, Erika A.; Wheeler, Courtney; Hamilton, Jada G.
2016-01-01
Background Understanding that cancer is caused by both genetic and behavioral risk factors is an important component of genomic literacy. However, a considerable percentage of people in the U.S. do not endorse such multifactorial beliefs. Methods Using nationally representative cross-sectional data from the U.S. Health Information National Trends Survey (N=2,529), we examined how information seeking, information scanning, and key information processing characteristics were associated with endorsing a multifactorial model of cancer causation. Results Multifactorial beliefs about cancer were more common among respondents who engaged in cancer information scanning (p=.001), were motivated to process health information (p=.005), and who reported a family history of cancer (p=.0002). Respondents who reported having previous negative information seeking experiences had lower odds of endorsing multifactorial beliefs (p=.01). Multifactorial beliefs were not associated with cancer information seeking, trusting cancer information obtained from the Internet, trusting cancer information from a physician, self-efficacy for obtaining cancer information, numeracy, or being aware of direct-to-consumer genetic testing (ps>.05). Conclusion Gaining additional understanding of how people access, process, and use health information will be critical for the continued development and dissemination of effective health communication interventions and for the further translation of genomics research to public health and clinical practice. PMID:27661291
Waters, Erika A; Wheeler, Courtney; Hamilton, Jada G
2016-01-01
Understanding that cancer is caused by both genetic and behavioral risk factors is an important component of genomic literacy. However, a considerable percentage of people in the United States do not endorse such multifactorial beliefs. Using nationally representative cross-sectional data from the U.S. Health Information National Trends Survey (N = 2,529), we examined how information seeking, information scanning, and key information-processing characteristics were associated with endorsing a multifactorial model of cancer causation. Multifactorial beliefs about cancer were more common among respondents who engaged in cancer information scanning (p = .001), were motivated to process health information (p = .005), and reported a family history of cancer (p = .0002). Respondents who reported having previous negative information-seeking experiences had lower odds of endorsing multifactorial beliefs (p = .01). Multifactorial beliefs were not associated with cancer information seeking, trusting cancer information obtained from the Internet, trusting cancer information from a physician, self-efficacy for obtaining cancer information, numeracy, or being aware of direct-to-consumer genetic testing (ps > .05). Gaining additional understanding of how people access, process, and use health information will be critical for the continued development and dissemination of effective health communication interventions and for the further translation of genomics research to public health and clinical practice.
Yew, Ching Ching; Alam, Mohammad Khursheed; Rahman, Shaifulizan Abdul
2016-10-01
This study is to evaluate the dental arch relationship and palatal morphology of unilateral cleft lip and palate patients by using EUROCRAN index, and to assess the factors that affect them using multivariate statistical analysis. A total of one hundred and seven patients from age five to twelve years old with non-syndromic unilateral cleft lip and palate were included in the study. These patients have received cheiloplasty and one stage palatoplasty surgery but yet to receive alveolar bone grafting procedure. Five assessors trained in the use of the EUROCRAN index underwent calibration exercise and ranked the dental arch relationships and palatal morphology of the patients' study models. For intra-rater agreement, the examiners scored the models twice, with two weeks interval in between sessions. Variable factors of the patients were collected and they included gender, site, type and, family history of unilateral cleft lip and palate; absence of lateral incisor on cleft side, cheiloplasty and palatoplasty technique used. Associations between various factors and dental arch relationships were assessed using logistic regression analysis. Dental arch relationship among unilateral cleft lip and palate in local population had relatively worse scoring than other parts of the world. Crude logistics regression analysis did not demonstrate any significant associations among the various socio-demographic factors, cheiloplasty and palatoplasty techniques used with the dental arch relationship outcome. This study has limitations that might have affected the results, example: having multiple operators performing the surgeries and the inability to access the influence of underlying genetic predisposed cranio-facial variability. These may have substantial influence on the treatment outcome. The factors that can affect unilateral cleft lip and palate treatment outcome is multifactorial in nature and remained controversial in general. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Amin, Arwa M; Sheau Chin, Lim; Teh, Chin-Hoe; Mostafa, Hamza; Mohamed Noor, Dzul Azri; Sk Abdul Kader, Muhamad Ali; Kah Hay, Yuen; Ibrahim, Baharudin
2017-11-30
Clopidogrel high on treatment platelets reactivity (HTPR) has burdened achieving optimum therapeutic outcome. Although there are known genetic and non-genetic factors associated with clopidogrel HTPR, which explain in part clopidogrel HTPR, yet, great portion remains unknown, often hindering personalizing antiplatelet therapy. Nuclear magnetic resonance ( 1 H NMR) pharmacometabolomics analysis is useful technique to phenotype drug response. We investigated using 1 H NMR analysis to phenotype clopidogrel HTPR in urine. Urine samples were collected from 71 coronary artery disease (CAD) patients who were planned for interventional angiographic procedure prior to taking 600mg clopidogrel loading dose (LD) and 6h post LD. Patients' platelets function testing was assessed with the VerifyNow ® P2Y12 assay at 6h after LD. Urine samples were analysed using 1 H NMR. Multivariate statistical analysis was used to identify metabolites associated with clopidogrel HTPR. In pre-dose samples, 16 metabolites were associated with clopidogrel HTPR. However, 18 metabolites were associated with clopidogrel HTPR in post-dose samples. The pathway analysis of the identified biomarkers reflected that multifactorial conditions are associated with clopidogrel HTPR. It also revealed the implicated role of gut microbiota in clopidogrel HTPR. Pharmacometabolomics not only discovered novel biomarkers of clopidogrel HTPR but also revealed implicated pathways and conditions. Copyright © 2017 Elsevier B.V. All rights reserved.
21 CFR 820.250 - Statistical techniques.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Statistical techniques. 820.250 Section 820.250...) MEDICAL DEVICES QUALITY SYSTEM REGULATION Statistical Techniques § 820.250 Statistical techniques. (a... statistical techniques required for establishing, controlling, and verifying the acceptability of process...
21 CFR 820.250 - Statistical techniques.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Statistical techniques. 820.250 Section 820.250...) MEDICAL DEVICES QUALITY SYSTEM REGULATION Statistical Techniques § 820.250 Statistical techniques. (a... statistical techniques required for establishing, controlling, and verifying the acceptability of process...
[FROM STATISTICAL ASSOCIATIONS TO SCIENTIFIC CAUSALITY].
Golan, Daniel; Linn, Shay
2015-06-01
The pathogenesis of most chronic diseases is complex and probably involves the interaction of multiple genetic and environmental risk factors. One way to learn about disease triggers is from statistically significant associations in epidemiological studies. However, associations do not necessarily prove causation. Associations can commonly result from bias, confounding and reverse causation. Several paradigms for causality inference have been developed. Henle-Koch postulates are mainly applied for infectious diseases. Austin Bradford Hill's criteria may serve as a practical tool to weigh the evidence regarding the probability that a single new risk factor for a given disease is indeed causal. These criteria are irrelevant for estimating the causal relationship between exposure to a risk factor and disease whenever biological causality has been previously established. Thus, it is highly probable that past exposure of an individual to definite carcinogens is related to his cancer, even without proving an association between this exposure and cancer in his group. For multifactorial diseases, Rothman's model of interacting sets of component causes can be applied.
Statistical genetics concepts and approaches in schizophrenia and related neuropsychiatric research.
Schork, Nicholas J; Greenwood, Tiffany A; Braff, David L
2007-01-01
Statistical genetics is a research field that focuses on mathematical models and statistical inference methodologies that relate genetic variations (ie, naturally occurring human DNA sequence variations or "polymorphisms") to particular traits or diseases (phenotypes) usually from data collected on large samples of families or individuals. The ultimate goal of such analysis is the identification of genes and genetic variations that influence disease susceptibility. Although of extreme interest and importance, the fact that many genes and environmental factors contribute to neuropsychiatric diseases of public health importance (eg, schizophrenia, bipolar disorder, and depression) complicates relevant studies and suggests that very sophisticated mathematical and statistical modeling may be required. In addition, large-scale contemporary human DNA sequencing and related projects, such as the Human Genome Project and the International HapMap Project, as well as the development of high-throughput DNA sequencing and genotyping technologies have provided statistical geneticists with a great deal of very relevant and appropriate information and resources. Unfortunately, the use of these resources and their interpretation are not straightforward when applied to complex, multifactorial diseases such as schizophrenia. In this brief and largely nonmathematical review of the field of statistical genetics, we describe many of the main concepts, definitions, and issues that motivate contemporary research. We also provide a discussion of the most pressing contemporary problems that demand further research if progress is to be made in the identification of genes and genetic variations that predispose to complex neuropsychiatric diseases.
Development and Validation of a Multifactorial Treatment Outcome Measure for Eating Disorders.
ERIC Educational Resources Information Center
Anderson, Drew A.; Williamson, Donald A.; Duchmann, Erich G.; Gleaves, David H.; Barbin, Jane M.
1999-01-01
Developed a brief self-report inventory to evaluate treatment outcome for anorexia and bulimia nervosa, the Multifactorial Assessment of Eating Disorders, and evaluated the instrument in a series of studies involving 1,054 women. Results support a stable factor structure and satisfactory reliability and validity, and establish normative data. (SLD)
Multifactorial disease risk calculator: Risk prediction for multifactorial disease pedigrees.
Campbell, Desmond D; Li, Yiming; Sham, Pak C
2018-03-01
Construction of multifactorial disease models from epidemiological findings and their application to disease pedigrees for risk prediction is nontrivial for all but the simplest of cases. Multifactorial Disease Risk Calculator is a web tool facilitating this. It provides a user-friendly interface, extending a reported methodology based on a liability-threshold model. Multifactorial disease models incorporating all the following features in combination are handled: quantitative risk factors (including polygenic scores), categorical risk factors (including major genetic risk loci), stratified age of onset curves, and the partition of the population variance in disease liability into genetic, shared, and unique environment effects. It allows the application of such models to disease pedigrees. Pedigree-related outputs are (i) individual disease risk for pedigree members, (ii) n year risk for unaffected pedigree members, and (iii) the disease pedigree's joint liability distribution. Risk prediction for each pedigree member is based on using the constructed disease model to appropriately weigh evidence on disease risk available from personal attributes and family history. Evidence is used to construct the disease pedigree's joint liability distribution. From this, lifetime and n year risk can be predicted. Example disease models and pedigrees are provided at the website and are used in accompanying tutorials to illustrate the features available. The website is built on an R package which provides the functionality for pedigree validation, disease model construction, and risk prediction. Website: http://grass.cgs.hku.hk:3838/mdrc/current. © 2017 WILEY PERIODICALS, INC.
Sjösten, Noora M; Vahlberg, Tero J; Kivelä, Sirkka-Liisa
2008-05-01
The aim was to determine the effects of multifactorial fall prevention on depressive symptoms among aged Finns at increased risk of falling. This study is part of a multifactorial fall prevention trial with a randomised controlled design implemented in the town of Pori, western Finland. The study population consisted of ambulatory, 65-year-old or older Finns, with moderate or high cognitive and physical abilities who had fallen at least once during the previous 12 months. The participants (n=591) were randomised into a risk-based multifactorial fall prevention programme (intervention group, IG) or into a one-time counselling group (control group, CG). The 1-year intervention included individual geriatric assessment followed by treatment recommendations, individual guidance regarding fall prevention, physical exercise in small groups twice a month, psychosocial group activities and lectures once a month, home-exercises and home hazard assessment. The outcome, depressive symptoms, was measured by the 30-item Geriatric Depression Scale (GDS). The full GDS data with no missing items were available for 464 persons. A significant decrease in depressive symptoms during the 12-month intervention was found both in IG and in CG, but the difference in change was not significant (p=0.110). However, a significant difference in change between the groups was found among men and older subjects (>or=75) in favour of the IG. Multifactorial fall prevention had no effects on depressive symptoms among the community-dwelling aged. However, men and older participants benefited from the intervention.
He, Hongbin; Argiro, Laurent; Dessein, Helia; Chevillard, Christophe
2007-01-01
FTA technology is a novel method designed to simplify the collection, shipment, archiving and purification of nucleic acids from a wide variety of biological sources. The number of punches that can normally be obtained from a single specimen card are often however, insufficient for the testing of the large numbers of loci required to identify genetic factors that control human susceptibility or resistance to multifactorial diseases. In this study, we propose an improved technique to perform large-scale SNP genotyping. We applied a whole genome amplification method to amplify DNA from buccal cell samples stabilized using FTA technology. The results show that using the improved technique it is possible to perform up to 15,000 genotypes from one buccal cell sample. Furthermore, the procedure is simple. We consider this improved technique to be a promising methods for performing large-scale SNP genotyping because the FTA technology simplifies the collection, shipment, archiving and purification of DNA, while whole genome amplification of FTA card bound DNA produces sufficient material for the determination of thousands of SNP genotypes.
Gauging Skills of Hospital Security Personnel: a Statistically-driven, Questionnaire-based Approach.
Rinkoo, Arvind Vashishta; Mishra, Shubhra; Rahesuddin; Nabi, Tauqeer; Chandra, Vidha; Chandra, Hem
2013-01-01
This study aims to gauge the technical and soft skills of the hospital security personnel so as to enable prioritization of their training needs. A cross sectional questionnaire based study was conducted in December 2011. Two separate predesigned and pretested questionnaires were used for gauging soft skills and technical skills of the security personnel. Extensive statistical analysis, including Multivariate Analysis (Pillai-Bartlett trace along with Multi-factorial ANOVA) and Post-hoc Tests (Bonferroni Test) was applied. The 143 participants performed better on the soft skills front with an average score of 6.43 and standard deviation of 1.40. The average technical skills score was 5.09 with a standard deviation of 1.44. The study avowed a need for formal hands on training with greater emphasis on technical skills. Multivariate analysis of the available data further helped in identifying 20 security personnel who should be prioritized for soft skills training and a group of 36 security personnel who should receive maximum attention during technical skills training. This statistically driven approach can be used as a prototype by healthcare delivery institutions worldwide, after situation specific customizations, to identify the training needs of any category of healthcare staff.
Gauging Skills of Hospital Security Personnel: a Statistically-driven, Questionnaire-based Approach
Rinkoo, Arvind Vashishta; Mishra, Shubhra; Rahesuddin; Nabi, Tauqeer; Chandra, Vidha; Chandra, Hem
2013-01-01
Objectives This study aims to gauge the technical and soft skills of the hospital security personnel so as to enable prioritization of their training needs. Methodology A cross sectional questionnaire based study was conducted in December 2011. Two separate predesigned and pretested questionnaires were used for gauging soft skills and technical skills of the security personnel. Extensive statistical analysis, including Multivariate Analysis (Pillai-Bartlett trace along with Multi-factorial ANOVA) and Post-hoc Tests (Bonferroni Test) was applied. Results The 143 participants performed better on the soft skills front with an average score of 6.43 and standard deviation of 1.40. The average technical skills score was 5.09 with a standard deviation of 1.44. The study avowed a need for formal hands on training with greater emphasis on technical skills. Multivariate analysis of the available data further helped in identifying 20 security personnel who should be prioritized for soft skills training and a group of 36 security personnel who should receive maximum attention during technical skills training. Conclusion This statistically driven approach can be used as a prototype by healthcare delivery institutions worldwide, after situation specific customizations, to identify the training needs of any category of healthcare staff. PMID:23559904
An, P; Rice, T; Gagnon, J; Borecki, I B; Bergeron, J; Després, J P; Leon, A S; Skinner, J S; Wilmore, J H; Bouchard, C; Rao, D C
2000-03-01
Complex segregation analyses of apolipoproteins (apo) A-1 and B-100 were performed in a sample of 520 individuals from 99 white families who participated in the HERITAGE Family Study. In these sedentary families, plasma apo A-1 and B-100 concentrations were measured before and after a 20-week endurance exercise training program. Baseline apo A-1 and B-100 were adjusted for the effects of age (age-adjusted baseline apo A-1 and B-100) and for the effects of age and BMI (age-BMI-adjusted baseline apo A-1 and B-100). The change in response to training was computed as a simple Delta (posttraining minus baseline) and was adjusted for age and the baseline (age-baseline-adjusted apo A-1 and B-100 responses to training). In the present study, a major gene could not be inferred for baseline apo A-1. Rather, we found a major effect along with a multifactorial effect accounting for 8% to 9% and 51% to 56% of the variance, respectively. In addition, no clear evidence supported a major-gene effect for its response to training, whereas the transmission of a major effect from parents to offspring was ambiguous, ie, genetic in nature or familial environmental in origin. The major effect accounted for 15% of the variance, with an additional 21% and 58% of the variance being accounted for by a multifactorial effect in parents and offspring, respectively. It is interesting to have obtained evidence of a putative recessive major locus for baseline apo B-100, which accounted for 50% to 56% of the variance, with an additional 25% to 29% of the variance due to a multifactorial effect. In contrast, no major effect for its response to training was identified, although a multifactorial effect was found that accounted for 27% of the variance. The novel findings arising from the present study are summarized as follows. Baseline apo A-1 and its response to training were influenced by a major effect and a multifactorial effect. Baseline apo B-100 was influenced by a putative major recessive gene with a multifactorial component, but its response to training was influenced solely by a multifactorial component in these sedentary families.
ERIC Educational Resources Information Center
Wallen, Eva Flygare; Mullerdorf, Maria; Christensson, Kyllike; Marcus, Claude
2013-01-01
Adolescents with intellectual disabilities (ID) have an increased prevalence of being overweight and having cardiometabolic diseases as adults, in part due to poor eating habits with an inadequate intake of vegetables. The aim of this study was to evaluate whether a multifactorial school intervention using the "Plate Model" results in…
Lelubre, Mélanie; Kamal, Susan; Genre, Noëllie; Celio, Jennifer; Gorgerat, Séverine; Hugentobler Hampai, Denise; Bourdin, Aline; Berger, Jerôme; Bugnon, Olivier; Schneider, Marie
2015-01-01
The Community Pharmacy of the Department of Ambulatory Care and Community Medicine (Policlinique Médicale Universitaire, PMU), University of Lausanne, developed and implemented an interdisciplinary medication adherence program. The program aims to support and reinforce medication adherence through a multifactorial and interdisciplinary intervention. Motivational interviewing is combined with medication adherence electronic monitors (MEMS, Aardex MWV) and a report to patient, physician, nurse, and other pharmacists. This program has become a routine activity and was extended for use with all chronic diseases. From 2004 to 2014, there were 819 patient inclusions, and 268 patients were in follow-up in 2014. This paper aims to present the organization and program's context, statistical data, published research, and future perspectives. PMID:26839879
Lelubre, Mélanie; Kamal, Susan; Genre, Noëllie; Celio, Jennifer; Gorgerat, Séverine; Hugentobler Hampai, Denise; Bourdin, Aline; Berger, Jerôme; Bugnon, Olivier; Schneider, Marie
2015-01-01
The Community Pharmacy of the Department of Ambulatory Care and Community Medicine (Policlinique Médicale Universitaire, PMU), University of Lausanne, developed and implemented an interdisciplinary medication adherence program. The program aims to support and reinforce medication adherence through a multifactorial and interdisciplinary intervention. Motivational interviewing is combined with medication adherence electronic monitors (MEMS, Aardex MWV) and a report to patient, physician, nurse, and other pharmacists. This program has become a routine activity and was extended for use with all chronic diseases. From 2004 to 2014, there were 819 patient inclusions, and 268 patients were in follow-up in 2014. This paper aims to present the organization and program's context, statistical data, published research, and future perspectives.
Quintanilha, Luís Eduardo Lavigne Paranhos; Carneiro-Campos, Luís Eduardo; Antunes, Lívia Azeredo Alves; Antunes, Leonardo Santos; Fernandes, Claudio Pinheiro; Abreu, Fernanda Volpe
2017-01-01
Hypohidrotic ectodermal dysplasia (HED) is a rare ectodermal disease with a systemic expression. Oral abnormalities are common and may include hypodontia and shape irregularities in the primary and permanent dentitions. Rehabilitation of the dental arches in pediatric patients with HED is a challenge because HED is a multifactorial disease that demands a complicated treatment approach and most dentists have limited experience or training in the necessary treatment. In addition, pediatric patients often lack the patience or ability to cooperate with complex prosthetic treatment. This case report describes a simplified technique used to fabricate complete dentures for a 4-year-old HED patient in 4 sessions.
Levine, Keith E; Redmon, Jennifer Hoponick; Elledge, Myles F; Wanigasuriya, Kamani P; Smith, Kristin; Munoz, Breda; Waduge, Vajira A; Periris-John, Roshini J; Sathiakumar, Nalini; Harrington, James M; Womack, Donna S; Wickremasinghe, Rajitha
2016-10-01
The emergence of a new form of chronic kidney disease of unknown etiology (CKDu) in Sri Lanka's North Central Province (NCP) has become a catastrophic health crisis. CKDu is characterized as slowly progressing, irreversible, and asymptomatic until late stages and, importantly, not attributed to diabetes, hypertension, or other known risk factors. It is postulated that the etiology of CKDu is multifactorial, involving genetic predisposition, nutritional and dehydration status, exposure to one or more environmental nephrotoxins, and lifestyle factors. The objective of this limited geochemical laboratory analysis was to determine the concentration of a suite of heavy metals and trace element nutrients in biological samples (human whole blood and hair) and environmental samples (drinking water, rice, soil, and freshwater fish) collected from two towns within the endemic NCP region in 2012 and 2013. This broad panel, metallomics/mineralomics approach was used to shed light on potential geochemical risk factors associated with CKDu. Based on prior literature documentation of potential nephrotoxins that may play a role in the genesis and progression of CKDu, heavy metals and fluoride were selected for analysis. The geochemical concentrations in biological and environmental media areas were quantified. Basic statistical measurements were subsequently used to compare media against applicable benchmark values, such as US soil screening levels. Cadmium, lead, and mercury were detected at concentrations exceeding US reference values in many of the biological samples, suggesting that study participants are subjected to chronic, low-level exposure to these elements. Within the limited number of environmental media samples, arsenic was determined to exceed initial risk screening and background concentration values in soil, while data collected from drinking water samples reflected the unique hydrogeochemistry of the region, including the prevalence of hard or very hard water, and fluoride, iron, manganese, sodium, and lead exceeding applicable drinking water standards in some instances. Current literature suggests that the etiology of CKDu is likely multifactorial, with no single biological or hydrogeochemical parameter directly related to disease genesis and progression. This preliminary screening identified that specific constituents may be present above levels of concern, but does not compare results against specific kidney toxicity values or cumulative risk related to a multifactorial disease process. The data collected from this limited investigation are intended to be used in the subsequent study design of a comprehensive and multifactorial etiological study of CKDu risk factors that includes sample collection, individual surveys, and laboratory analyses to more fully evaluate the potential environmental, behavioral, genetic, and lifestyle risk factors associated with CKDu.
de Groot, Maartje H.; van Campen, Jos P.; Beijnen, Jos H.; Hortobágyi, Tibor; Vuillerme, Nicolas; Lamoth, Claudine C. J.
2017-01-01
Fall prediction in geriatric patients remains challenging because the increased fall risk involves multiple, interrelated factors caused by natural aging and/or pathology. Therefore, we used a multi-factorial statistical approach to model categories of modifiable fall risk factors among geriatric patients to identify fallers with highest sensitivity and specificity with a focus on gait performance. Patients (n = 61, age = 79; 41% fallers) underwent extensive screening in three categories: (1) patient characteristics (e.g., handgrip strength, medication use, osteoporosis-related factors) (2) cognitive function (global cognition, memory, executive function), and (3) gait performance (speed-related and dynamic outcomes assessed by tri-axial trunk accelerometry). Falls were registered prospectively (mean follow-up 8.6 months) and one year retrospectively. Principal Component Analysis (PCA) on 11 gait variables was performed to determine underlying gait properties. Three fall-classification models were then built using Partial Least Squares–Discriminant Analysis (PLS-DA), with separate and combined analyses of the fall risk factors. PCA identified ‘pace’, ‘variability’, and ‘coordination’ as key properties of gait. The best PLS-DA model produced a fall classification accuracy of AUC = 0.93. The specificity of the model using patient characteristics was 60% but reached 80% when cognitive and gait outcomes were added. The inclusion of cognition and gait dynamics in fall classification models reduced misclassification. We therefore recommend assessing geriatric patients’ fall risk using a multi-factorial approach that incorporates patient characteristics, cognition, and gait dynamics. PMID:28575126
Kikkert, Lisette H J; de Groot, Maartje H; van Campen, Jos P; Beijnen, Jos H; Hortobágyi, Tibor; Vuillerme, Nicolas; Lamoth, Claudine C J
2017-01-01
Fall prediction in geriatric patients remains challenging because the increased fall risk involves multiple, interrelated factors caused by natural aging and/or pathology. Therefore, we used a multi-factorial statistical approach to model categories of modifiable fall risk factors among geriatric patients to identify fallers with highest sensitivity and specificity with a focus on gait performance. Patients (n = 61, age = 79; 41% fallers) underwent extensive screening in three categories: (1) patient characteristics (e.g., handgrip strength, medication use, osteoporosis-related factors) (2) cognitive function (global cognition, memory, executive function), and (3) gait performance (speed-related and dynamic outcomes assessed by tri-axial trunk accelerometry). Falls were registered prospectively (mean follow-up 8.6 months) and one year retrospectively. Principal Component Analysis (PCA) on 11 gait variables was performed to determine underlying gait properties. Three fall-classification models were then built using Partial Least Squares-Discriminant Analysis (PLS-DA), with separate and combined analyses of the fall risk factors. PCA identified 'pace', 'variability', and 'coordination' as key properties of gait. The best PLS-DA model produced a fall classification accuracy of AUC = 0.93. The specificity of the model using patient characteristics was 60% but reached 80% when cognitive and gait outcomes were added. The inclusion of cognition and gait dynamics in fall classification models reduced misclassification. We therefore recommend assessing geriatric patients' fall risk using a multi-factorial approach that incorporates patient characteristics, cognition, and gait dynamics.
Genetic and environmental factors in human osteoporosis.
Özbaş, Halil; Tutgun Onrat, Serap; Özdamar, Kazım
2012-12-01
Osteoporosis is a common disorder, with prolongation of the average life span it has become a major public health problem. On the formation of osteoporosis genetic factors and environmental influences could play a role then it is considered as multi-factorial. Because a variety of functions to affect susceptibility to the formation of osteoporosis VDR-F, VDR-B, COL1A1, ESR1X, ESR1P and CTR are thought to be candidate genes. In this study, the aim is to investigate the relationship between these genes polymorphism and bone mineral density (BMD) values of lumbar vertebra and femoral neck in 188 Turkish people. Lumbar spine and femoral neck BMD of the individuals included in the study were measured by the dual X-ray absorptiometry method. The genotyped polymorphisms by simultaneous amplification of five regions of the genome, containing six SNPs of interest and detecting the amplified product, using the kit MetaBone Clinical Arrays(®). Statistical analyses indicated that; VDR-B gene polymorphisms major (P = 0.013), VDR-F polymorphisms have minor (P = 0.082) effect on femur BMD. None of the other genes has any significant effect on spinal BMD. Patient age, body mass index and diet has significant effect on femoral and spinal BMD. Osteoporosis is a multi-factorial disease and many genetic and non-genetic risk factors contribute to the development of osteoporosis. Early detection of a genetic predisposition to osteoporosis should allow delay and/or limit unfavorable changes in the bone tissue.
ERIC Educational Resources Information Center
Laforest, Sophie; Lorthios-Guilledroit, Agathe; Nour, Kareen; Parisien, Manon; Fournier, Michel; Ellemberg, Dave; Guay, Danielle; Desgagnés-Cyr, Charles-Émile; Bier, Nathalie
2017-01-01
This study examined the effects on attitudes and lifestyle behavior of "Jog your Mind," a multi-factorial community-based program promoting cognitive vitality among seniors with no known cognitive impairment. A quasi-experimental study was conducted. Twenty-three community organizations were assigned either to the experimental group…
Gjertson, D W
1994-01-01
1. From a multivariate log-linear analysis of 57,303 renal transplants between 1988 and 1994, the top 10 factors influencing one-year and 3-year cadaveric graft survival rates were ranked as follows: [table: see text] 2. Center effects accounted for 30% and 28% of all assignable variations in one-year and 3-year outcomes, respectively. Although center variation dominated 32 other variables, most factors were relatively independent of transplant center. 3. Novel to our own multifactorial analyses of the UNOS Kidney Transplant Registry were 6 pretransplant factors (recipient pretransplant dialysis, pregnancy, PRA technique, donor disposition and preservation, and ABO compatibility). Survival rates over the various combinations of these new factors were not significantly different. 4. For the first time in our multivariate analyses, 4 posttransplantation factors (delayed graft function, rejection episodes prior to discharge, induction and maintenance drug therapies) were included in the log-linear model. It is noteworthy that graft survival in both transplant periods was seriously imperiled following delayed graft function or rejection prior to discharge, yet the accounting for these pseudo-outcome variables did not alter the influence of the remaining 31 transplant factors. Finally, maintenance drug therapies strongly influenced short-term outcomes but did not influence long-term results, except for a noteworthy trend toward increased survival rates for FK506 therapy.
Vranić, Andrea; Španić, Ana Marija; Carretti, Barbara; Borella, Erika
2013-11-01
Several studies have shown an increase in memory performance after teaching mnemonic techniques to older participants. However, transfer effects to non-trained tasks are generally either very small, or not found. The present study investigates the efficacy of a multifactorial memory training program for older adults living in a residential care center. The program combines teaching of memory strategies with activities based on metacognitive (metamemory) and motivational aspects. Specific training-related gains in the Immediate list recall task (criterion task), as well as transfer effects on measures of short-term memory, long-term memory, working memory, motivational (need for cognition), and metacognitive aspects (subjective measure of one's memory) were examined. Maintenance of training benefits was assessed after seven months. Fifty-one older adults living in a residential care center, with no cognitive impairments, participated in the study. Participants were randomly assigned to two programs: the experimental group attended the training program, while the active control group was involved in a program in which different psychological issues were discussed. A benefit in the criterion task and substantial general transfer effects were found for the trained group, but not for the active control, and they were maintained at the seven months follow-up. Our results suggest that training procedures, which combine teaching of strategies with metacognitive-motivational aspects, can improve cognitive functioning and attitude toward cognitive activities in older adults.
Iturria-Medina, Yasser; Carbonell, Félix M; Sotero, Roberto C; Chouinard-Decorte, Francois; Evans, Alan C
2017-05-15
Generative models focused on multifactorial causal mechanisms in brain disorders are scarce and generally based on limited data. Despite the biological importance of the multiple interacting processes, their effects remain poorly characterized from an integrative analytic perspective. Here, we propose a spatiotemporal multifactorial causal model (MCM) of brain (dis)organization and therapeutic intervention that accounts for local causal interactions, effects propagation via physical brain networks, cognitive alterations, and identification of optimum therapeutic interventions. In this article, we focus on describing the model and applying it at the population-based level for studying late onset Alzheimer's disease (LOAD). By interrelating six different neuroimaging modalities and cognitive measurements, this model accurately predicts spatiotemporal alterations in brain amyloid-β (Aβ) burden, glucose metabolism, vascular flow, resting state functional activity, structural properties, and cognitive integrity. The results suggest that a vascular dysregulation may be the most-likely initial pathologic event leading to LOAD. Nevertheless, they also suggest that LOAD it is not caused by a unique dominant biological factor (e.g. vascular or Aβ) but by the complex interplay among multiple relevant direct interactions. Furthermore, using theoretical control analysis of the identified population-based multifactorial causal network, we show the crucial advantage of using combinatorial over single-target treatments, explain why one-target Aβ based therapies might fail to improve clinical outcomes, and propose an efficiency ranking of possible LOAD interventions. Although still requiring further validation at the individual level, this work presents the first analytic framework for dynamic multifactorial brain (dis)organization that may explain both the pathologic evolution of progressive neurological disorders and operationalize the influence of multiple interventional strategies. Copyright © 2017 Elsevier Inc. All rights reserved.
2014-01-01
Background In line with a rapidly ageing global population, the rise in the frequency of falls will lead to increased healthcare and social care costs. This study will be one of the few randomized controlled trials evaluating a multifaceted falls intervention in a low-middle income, culturally-diverse older Asian community. The primary objective of our paper is to evaluate whether individually tailored multifactorial interventions will successfully reduce the number of falls among older adults. Methods Three hundred community-dwelling older Malaysian adults with a history of (i) two or more falls, or (ii) one injurious fall in the past 12 months will be recruited. Baseline assessment will include cardiovascular, frailty, fracture risk, psychological factors, gait and balance, activities of daily living and visual assessments. Fallers will be randomized into 2 groups: to receive tailored multifactorial interventions (intervention group); or given lifestyle advice with continued conventional care (control group). Multifactorial interventions will target 6 specific risk factors. All participants will be re-assessed after 12 months. The primary outcome measure will be fall recurrence, measured with monthly falls diaries. Secondary outcomes include falls risk factors; and psychological measures including fear of falling, and quality of life. Discussion Previous studies evaluating multifactorial interventions in falls have reported variable outcomes. Given likely cultural, personal, lifestyle and health service differences in Asian countries, it is vital that individually-tailored multifaceted interventions are evaluated in an Asian population to determine applicability of these interventions in our setting. If successful, these approaches have the potential for widespread application in geriatric healthcare services, will reduce the projected escalation of falls and fall-related injuries, and improve the quality of life of our older community. Trial registration ISRCTN11674947 PMID:24951180
The Mexican Cycle of Suicide: A National Analysis of Seasonality, 2000-2013
Fernández-Niño, Julián Alfredo; Astudillo-García, Claudia Iveth; Bojorquez-Chapela, Ietza; Morales-Carmona, Evangelina; Montoya-Rodriguez, Airain Alejandra; Palacio-Mejia, Lina Sofia
2016-01-01
Introduction Suicide is a complex and multifactorial phenomenon with growing importance to public health. An increase in its occurrence has been observed in Mexico over the past 10 years. The present article analyzes the secular trend in suicide at the national level between the years 2000 and 2013. Materials and Methods All suicides during the study period (n = 64,298, of which 82.11% were men) were characterized using a spectral decomposition of the time series and a wavelet analysis to evaluate the effect of seasonal changes, type of area (urban versus rural) and sex. Results A seasonal pattern was observed with statistically significant cycles every 12 months, where peaks were identified in May but only for men in urban zones as of the year 2007. In addition, specific days of the year were found to have a higher frequency of suicides, which coincided with holidays (New Year, Mother’s Day, Mexican Independence Day and Christmas). Conclusion A wavelet analysis can be used to decompose complex time series. To the best of our knowledge, this is the first application of this technique to the study of suicides in developing countries. This analysis enabled identifying a seasonal pattern among urban men in Mexico. The identification of seasonal patterns can help to create primary prevention strategies, increase the dissemination of crisis intervention strategies and promote mental health. These strategies could be emphasized during specific periods of the year and directed towards profiles with a higher risk. PMID:26752641
NASA Astrophysics Data System (ADS)
Wang, S.; Huang, G. H.; Baetz, B. W.; Cai, X. M.; Ancell, B. C.; Fan, Y. R.
2017-11-01
The ensemble Kalman filter (EnKF) is recognized as a powerful data assimilation technique that generates an ensemble of model variables through stochastic perturbations of forcing data and observations. However, relatively little guidance exists with regard to the proper specification of the magnitude of the perturbation and the ensemble size, posing a significant challenge in optimally implementing the EnKF. This paper presents a robust data assimilation system (RDAS), in which a multi-factorial design of the EnKF experiments is first proposed for hydrologic ensemble predictions. A multi-way analysis of variance is then used to examine potential interactions among factors affecting the EnKF experiments, achieving optimality of the RDAS with maximized performance of hydrologic predictions. The RDAS is applied to the Xiangxi River watershed which is the most representative watershed in China's Three Gorges Reservoir region to demonstrate its validity and applicability. Results reveal that the pairwise interaction between perturbed precipitation and streamflow observations has the most significant impact on the performance of the EnKF system, and their interactions vary dynamically across different settings of the ensemble size and the evapotranspiration perturbation. In addition, the interactions among experimental factors vary greatly in magnitude and direction depending on different statistical metrics for model evaluation including the Nash-Sutcliffe efficiency and the Box-Cox transformed root-mean-square error. It is thus necessary to test various evaluation metrics in order to enhance the robustness of hydrologic prediction systems.
Genetics of eosinophilic esophagitis
Kottyan, LC; Rothenberg, ME
2017-01-01
Eosinophilic esophagitis (EoE) is a chronic, allergic disease associated with marked mucosal eosinophil accumulation. EoE disease risk is multifactorial and includes environmental and genetic factors. This review will focus on the contribution of genetic variation to EoE risk, as well as the experimental tools and statistical methodology used to identify EoE risk loci. Specific disease-risk loci that are shared between EoE and other allergic diseases (TSLP, LRRC32) or unique to EoE (CAPN14), as well as Mendellian Disorders associated with EoE, will be reviewed in the context of the insight that they provide into the molecular pathoetiology of EoE. We will also discuss the clinical opportunities that genetic analyses provide in the form of decision support tools, molecular diagnostics, and novel therapeutic approaches. PMID:28224995
Genetics of eosinophilic esophagitis.
Kottyan, L C; Rothenberg, M E
2017-05-01
Eosinophilic esophagitis (EoE) is a chronic, allergic disease associated with marked mucosal eosinophil accumulation. EoE disease risk is multifactorial and includes environmental and genetic factors. This review will focus on the contribution of genetic variation to EoE risk, as well as the experimental tools and statistical methodology used to identify EoE risk loci. Specific disease-risk loci that are shared between EoE and other allergic diseases (TSLP, LRRC32) or unique to EoE (CAPN14), as well as Mendellian Disorders associated with EoE, will be reviewed in the context of the insight that they provide into the molecular pathoetiology of EoE. We will also discuss the clinical opportunities that genetic analyses provide in the form of decision support tools, molecular diagnostics, and novel therapeutic approaches.
Chronic progressive lymphoedema in draught horses.
de Keyser, K; Janssens, S; Buys, N
2015-05-01
The objective of this review was to summarise and evaluate the current state of knowledge about chronic progressive lymphoedema in draught horses. Clinical signs of this multifactorial disorder are mainly restricted to the lower limbs, comprising progressively deteriorating skin, swelling and deformation. Although typical lesions were first reported at the beginning of the 20th century, chronic progressive lymphoedema was recognised as a specific syndrome only in 2003, and since then research has driven forward. Despite the high prevalence in some breeds and the serious economic impact, the pathogenesis is not fully understood, and the available treatment options remain symptomatic and noncurative. There is a need to improve diagnostic techniques and to develop selection tools. © 2014 EVJ Ltd.
[The nature, diagnosis and treatment of post-concussion syndrome].
Muñoz-Céspedes, J M; Pelegrín-Valero, C; Tirapu-Ustarroz, J; Fernández-Guinea, S
1998-11-01
The relationship between brief loss of consciousness, subsequent cognitive and emotional complaints, and impact on daily functioning continues to be hotly debated. In this paper the strong variability about prevalence of the postconcussional syndrome found in several studies is outstanding and the main issues of this disagreement are suggested. Recent neuroimaging techniques are discussed and some neuropsychological measures are suggested. Currents models (organic/psychogenic) of postconcussional symptoms are reviewed, and a multifactorial model which integrates biological factors with the relevance of neuropsychological deficits--attention, memory, speed of information processing--and coping process is proposed. Finally, according with this model, we conclude with some suggestions to improve neuropsychological intervention and medical treatment of these patients.
Wang, Xun; Sun, Beibei; Liu, Boyang; Fu, Yaping; Zheng, Pan
2017-01-01
Experimental design focuses on describing or explaining the multifactorial interactions that are hypothesized to reflect the variation. The design introduces conditions that may directly affect the variation, where particular conditions are purposely selected for observation. Combinatorial design theory deals with the existence, construction and properties of systems of finite sets whose arrangements satisfy generalized concepts of balance and/or symmetry. In this work, borrowing the concept of "balance" in combinatorial design theory, a novel method for multifactorial bio-chemical experiments design is proposed, where balanced templates in combinational design are used to select the conditions for observation. Balanced experimental data that covers all the influencing factors of experiments can be obtianed for further processing, such as training set for machine learning models. Finally, a software based on the proposed method is developed for designing experiments with covering influencing factors a certain number of times.
Henneghan, Ashley; Stuifbergen, Alexa; Becker, Heather; Kesler, Shelli; King, Elisabeth
2018-04-01
Cognitive changes following breast cancer treatment are likely multifactorial and have been linked to emotional factors, biophysiological factors, and fatigue, among others. Little is known about the contributions of modifiable factors such as stress, loneliness, and sleep quality. The purpose of this study was to explore the direct and indirect effects of perceived stress, loneliness, and sleep quality on perceived cognitive function (PCF) in breast cancer survivors (BCS) after chemotherapy completion. In this observational study, BCS 6 months to 10 years post chemotherapy were recruited from the community. We measured perceived stress, loneliness, sleep quality, anxiety, depression, fatigue, and PCF. Data analyses included descriptive statistics, correlations, and mediation analyses utilizing ordinary least square regression. Ninety women who were on average 3 years post chemotherapy completion participated in the study. Moderate to largely negative correlations were found between PCF and the psychosocial and sleep variables (r values ranged from - 0.31 to - 0.70, p values < .0009). Mediation analyses revealed that stress and daytime sleepiness both directly and indirectly impact PCF and that loneliness and sleep quality only have indirect effects (through anxiety and fatigue). Our findings suggest that perceived cognitive changes following breast cancer treatment are multifactorial and that higher stress levels, loneliness, daytime sleepiness, and poorer sleep quality are linked to worse perceived cognitive functioning. Also, stress, loneliness, and sleep quality may affect cognitive functioning through a shared psychobiological pathway. Interventions targeting stress, loneliness, and sleep quality may improve perceived cognitive functioning in breast cancer survivors.
2012-01-01
Background Poor mental health is a major issue worldwide and causality is complex. For diseases with multifactorial background synergistic effects of person- and place- factors can potentially be preventive. Nature is suggested as one such positive place-factor. In this cohort study we tested the effect of defined green qualities (Serene, Space, Wild, Culture, Lush) in the environment at baseline on mental health at follow-up. We also studied interaction effects on mental health of those place factors and varied person factors (financial stress, living conditions, and physical activity). Methods Data on person factors were extracted from a longitudinal (years 1999/2000 and 2005) population health survey (n = 24945). The participants were geocoded and linked to data on green qualities from landscape assessments, and stored in the Geographical Information System (GIS). Crude odds ratios (OR) and 95% confidence intervals (CI) were calculated, and multivariate logistic analyses were performed. Results Mental health was not affected by access to the chosen green qualities, neither in terms of amount nor in terms of any specific quality. However, we found a reduced risk for poor mental health at follow-up among women, through a significant interaction effect between physical activity and access to the qualities Serene or Space. For men the tendencies were similar, though not significant. Regarding the other three green qualities, as well as amount of qualities, no statistically certain synergistic effects were found. Likewise, no significant synergies were detected between green qualities and the other person-factors. Only advanced exercise significantly reduced the risk for poor mental health among women, but not for men, compared to physical inactivity. Conclusions The results do not directly support the hypothesis of a preventive mental health effect by access to the green qualities. However, the additive effect of serene nature to physical activity contributed to better mental health at follow-up. This tendency was equal for both sexes, but statistically significant only for women. Objective landscape assessments may be important in detangling geographic determinants of health. This study stresses the importance of considering interaction effects when dealing with disorders of multifactorial background. PMID:22568888
Balch, Charles M.; Murad, Tariq M.; Soong, Seng-Jaw; Ingalls, Anna Lee; Halpern, Norman B.; Maddox, William A.
1978-01-01
A multifactorial analysis was used to identify the dominant prognostic variables affecting survival from a computerized data base of 339 melanoma patients treated at this institution during the past 17 years. Five of the 13 parameters examined simultaneously were found to independently influence five year survival rates: 1) pathological stage (I vs II, p = 0.0014), 2) lesion ulceration (present vs absent, p = 0.006), 3) surgical treatment (wide excision vs wide excision plus lymphadenectomy, p = 0.024), 4) melanoma thickness (p = 0.032), and 5) location (upper extremity vs lower extremity vs trunk vs head and neck, p = 0.038). Additional factors considered that had either indirect or no influence on survival rates were clinical stage of disease, age, sex, level of invasion, pigmentation, lymphocyte infiltration, growth pattern, and regression. Most of these latter variables derived their prognostic value from correlation with melanoma thickness, except sex which correlated with location (extremity lesions were more frequent on females, trunk lesions on males). This statistical analysis enabled us to derive a mathematical equation for predicting an individual patient's probability of five year survival. Three categories of risk were delineated by measuring tumor thickness (Breslow microstaging) in Stage I patients: 1) thin melanomas (<0.76 mm) were associated with localized disease and a 100% cure rate: 2) intermediate thickness melanomas (0.76-4.00 mm) had an increasing risk (up to 80%) of harboring regional and/or distant metastases and 3) thick melanomas (≥4.00 mm) had a 80% risk of occult distant metastases at the time of initial presentation. The level of invasion (Clark's microstaging) correlated with survival, but was less predictive than measuring tumor thickness. Within each of Clark's Level II, III and IV groups, there were gradations of thickness with statistically different survival rates. Both microstaging methods (Breslow and Clark) were less predictive factors in patients with lymph node or distant metastases. Clinical trials evaluating alternative surgical treatments or adjunctive therapy modalities for melanoma patients should incorporate these parameters into their assessment, especially in Stage I (localized) disease where tumor thickness and the anatomical site of the primary melanoma are dominant prognostic factors. PMID:736651
NASA Astrophysics Data System (ADS)
Colmenares Roldán, Gabriel Jaime; Agudelo Gomez, Liliana María; Carlos Cornelio, Jesús Antonio; Rodriguez, Luis Fernando; Pinal, Rodolfo; Hoyos Palacio, Lina Marcela
2018-03-01
Encapsulation and controlled release of substances using polymeric nanoparticles require that these have a high reproducibility, homogeneity, and control over their properties (diameter and polydispersity), especially when they are to be used in medical, pharmaceutical, or nutritional applications among others. In conventional production systems, it is tough to ensure these characteristics; hence, the cost increases when we try to control these properties. This paper shows a comparison between a recirculating system and the standard nanoprecipitation technique for producing polymeric nanoparticles. In previous investigations, we evaluate the effect of recirculating flow and the ratio between the organic and aqueous phase. For this paper, we evaluated the effect of polymer and surfactant concentrations using a multifactorial design of experiments on the recirculating system and on the standard nanoprecipitation system. The response of the design was the average diameter of the nanoparticles and polydispersity index. Finally, we found that the polymer and surfactant concentrations could change the average diameter and polydispersity index of the nanoparticles obtained. On the other hand, it was found that the effect of the polymer concentration was stronger than the surfactant concentration to reduce the average diameter of the nanoparticles. The results of the present study show that the proposed recirculation system presents a high potential to produce polymer nanoparticles with good morphological characteristics, particle size distributions in the nano range, and with a low polydispersity. The average mean size of nanoparticles of polycaprolactone for the design using the recirculating system was of 61 to 140 nm and the values of polydispersity index PDI for this design were between 0.097 and 0.22, while for the design using the standard nanoprecipitation technique, the obtained diameters were 74 to 176 nm and the polydispersity was between 0.26 and 0.41.
Whiley, Phillip J.; Parsons, Michael T.; Leary, Jennifer; Tucker, Kathy; Warwick, Linda; Dopita, Belinda; Thorne, Heather; Lakhani, Sunil R.; Goldgar, David E.; Brown, Melissa A.; Spurdle, Amanda B.
2014-01-01
Rare exonic, non-truncating variants in known cancer susceptibility genes such as BRCA1 and BRCA2 are problematic for genetic counseling and clinical management of relevant families. This study used multifactorial likelihood analysis and/or bioinformatically-directed mRNA assays to assess pathogenicity of 19 BRCA1 or BRCA2 variants identified following patient referral to clinical genetic services. Two variants were considered to be pathogenic (Class 5). BRCA1:c.4484G> C(p.Arg1495Thr) was shown to result in aberrant mRNA transcripts predicted to encode truncated proteins. The BRCA1:c.122A>G(p.His41Arg) RING-domain variant was found from multifactorial likelihood analysis to have a posterior probability of pathogenicity of 0.995, a result consistent with existing protein functional assay data indicating lost BARD1 binding and ubiquitin ligase activity. Of the remaining variants, seven were determined to be not clinically significant (Class 1), nine were likely not pathogenic (Class 2), and one was uncertain (Class 3).These results have implications for genetic counseling and medical management of families carrying these specific variants. They also provide additional multifactorial likelihood variant classifications as reference to evaluate the sensitivity and specificity of bioinformatic prediction tools and/or functional assay data in future studies. PMID:24489791
Effects of a two-school-year multifactorial back education program in elementary schoolchildren.
Geldhof, Elisabeth; Cardon, Greet; De Bourdeaudhuij, Ilse; De Clercq, Dirk
2006-08-01
A quasi-experimental pre/post design. To investigate effects of a 2-school-year multifactorial back education program on back posture knowledge and postural behavior in elementary schoolchildren. Additionally, self-reported back or neck pain and fear-avoidance beliefs were evaluated. Epidemiologic studies report mounting nonspecific back pain prevalence among youngsters, characterized by multifactorial risk factors. Study findings of school-based interventions are promising. Furthermore, biomechanical discomfort is found in the school environment. The study sample included 193 intervention children and 172 controls (baseline, 9-to-11-year-olds). The multifactorial intervention consisted of a back education program and the stimulation of postural dynamism in the class through support and environmental changes. Evaluation consisted of a questionnaire, an observation of postural behavior in the classroom, and an observation of material handling during a movement session. The intervention resulted in increased back posture knowledge (P < 0.001), improved postural behavior during material handling (P < 0.001), and decreased duration of trunk flexion (P < 0.05) and neck torsion (P < 0.05) during lesson time. The intervention did not change fear-avoidance beliefs. There was a trend for decreased pain reports in boys of the intervention group (P < 0.09). The intervention resulted in improved postural aspects related to spinal loading. The long-term effect of improved postural behavior at young age on back pain prevalence later in life is of interest for future research.
Castillo-Cadena, Julieta; Mejia-Sanchez, Fernando; López-Arriaga, Jerónimo Amado
2017-03-01
Birth defects are the number one cause of child mortality worldwide and in 2010 it was the second cause in Mexico. Congenital malformations are a public health issue, because they cause infant mortality, chronic disease and disability. The origin can be genetic, environmental or unknown causes. Among environmental contaminants, pesticides stand out. In this study, we determine the frequency and etiology of congenital malformations in newborns (NBs) of a floricultural community and we compare it with that in the urban community. For 18 months, the NBs were monitored at the Tenancingo General Hospital and the Mother and Child Gynecology and Obstetrics Hospital (IMIEM) in Toluca. The identification of these malformations was carried out in accordance with the WHO. In Tenancingo, 1149 NBs were viewed, where 20% had some kind of congenital malformations. While in the IMIEM, 5069 were reviewed and 6% had some malformation. According to the etiology, in Tenancingo, 69% were multifactorial, 28% were monogenetic and 2% were chromosomal. In the IMIEM, 47% were multifactorial, then 18.3% were monogenetic and 2.8% were chromosomal. There was a significant difference between the global frequency of malformations and the multifactorial etiology of both institutions. Our results show that congenital malformations in the NBs occurred more frequently in the floricultural zone and that because the percentage of multifactorial etiology is higher, it is likely there is an association with exposure to pesticides.
[Air-conditioner disease. Results of an industrial medicine survey (author's transl)].
Molina, C; Aiache, J M; Bedu, M; Menaut, P; Wahl, D; Brestowski, J; Grall, Y
1982-07-03
The results of a survey conducted in a company employing 1850 persons working in air-conditioned premises are reported. One hundred and five persons were examined, including 790 who mostly complained of respiratory disorders and 20 controls. Regular check-ups during the last two years have failed to reveal any serious disease. The most frequent complaints were rhinitis and tracheitis, especially among female employees. No alveolitis was observed. The finding of Bacillus subtilis in samples of ambient air and air-conditioner filters in conjunction with the presence of precipitating antibodies against crude extracts from these samples, suggested that the respiratory disorders might have been due to this microorganism. A multifactorial analysis demonstrated a statistically significant correlation between clinical symptoms and immunological disorders. The air-conditioner disease, therefore, may present as a benign condition.
Mairesse, Olivier; Hofmans, Joeri; Theuns, Peter
2008-05-01
We propose a free, easy-to-use computer program that does not requires prior knowledge of computer programming to generate and run experiments using textual or pictorial stimuli. Although the FM Experiment Builder suite was initially programmed for building and conducting FM experiments, it can also be applied for non-FM experiments that necessitate randomized, single, or multifactorial designs. The program is highly configurable, allowing multilingual use and a wide range of different response formats. The outputs of the experiments are Microsoft Excel compatible .xls files that allow easy copy-paste of the results into Weiss's FM CalSTAT program (2006) or any other statistical package. Its Java-based structure is compatible with both Windows and Macintosh operating systems, and its compactness (< 1 MB) makes it easily distributable over the Internet.
Renfro, Mindy Oxman; Fehrer, Steven
2011-01-01
Unintentional falls is an increasing public health problem as incidence of falls rises and the population ages. The Centers for Disease Control and Prevention reports that 1 in 3 adults aged 65 years and older will experience a fall this year; 20% to 30% of those who fall will sustain a moderate to severe injury. Physical therapists caring for older adults are usually engaged with these patients after the first injury fall and may have little opportunity to abate fall risk before the injuries occur. This article describes the content selection and development of a simple-to-administer, multifactorial, Fall Risk Assessment & Screening Tool (FRAST), designed specifically for use in primary care settings to identify those older adults with high fall risk. Fall Risk Assessment & Screening Tool incorporates previously validated measures within a new multifactorial tool and includes targeted recommendations for intervention. Development of the multifactorial FRAST used a 5-part process: identification of significant fall risk factors, review of best evidence, selection of items, creation of the scoring grid, and development of a recommended action plan. Fall Risk Assessment & Screening Tool has been developed to assess fall risk in the target population of older adults (older than 65 years) living and ambulating independently in the community. Many fall risk factors have been considered and 15 items selected for inclusion. Fall Risk Assessment & Screening Tool includes 4 previously validated measures to assess balance, depression, falls efficacy, and home safety. Reliability and validity studies of FRAST are under way. Fall risk for community-dwelling older adults is an urgent, multifactorial, public health problem. Providing primary care practitioners (PCPs) with a very simple screening tool is imperative. Fall Risk Assessment & Screening Tool was created to allow for safe, quick, and low-cost administration by minimally trained office staff with interpretation and follow-up provided by the PCP.
An introduction to DARC technology.
Ahmad, Syed Shoeb
2017-01-01
Glaucoma is a multi-factorial neurodegenerative disorder. The common denominator in all types of glaucomas is retinal ganglion cell death through apoptosis. However, this cellular demise in glaucoma is detected late by structural or functional analyses. There can be a 10-year delay prior to the appearance of visual field defects and pre-perimetric glaucoma is an issue still being addressed. However, a new cutting-edge technology called detection of apoptosing retinal cells (DARC) is being developed. This technique is capable of non-invasive, real-time visualization of apoptotic changes at the cellular level. It can detect glaucomatous cell damage at a very early stage, at the moment apoptosis starts, and thus management can be initiated even prior to development of visual field changes. In future, this technique will also be able to provide conclusive evidence of the effectiveness of treatment protocol and the need for any modifications which may be required. This article aims to provide a concise review of DARC technology.
[Radiation therapy in patients with inflammatory bowel disease. A review].
Jmour, Omar; Pellat, Anna; Colson-Durand, Laurianne; To, Nhu Hanh; Latorzeff, Igor; Sargos, Paul; Sobhani, Iradj; Belkacemi, Yazid
2018-05-01
Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, are multifactorial diseases characterized by a chronic intestinal inflammation. Abdominal and pelvic irradiation can result in acute or chronic digestive toxicity. A few old studies on small population samples have suggested an increase of gastro-intestinal toxicities in patients with IBD in case of irradiation. Nevertheless, the physiopathology is unknown. More recent studies, including new irradiation techniques, have shown less toxicity events in these patients with IBD. There are no recommendations for irradiation in patients with IBD. This review aims to report recent data on this topic and discuss them regarding radiation parameters. Copyright © 2018 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.
Applications of Two-Dimensional Electrophoresis Technology to the Study of Atherosclerosis
Lepedda, Antonio J.
2008-01-01
Atherosclerosis is a multifactorial disease in which hypertension, diabetes, hyperlipidemia and other risk factors are thought to play a role. However, the molecular processes underlying plaque formation and progression are not yet completely known. In the last years some researchers applied proteomics technologies for the comprehension of biochemical pathways of atherogenesis and to search new cardiovascular biomarkers to be utilized either as early diagnostic traits or as targets for new drug therapies. Due to its intrinsic complexity, the problem has been approached by different strategies, all of which have some limitations. In this review, we summarize the most common critical experimental variables in two-dimensional electrophoresis-based techniques and recent data obtained by applying proteomic approaches in the study of atherosclerosis. PMID:27683313
Lost to the NHS: a mixed methods study of why GPs leave practice early in England.
Doran, Natasha; Fox, Fiona; Rodham, Karen; Taylor, Gordon; Harris, Michael
2016-02-01
The loss of GPs in the early stages of their careers is contributing to the GP workforce crisis. Recruitment in the UK remains below the numbers needed to support the demand for GP care. To explore the reasons why GPs leave general practice early. A mixed methods study using online survey data triangulated with qualitative interviews. Participants were GPs aged <50 years who had left the English Medical Performers List in the last 5 years (2009-2014). A total of 143 early GP leavers participated in an online survey, of which 21 took part in recorded telephone interviews. Survey data were analysed using descriptive statistics, and qualitative data using thematic analysis techniques. Reasons for leaving were cumulative and multifactorial. Organisational changes to the NHS have led to an increase in administrative tasks and overall workload that is perceived by GP participants to have fundamentally changed the doctor-patient relationship. Lack of time with patients has compromised the ability to practise more patient-centred care, and, with it, GPs' sense of professional autonomy and values, resulting in diminished job satisfaction. In this context, the additional pressures of increased patient demand and the negative media portrayal left many feeling unsupported and vulnerable to burnout and ill health, and, ultimately, to the decision to leave general practice. To improve retention of young GPs, the pace of administrative change needs to be minimised and the time spent by GPs on work that is not face-to-face patient care reduced. © British Journal of General Practice 2016.
Ayele, Fenta A; Taye, Belaynew W; Ayele, Tadesse A; Gelaye, Kassahun A
2013-01-18
Dental caries in children remains a significant public health problem. It is a disease with multifactorial causes. The aim of the study was to assess the prevalence and associated factors of dental caries among children between 7 to 14 years old. A community based cross-sectional study was conducted in Gondar town from June 2011 to September 2011. A total of 842 children were involved in the study. Multi-stage sampling technique was used to select the children. Pretested and structured questionnaires were used to collect data from mothers. Clinical examination of children was done using dental caries criteria set by world health organization. Data were entered, cleaned and edited using EPI Info version 3.5.1 and exported to SPSS version 16.0 for analysis. Binary multiple logistic regression analyses was applied to test the association. Four hundred sixty three (55%) children were females. The prevalence of dental caries was 306(36.3%).The educational status of children's father (AOR=0.3, 95%CI, 0.17, 0.80), monthly household income (AOR=0.59, 95%CI, 0.01, 0.45), regular teeth brushing (AOR=0.08, 95% CI, 0.03, 0.20) and using mouth rinsing (AOR=0.40, 95% CI, 0.2, 0.80) were found statistically significantly associated with dental caries. Dental caries were high among children in Gondar town. Low socioeconomic status and poor oral hygiene practices were the influencing factors for dental caries. Oral hygiene, dietary habits and access to dental care services are supreme important for the prevention of the problem.
Abdel Messih, Hanaa A; Ishak, Rania A H; Geneidi, Ahmed S; Mansour, Samar
2017-06-01
The aim of the present work is to exclusively optimize and model the effect of phospholipid type either egg phosphatidylcholine (EPC) or soybean phosphatidylcholine (SPC), together with other formulation variables, on the development of nano-ethosomal systems for transdermal delivery of a water-soluble antiemetic drug. Tropisetron HCl (TRO) is available as hard gelatin capsules and IV injections. The transdermal delivery of TRO is considered as a novel alternative route supposing to improve BAV as well as patient convenience. TRO-loaded ethanolic vesicular systems were prepared by hot technique. The effect of formulation variables were optimized through a response surface methodology using 3 × 2 2 -level full factorial design. The concentrations of both PC (A) and ethanol (B) and PC type (C) were the factors, while entrapment efficiency (Y 1 ), vesicle size (Y 2 ), polydispersity index (Y 3 ), and zeta potential (Y 4 ) were the responses. The drug permeation across rat skin from selected formulae was studied. Particle morphology, drug-excipient interactions, and vesicle stability were also investigated. The results proved the critical role of all formulation variables on ethosomal characteristics. The suggested models for all responses showed good predictability. Only the concentration of phospholipid, irrespective to PC type, had a significant effect on the transdermal flux (p < 0.01). The ethosomal vesicles were unilamellar with a nearly spherical shape. EPC-based ethosomes proved good stability. The study suggests the applicability of statistical modeling as a promising tool for prediction of ethosomal characteristics. The ethanolic vesicles were considered as novel potential nanocarriers for accentuated transdermal TRO delivery.
Peptide assemblies: from cell scaffolds to immune adjuvants
NASA Astrophysics Data System (ADS)
Collier, Joel
2011-03-01
This talk will discuss two interrelated aspects of peptide self-assemblies in biological applications: their use as matrices for regenerative medicine, and their use as chemically defined adjuvants for directing immune responses against engineered antigens. In the first half of the presentation, the design of peptide self-assemblies as analogues for the extracellular matrix will be described, with a focus on self-assemblies displaying multiple different cell-binding peptides. We conducted multi-factorial investigations of peptide co-assemblies containing several different ligand-bearing peptides using statistical ``design of experiments'' (DoE). Using the DoE techniques of factorial experimentation and response surface modeling, we systematically explored how precise combinations of ligand-bearing peptides modulated endothelial cell growth, in the process finding interactions between ligands not previously appreciated. By investigating immune responses against the materials intended for tissue engineering applications, we discovered that the basic self-assembling peptides were minimally immunogenic or non-immunogenic, even when delivered in strong adjuvants. -But when they were appended to an appropriately restricted epitope peptide, these materials raised strong and persistent antibody responses. These responses were dependent on covalent conjugation between the epitope and self-assembling domains of the peptides, were mediated by T cells, and could be directed towards both peptide epitopes and conjugated protein antigens. In addition to their demonstrated utility as scaffolds for regenerative medicine, peptide self-assemblies may also be useful as chemically defined adjuvants for vaccines and immunotherapies. This work was funded by NIH/NIDCR (1 R21 DE017703-03), NIH/NIBIB (1 R01 EB009701-01), and NSF (CHE-0802286).
Moghaddam, Mahsa Bidgoli; Brown, Trevor M; Clausen, April; DaSilva, Trevor; Ho, Emily; Forrest, Christopher R
2014-02-01
Deformational plagiocephaly (DP) is a multifactorial non-synostotic cranial deformity with a reported incidence as high as 1 in 7 infants in North America. Treatment options have focused on non-operative interventions including head repositioning and the use of an orthotic helmet device. Previous studies have used linear and two dimensional outcome measures to assess changes in cranial symmetry after helmet therapy. Our objective was to demonstrate improvement in head shape after treatment with a cranial molding helmet by using Root Mean Square (RMS), a measure unique to 3D photogrammetry, which takes into account both changes in volume and shape over time. Three dimensional photographs were obtained before and after molding helmet treatment in 40 infants (4-10 months old) with deformational plagiocephaly. Anatomical reference planes and measurements were recorded using the 3dMD Vultus(®) analysis software. RMS was used to quantify symmetry by superimposing left and right quadrants and calculating the mean value of aggregate distances between surfaces. Over 95% of the patients demonstrated an improvement in symmetry with helmet therapy. Furthermore, when the sample of infants was divided into two treatment subgroups, a statistically significant correlation was found between the age at the beginning of treatment and the change in the RMS value. When helmet therapy was started before 7 months of age a greater improvement in symmetry was seen. This work represents application of the technique of RMS analysis to demonstrate the efficacy of treatment of deformational plagiocephaly with a cranial molding helmet. Copyright © 2014. Published by Elsevier Ltd.
Bacterial Infections and Osteoclastogenesis Regulators in Men and Women with Cholesteatoma.
Likus, Wirginia; Siemianowicz, Krzysztof; Markowski, Jarosław; Wiaderkiewicz, Jan; Kostrząb-Zdebel, Anna; Jura-Szołtys, Edyta; Dziubdziela, Włodzimierz; Wiaderkiewicz, Ryszard; Łos, Marek J
2016-06-01
One of the most distinct features of middle ear cholesteatoma is bone destruction. Aetiology of cholesteatoma is thought to be multifactorial. Endotoxins produced by bacteria are thought to initiate the inflammation process in the middle ear leading to cholesteatoma. There are physiological differences in bone metabolism between men and women. The aim of our study was the immunohistochemical evaluation of the contents of two key components of the OPG/RANK/RANKL triad-RANKL and OPG in cholesteatoma, to analyse if there are any differences between the sexes and to evaluate the bacteria species isolated from cholesteatoma just before surgical treatment and to evaluate their plausible influence on the expression of OPG and RANKL in cholesteatoma. Twenty-one adult patients with acquired cholesteatoma who underwent surgery were analysed. There were no statistically significant differences in the expression of both regulators of osteoclastogenesis between the sexes. In 38.1 % patients cholesteatoma was not infected, whereas in 61.9 % patients various bacterial infections or mycosis were found. The most frequently isolated species was Pseudomonas aeruginosa (14.29 % infections) followed by Staphylococcus aureus (9.52 % infections). There were no statistically significant differences in expression of both OPG and RANKL between uninfected and infected cholesteatomas.
Cui, Fengjie; Zhao, Liming
2012-01-01
The objective of the study was to optimize the nutrition sources in a culture medium for the production of xylanase from Penicillium sp.WX-Z1 using Plackett-Burman design and Box-Behnken design. The Plackett-Burman multifactorial design was first employed to screen the important nutrient sources in the medium for xylanase production by Penicillium sp.WX-Z1 and subsequent use of the response surface methodology (RSM) was further optimized for xylanase production by Box-Behnken design. The important nutrient sources in the culture medium, identified by the initial screening method of Placket-Burman, were wheat bran, yeast extract, NaNO3, MgSO4, and CaCl2. The optimal amounts (in g/L) for maximum production of xylanase were: wheat bran, 32.8; yeast extract, 1.02; NaNO3, 12.71; MgSO4, 0.96; and CaCl2, 1.04. Using this statistical experimental design, the xylanase production under optimal condition reached 46.50 U/mL and an increase in xylanase activity of 1.34-fold was obtained compared with the original medium for fermentation carried out in a 30-L bioreactor. PMID:22949884
Association Studies of 22 Candidate SNPs with Late-Onset Alzheimer's Disease
Figgins, Jessica A.; Minster, Ryan L.; Demirci, F. Yesim; DeKosky, Steven T.; Kamboh, M. Ilyas
2009-01-01
Alzheimer's disease (AD) is a complex and multifactorial disease with the possible involvement of several genes. With the exception of the APOE gene as a susceptibility marker, no other genes have been shown consistently to be associated with late-onset AD (LOAD). A recent genome-wide association study of 17,343 gene-based putative functional single nucleotide polymorphisms (SNPs) found 19 significant variants, including 3 linked to APOE, showing association with LOAD (Hum Mol Genet 2007; 16:865–873). We have set out to replicate the 16 new significant associations in a large case-control cohort of American Whites. Additionally, we examined six variants present in positional and/or biological candidate genes for AD. We genotyped the 22 SNPs in up to 1,009 Caucasian Americans with LOAD and up to 1,010 age-matched healthy Caucasian Americans, using 5′ nuclease assays. We did not observe a statistically significant association between the SNPs and the risk of AD, either individually or stratified by APOE. Our data suggest that the association of the studied variants with LOAD risk, if it exists, is not statistically significant in our sample. PMID:18780302
Cui, Fengjie; Zhao, Liming
2012-01-01
The objective of the study was to optimize the nutrition sources in a culture medium for the production of xylanase from Penicillium sp.WX-Z1 using Plackett-Burman design and Box-Behnken design. The Plackett-Burman multifactorial design was first employed to screen the important nutrient sources in the medium for xylanase production by Penicillium sp.WX-Z1 and subsequent use of the response surface methodology (RSM) was further optimized for xylanase production by Box-Behnken design. The important nutrient sources in the culture medium, identified by the initial screening method of Placket-Burman, were wheat bran, yeast extract, NaNO(3), MgSO(4), and CaCl(2). The optimal amounts (in g/L) for maximum production of xylanase were: wheat bran, 32.8; yeast extract, 1.02; NaNO(3), 12.71; MgSO(4), 0.96; and CaCl(2), 1.04. Using this statistical experimental design, the xylanase production under optimal condition reached 46.50 U/mL and an increase in xylanase activity of 1.34-fold was obtained compared with the original medium for fermentation carried out in a 30-L bioreactor.
Dynamics of inflammatory markers in post-acute stroke patients undergoing rehabilitation.
Manolescu, Bogdan Nicolae; Berteanu, Mihai; Dumitru, Luminița; Dinu, Horațiu; Iliescu, Alina; Fărcășanu, Ileana Cornelia; Oprea, Eliza; Vlădoiu, Suzana; Popa, Oana; Ianăș, Olga
2011-12-01
Stroke is a pathological condition associated with an enhanced inflammatory response that has a multifactorial etiology. We evaluated the dynamic of plasma concentrations of IL-1α, IL-6, IL-8, TNF-α, soluble form of intercellular adhesion molecule 1, and lipoprotein (a) [Lp(a)] during the rehabilitation of post-acute stroke patients (n = 20), in parallel with control subjects (n = 24). Stroke patients had significantly increased concentrations of IL-6, TNF-α, and Lp(a) when compared to healthy controls. It was found that the changes in the IL-6, IL-8, and TNF-α concentrations associated with the pathological condition were statistically significant (χ2 = 4.81, p = 0.028, χ2 = 10.40, p = 0.005 and χ2 = 6.73, p = 0.034, respectively). The decrease of Lp(a) during the rehabilitation had statistical significance (p = 0.043), while the decrease of IL-1α had marginal significance (p = 0.071). IL-1α, TNF-α, and Lp(a) concentrations were significantly negatively correlated with the Barthel index values, suggesting that the decrease of these inflammatory markers was beneficial for patients' recovery.
Imaging of β-cell mass and insulitis in insulin-dependent (Type 1) diabetes mellitus.
Di Gialleonardo, Valentina; de Vries, Erik F J; Di Girolamo, Marco; Quintero, Ana M; Dierckx, Rudi A J O; Signore, Alberto
2012-12-01
Insulin-dependent (type 1) diabetes mellitus is a metabolic disease with a complex multifactorial etiology and a poorly understood pathogenesis. Genetic and environmental factors cause an autoimmune reaction against pancreatic β-cells, called insulitis, confirmed in pancreatic samples obtained at autopsy. The possibility to noninvasively quantify β-cell mass in vivo would provide important biological insights and facilitate aspects of diagnosis and therapy, including follow-up of islet cell transplantation. Moreover, the availability of a noninvasive tool to quantify the extent and severity of pancreatic insulitis could be useful for understanding the natural history of human insulin-dependent (type 1) diabetes mellitus, to early diagnose children at risk to develop overt diabetes, and to select patients to be treated with immunotherapies aimed at blocking the insulitis and monitoring the efficacy of these therapies. In this review, we outline the imaging techniques currently available for in vivo, noninvasive detection of β-cell mass and insulitis. These imaging techniques include magnetic resonance imaging, ultrasound, computed tomography, bioluminescence and fluorescence imaging, and the nuclear medicine techniques positron emission tomography and single-photon emission computed tomography. Several approaches and radiopharmaceuticals for imaging β-cells and lymphocytic insulitis are reviewed in detail.
2013-01-01
Background Cognitive complaints are reported frequently after breast cancer treatments. Their association with neuropsychological (NP) test performance is not well-established. Methods Early-stage, posttreatment breast cancer patients were enrolled in a prospective, longitudinal, cohort study prior to starting endocrine therapy. Evaluation included an NP test battery and self-report questionnaires assessing symptoms, including cognitive complaints. Multivariable regression models assessed associations among cognitive complaints, mood, treatment exposures, and NP test performance. Results One hundred eighty-nine breast cancer patients, aged 21–65 years, completed the evaluation; 23.3% endorsed higher memory complaints and 19.0% reported higher executive function complaints (>1 SD above the mean for healthy control sample). Regression modeling demonstrated a statistically significant association of higher memory complaints with combined chemotherapy and radiation treatments (P = .01), poorer NP verbal memory performance (P = .02), and higher depressive symptoms (P < .001), controlling for age and IQ. For executive functioning complaints, multivariable modeling controlling for age, IQ, and other confounds demonstrated statistically significant associations with better NP visual memory performance (P = .03) and higher depressive symptoms (P < .001), whereas combined chemotherapy and radiation treatment (P = .05) approached statistical significance. Conclusions About one in five post–adjuvant treatment breast cancer patients had elevated memory and/or executive function complaints that were statistically significantly associated with domain-specific NP test performances and depressive symptoms; combined chemotherapy and radiation treatment was also statistically significantly associated with memory complaints. These results and other emerging studies suggest that subjective cognitive complaints in part reflect objective NP performance, although their etiology and biology appear to be multifactorial, motivating further transdisciplinary research. PMID:23606729
Marconcini, Simone; Covani, Ugo; Barone, Antonio; Vittorio, Orazio; Curcio, Michele; Barbuti, Serena; Scatena, Fabrizio; Felli, Lamberto; Nicolini, Claudio
2011-07-01
Periodontitis is a complex multifactorial disease and is typically polygenic in origin. Genes play a fundamental part in each biologic process forming complex networks of interactions. However, only some genes have a high number of interactions with other genes in the network and may, therefore, be considered to play an important role. In a preliminary bioinformatic analysis, five genes that showed a higher number of interactions were identified and termed leader genes. In the present study, we use real-time quantitative polymerase chain reaction (PCR) technology to evaluate the expression levels of leader genes in the leukocytes of 10 patients with refractory chronic periodontitis and compare the expression levels with those of the same genes in 24 healthy patients. Blood was collected from 24 healthy human subjects and 10 patients with refractory chronic periodontitis and placed into heparinized blood collection tubes by personnel trained in phlebotomy using a sterile technique. Blood leukocyte cells were immediately lysed by using a kit for total RNA purification from human whole blood. Complementary DNA (cDNA) synthesis was obtained from total RNA and then real-time quantitative PCR was performed. PCR efficiencies were calculated with a relative standard curve derived from a five cDNA dilution series in triplicate that gave regression coefficients >0.98 and efficiencies >96%. The standard curves were obtained using glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and growth factor receptor binding protein 2 (GRB2), casitas B-lineage lymphoma (CBL), nuclear factor-KB1 (NFKB1), and REL-A (gene for transcription factor p65) gene primers and amplified with 1.6, 8, 40, 200, and 1,000 ng/μL total cDNA. Curves obtained for each sample showed a linear relationship between RNA concentrations and the cycle threshold value of real-time quantitative PCR for all genes. Data were expressed as mean ± SE (SEM). The groups were compared to the analysis of variance. A probability value <0.01 was considered statistically significant. The present study agrees with the preliminary bioinformatics analysis. In our experiments, the association of pathology with the genes was statistically significant for GRB2 and CBL (P <0.01), and it was not statistically significant for REL-A and NFKB1. This article lends support to our preliminary hypothesis that assigned an important role in refractory aggressive periodontitis to leader genes.
Navas, Francisco Javier; Jordana, Jordi; León, José Manuel; Arando, Ander; Pizarro, Gabriela; McLean, Amy Katherine; Delgado, Juan Vicente
2017-08-01
New productive niches can offer new commercial perspectives linked to donkeys' products and human therapeutic or leisure applications. However, no assessment for selection criteria has been carried out yet. First, we assessed the animal inherent features and environmental factors that may potentially influence several cognitive processes in donkeys. Then, we aimed at describing a practical methodology to quantify such cognitive processes, seeking their inclusion in breeding and conservation programmes, through a multifactorial linear model. Sixteen cognitive process-related traits were scored on a problem-solving test in a sample of 300 Andalusian donkeys for three consecutive years from 2013 to 2015. The linear model assessed the influence and interactions of four environmental factors, sex as an animal-inherent factor, age as a covariable, and the interactions between these factors. Analyses of variance were performed with GLM procedure of SPSS Statistics for Windows, Version 24.0 software to assess the relative importance of each factor. All traits were significantly (P<0.05) affected by all factors in the model except for sex that was not significant for some of the cognitive processes, and stimulus which was not significant (P<0.05) for all of them except for the coping style related ones. The interaction between all factors within the model was non-significant (P<0.05) for almost all cognitive processes. The development of complex multifactorial models to study cognitive processes may counteract the inherent variability in behavior genetics and the estimation and prediction of related breeding parameters, key for the implementation of successful conservation programmes in apparently functionally misplaced endangered breeds. Copyright © 2017 Elsevier Ltd. All rights reserved.
Flexible ureterorenoscopy for lower pole stones: influence of the collecting system's anatomy.
Jessen, Jan Peter; Honeck, Patrick; Knoll, Thomas; Wendt-Nordahl, Gunnar
2014-02-01
The impact of renal anatomy on the success rate of flexible ureterorenoscopy (fURS) for lower pole stones is less clear than it is on shock wave lithotripsy, for which it is a recognized influence factor. We analyzed safety and efficiency of fURS using modern endoscopes for lower pole stones dependent on the collecting system's configuration. We retrospectively evaluated a consecutive sample of 111 fURS for lower pole stones at our tertiary care center between January 2010 and September 2012 from our prospectively kept database. All procedures were performed with modern flexible ureterorenoscopes, nitinol baskets, holmium laser lithotripsy, and ureteral access sheaths whenever needed. The infundibular length (IL) and width (IW) and infundibulopelvic angle (IPA) were measured and the data were stratified for stone-free status and complications classified by the Clavien-Dindo scale. Univariate and multifactorial statistical analyses were performed. Correlation of operation time (OR-time) with anatomical parameters was conducted. Ninety-eight (88.3%) of the 111 patients were stone free after a single fURS. On multifactorial analysis, the stone size and IL had significant influence on the stone-free rate (SFR) (p<0.01), whereas IW did not. An acute IPA (<30°) also had significant influence (p=0.01). The incidence of complications and OR-time were not influenced by the pelvicaliceal anatomy. fURS is a safe and efficient treatment option for lower pole kidney stones. A long infundibulum and a very acute IPA (<30°) negatively affect the SFR. However, with second look procedures, a complete stone clearance is achievable even in case of unfavorable anatomic conditions. A narrow infundibulum has no negative effect while using modern endoscopes. The complication rate is not affected by the collecting system's anatomy.
Brotnow, Line; Reiss, David; Stover, Carla S.; Ganiban, Jody; Leve, Leslie D.; Neiderhiser, Jenae M.; Shaw, Daniel S.; Stevens, Hanna E.
2015-01-01
Background Mothers’ stress in pregnancy is considered an environmental risk factor in child development. Multiple stressors may combine to increase risk, and maternal personal characteristics may offset the effects of stress. This study aimed to test the effect of 1) multifactorial prenatal stress, integrating objective “stressors” and subjective “distress” and 2) the moderating effects of maternal characteristics (perceived social support, self-esteem and specific personality traits) on infant birthweight. Method Hierarchical regression modeling was used to examine cross-sectional data on 403 birth mothers and their newborns from an adoption study. Results Distress during pregnancy showed a statistically significant association with birthweight (R2 = 0.032, F (2, 398) = 6.782, p = .001). The hierarchical regression model revealed an almost two-fold increase in variance of birthweight predicted by stressors as compared with distress measures (R2 Δ = 0.049, F (4, 394) = 5.339, p < .001). Further, maternal characteristics moderated this association (R2 Δ = 0.031, F (4, 389) = 3.413, p = .009). Specifically, the expected benefit to birthweight as a function of higher SES was observed only for mothers with lower levels of harm-avoidance and higher levels of perceived social support. Importantly, the results were not better explained by prematurity, pregnancy complications, exposure to drugs, alcohol or environmental toxins. Conclusions The findings support multidimensional theoretical models of prenatal stress. Although both objective stressors and subjectively measured distress predict birthweight, they should be considered distinct and cumulative components of stress. This study further highlights that jointly considering risk factors and protective factors in pregnancy improves the ability to predict birthweight. PMID:26544958
The Evolving Field of Wound Measurement Techniques: A Literature Review.
Khoo, Rachel; Jansen, Shirley
2016-06-01
Wound healing is a complex and multifactorial process that requires the involvement of a multidisciplinary approach. Methods of wound measurement have been developed and continually refined with the purpose of ensuring precision in wound measurement and documentation as the primary indicator of healing. This review aims to ascertain the efficacies of current wound area measurement techniques, and to highlight any perceived gaps in the literature so as to develop suggestions for future studies and practice. Med- line, PubMed, CliniKey, and CINAHL were searched using the terms "wound/ulcer measurement techniques," "wound assessment," "digi- tal planimetry," and "structured light." Articles between 2000 and 2014 were selected, and secondary searches were carried out by exam- ining the references of relevant articles. Only papers written in English were included. A universal, standardized method of wound as- sessment has not been established or proposed. At present, techniques range from the simple to the more complex - most of which have char- acteristics that allow for applicability in both rural and urban settings. Techniques covered are: ruler measurements, acetate tracings/contact planimetry, digital planimetry, and structured light devices. Conclu- sion. In reviewing the literature, the precision and reliability of digital planimetry over the more conventional methods of ruler measurements and acetate tracings are consistently demonstrated. The advent and utility of the laser or structured light approach, however, is promising, has only been analyzed by a few, and opens up the scope for further evaluation of this technique.
Survey of statistical techniques used in validation studies of air pollution prediction models
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bornstein, R D; Anderson, S F
1979-03-01
Statistical techniques used by meteorologists to validate predictions made by air pollution models are surveyed. Techniques are divided into the following three groups: graphical, tabular, and summary statistics. Some of the practical problems associated with verification are also discussed. Characteristics desired in any validation program are listed and a suggested combination of techniques that possesses many of these characteristics is presented.
The risk of familial Mediterranean fever in MEFV heterozygotes: a statistical approach.
Jéru, Isabelle; Hentgen, Véronique; Cochet, Emmanuelle; Duquesnoy, Philippe; Le Borgne, Gaëlle; Grimprel, Emmanuel; Stojanovic, Katia Stankovic; Karabina, Sonia; Grateau, Gilles; Amselem, Serge
2013-01-01
Familial Mediterranean fever (FMF) is an autosomal recessive autoinflammatory disorder due to MEFV mutations and one of the most frequent Mediterranean genetic diseases. The observation of many heterozygous patients in whom a second mutated allele was excluded led to the proposal that heterozygosity could be causal. However, heterozygosity might be coincidental in many patients due to the very high rate of mutations in Mediterranean populations. To better delineate the pathogenicity of heterozygosity in order to improve genetic counselling and disease management. Complementary statistical approaches were used: estimation of FMF prevalence at population levels, genotype comparison in siblings from 63 familial forms, and genotype study in 557 patients from four Mediterranean populations. At the population level, we did not observe any contribution of heterozygosity to disease prevalence. In affected siblings of patients carrying two MEFV mutations, 92% carry two mutated alleles, whereas 4% are heterozygous with typical FMF diagnosis. We demonstrated statistically that patients are more likely to be heterozygous than healthy individuals, as shown by the higher ratio heterozygous carriers/non carriers in patients (p<10(-7)-p<0.003). The risk for heterozygotes to develop FMF was estimated between 2.1 × 10(-3) and 5.8 × 10(-3) and the relative risk, as compared to non carriers, between 6.3 and 8.1. This is the first statistical demonstration that heterozygosity is not responsible for classical Mendelian FMF per se, but constitutes a susceptibility factor for clinically-similar multifactorial forms of the disease. We also provide a first estimate of the risk for heterozygotes to develop FMF.
Harvie, Paul; Larkin, James; Scaddan, Matt; Longstaff, Lee M; Sloan, Karen; Beaver, Richard J
2013-01-01
This study aims to evaluate component alignment in a large cohort of total knee arthroplasties (TKAs) and ascertain whether alignment in TKAs undergoing postoperative manipulation under anesthetic is significantly different from those achieving good function. A retrospective review of 281 consecutive primary TKAs was performed. All TKAs underwent computed tomographic scanning (Perth computed tomography knee protocol). Of 281 TKAs, 21 (7.4%) underwent manipulation, performed at a mean of 8.1 weeks (range, 3-14 weeks) after surgery. No statistically significant difference was seen between groups for any of 12 parameters of alignment. Postoperative stiffness with the need for manipulation under anesthetic is multifactorial in origin. This study found insufficient evidence to support the theory that component alignment contributes significantly to the etiology of this difficult problem. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.
The weaker points of fish acute toxicity tests and how tests on embryos can solve some issues.
Wedekind, Claus; von Siebenthal, Beat; Gingold, Ruth
2007-07-01
Fish acute toxicity tests play an important role in environmental risk assessment and hazard classification because they allow for first estimates of the relative toxicity of various chemicals in various species. However, such tests need to be carefully interpreted. Here we shortly summarize the main issues which are linked to the genetics and the condition of the test animals, the standardized test situations, the uncertainty about whether a given test species can be seen as representative to a given fish fauna, the often missing knowledge about possible interaction effects, especially with micropathogens, and statistical problems like small sample sizes and, in some cases, pseudoreplication. We suggest that multi-factorial embryo tests on ecologically relevant species solve many of these issues, and we shortly explain how such tests could be done to avoid the weaker points of fish acute toxicity tests.
Which is a stronger indicator of dental caries: oral hygiene, food, or beverage? A clinical study.
Jain, Poonam; Gary, Julie J
2014-01-01
Dental caries is a multifactorial disease with various risk factors. Oral hygiene and dietary factors--specifically, the consumption of snacks and beverages with added sugars--have been shown to be risk indicators for this disease. It is critical for dental professionals to understand the relative roles of each of these food categories in the dental caries process. This article presents a cross-sectional study of 76 people living in a Southern Illinois fluoridated community. The amount of sugar-sweetened beverages, snack food consumption, plaque index, and age showed statistically significant relationships with the outcome variable--dental caries (P < 0.05). The results indicated that dietary factors and oral hygiene both contribute equally to dental caries in young adults living in a fluoridated community. Sugar-sweetened beverage consumption was a much stronger indicator of dental caries than snack food consumption in our study population.
Reuben, David B; Gazarian, Priscilla; Alexander, Neil; Araujo, Katy; Baker, Dorothy; Bean, Jonathan F; Boult, Chad; Charpentier, Peter; Duncan, Pamela; Latham, Nancy; Leipzig, Rosanne M; Quintiliani, Lisa M; Storer, Thomas; McMahon, Siobhan
2017-12-01
In response to the epidemic of falls and serious falls-related injuries in older persons, in 2014, the Patient Centered Outcomes Research Institute (PCORI) and the National Institute on Aging funded a pragmatic trial, Strategies to Reduce Injuries and Develop confidence in Elders (STRIDE) to compare the effects of a multifactorial intervention with those of an enhanced usual care intervention. The STRIDE multifactorial intervention consists of five major components that registered nurses deliver in the role of falls care managers, co-managing fall risk in partnership with patients and their primary care providers (PCPs). The components include a standardized assessment of eight modifiable risk factors (medications; postural hypotension; feet and footwear; vision; vitamin D; osteoporosis; home safety; strength, gait, and balance impairment) and the use of protocols and algorithms to generate recommended management of risk factors; explanation of assessment results to the patient (and caregiver when appropriate) using basic motivational interviewing techniques to elicit patient priorities, preferences, and readiness to participate in treatments; co-creation of individualized falls care plans that patients' PCPs review, modify, and approve; implementation of the falls care plan; and ongoing monitoring of response, regularly scheduled re-assessments of fall risk, and revisions of the falls care plan. Custom-designed falls care management software facilitates risk factor assessment, the identification of recommended interventions, clinic note generation, and longitudinal care management. The trial testing the effectiveness of the STRIDE intervention is in progress, with results expected in late 2019. © 2017, Copyright the Authors Journal compilation © 2017, The American Geriatrics Society.
Fletcher, Paul; Deluiz, Daniel; Tinoco, Eduardo Mb; Ricci, John L; Tarnow, Dennis P; Tinoco, Justine Monnerat
The treatment of peri-implant disease is one of the most controversial topics in implant dentistry. The multifactorial etiology and the myriad proposed techniques for managing the problem make successful decontamination of an implant surface affected by peri-implantitis one of the more unpredictable challenges dental practitioners have to face. This article presents the first known published case report demonstrating human histologic evidence of reosseointegration using a plastic curette for mechanical debridement and dilute sodium hypochlorite, hydrogen peroxide, and sterile saline for chemical detoxification. Guided bone regeneration in the infrabony component of the peri-implantitis lesion was accomplished using calcium sulfate and bovine bone as grafting materials and a porcine collagen barrier for connective tissue and epithelial exclusion.
Learning Petri net models of non-linear gene interactions.
Mayo, Michael
2005-10-01
Understanding how an individual's genetic make-up influences their risk of disease is a problem of paramount importance. Although machine-learning techniques are able to uncover the relationships between genotype and disease, the problem of automatically building the best biochemical model or "explanation" of the relationship has received less attention. In this paper, I describe a method based on random hill climbing that automatically builds Petri net models of non-linear (or multi-factorial) disease-causing gene-gene interactions. Petri nets are a suitable formalism for this problem, because they are used to model concurrent, dynamic processes analogous to biochemical reaction networks. I show that this method is routinely able to identify perfect Petri net models for three disease-causing gene-gene interactions recently reported in the literature.
New concept in natural history and management of diabetes mellitus in thalassemia major.
Chatterjee, Ratna; Bajoria, Rekha
2009-01-01
Diabetes Mellitus is a major endocrinopathy, which occurs due transfusional haemosiderosis and is found in 20-30% of adult patients with beta-thalassaemia worldwide, accounting for significant morbidity. It is multifactorial with iron loading being the dominant cause and its management poses a clinical challenge. Diabetes in thalassaemia patients is distinct from type 2 diabetes. It is peculiar in many aspects including its pathophysiology and occurs due to insulin resistance as well as islet cell insufficiency. This article reviews the natural history of diabetes in this presentation with emphasis on prevention monitoring and management. Use of MRI techniques may be useful for future monitoring as well as biochemical monitoring to prevent complications of diabetes. Early intervention with intensified chelation may reverse pancreatic function and structural changes as evident from MRI.
Oellgaard, Jens; Gæde, Peter; Rossing, Peter; Rørth, Rasmus; Køber, Lars; Parving, Hans-Henrik; Pedersen, Oluf
2018-05-30
In type 2 diabetes mellitus, heart failure is a frequent, potentially fatal and often forgotten complication. Glucose-lowering agents and adjuvant therapies modify the risk of heart failure. We recently reported that 7.8 years of intensified compared with conventional multifactorial intervention in individuals with type 2 diabetes and microalbuminuria in the Steno-2 study reduced the risk of cardiovascular disease and prolonged life over 21.2 years of follow-up. In this post hoc analysis, we examine the impact of intensified multifactorial intervention on the risk of hospitalisation for heart failure. One hundred and sixty individuals were randomised to conventional or intensified multifactorial intervention, using sealed envelopes. The trial was conducted using the Prospective, Randomised, Open, Blinded Endpoints (PROBE) design. After 7.8 years, all individuals were offered intensified therapy and the study continued as an observational follow-up study for an additional 13.4 years. Heart-failure hospitalisations were adjudicated from patient records by an external expert committee blinded for treatment allocation. Event rates were compared using a Cox regression model adjusted for age and sex. Eighty patients were assigned to each treatment group. Ten patients undergoing intensive therapy vs 24 undergoing conventional therapy were hospitalised for heart failure during follow-up. The HR (95% CI) was 0.30 (0.14, 0.64), p = 0.002 in the intensive-therapy group compared with the conventional-therapy group. Including death in the endpoint did not lead to an alternate overall outcome; HR 0.51 (0.34, 0.76), p = 0.001. In a pooled cohort analysis, an increase in plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) during the first two years of the trial was associated with incident heart failure. Intensified, multifactorial intervention for 7.8 years in type 2 diabetic individuals with microalbuminuria reduced the risk of hospitalisation for heart failure by 70% during a total of 21.2 years of observation. ClinicalTrials.gov NCT00320008.
[Diabetes and predictive medicine--parallax of the present time].
Rybka, J
2010-04-01
Predictive genetics uses genetic testing to estimate the risk in asymptomatic persons. Since in the case of multifactorial diseases predictive genetic analysis deals with findings which allow wider interpretation, it has a higher predictive value in expressly qualified diseases (monogenous) with high penetration compared to multifactorial (polygenous) diseases with high participation of environmental factors. In most "civilisation" (multifactorial) diseases including diabetes, heredity and environmental factors do not play two separate, independent roles. Instead, their interactions play a principal role. The new classification of diabetes is based on the implementation of not only ethiopathogenetic, but also genetic research. Diabetes mellitus type 1 (DM1T) is a polygenous multifactorial disease with the genetic component carrying about one half of the risk, the non-genetic one the other half. The study of the autoimmune nature of DM1T in connection with genetic analysis is going to bring about new insights in DM1T prediction. The author presents new pieces of knowledge on molecular genetics concerning certain specific types of diabetes. Issues relating to heredity in diabetes mellitus type 2 (DM2T) are even more complex. The disease has a polygenous nature, and the phenotype of a patient with DM2T, in addition to environmental factors, involves at least three, perhaps even tens of different genetic variations. At present, results at the genom-wide level appear to be most promising. The current concept of prediabetes is a realistic foundation for our prediction and prevention of DM2T. A multifactorial, multimarker approach based on our understanding of new pathophysiological factors of DM2T, tries to outline a "map" of prediabetes physiology, and if these tests are combined with sophisticated methods of genetic forecasting of DM2T, this may represent a significant step in our methodology of diabetes prediction. So far however, predictive genetics is limited by the interpretation of genetic predisposition and individualisation of the level of risk. There is no doubt that interpretation calls for co-operation with clinicians, while results of genetic analyses should presently be not uncritically overestimated. Predictive medicine, however, unquestionably fulfills the preventive focus of modern medicine, and genetic analysis is a perspective diagnostic method.
Trombetti, A; Hars, M; Herrmann, F; Rizzoli, R; Ferrari, S
2013-03-01
This controlled intervention study in hospitalized oldest old adults showed that a multifactorial fall-and-fracture risk assessment and management program, applied in a dedicated geriatric hospital unit, was effective in improving fall-related physical and functional performances and the level of independence in activities of daily living in high-risk patients. Hospitalization affords a major opportunity for interdisciplinary cooperation to manage fall-and-fracture risk factors in older adults. This study aimed at assessing the effects on physical performances and the level of independence in activities of daily living (ADL) of a multifactorial fall-and-fracture risk assessment and management program applied in a geriatric hospital setting. A controlled intervention study was conducted among 122 geriatric inpatients (mean ± SD age, 84 ± 7 years) admitted with a fall-related diagnosis. Among them, 92 were admitted to a dedicated unit and enrolled into a multifactorial intervention program, including intensive targeted exercise. Thirty patients who received standard usual care in a general geriatric unit formed the control group. Primary outcomes included gait and balance performances and the level of independence in ADL measured 12 ± 6 days apart. Secondary outcomes included length of stay, incidence of in-hospital falls, hospital readmission, and mortality rates. Compared to the usual care group, the intervention group had significant improvements in Timed Up and Go (adjusted mean difference [AMD] = -3.7s; 95 % CI = -6.8 to -0.7; P = 0.017), Tinetti (AMD = -1.4; 95 % CI = -2.1 to -0.8; P < 0.001), and Functional Independence Measure (AMD = 6.5; 95 %CI = 0.7-12.3; P = 0.027) test performances, as well as in several gait parameters (P < 0.05). Furthermore, this program favorably impacted adverse outcomes including hospital readmission (hazard ratio = 0.3; 95 % CI = 0.1-0.9; P = 0.02). A multifactorial fall-and-fracture risk-based intervention program, applied in a dedicated geriatric hospital unit, was effective and more beneficial than usual care in improving physical parameters related to the risk of fall and disability among high-risk oldest old patients.
Davison, John; Bond, John; Dawson, Pamela; Steen, I Nicholas; Kenny, Rose Anne
2005-03-01
To determine the effectiveness of multifactorial intervention to prevent falls in cognitively intact older persons with recurrent falls. Randomised controlled trial of multifactorial (medical, physiotherapy and occupational therapy) post-fall assessment and intervention compared with conventional care. Accident & Emergency departments in a university teaching hospital and associated district general hospital. 313 cognitively intact men and women aged over 65 years presenting to Accident & Emergency with a fall or fall-related injury and at least one additional fall in the preceding year; 159 randomised to assessment and intervention and 154 to conventional care. primary outcome was the number of falls and fallers in 1 year after recruitment. Secondary outcomes included injury rates, fall-related hospital admissions, mortality and fear of falling. There were 36% fewer falls in the intervention group (relative risk 0.64, 95% confidence interval 0.46-0.90). The proportion of subjects continuing to fall (65% (94/144) compared with 68% (102/149) relative risk 0.95, 95% confidence interval 0.81-1.12), and the number of fall-related attendances and hospital admissions was not different between groups. Duration of hospital admission was reduced (mean difference admission duration 3.6 days, 95% confidence interval 0.1-7.6) and falls efficacy was better in the intervention group (mean difference in Activities Specific Balance Confidence Score of 7.5, 95% confidence interval 0.72-14.2). Multifactorial intervention is effective at reducing the fall burden in cognitively intact older persons with recurrent falls attending Accident & Emergency, but does not reduce the proportion of subjects still falling.
Orozco-Beltran, Domingo; Ruescas-Escolano, Esther; Navarro-Palazón, Ana Isabel; Cordero, Alberto; Gaubert-Tortosa, María; Navarro-Perez, Jorge; Carratalá-Munuera, Concepción; Pertusa-Martínez, Salvador; Soler-Bahilo, Enrique; Brotons-Muntó, Francisco; Bort-Cubero, Jose; Nuñez-Martinez, Miguel Angel; Bertomeu-Martinez, Vicente; Gil-Guillen, Vicente Francisco
2013-08-02
To evaluate the effectiveness of a new multifactorial intervention to improve health care for chronic ischemic heart disease patients in primary care. The strategy has two components: a) organizational for the patient/professional relationship and b) training for professionals. Experimental study. Randomized clinical trial. Follow-up period: one year. primary care, multicenter (15 health centers). For the intervention group 15 health centers are selected from those participating in ESCARVAL study. Once the center agreed to participate patients are randomly selected from the total amount of patients with ischemic heart disease registered in the electronic health records. For the control group a random sample of patients with ischemic heart disease is selected from all 72 health centers electronic records. This study aims to evaluate the efficacy of a multifactorial intervention strategy involving patients with ischemic heart disease for the improvement of the degree of control of the cardiovascular risk factors and of the quality of life, number of visits, and number of hospitalizations. NCT01826929.
Loss of delta catenin function in severe autism
Turner, Tychele N.; Sharma, Kamal; Oh, Edwin C.; Liu, Yangfan P.; Collins, Ryan L.; Sosa, Maria X.; Auer, Dallas R.; Brand, Harrison; Sanders, Stephan J.; Moreno-De-Luca, Daniel; Pihur, Vasyl; Plona, Teri; Pike, Kristen; Soppet, Daniel R.; Smith, Michael W.; Cheung, Sau Wai; Martin, Christa Lese; State, Matthew W.; Talkowski, Michael E.; Cook, Edwin; Huganir, Richard; Katsanis, Nicholas; Chakravarti, Aravinda
2015-01-01
SUMMARY Autism is a multifactorial neurodevelopmental disorder affecting more males than females; consequently, under a multifactorial genetic hypothesis, females are affected only when they cross a higher biological threshold. We hypothesize that deleterious variants at conserved residues are enriched in severely affected patients arising from FEMFs (female-enriched multiplex families) with severe disease, enhancing the detection of key autism genes in modest numbers of cases. We show the utility of this strategy by identifying missense and dosage sequence variants in the gene encoding the adhesive junction-associated delta catenin protein (CTNND2) in FEMFs and demonstrating their loss-of-function effect by functional analyses in zebrafish embryos and cultured hippocampal neurons from wildtype and Ctnnd2 null mouse embryos. Finally, through gene expression and network analyses, we highlight a critical role for CTNND2 in neuronal development and an intimate connection to chromatin biology. Our data contribute to the understanding of the genetic architecture of autism and suggest that genetic analyses of phenotypic extremes, such as FEMFs, are of innate value in multifactorial disorders. PMID:25807484
Antweiler, Ronald C.; Taylor, Howard E.
2008-01-01
The main classes of statistical treatment of below-detection limit (left-censored) environmental data for the determination of basic statistics that have been used in the literature are substitution methods, maximum likelihood, regression on order statistics (ROS), and nonparametric techniques. These treatments, along with using all instrument-generated data (even those below detection), were evaluated by examining data sets in which the true values of the censored data were known. It was found that for data sets with less than 70% censored data, the best technique overall for determination of summary statistics was the nonparametric Kaplan-Meier technique. ROS and the two substitution methods of assigning one-half the detection limit value to censored data or assigning a random number between zero and the detection limit to censored data were adequate alternatives. The use of these two substitution methods, however, requires a thorough understanding of how the laboratory censored the data. The technique of employing all instrument-generated data - including numbers below the detection limit - was found to be less adequate than the above techniques. At high degrees of censoring (greater than 70% censored data), no technique provided good estimates of summary statistics. Maximum likelihood techniques were found to be far inferior to all other treatments except substituting zero or the detection limit value to censored data.
Efficacy of a Student-Led, Community-Based, Multifactorial Fall Prevention Program: Stay in Balance.
Der Ananian, Cheryl A; Mitros, Melanie; Buman, Matthew Paul
2017-01-01
Falls are a major public health concern in older adults. Recent fall prevention guidelines recommend the use of multifactorial fall prevention programs (FPPs) that include exercise for community-dwelling older adults; however, the availability of sustainable, community-based FPPs is limited. We conducted a 24-week quasi-experimental study to evaluate the efficacy of a community-based, multifactorial FPP [Stay in Balance (SIB)] on dynamic and functional balance and muscular strength. The SIB program was delivered by allied health students and included a health education program focused on fall risk factors and a progressive exercise program emphasizing lower-extremity strength and balance. All participants initially received the 12-week SIB program, and participants were non-randomly assigned at baseline to either continue the SIB exercise program at home or as a center-based program for an additional 12 weeks. Adults aged 60 and older ( n = 69) who were at-risk of falling (fall history or 2+ fall risk factors) were recruited to participate. Mixed effects repeated measures using Statistical Application Software Proc Mixed were used to examine group, time, and group-by-time effects on dynamic balance (8-Foot Up and Go), functional balance (Berg Balance Scale), and muscular strength (30 s chair stands and 30 s arm curls). Non-normally distributed outcome variables were log-transformed. After adjusting for age, gender, and body mass index, 8-Foot Up and Go scores, improved significantly over time [ F (2,173) = 8.92, p = 0.0; T0 - T2 diff = 1.2 (1.0)]. Berg Balance Scores [ F (2,173) = 29.0, p < 0.0001; T0 - T2 diff = 4.96 (0.72)], chair stands [ F (2,171) = 10.17, p < 0.0001; T0 - T2 diff = 3.1 (0.7)], and arm curls [ F (2,171) = 12.7, p < 0.02; T0 - T2 diff = 2.7 (0.6)] also all improved significantly over time. There were no significant group-by-time effects observed for any of the outcomes. The SIB program improved dynamic and functional balance and muscular strength in older adults at-risk for falling. Our findings indicate continuing home-based strength and balance exercises at home after completion of a center-based FPP program may be an effective and feasible way to maintain improvements in balance and strength parameters.
CAPSAS: Computer Assisted Program for the Selection of Appropriate Statistics.
ERIC Educational Resources Information Center
Shermis, Mark D.; Albert, Susan L.
A computer-assisted program has been developed for the selection of statistics or statistical techniques by both students and researchers. Based on Andrews, Klem, Davidson, O'Malley and Rodgers "A Guide for Selecting Statistical Techniques for Analyzing Social Science Data," this FORTRAN-compiled interactive computer program was…
NASA Technical Reports Server (NTRS)
Park, Steve
1990-01-01
A large and diverse number of computational techniques are routinely used to process and analyze remotely sensed data. These techniques include: univariate statistics; multivariate statistics; principal component analysis; pattern recognition and classification; other multivariate techniques; geometric correction; registration and resampling; radiometric correction; enhancement; restoration; Fourier analysis; and filtering. Each of these techniques will be considered, in order.
Narendran, Rajesh C; Duarte, Rui V; Valyi, Andrea; Eldabe, Sam
2015-06-30
The aim of this study was to evaluate changes in the uptake of intrathecal baclofen (ITB) following commissioning of this therapy by the National Health Service (NHS) England in April 2013. The specific objectives of this study were: (i) to explore the gap between the need for and the actual provision of ITB services; and (ii) to compare England figures with other European countries with comparable data available. Data for ITB -related procedures were obtained from the Hospital Episode Statistics (HES) database from 2009/2010 to 2013/2014. Patients receiving ITB for the management of spasticity. The available data for implantation of ITB from 2009/2010 to 2013/2014 for the treatment of spasticity due to varied aetiologies show that there has not been an increase in uptake of this therapy. The estimated need for this treatment based on the incidence and prevalence of conditions susceptible to ITB therapy is between 4.6 and 5.7 per million population. Our analysis of the data available from the HES database showed that the actual number of implants is around 3.0 per million population. The same period 2009-2014 has seen an increase in the delivery of other neuromodulation techniques including spinal cord stimulation, deep brain stimulation and sacral nerve stimulation. There is a considerable gap between the need for and provision of ITB figures nationally. Additionally, within the same area, we have observed important differences in the ITB service delivery between the various trusts. The reasons for this can be multifactorial, including individual experience and opinions, organisational structures, resource and financial limitations. Further research analysing the efficacy and cost-effectiveness of this treatment in the UK might inform the development of Technology Appraisal Guidance for ITB, potentially leading to an improvement in service provision. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Optical coherence tomography angiography monitors human cutaneous wound healing over time.
Deegan, Anthony J; Wang, Wendy; Men, Shaojie; Li, Yuandong; Song, Shaozhen; Xu, Jingjiang; Wang, Ruikang K
2018-03-01
In vivo imaging of the complex cascade of events known to be pivotal elements in the healing of cutaneous wounds is a difficult but essential task. Current techniques are highly invasive, or lack the level of vascular and structural detail required for accurate evaluation, monitoring and treatment. We aimed to use an advanced optical coherence tomography (OCT)-based angiography (OCTA) technique for the non-invasive, high resolution imaging of cutaneous wound healing. We used a clinical prototype OCTA to image, identify and track key vascular and structural adaptations known to occur throughout the healing process. Specific vascular parameters, such as diameter and density, were measured to aid our interpretations under a spatiotemporal framework. We identified multiple distinct, yet overlapping stages, hemostasis, inflammation, proliferation, and remodeling, and demonstrated the detailed vascularization and anatomical attributes underlying the multifactorial processes of dermatologic wound healing. OCTA provides an opportunity to both qualitatively and quantitatively assess the vascular response to acute cutaneous damage and in the future, may help to ascertain wound severity and possible healing outcomes; thus, enabling more effective treatment options.
Optical coherence tomography angiography monitors human cutaneous wound healing over time
Deegan, Anthony J.; Wang, Wendy; Men, Shaojie; Li, Yuandong; Song, Shaozhen; Xu, Jingjiang
2018-01-01
Background In vivo imaging of the complex cascade of events known to be pivotal elements in the healing of cutaneous wounds is a difficult but essential task. Current techniques are highly invasive, or lack the level of vascular and structural detail required for accurate evaluation, monitoring and treatment. We aimed to use an advanced optical coherence tomography (OCT)-based angiography (OCTA) technique for the non-invasive, high resolution imaging of cutaneous wound healing. Methods We used a clinical prototype OCTA to image, identify and track key vascular and structural adaptations known to occur throughout the healing process. Specific vascular parameters, such as diameter and density, were measured to aid our interpretations under a spatiotemporal framework. Results We identified multiple distinct, yet overlapping stages, hemostasis, inflammation, proliferation, and remodeling, and demonstrated the detailed vascularization and anatomical attributes underlying the multifactorial processes of dermatologic wound healing. Conclusions OCTA provides an opportunity to both qualitatively and quantitatively assess the vascular response to acute cutaneous damage and in the future, may help to ascertain wound severity and possible healing outcomes; thus, enabling more effective treatment options. PMID:29675355
Spatial analysis of falls in an urban community of Hong Kong
Lai, Poh C; Low, Chien T; Wong, Martin; Wong, Wing C; Chan, Ming H
2009-01-01
Background Falls are an issue of great public health concern. This study focuses on outdoor falls within an urban community in Hong Kong. Urban environmental hazards are often place-specific and dependent upon the built features, landscape characteristics, and habitual activities. Therefore, falls must be examined with respect to local situations. Results This paper uses spatial analysis methods to map fall occurrences and examine possible environmental attributes of falls in an urban community of Hong Kong. The Nearest neighbour hierarchical (Nnh) and Standard Deviational Ellipse (SDE) techniques can offer additional insights about the circumstances and environmental factors that contribute to falls. The results affirm the multi-factorial nature of falls at specific locations and for selected groups of the population. Conclusion The techniques to detect hot spots of falls yield meaningful results that enable the identification of high risk locations. The combined use of descriptive and spatial analyses can be beneficial to policy makers because different preventive measures can be devised based on the types of environmental risk factors identified. The analyses are also important preludes to establishing research hypotheses for more focused studies. PMID:19291326
El Mofty, Medhat; Essmat, Samia; Youssef, Randa; Sobeih, Sherine; Mahgoub, Doaa; Ossama, Sherine; Saad, Akmal; El Tawdy, Amira; Mashaly, Heba M; Saney, Iman; Helal, Rana; Shaker, Olfat
2016-11-01
Pathogenesis of vitiligo is believed to be multifactorial disease with a wide variety of therapeutic modalities. The aim of this work is to assess the efficacy of oral mini-pulse steroids (OMP) plus Nb-U.V.B in comparison to OMP alone and Nb-U.V.B alone in treating stable vitiligo. A prospective randomized controlled study including 45 patients categorized into three groups receiving therapy for 3 months; Group A received Nb-U.V.B plus OMP, Group B received OMP alone while Group C received Nb-U.V.B alone. Clinical assessment and PCR evaluation of bFGF, ICAM1, and ELISA for AMA were done. Patients receiving Nb-U.V.B plus OMP and using Nb-U.V.B alone gave statistically significant clinical response than those treated with OMP alone. Statistically significant rise of BFGF was noticed after treatment with Nb-U.V.B plus OMP and with Nb-U.V.B alone. Patients treated with OMP alone and with Nb-U.V.B alone showed statistically significant drop of ICAM-1 after therapy. NB-U.V.B plus OMP and Nb-U.V.B alone were found to be clinically superior over OMP alone in treating stable vitiligo patients, hence suggesting that adding OMP to Nb-U.V.B can maintain clinical and laboratory success for a longer period of time and with less relapse. © 2016 Wiley Periodicals, Inc.
Metamodels for Computer-Based Engineering Design: Survey and Recommendations
NASA Technical Reports Server (NTRS)
Simpson, Timothy W.; Peplinski, Jesse; Koch, Patrick N.; Allen, Janet K.
1997-01-01
The use of statistical techniques to build approximations of expensive computer analysis codes pervades much of todays engineering design. These statistical approximations, or metamodels, are used to replace the actual expensive computer analyses, facilitating multidisciplinary, multiobjective optimization and concept exploration. In this paper we review several of these techniques including design of experiments, response surface methodology, Taguchi methods, neural networks, inductive learning, and kriging. We survey their existing application in engineering design and then address the dangers of applying traditional statistical techniques to approximate deterministic computer analysis codes. We conclude with recommendations for the appropriate use of statistical approximation techniques in given situations and how common pitfalls can be avoided.
Batchelor, Frances A; Hill, Keith D; Mackintosh, Shylie F; Said, Catherine M; Whitehead, Craig H
2012-09-01
To determine whether a multifactorial falls prevention program reduces falls in people with stroke at risk of recurrent falls and whether this program leads to improvements in gait, balance, strength, and fall-related efficacy. A single blind, multicenter, randomized controlled trial with 12-month follow-up. Participants were recruited after discharge from rehabilitation and followed up in the community. Participants (N=156) were people with stroke at risk of recurrent falls being discharged home from rehabilitation. Tailored multifactorial falls prevention program and usual care (n=71) or control (usual care, n=85). Primary outcomes were rate of falls and proportion of fallers. Secondary outcomes included injurious falls, falls risk, participation, activity, leg strength, gait speed, balance, and falls efficacy. There was no significant difference in fall rate (intervention: 1.89 falls/person-year, control: 1.76 falls/person-year, incidence rate ratio=1.10, P=.74) or the proportion of fallers between the groups (risk ratio=.83, 95% confidence interval=.60-1.14). There was no significant difference in injurious fall rate (intervention: .74 injurious falls/person-year, control: .49 injurious falls/person-year, incidence rate ratio=1.57, P=.25), and there were no significant differences between groups on any other secondary outcome. This multifactorial falls prevention program was not effective in reducing falls in people with stroke who are at risk of falls nor was it more effective than usual care in improving gait, balance, and strength in people with stroke. Further research is required to identify effective interventions for this high-risk group. Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
Air pollution and mortality: A history
NASA Astrophysics Data System (ADS)
Anderson, H. R.
Mortality is the most important health effect of ambient air pollution and has been studied the longest. The earliest evidence relates to fog episodes but with the development of more precise methods of investigation it is still possible to discern short-term temporal associations with daily mortality at the historically low levels of air pollution that now exist in most developed countries. Another early observation was that mortality was higher in more polluted areas. This has been confirmed by modern cohort studies that account for other potential explanations for such associations. There does not appear to be a threshold of effect within the ambient range of concentrations. Advances in the understanding of air pollution and mortality have been driven by the combined development of methods and biomedical concepts. The most influential methodological developments have been in time-series techniques and the establishment of large cohort studies, both of which are underpinned by advances in data processing and statistical analysis. On the biomedical side two important developments can be identified. One has been the application of the concept of multifactorial disease causation to explaining how air pollution may affect mortality at low levels and why thresholds are not obvious at the population level. The other has been an increasing understanding of how air pollution may plausibly have pathophysiological effects that are remote from the lung interface with ambient air. Together, these advances have had a profound influence on policies to protect public health. Throughout the history of air pollution epidemiology, mortality studies have been central and this will continue because of the widespread availability of mortality data on a large population scale and the weight that mortality carries in estimating impacts for policy development.
Ali, Arif N; Switchenko, Jeffrey M; Kim, Sungjin; Kowalski, Jeanne; El-Deiry, Mark W; Beitler, Jonathan J
2014-11-15
The current study was conducted to develop a multifactorial statistical model to predict the specific head and neck (H&N) tumor site origin in cases of squamous cell carcinoma confined to the cervical lymph nodes ("unknown primaries"). The Surveillance, Epidemiology, and End Results (SEER) database was analyzed for patients with an H&N tumor site who were diagnosed between 2004 and 2011. The SEER patients were identified according to their H&N primary tumor site and clinically positive cervical lymph node levels at the time of presentation. The SEER patient data set was randomly divided into 2 data sets for the purposes of internal split-sample validation. The effects of cervical lymph node levels, age, race, and sex on H&N primary tumor site were examined using univariate and multivariate analyses. Multivariate logistic regression models and an associated set of nomograms were developed based on relevant factors to provide probabilities of tumor site origin. Analysis of the SEER database identified 20,011 patients with H&N disease with both site-level and lymph node-level data. Sex, race, age, and lymph node levels were associated with primary H&N tumor site (nasopharynx, hypopharynx, oropharynx, and larynx) in the multivariate models. Internal validation techniques affirmed the accuracy of these models on separate data. The incorporation of epidemiologic and lymph node data into a predictive model has the potential to provide valuable guidance to clinicians in the treatment of patients with squamous cell carcinoma confined to the cervical lymph nodes. © 2014 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society.
2013-01-01
Background Dental caries in children remains a significant public health problem. It is a disease with multifactorial causes. The aim of the study was to assess the prevalence and associated factors of dental caries among children between 7 to 14 years old. Methods A community based cross-sectional study was conducted in Gondar town from June 2011 to September 2011. A total of 842 children were involved in the study. Multi-stage sampling technique was used to select the children. Pretested and structured questionnaires were used to collect data from mothers. Clinical examination of children was done using dental caries criteria set by world health organization. Data were entered, cleaned and edited using EPI Info version 3.5.1 and exported to SPSS version 16.0 for analysis. Binary multiple logistic regression analyses was applied to test the association. Results Four hundred sixty three (55%) children were females. The prevalence of dental caries was 306(36.3%).The educational status of children’s father (AOR=0.3, 95%CI, 0.17, 0.80), monthly household income (AOR=0.59, 95%CI, 0.01, 0.45), regular teeth brushing (AOR=0.08, 95% CI, 0.03, 0.20) and using mouth rinsing (AOR=0.40, 95% CI, 0.2, 0.80) were found statistically significantly associated with dental caries. Conclusions Dental caries were high among children in Gondar town. Low socioeconomic status and poor oral hygiene practices were the influencing factors for dental caries. Oral hygiene, dietary habits and access to dental care services are supreme important for the prevention of the problem. PMID:23331467
McGuire, Jennifer A; Sherman, Paul M; Dean, Erica; Bernot, Jeremy M; Rowland, Laura M; McGuire, Stephen A; Kochunov, Peter V
2017-05-01
Repetitive hypobaric exposure in humans induces subcortical white matter change, observable on magnetic resonance imaging (MRI) and associated with cognitive impairment. Similar findings occur in traumatic brain injury (TBI). We are developing a swine MRI-driven model to understand the pathophysiology and to develop treatment interventions. Five miniature pigs (Sus scrofa domestica) were repetitively exposed to nonhypoxic hypobaria (30,000 feet/FIO 2 100%/transcutaneous PO 2 >90%) while under general anesthesia. Three pigs served as controls. Pre-exposure and postexposure MRIs were obtained that included structural sequences, dynamic contrast perfusion, and diffusion tensor quantification. Statistical comparison of individual subject and group change was performed utilizing a two-tailed t test. No structural imaging change was noted on T2-weighted or three-dimensional fluid-attenuated inversion recovery imaging between MRI 1 and MRI 2. No absolute difference in dynamic contrast perfusion was observed. A trend (p = 0.084) toward increase in interstitial extra-axonal fluid was noted. When individual subjects were examined, this trend toward increased extra-axonal fluid paralleled a decrease in contrast perfusion rate. This study demonstrates high reproducibility of quantitative noninvasive MRI, suggesting MRI is an appropriate assessment tool for TBI and hypobaric-induced injury research in swine. The lack of fluid-attenuated inversion recovery change may be multifactorial and requires further investigation. A trend toward increased extra-axonal water content that negatively correlates with dynamic contrast perfusion implies generalized axonal injury was induced. This study suggests this is a potential model for hypobaric-induced injury as well as potentially other axonal injuries such as TBI in which similar subcortical white matter change occurs. Further development of this model is necessary. Reprint & Copyright © 2017 Association of Military Surgeons of the U.S.
A novel interface for the telementoring of robotic surgery.
Shin, Daniel H; Dalag, Leonard; Azhar, Raed A; Santomauro, Michael; Satkunasivam, Raj; Metcalfe, Charles; Dunn, Matthew; Berger, Andre; Djaladat, Hooman; Nguyen, Mike; Desai, Mihir M; Aron, Monish; Gill, Inderbir S; Hung, Andrew J
2015-08-01
To prospectively evaluate the feasibility and safety of a novel, second-generation telementoring interface (Connect(™) ; Intuitive Surgical Inc., Sunnyvale, CA, USA) for the da Vinci robot. Robotic surgery trainees were mentored during portions of robot-assisted prostatectomy and renal surgery cases. Cases were assigned as traditional in-room mentoring or remote mentoring using Connect. While viewing two-dimensional, real-time video of the surgical field, remote mentors delivered verbal and visual counsel, using two-way audio and telestration (drawing) capabilities. Perioperative and technical data were recorded. Trainee robotic performance was rated using a validated assessment tool by both mentors and trainees. The mentoring interface was rated using a multi-factorial Likert-based survey. The Mann-Whitney and t-tests were used to determine statistical differences. We enrolled 55 mentored surgical cases (29 in-room, 26 remote). Perioperative variables of operative time and blood loss were similar between in-room and remote mentored cases. Robotic skills assessment showed no significant difference (P > 0.05). Mentors preferred remote over in-room telestration (P = 0.05); otherwise no significant difference existed in evaluation of the interfaces. Remote cases using wired (vs wireless) connections had lower latency and better data transfer (P = 0.005). Three of 18 (17%) wireless sessions were disrupted; one was converted to wired, one continued after restarting Connect, and the third was aborted. A bipolar injury to the colon occurred during one (3%) in-room mentored case; no intraoperative injuries were reported during remote sessions. In a tightly controlled environment, the Connect interface allows trainee robotic surgeons to be telementored in a safe and effective manner while performing basic surgical techniques. Significant steps remain prior to widespread use of this technology. © 2014 The Authors BJU International © 2014 BJU International Published by John Wiley & Sons Ltd.
Characterization of nanosecond pulse electrical field shock waves using imaging techniques
NASA Astrophysics Data System (ADS)
Mimun, L. Chris; Ibey, Bennett L.; Roth, Caleb C.; Barnes, Ronald A.; Sardar, Dhiraj K.; Beier, Hope T.
2015-03-01
Nanosecond pulsed electric fields (nsPEF) cause the formation of small pores, termed nanopores, in the membrane of cells. Current nanoporation models treat nsPEF exposure as a purely electromagnetic phenomenon, but recent publications showing pressure transients, ROS production, temperature gradients, and pH waves suggest the stimulus may be physically and chemically multifactorial causing elicitation of diverse biological conditions and stressors. Our research group's goal is to quantify the breadth and participation of these stressors generated during nsPEF exposure and determine their relative importance to the observed cellular response. In this paper, we used advanced imaging techniques to identify a possible source of nsPEF-induced acoustic shock waves. nsPEFs were delivered in an aqueous media via a pair of 125 μm tungsten electrodes separated by 100 μm, mirroring our previously published cellular exposure experiments. To visualize any pressure transients emanating from the electrodes or surrounding medium, we used the Schlieren imaging technique. Resulting images and measurements confirmed that mechanical pressure waves and electrode-based stresses are formed during nsPEF, resulting in a clearer understanding of the whole exposure dosimetry. This information will be used to better quantify the impact of nsPEF-induced acoustic shock waves on cells, and has provided further evidence of non-electrical-field induced exposures for elicitation of bioieffects.
Taamalli, Amani; Arráez-Román, David; Barrajón-Catalán, Enrique; Ruiz-Torres, Verónica; Pérez-Sánchez, Almudena; Herrero, Miguel; Ibañez, Elena; Micol, Vicente; Zarrouk, Mokhtar; Segura-Carretero, Antonio; Fernández-Gutiérrez, Alberto
2012-06-01
A comparison among different advanced extraction techniques such as microwave-assisted extraction (MAE), supercritical fluid extraction (SFE) and pressurized liquid extraction (PLE), together with traditional solid-liquid extraction, was performed to test their efficiency towards the extraction of phenolic compounds from leaves of six Tunisian olive varieties. Extractions were carried out at the best selected conditions for each technique; the obtained extracts were chemically characterized using high-performance liquid chromatography (HPLC) coupled to electrospray time-of-flight mass spectrometry (ESI-TOF-MS) and electrospray ion trap tandem mass spectrometry (ESI-IT-MS(2)). As expected, higher extraction yields were obtained for PLE while phenolic profiles were mainly influenced by the solvent used as optimum in the different extraction methods. A larger number of phenolic compounds, mostly of a polar character, were found in the extracts obtained by using MAE. Best extraction yields do not correlate with highest cytotoxic activity against breast cancer cells, indicating that cytotoxicity is highly dependent on the presence of certain compounds in the extracts, although not exclusively on a single compound. Therefore, a multifactorial behavior is proposed for the anticancer activity of olive leaf compounds. Copyright © 2012 Elsevier Ltd. All rights reserved.
Single nucleotide polymorphisms associated with nonsyndromic cryptorchidism in Mexican patients.
Chávez-Saldaña, M; Vigueras-Villaseñor, R M; Yokoyama-Rebollar, E; Landero-Huerta, D A; Rojas-Castañeda, J C; Taja-Chayeb, L; Cuevas-Alpuche, J O; Zambrano, E
2018-02-01
Cryptorchidism is a frequent genitourinary malformation considered as an important risk factor for infertility and testicular malignancy. The aetiology of cryptorchidism is multifactorial in which certain SNPs, capable of inhibiting the development of the gubernaculum, are implicated. We analysed 16 SNPs by allelic discrimination and automated sequencing in 85 patients and 99 healthy people, with the objective to identify the association between these variants and isolated cryptorchidism. In two different patients with unilateral cryptorchidism, we found the variants rs121912556 and p.R105R of INSL3 gene in a heterozygous form associated with cryptorchidism, so we could considered them as risk factors for cryptorchidism. On the other hand, SNPs rs10421916 of INSL3 gene, as well as the variants rs1555633 and rs7325513 in the RXFP2 gene, and rs3779456 variant of the HOXA10 gene were statistically significant, when the patients and controls were compared and could be considered as protective factors since are predominantly present in controls. The genotype-phenotype correlation did not show statistical significance. With these results, we could conclude that these polymorphisms can be considered as important variants in our population and would contribute in the future knowledge of the aetiology and physiopathology of cryptorchidism. © 2017 Blackwell Verlag GmbH.
Kouris, Anargyros; Armyra, Kalliopi; Christodoulou, Christos; Katoulis, Alexandros; Potouridou, Irene; Tsatovidou, Revekka; Rigopoulos, Dimitrios; Kontochristopoulos, Georgios
2015-06-01
Chronic hand eczema is a common dermatological disorder of multifactorial aetiology. It affects physical, material, social and psychological aspects of life, thereby impairing health-related quality of life. The aim of the present study was to assess quality of life, anxiety, depression and obsessive-compulsive tendencies in patients with chronic hand eczema. Seventy-one patients with chronic hand eczema were included in the study. Quality of life was evaluated according to the Dermatology Life Quality Index (DLQI). Patients were also assessed for anxiety and depression with the Hospital Anxiety and Depression Scale (HADS), and for compulsive behaviour with the Leyton Trait Scale. The DLQI score was 11.11 ± 1.81 in patients with chronic hand eczema. Scores on the Leyton Trait Scale were significantly higher than those of healthy controls (p < 0.027). As concerns the HADS-Anxiety subscale, patients with hand dermatitis had statistically significantly higher scores than those of volunteers (p = 0.002). In contrast, no statistically significant difference was found between the two groups with regard to the HADS-Depression subscale score and total HADS score. Hand eczema treatment should address the severity of skin lesions as well as the psychological impact of hand eczema. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Villa-Uriol, M. C.; Berti, G.; Hose, D. R.; Marzo, A.; Chiarini, A.; Penrose, J.; Pozo, J.; Schmidt, J. G.; Singh, P.; Lycett, R.; Larrabide, I.; Frangi, A. F.
2011-01-01
Cerebral aneurysms are a multi-factorial disease with severe consequences. A core part of the European project @neurIST was the physical characterization of aneurysms to find candidate risk factors associated with aneurysm rupture. The project investigated measures based on morphological, haemodynamic and aneurysm wall structure analyses for more than 300 cases of ruptured and unruptured aneurysms, extracting descriptors suitable for statistical studies. This paper deals with the unique challenges associated with this task, and the implemented solutions. The consistency of results required by the subsequent statistical analyses, given the heterogeneous image data sources and multiple human operators, was met by a highly automated toolchain combined with training. A testimonial of the successful automation is the positive evaluation of the toolchain by over 260 clinicians during various hands-on workshops. The specification of the analyses required thorough investigations of modelling and processing choices, discussed in a detailed analysis protocol. Finally, an abstract data model governing the management of the simulation-related data provides a framework for data provenance and supports future use of data and toolchain. This is achieved by enabling the easy modification of the modelling approaches and solution details through abstract problem descriptions, removing the need of repetition of manual processing work. PMID:22670202
Routine Discovery of Complex Genetic Models using Genetic Algorithms
Moore, Jason H.; Hahn, Lance W.; Ritchie, Marylyn D.; Thornton, Tricia A.; White, Bill C.
2010-01-01
Simulation studies are useful in various disciplines for a number of reasons including the development and evaluation of new computational and statistical methods. This is particularly true in human genetics and genetic epidemiology where new analytical methods are needed for the detection and characterization of disease susceptibility genes whose effects are complex, nonlinear, and partially or solely dependent on the effects of other genes (i.e. epistasis or gene-gene interaction). Despite this need, the development of complex genetic models that can be used to simulate data is not always intuitive. In fact, only a few such models have been published. We have previously developed a genetic algorithm approach to discovering complex genetic models in which two single nucleotide polymorphisms (SNPs) influence disease risk solely through nonlinear interactions. In this paper, we extend this approach for the discovery of high-order epistasis models involving three to five SNPs. We demonstrate that the genetic algorithm is capable of routinely discovering interesting high-order epistasis models in which each SNP influences risk of disease only through interactions with the other SNPs in the model. This study opens the door for routine simulation of complex gene-gene interactions among SNPs for the development and evaluation of new statistical and computational approaches for identifying common, complex multifactorial disease susceptibility genes. PMID:20948983
Naeem, Naghma; Muijtjens, Arno
2015-04-01
The psychological construct of emotional intelligence (EI), its theoretical models, measurement instruments and applications have been the subject of several research studies in health professions education. The objective of the current study was to investigate the factorial validity and reliability of a bilingual version of the Schutte Self Report Emotional Intelligence Scale (SSREIS) in an undergraduate Arab medical student population. The study was conducted during April-May 2012. A cross-sectional survey design was employed. A sample (n = 467) was obtained from undergraduate medical students belonging to the male and female medical college of King Saud University, Riyadh, Saudi Arabia. Exploratory and confirmatory factor analysis was performed using SPSS 16.0 and AMOS 4.0 statistical software to determine the factor structure. Reliability was determined using Cronbach's alpha statistics. The results obtained using an undergraduate Arab medical student sample supported a multidimensional; three factor structure of the SSREIS. The three factors are Optimism, Awareness-of-Emotions and Use-of-Emotions. The reliability (Cronbach's alpha) for the three subscales was 0.76, 0.72 and 0.55, respectively. Emotional intelligence is a multifactorial construct (three factors). The bilingual version of the SSREIS is a valid and reliable measure of trait emotional intelligence in an undergraduate Arab medical student population.
Complex Adaptive System Models and the Genetic Analysis of Plasma HDL-Cholesterol Concentration
Rea, Thomas J.; Brown, Christine M.; Sing, Charles F.
2006-01-01
Despite remarkable advances in diagnosis and therapy, ischemic heart disease (IHD) remains a leading cause of morbidity and mortality in industrialized countries. Recent efforts to estimate the influence of genetic variation on IHD risk have focused on predicting individual plasma high-density lipoprotein cholesterol (HDL-C) concentration. Plasma HDL-C concentration (mg/dl), a quantitative risk factor for IHD, has a complex multifactorial etiology that involves the actions of many genes. Single gene variations may be necessary but are not individually sufficient to predict a statistically significant increase in risk of disease. The complexity of phenotype-genotype-environment relationships involved in determining plasma HDL-C concentration has challenged commonly held assumptions about genetic causation and has led to the question of which combination of variations, in which subset of genes, in which environmental strata of a particular population significantly improves our ability to predict high or low risk phenotypes. We document the limitations of inferences from genetic research based on commonly accepted biological models, consider how evidence for real-world dynamical interactions between HDL-C determinants challenges the simplifying assumptions implicit in traditional linear statistical genetic models, and conclude by considering research options for evaluating the utility of genetic information in predicting traits with complex etiologies. PMID:17146134
Saddu, Shweta Channavir; Dyasanoor, Sujatha; Valappila, Nidhin J; Ravi, Beena Varma
2015-08-01
Temporomandibular disorders (TMD) are the most common non-dental cause of orofacial pain with a multifactorial aetiology. To evaluate the head and craniocervical posture between individuals with and without TMD and its sub types by photographic and radiographic method. Thirty four TMD patients diagnosed according to Research Diagnostic Criteria for TMD's (RDC/TMD) and were divided into 2 groups: Group I (muscle disorder), Group II (disc displacement). Control group comprised of 34 age and sex matched subjects without TMD. Lateral view photographs were taken and the head posture angle was measured. Craniocervical posture was assessed on lateral skull radiograph with two angles (Craniocervical Angle, Cervical Curvature Angle) and two distances (Suboccipital Space, Atlas-Axis Distance). To compare the results, t-test was used with significance level of 0.05. Head posture showed no statistical significant difference (p > 0.05) between Group I, II and control group in both photographic and radiographic methods. The cervical curvature angle showed significant difference (p = 0.045) in Group I only. Atlas-Axis Distance was statistically significant in Group II (p = 0.001). The present study confirmed that there is a negative association of head posture and TMD whereas, cervical lordosis was present in Group I only.
Saddu, Shweta Channavir; Dyasanoor, Sujatha; Ravi, Beena Varma
2015-01-01
Introduction Temporomandibular disorders (TMD) are the most common non-dental cause of orofacial pain with a multifactorial aetiology. Aim To evaluate the head and craniocervical posture between individuals with and without TMD and its sub types by photographic and radiographic method. Materials and Methods Thirty four TMD patients diagnosed according to Research Diagnostic Criteria for TMD’s (RDC/TMD) and were divided into 2 groups: Group I (muscle disorder), Group II (disc displacement). Control group comprised of 34 age and sex matched subjects without TMD. Lateral view photographs were taken and the head posture angle was measured. Craniocervical posture was assessed on lateral skull radiograph with two angles (Craniocervical Angle, Cervical Curvature Angle) and two distances (Suboccipital Space, Atlas-Axis Distance). To compare the results, t-test was used with significance level of 0.05. Results Head posture showed no statistical significant difference (p > 0.05) between Group I, II and control group in both photographic and radiographic methods. The cervical curvature angle showed significant difference (p = 0.045) in Group I only. Atlas-Axis Distance was statistically significant in Group II (p = 0.001). Conclusion The present study confirmed that there is a negative association of head posture and TMD whereas, cervical lordosis was present in Group I only. PMID:26436048
Understanding alcohol use disorders with neuroelectrophysiology
RANGASWAMY, MADHAVI; PORJESZ, BERNICE
2015-01-01
Neurocognitive deficits associated with impairments in various brain regions and neural circuitries, particularly involving frontal lobes, have been associated with chronic alcoholism, as well as with a predisposition to develop alcohol use and related disorders (AUDs). AUD is a multifactorial disorder caused by complex interactions between behavioral, genetic, and environmental liabilities. Neuroelectrophysiological techniques are instrumental in understanding brain and behavior relationships and have also proved very useful in evaluating the genetic diathesis of alcoholism. This chapter describes findings from neuroelectrophysiological measures (electroencephalogram, event-related potentials, and event-related oscillations) related to acute and chronic effects of alcohol on the brain and those that reflect underlying deficits related to a predisposition to develop AUDs and related disorders. The utility of these measures as effective endophenotypes to identify and understand genes associated with brain electrophysiology, cognitive networks, and AUDs has also been discussed. PMID:25307587
PVCM, PVCD, EPL, and irritable larynx syndrome: what are we talking about and how do we treat it?
Andrianopoulos, M V; Gallivan, G J; Gallivan, K H
2000-12-01
Paroxysmal vocal cord movement/motion (PVCM), paroxysmal vocal cord dysfunction (PVCD), episodic paroxysmal laryngospasm (EPL), and irritable larynx syndrome (ILS) are terms used to describe laryngeal dysfunction masquerading as asthma, upper airway obstruction, or functional and organic voice disorders. The differential diagnosis of PVCM, PVCD, EPL, and ILS is critical to successful medical and behavioral management of the patient. During the past 10 years, 27 subjects, ages 15-79 years, were identified to have paroxysms of inspiratory stridor, acute respiratory distress, associated aphonia and dysphonia, resulting in misdiagnosis and unnecessary emergency treatments, including endotracheal intubation, cardiopulmonary resuscitation, massive pharmacotherapy, or tracheostomy. A multifactorial management program is proposed utilizing principles of motor learning, neurolinguistic programming model, respiratory and phonatory synchronization, relaxation techniques, concurrent monitoring of behavioral adjustments, and formal psychological counseling.
New frontiers in the neuroscience of the sense of agency
David, Nicole
2012-01-01
The sense that I am the author of my own actions, including the ability to distinguish my own from other people's actions, is a fundamental building block of our sense of self, on the one hand, and successful social interactions, on the other. Using cognitive neuroscience techniques, researchers have attempted to elucidate the functional basis of this intriguing phenomenon, also trying to explain pathological abnormalities of action awareness in certain psychiatric and neurological disturbances. Recent conceptual, technological, and methodological advances suggest several interesting and necessary new leads for future research on the neuroscience of agency. Here I will describe new frontiers for the field such as the need for novel and multifactorial paradigms, anatomically plausible network models for the sense of agency, investigations of the temporal dynamics during agentic processing and ecologically valid virtual reality (VR) applications. PMID:22670145
Comparative Analysis Between Computed and Conventional Inferior Alveolar Nerve Block Techniques.
Araújo, Gabriela Madeira; Barbalho, Jimmy Charles Melo; Dias, Tasiana Guedes de Souza; Santos, Thiago de Santana; Vasconcellos, Ricardo José de Holanda; de Morais, Hécio Henrique Araújo
2015-11-01
The aim of this randomized, double-blind, controlled trial was to compare the computed and conventional inferior alveolar nerve block techniques in symmetrically positioned inferior third molars. Both computed and conventional anesthetic techniques were performed in 29 healthy patients (58 surgeries) aged between 18 and 40 years. The anesthetic of choice was 2% lidocaine with 1: 200,000 epinephrine. The Visual Analogue Scale assessed the pain variable after anesthetic infiltration. Patient satisfaction was evaluated using the Likert Scale. Heart and respiratory rates, mean time to perform technique, and the need for additional anesthesia were also evaluated. Pain variable means were higher for the conventional technique as compared with computed, 3.45 ± 2.73 and 2.86 ± 1.96, respectively, but no statistically significant differences were found (P > 0.05). Patient satisfaction showed no statistically significant differences. The average computed technique runtime and the conventional were 3.85 and 1.61 minutes, respectively, showing statistically significant differences (P <0.001). The computed anesthetic technique showed lower mean pain perception, but did not show statistically significant differences when contrasted to the conventional technique.
Besseris, George J
2013-01-01
Data screening is an indispensable phase in initiating the scientific discovery process. Fractional factorial designs offer quick and economical options for engineering highly-dense structured datasets. Maximum information content is harvested when a selected fractional factorial scheme is driven to saturation while data gathering is suppressed to no replication. A novel multi-factorial profiler is presented that allows screening of saturated-unreplicated designs by decomposing the examined response to its constituent contributions. Partial effects are sliced off systematically from the investigated response to form individual contrasts using simple robust measures. By isolating each time the disturbance attributed solely to a single controlling factor, the Wilcoxon-Mann-Whitney rank stochastics are employed to assign significance. We demonstrate that the proposed profiler possesses its own self-checking mechanism for detecting a potential influence due to fluctuations attributed to the remaining unexplainable error. Main benefits of the method are: 1) easy to grasp, 2) well-explained test-power properties, 3) distribution-free, 4) sparsity-free, 5) calibration-free, 6) simulation-free, 7) easy to implement, and 8) expanded usability to any type and size of multi-factorial screening designs. The method is elucidated with a benchmarked profiling effort for a water filtration process.
A Distribution-Free Multi-Factorial Profiler for Harvesting Information from High-Density Screenings
Besseris, George J.
2013-01-01
Data screening is an indispensable phase in initiating the scientific discovery process. Fractional factorial designs offer quick and economical options for engineering highly-dense structured datasets. Maximum information content is harvested when a selected fractional factorial scheme is driven to saturation while data gathering is suppressed to no replication. A novel multi-factorial profiler is presented that allows screening of saturated-unreplicated designs by decomposing the examined response to its constituent contributions. Partial effects are sliced off systematically from the investigated response to form individual contrasts using simple robust measures. By isolating each time the disturbance attributed solely to a single controlling factor, the Wilcoxon-Mann-Whitney rank stochastics are employed to assign significance. We demonstrate that the proposed profiler possesses its own self-checking mechanism for detecting a potential influence due to fluctuations attributed to the remaining unexplainable error. Main benefits of the method are: 1) easy to grasp, 2) well-explained test-power properties, 3) distribution-free, 4) sparsity-free, 5) calibration-free, 6) simulation-free, 7) easy to implement, and 8) expanded usability to any type and size of multi-factorial screening designs. The method is elucidated with a benchmarked profiling effort for a water filtration process. PMID:24009744
Effect assessment in work environment interventions: a methodological reflection.
Neumann, W P; Eklund, J; Hansson, B; Lindbeck, L
2010-01-01
This paper addresses a number of issues for work environment intervention (WEI) researchers in light of the mixed results reported in the literature. If researchers emphasise study quality over intervention quality, reviews that exclude case studies with high quality and multifactorial interventions may be vulnerable to 'quality criteria selection bias'. Learning from 'failed' interventions is inhibited by both publication bias and reporting lengths that limit information on relevant contextual and implementation factors. The authors argue for the need to develop evaluation approaches consistent with the complexity of multifactorial WEIs that: a) are owned by and aimed at the whole organisation; and b) include intervention in early design stages where potential impact is highest. Context variety, complexity and instability in and around organisations suggest that attention might usefully shift from generalisable 'proof of effectiveness' to a more nuanced identification of intervention elements and the situations in which they are more likely to work as intended. STATEMENT OF RELEVANCE: This paper considers ergonomics interventions from perspectives of what constitutes quality and 'proof". It points to limitations of traditional experimental intervention designs and argues that the complexity of organisational change, and the need for multifactorial interventions that reach deep into work processes for greater impact, should be recognised.
Epstein, Murray; de Marchena, Eduardo
2015-02-01
Resistant hypertension is a common medical problem that is increasing with the advent of an increasingly older and heavier population. The etiology of resistant hypertension is almost always multifactorial, but the results of numerous studies indicate that renal sympathetic activation is a particularly common cause of resistance to antihypertensive treatment. Consistent with the belief in a pivotal role of renal sympathetic stimulation, there has been a growing interest in renal denervation (RDN) treatment strategies. The long-awaited results of SYMPLICITY HTN-3 study disclosed that the reduction in blood pressure by the SYMPLICITY device did not differ from that in the sham-procedure arm of the study. In the present article, we identify several factors that explain why the study failed to demonstrate any benefit from the intervention. The reasons are multifactorial and include inadequate screening at entry and frequent medication changes during the study. Additional problems include the lack of experience of many operators with the SYMPLICITY device and procedure variability, as attested to by a diminished number of ablation "quadrants." Also a factor was the inability of the first generation Medtronic device to allow four ablations to be performed simultaneously. We recommend that future RDN studies adhere to more rigorous screening procedures, and utilize newer multi-site denervation systems that facilitate four ablations simultaneously. Drug optimization should be achieved by monitoring adherence throughout the study. Nevertheless, we are optimistic about a future role of RDN. To optimize chances of success, increased efforts are necessary to identify the appropriate patients for RDN and investigators must use second and third generation denervation devices and techniques. Copyright © 2015 American Society of Hypertension. Published by Elsevier Inc. All rights reserved.
Descriptive Statistical Techniques for Librarians. 2nd Edition.
ERIC Educational Resources Information Center
Hafner, Arthur W.
A thorough understanding of the uses and applications of statistical techniques is integral in gaining support for library funding or new initiatives. This resource is designed to help practitioners develop and manipulate descriptive statistical information in evaluating library services, tracking and controlling limited resources, and analyzing…
ERIC Educational Resources Information Center
Williams, Immanuel James; Williams, Kelley Kim
2016-01-01
Understanding summary statistics and graphical techniques are building blocks to comprehending concepts beyond basic statistics. It's known that motivated students perform better in school. Using examples that students find engaging allows them to understand the concepts at a deeper level.
Cabrera-Díaz, E; Martínez-Chávez, L; Sánchez-Camarena, J; Muñiz-Flores, J A; Castillo, A; Gutiérrez-González, P; Arvizu-Medrano, S M; González-Aguilar, D G; Martínez-Gonzáles, N E
2018-08-01
Simultaneous and individual enumeration of Salmonella, Shigella and Listeria monocytogenes was compared on inoculated Roma tomatoes and Serrano peppers using an Most Probable Number (MPN) technique. Samples consisting of tomatoes (4 units) or peppers (8 units) were individually inoculated with a cocktail of three strains of Salmonella, Shigella or L. monocytogenes, or by simultaneous inoculation of three strains of each pathogen, at low (1.2-1.7 log CFU/sample) and high (2.2-2.7 log CFU/sample) inocula. Samples were analyzed by an MPN technique using universal pre-enrichment (UP) broth at 35 °C for 24 ± 2 h. The UP tubes from each MPN series were transferred to enrichment and plating media following adequate conventional methods for isolating each pathogen. Data were analyzed using multifactorial analysis of variance (p < 0.05) and LSD multiple rang test. There were differences (p < 0.05) in recovery of simultaneous and individual bacteria inoculated (individual > simultaneous), type of bacteria (Salmonella > Shigella and L. monocytogenes), type of sample (UP broth > pepper and tomato), and inoculum level (high > low). The MPN technique was effective for Salmonella on both commodities. Shigella counts were higher on tomatoes compared to peppers, (p < 0.05), and for L. monocytogenes on peppers (p < 0.05). Copyright © 2018 Elsevier Ltd. All rights reserved.
Chi-squared and C statistic minimization for low count per bin data
NASA Astrophysics Data System (ADS)
Nousek, John A.; Shue, David R.
1989-07-01
Results are presented from a computer simulation comparing two statistical fitting techniques on data samples with large and small counts per bin; the results are then related specifically to X-ray astronomy. The Marquardt and Powell minimization techniques are compared by using both to minimize the chi-squared statistic. In addition, Cash's C statistic is applied, with Powell's method, and it is shown that the C statistic produces better fits in the low-count regime than chi-squared.
Chi-squared and C statistic minimization for low count per bin data. [sampling in X ray astronomy
NASA Technical Reports Server (NTRS)
Nousek, John A.; Shue, David R.
1989-01-01
Results are presented from a computer simulation comparing two statistical fitting techniques on data samples with large and small counts per bin; the results are then related specifically to X-ray astronomy. The Marquardt and Powell minimization techniques are compared by using both to minimize the chi-squared statistic. In addition, Cash's C statistic is applied, with Powell's method, and it is shown that the C statistic produces better fits in the low-count regime than chi-squared.
EVALUATION OF THE RELATIONSHIP BETWEEN ANDROGENETIC ALOPECIA AND DEMODEX INFESTATION
Zari, Javidi; Abdolmajid, Fata; Masood, Maleki; Vahid, Mashayekhi; Yalda, Nahidi
2008-01-01
Introduction: Androgenetic alopecia (AGA) is one of the most common dermatologic disorders with a multifactorial etiology. Inflammatory activators such as Demodex infestation may play a role in the pathogenesis of some cases of androgenetic alopecia that do not respond to common treatments such as minoxidil and finasteride. The goal of this study is to evaluate the relationship between Demodex infestation and AGA. Materials and Methods: In this case-control study, 41 patients with AGA referred to the Dermatology Clinic of Imam Reza Hospital and 33 healthy individuals were evaluated as control. All of them were between 20 and 40 years old men. In order to identify Demodex infestation they were referred to the Parasitology laboratory. Results: Demodex was detected in 19.5% of patients and 15.2% of controls; therefore, there was no significant relationship between them statistically (P = 0.0787). Most of patients (85.4%) had greasy hair. The most common pattern of baldness was II degree in Hamilton scale. Conclusion: There is no relation between AGA and Demodex. PMID:19881989
Causes and consequences of anterior pharyngeal pouch after total laryngectomy.
Anderson, S; Hogan, D; Panizza, B
2014-07-01
To assess the frequency of anterior pharyngeal pouch formation after total laryngectomy, and to discuss the causes and consequences of anterior pharyngeal pouch formation. A prospective, observational study of 43 patients undergoing total laryngectomy. Data collected included laryngeal defect closure type, tumour staging and demographic information. A barium swallow was performed on day 7-14 after surgery to assess for anterior pharyngeal pouch formation and fistula formation. The incidence of anterior pharyngeal pouch formation was 47 per cent. Patients who did not have an anterior pharyngeal pouch on swallow imaging assessment were less likely to develop a pharyngo-cutaneous fistula. There was no statistically significant association between laryngeal defect closure type and anterior pharyngeal pouch formation. The anterior pharyngeal pouch is a dynamic phenomenon best investigated with a fluoroscopic swallow imaging study. Its causes are multi-factorial. Absence of an anterior pharyngeal pouch appears to confer protection against pharyngo-cutaneous fistula formation, hastening commencement of adjuvant therapy and an oral diet.
Machine Learning for Detecting Gene-Gene Interactions
McKinney, Brett A.; Reif, David M.; Ritchie, Marylyn D.; Moore, Jason H.
2011-01-01
Complex interactions among genes and environmental factors are known to play a role in common human disease aetiology. There is a growing body of evidence to suggest that complex interactions are ‘the norm’ and, rather than amounting to a small perturbation to classical Mendelian genetics, interactions may be the predominant effect. Traditional statistical methods are not well suited for detecting such interactions, especially when the data are high dimensional (many attributes or independent variables) or when interactions occur between more than two polymorphisms. In this review, we discuss machine-learning models and algorithms for identifying and characterising susceptibility genes in common, complex, multifactorial human diseases. We focus on the following machine-learning methods that have been used to detect gene-gene interactions: neural networks, cellular automata, random forests, and multifactor dimensionality reduction. We conclude with some ideas about how these methods and others can be integrated into a comprehensive and flexible framework for data mining and knowledge discovery in human genetics. PMID:16722772
Cestari, Andrea
2013-01-01
Predictive modeling is emerging as an important knowledge-based technology in healthcare. The interest in the use of predictive modeling reflects advances on different fronts such as the availability of health information from increasingly complex databases and electronic health records, a better understanding of causal or statistical predictors of health, disease processes and multifactorial models of ill-health and developments in nonlinear computer models using artificial intelligence or neural networks. These new computer-based forms of modeling are increasingly able to establish technical credibility in clinical contexts. The current state of knowledge is still quite young in understanding the likely future direction of how this so-called 'machine intelligence' will evolve and therefore how current relatively sophisticated predictive models will evolve in response to improvements in technology, which is advancing along a wide front. Predictive models in urology are gaining progressive popularity not only for academic and scientific purposes but also into the clinical practice with the introduction of several nomograms dealing with the main fields of onco-urology.
Bansal, Mohit; Singh, Sunint; Bector, Aditi; Dogra, Mrigank
2018-01-01
The objective of the study was to obtain data on prevalence and severity of dental erosion among acid industry workers in Baddi (Himachal Pradesh). A cross-sectional study was conducted among 800 battery industry workers. The demographic details were recorded on a prestructured pro forma. Type III examination was done. Dental erosion was recorded based on the index given by Bardsley (simplified scoring criteria for tooth wear index). Appropriate statistical tests were used to interpret the data. The prevalence of dental erosion was found to be 48.6%. Prevalence increased with the duration of employment. Dental erosion was most commonly found in the labial surfaces of maxillary anterior teeth. Erosion is a condition which is multifactorial and becomes more aggravating in the presence of acidic environment. Therefore, the workers working in such conditions should be more careful, and mandatory policies should also be followed by such industries to maintain the overall health of the workers.
Multifactorial analysis of factors affecting recurrence of stroke in Japan.
Omori, Toyonori; Kawagoe, Masahiro; Moriyama, Michiko; Yasuda, Takeshi; Ito, Yasuhiro; Hyakuta, Takeshi; Nagatsuka, Kazuyuki; Matsumoto, Masayasu
2015-03-01
Data on factors affecting stroke recurrence are relatively limited. The authors examined potential factors affecting stroke recurrence, retrospectively. The study participants were 1087 patients who were admitted to stroke centers suffering from first-ever ischemic stroke and returned questionnaires with usable information after discharge. The authors analyzed the association between clinical parameters of the patients and their prognosis. Recurrence rate of during an average of 2 years after discharge was 21.3%, and there were differences among stroke subtypes. It was found that the disability level of the patients after discharge correlated well with the level at discharge (r s = 0.66). Multivariate logistic regression analysis of the data shows that modified Rankin Scale score, National Institute of Health Stroke Scale score, gender, age, and family history had statistically significant impacts on stroke recurrence, and the impact was different depending on subtypes. These findings suggest that aggressive and persistent health education for poststroke patients and management of risk factors are essential to reduce stroke recurrence. © 2012 APJPH.
Three lessons for genetic toxicology from baseball analytics.
Dertinger, Stephen D
2017-07-01
In many respects the evolution of baseball statistics mirrors advances made in the field of genetic toxicology. From its inception, baseball and statistics have been inextricably linked. Generations of players and fans have used a number of relatively simple measurements to describe team and individual player's current performance, as well as for historical record-keeping purposes. Over the years, baseball analytics has progressed in several important ways. Early advances were based on deriving more meaningful metrics from simpler forerunners. Now, technological innovations are delivering much deeper insights. Videography, radar, and other advances that include automatic player recognition capabilities provide the means to measure more complex and useful factors. Fielders' reaction times, efficiency of the route taken to reach a batted ball, and pitch-framing effectiveness come to mind. With the current availability of complex measurements from multiple data streams, multifactorial analyses occurring via machine learning algorithms have become necessary to make sense of the terabytes of data that are now being captured in every Major League Baseball game. Collectively, these advances have transformed baseball statistics from being largely descriptive in nature to serving data-driven, predictive roles. Whereas genetic toxicology has charted a somewhat parallel course, a case can be made that greater utilization of baseball's mindset and strategies would serve our scientific field well. This paper describes three useful lessons for genetic toxicology, courtesy of the field of baseball analytics: seek objective knowledge; incorporate multiple data streams; and embrace machine learning. Environ. Mol. Mutagen. 58:390-397, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
Horák, Stanislav; Sovová, Eliška; Pastucha, Dalibor; Konečný, Petr; Radová, Lenka; Calabová, Naděžda; Janoutová, Jana; Janout, Vladimír
2017-12-01
Obesity is a multifactorial disease. This non-infectious epidemic has reached pandemic proportions in the 21 century. Posture is a dynamic process referring to an active maintenance of body movement segments against the action of external forces. The aim of the study was to investigate the effect of comprehensive group therapy for obese persons on selected anthropometric and postural parameters. The study comprised 53 females with a mean age of 44.5 years (range 29–65 years, standard deviation 9.42 years, median 44 years), who completed a controlled weight loss programme. At the beginning and at the end of the programme, anthropometric parameters (Body Mass Index (BMI), weight and waist circumference) were measured and the posturography tests Limits of Stability (LOS) and Motor Control Test (MCT) were performed using the NeuroCom's SMART EquiTest system. The data were statistically analyzed using R software at a level of significance of 0.05. There were positive changes after the controlled weight loss programme in anthropometric parameters (BMI reduction, with p<0.001; waist circumference reduction, with p<0.001; and weight loss, with p<0.001), postural stability with statistically significant (p<0.05) improvements in both postural activity (LOS test parameters) and reactions (MCT parameters). The study showed a statistically significant effect of comprehensive group therapy for obesity in terms of reductions in waist circumference, body weight and BMI, and thus the overall reduction of both cardiovascular and metabolic risks, as well as improved postural skills (activity and reactions). Copyright© by the National Institute of Public Health, Prague 2017
Factors affecting low back pain in adolescents.
Korovessis, Panagiotis; Repantis, Thomas; Baikousis, Andreas
2010-12-01
Prospective multifactorial study on low back pain (LBP) in adolescents. Most studies on LBP have focused on adults although many investigations have shown that the roots of LBP lie in adolescence. Several mechanical, physical, and behavioral factors have been associated with nonspecific LBP in adolescents. To investigate the effect of all previously reported parameters together with psychological and psychosocial factors using advanced statistics, on LBP in adolescents aged 15 to 19 years. Six hundred and eighty-eight students aged 16±1 years from 5 randomly selected high schools participated in this study and completed a questionnaire containing questions on daily activity, backpack carrying, psychological and psychosocial behavior. Anthropometric data as well as biplane spinal curvatures together with questionnaire results were included in the analysis using advanced statistics. LBP reported 41% of the participants. Generally, statistically significant correlations were found between LBP (0.002), physical activity (P<0.001), physician consultation (P=0.024), and depression (P<0.001). Sex-related differences were shown regarding LBP intensity (P=0.005) and frequency (P=0.013), stress (P<0.03), depression (P=0.005), and nervous mood (P=0.036) in favor of male students. Male adolescents had continuous energy (P=0.0258) and were calm (P=0.029) in contrast with female counterparts. LBP was sex-related and was less common in adolescents with frequent activity. Adolescent girls with stress, depressive mood, and low energy have more LBP than boys, which makes physician consultation for LBP more common in female adolescents. Systematic physical activity and control of psychological profile should decrease LBP frequency and intensity.
The Importance of Introductory Statistics Students Understanding Appropriate Sampling Techniques
ERIC Educational Resources Information Center
Menil, Violeta C.
2005-01-01
In this paper the author discusses the meaning of sampling, the reasons for sampling, the Central Limit Theorem, and the different techniques of sampling. Practical and relevant examples are given to make the appropriate sampling techniques understandable to students of Introductory Statistics courses. With a thorough knowledge of sampling…
Wang, Xiaoyan; Laubenbacher, Reinhard C.
2017-01-01
Background Investigations into the factors behind coauthorship growth in biomedical research have mostly focused on specific disciplines or journals, and have rarely controlled for factors in combination or considered changes in their effects over time. Observers often attribute the growth to the increasing complexity or competition (or both) of research practices, but few attempts have been made to parse the contributions of these two likely causes. Objectives We aimed to assess the effects of complexity and competition on the incidence and growth of coauthorship, using a sample of the biomedical literature spanning multiple journals and disciplines. Methods Article-level bibliographic data from PubMed were combined with publicly available bibliometric data from Web of Science and SCImago over the years 1999–2007. We selected four predictors of coauthorship were selected, two (study type, topical scope of the study) associated with complexity and two (financial support for the project, popularity of the publishing journal) associated with competition. A negative binomial regression model was used to estimate the effects of each predictor on coauthorship incidence and growth. A second, mixed-effect model included the journal as a random effect. Results Coauthorship increased at about one author per article per decade. Clinical trials, supported research, and research of broader scope produced articles with more authors, while review articles credited fewer; and more popular journals published higher-authorship articles. Incidence and growth rates varied widely across journals and were themselves uncorrelated. Most effects remained statistically discernible after controlling for the publishing journal. The effects of complexity-associated factors held constant or diminished over time, while competition-related effects strengthened. These trends were similar in size but not discernible from subject-specific subdata. Conclusions Coauthorship incidence rates are multifactorial and vary with factors associated with both complexity and competition. Coauthorship growth is likewise multifactorial and increasingly associated with research competition. PMID:28329003
Brunson, Jason Cory; Wang, Xiaoyan; Laubenbacher, Reinhard C
2017-01-01
Investigations into the factors behind coauthorship growth in biomedical research have mostly focused on specific disciplines or journals, and have rarely controlled for factors in combination or considered changes in their effects over time. Observers often attribute the growth to the increasing complexity or competition (or both) of research practices, but few attempts have been made to parse the contributions of these two likely causes. We aimed to assess the effects of complexity and competition on the incidence and growth of coauthorship, using a sample of the biomedical literature spanning multiple journals and disciplines. Article-level bibliographic data from PubMed were combined with publicly available bibliometric data from Web of Science and SCImago over the years 1999-2007. We selected four predictors of coauthorship were selected, two (study type, topical scope of the study) associated with complexity and two (financial support for the project, popularity of the publishing journal) associated with competition. A negative binomial regression model was used to estimate the effects of each predictor on coauthorship incidence and growth. A second, mixed-effect model included the journal as a random effect. Coauthorship increased at about one author per article per decade. Clinical trials, supported research, and research of broader scope produced articles with more authors, while review articles credited fewer; and more popular journals published higher-authorship articles. Incidence and growth rates varied widely across journals and were themselves uncorrelated. Most effects remained statistically discernible after controlling for the publishing journal. The effects of complexity-associated factors held constant or diminished over time, while competition-related effects strengthened. These trends were similar in size but not discernible from subject-specific subdata. Coauthorship incidence rates are multifactorial and vary with factors associated with both complexity and competition. Coauthorship growth is likewise multifactorial and increasingly associated with research competition.
Should I Pack My Umbrella? Clinical versus Statistical Prediction of Mental Health Decisions
ERIC Educational Resources Information Center
Aegisdottir, Stefania; Spengler, Paul M.; White, Michael J.
2006-01-01
In this rejoinder, the authors respond to the insightful commentary of Strohmer and Arm, Chwalisz, and Hilton, Harris, and Rice about the meta-analysis on statistical versus clinical prediction techniques for mental health judgments. The authors address issues including the availability of statistical prediction techniques for real-life psychology…
Change Detection in Rough Time Series
2014-09-01
Business Statistics : An Inferential Approach, Dellen: San Francisco. [18] Winston, W. (1997) Operations Research Applications and Algorithms, Duxbury...distribution that can present significant challenges to conventional statistical tracking techniques. To address this problem the proposed method...applies hybrid fuzzy statistical techniques to series granules instead of to individual measures. Three examples demonstrated the robust nature of the
Enhancing Students' Ability to Use Statistical Reasoning with Everyday Problems
ERIC Educational Resources Information Center
Lawson, Timothy J.; Schwiers, Michael; Doellman, Maureen; Grady, Greg; Kelnhofer, Robert
2003-01-01
We discuss a technique for teaching students everyday applications of statistical concepts. We used this technique with students (n = 50) enrolled in several sections of an introductory statistics course; students (n = 45) in other sections served as a comparison group. A class of introductory psychology students (n = 24) served as a second…
Technical Note: The Initial Stages of Statistical Data Analysis
Tandy, Richard D.
1998-01-01
Objective: To provide an overview of several important data-related considerations in the design stage of a research project and to review the levels of measurement and their relationship to the statistical technique chosen for the data analysis. Background: When planning a study, the researcher must clearly define the research problem and narrow it down to specific, testable questions. The next steps are to identify the variables in the study, decide how to group and treat subjects, and determine how to measure, and the underlying level of measurement of, the dependent variables. Then the appropriate statistical technique can be selected for data analysis. Description: The four levels of measurement in increasing complexity are nominal, ordinal, interval, and ratio. Nominal data are categorical or “count” data, and the numbers are treated as labels. Ordinal data can be ranked in a meaningful order by magnitude. Interval data possess the characteristics of ordinal data and also have equal distances between levels. Ratio data have a natural zero point. Nominal and ordinal data are analyzed with nonparametric statistical techniques and interval and ratio data with parametric statistical techniques. Advantages: Understanding the four levels of measurement and when it is appropriate to use each is important in determining which statistical technique to use when analyzing data. PMID:16558489
The neonatal brain in critical congenital heart disease: Insights and future directions.
Peyvandi, Shabnam; Latal, Beatrice; Miller, Steven P; McQuillen, Patrick S
2018-05-19
Neurodevelopmental outcomes are impaired in survivors of critical congenital heart disease (CHD) in several developmental domains including motor, cognitive and sensory outcomes. These deficits can extend into the adolescent and early adulthood years. The cause of these neurodevelopmental impairments is multi-factorial and includes patient specific risk factors, cardiac anatomy and physiology as well as brain changes seen on MRI. Advances in imaging techniques have identified delayed brain development in the neonate with critical CHD as well as acquired brain injury. These abnormalities are seen even before corrective neonatal cardiac surgery. This review focuses on describing brain changes seen on MRI in neonates with CHD, risk factors for these changes and the association with neurodevelopmental outcome. There is an emerging focus on the impact of cardiovascular physiology on brain health and the complex heart-brain interplay that influences ultimate neurodevelopmental outcome in these patients. Copyright © 2018. Published by Elsevier Inc.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mittal, B.
1985-06-01
Decrease in penile blood flow has been implicated as the cause of erectile impotence in patients receiving pelvic irradiation. To determine any changes in the penile circulation secondary to pelvic irradiation, the authors measured the penile blood flow before and 6-9 months following completion of irradiation in six patients with prostate cancer. None of these patients had hormonal manipulation. The non-invasive techniques of Penile Brachial Index (PBI) and Penile Flow Index (PFI) were used to study penile circulation. Two patients developed impotence 2 to 4 1/2 months following completion of irradiation. There was no significant change in penile blood flowmore » following irradiation in any of the six patients studied. The etiology of post-irradiation impotence is probably multifactorial and it may be an oversimplification to attribute it to a single organic cause.« less
Nuances of Morphology in Myelodysplastic Diseases in the Age of Molecular Diagnostics.
Shaver, Aaron C; Seegmiller, Adam C
2017-10-01
Morphologic dysplasia is an important factor in diagnosis of myelodysplastic syndrome (MDS). However, the role of dysplasia is changing as new molecular genetic and genomic technologies take a more prominent place in diagnosis. This review discusses the role of morphology in the diagnosis of MDS and its interactions with cytogenetic and molecular testing. Recent changes in diagnostic criteria have attempted to standardize approaches to morphologic diagnosis of MDS, recognizing significant inter-observer variability in assessment of dysplasia. Definitive correlates between cytogenetic/molecular and morphologic findings have been described in only a small set of cases. However, these genetic and morphologic tools do play a complementary role in the diagnosis of both MDS and other myeloid neoplasms. Diagnosis of MDS requires a multi-factorial approach, utilizing both traditional morphologic as well as newer molecular genetic techniques. Understanding these tools, and the interplay between them, is crucial in the modern diagnosis of myeloid neoplasms.
Fisher-Owens, Susan
2014-01-01
Dental caries is not just the most common chronic childhood disease, with not insignificant burden of disease during childhood, but also lifelong impact. Traditional models that focus on the "mouth in the chair" have been helpful but insufficient to identify structural root causes for its high incidence, thus having a limited ability to prevent the disease. The addition of social and behavioral determinants to strictly biologic models provides the full context of care, enabling providers to better tailor their guidance and improve health outcomes. In-office behavioral management involves understanding these determinants and applying appropriate techniques; these not only can help reset family and patient expectations but can actually increase compliance. Lastly, children with multiple medical issues require additional focus, as they can carry greater burden of disease, making it even more critical during office visits to offer multifactorial compliance strategies for these patients and their parents.
[Insight into illness: an overview of the concept focusing on schizophrenia].
Bottlender, Ronald; Hloucal, Teresa-Maria
2010-03-01
Insight into illness is key to successful treatment. Poor insight, especially in schizophrenia, is, however, quite a frequent phenomenon that is also associated with poor adherence to treatment and a variety of unfavorable outcome parameters. On that background, the concept of insight into illness has gained new reseach interest during the last 10 years. The present review aims to report new findings regarding conceptual changes of insight, findings on the etiology, contributing factors as well as the assessment and methods to develop insight. Based on a review of the literature, results from more recent studies on insight into illness will be presented. Insight into illness is a complex, multidimensional, strongly culturally embedded phenomenon that is influenced by a variety of factors. The etiology of insight still remains poorly understood but is likely to be multifactorial including psychological, neuropsychological and organic reasons. Further research is needed, in particularly regarding therapeutical techniques to improve insight into illness.
Refractory pain following hip arthroscopy: evaluation and management
de SA, Darren L; Burnham, Jeremy M; Mauro, Craig S
2018-01-01
ABSTRACT With increased knowledge and understanding of hip pathology, hip arthroscopy is rapidly becoming a popular treatment option for young patients with hip pain. Despite improved clinical and radiographic outcomes with arthroscopic treatment, some patients may have ongoing pain and less than satisfactory outcomes. While the reasons leading to failed hip arthroscopy are multifactorial, patient selection, surgical technique and rehabilitation all play a role. Patients with failed hip arthroscopy should undergo a thorough history and physical examination, as well as indicated imaging. A treatment plan should then be developed based on pertinent findings from the workup and in conjunction with the patient. Depending on the etiology of failed hip arthroscopy, management may be nonsurgical or surgical, which may include revision arthroscopic or open surgery, periacetabular osteotomy or joint arthroplasty. Revision surgery may be appropriate in settings including, but not limited to, incompletely treated femoroacetabular impingement, postoperative adhesions, heterotopic ossification, instability, hip dysplasia or advanced degeneration. PMID:29423245
Laforest, Sophie; Lorthios-Guilledroit, Agathe; Nour, Kareen; Parisien, Manon; Fournier, Michel; Ellemberg, Dave; Guay, Danielle; Desgagn�s-Cyr, Charles-�mile; Bier, Nathalie
2017-01-01
Abstract This study examined the effects on attitudes and lifestyle behavior of Jog your Mind, a multi-factorial community-based program promoting cognitive vitality among seniors with no known cognitive impairment. A quasi-experimental study was conducted. Twenty-three community organizations were assigned either to the experimental group (offering the program) or to the control group (creating a waiting list). They recruited 294 community-dwelling seniors. The aims of the study were to verify the effects of the program on attitudes and behaviors related to cognitive vitality and to explore its effects on cognitive vitality. Data was collected at baseline and after the program. Regression analyses revealed that, following their participation in the program, experimental group participants reported: (i) in terms of attitudes, having a greater feeling of control concerning their cognitive capacities, (ii) in terms of behaviors, using significantly more memory strategies and practicing more physical activity and stimulating activities than control group participants. However, the program had no significant effects on measures of cognitive vitality. This study supports the fact that a multi-factorial community-based program can have significant effects on seniors’ attitudes and lifestyle behaviors related to cognitive vitality but at short term, no effects on cognitive vitality it-self were found. PMID:28334988
TROPHI: development of a tool to measure complex, multi-factorial patient handling interventions.
Fray, Mike; Hignett, Sue
2013-01-01
Patient handling interventions are complex and multi-factorial. It has been difficult to make comparisons across different strategies due to the lack of a comprehensive outcome measurement method. The Tool for Risk Outstanding in Patient Handling Interventions (TROPHI) was developed to address this gap by measuring outcomes and comparing performance across interventions. Focus groups were held with expert patient handling practitioners (n = 36) in four European countries (Finland, Italy, Portugal and the UK) to identify preferred outcomes to be measured for interventions. A systematic literature review identified 598 outcome measures; these were critically appraised and the most appropriate measurement tool was selected for each outcome. TROPHI was evaluated in the four EU countries (eight sites) and by an expert panel (n = 16) from the European Panel of Patient Handling Ergonomics for usability and practical application. This final stage added external validity to the research by exploring transferability potential and presenting the data and analysis to allow respondent (participant) validation. Patient handling interventions are complex and multi-factorial and it has been difficult to make comparisons due to the lack of a comprehensive outcome measurement method. The Tool for Risk Outstanding in Patient Handling Interventions (TROPHI) was developed to address this gap by measuring outcomes to compare performance across interventions.
Neyens, Jacques C L; Dijcks, Béatrice P J; Twisk, Jos; Schols, Jos M G A; van Haastregt, Jolanda C M; van den Heuvel, Wim J A; de Witte, Luc P
2009-03-01
to evaluate the effectiveness of a multifactorial intervention on incidence of falls in psychogeriatric nursing home patients. cluster-randomised controlled 12-month trial. psychogeriatric wards in 12 nursing homes in The Netherlands. psychogeriatric nursing home patients (n = 518). a general medical assessment and an additional specific fall risk evaluation tool, applied by a multidisciplinary fall prevention team, resulting in general and individual fall prevention activities. falls. there were 355 falls in 169.5 patient-years (2.09 falls per patient per year) in the intervention group and 422 falls in 166.3 patient-years (2.54 falls per patient per year) in the control group. Intention-to-treat analysis with adjustment for ward-related and patient-related parameters, and intra-cluster correlation, showed that the intervention group had a significantly lower mean fall incidence rate than the control group (rate ratio = 0.64, 95% CI = 0.43-0.96, P = 0.029). Subgroup analyses showed that fall risk declined further as patients participated longer in the intervention programme. the introduction of a structured multifactorial intervention to prevent falls in psychogeriatric nursing home patients significantly reduces the number of falls. This reduction is substantial and of high clinical relevance.
Horikawa, Yukio
2018-02-06
Maturity-onset diabetes of the young (MODY) is a form of diabetes classically characterized as having autosomal dominant inheritance, onset before the age of 25 years in at least one family member and partly preserved pancreatic β-cell function. The 14 responsible genes are reported to be MODY type 1~14, of which MODY 2 and 3 might be the most common forms. Although MODY is currently classified as diabetes of a single gene defect, it has become clear that mutations in rare MODYs, such as MODY 5 and MODY 6, have small mutagenic effects and low penetrance. In addition, as there are differences in the clinical phenotypes caused by the same mutation even in the same family, other phenotypic modifying factors are thought to exist; MODY could well have characteristics of type 2 diabetes mellitus, which is of multifactorial origin. Here, we outline the effects of genetic and environmental factors on the known phenotypes of MODY, focusing mainly on the examples of MODY 5 and 6, which have low penetrance, as suggestive models for elucidating the multifactorial origin of type 2 diabetes mellitus. © 2018 The Authors. Journal of Diabetes Investigation published by Asian Association for the Study of Diabetes (AASD) and John Wiley & Sons Australia, Ltd.
Valachi, Bethany; Valachi, Keith
2003-12-01
The authors reviewed studies to identify methods for dental operators to use to prevent the development of musculoskeletal disorders, or MSDs. The authors reviewed studies that related to the prevention of MSDs among dental operators. Some studies investigated the relationship between the biomechanics of seated working postures and physiological damage or pain. Other studies suggested that repeated unidirectional twisting of the trunk can lead to low back pain, while yet other studies examined the detrimental effects of working in one position for prolonged periods. Additional studies confirmed the roles that operators' flexibility and core strength can play in balanced musculoskeletal health and the need for operators to know how to properly adjust ergonomic equipment. This review indicates that strategies to prevent the multifactorial problem of dental operators' developing MSDs exist. These strategies address deficiencies in operator position, posture, flexibility, strength and ergonomics. Education and additional research are needed to promote an understanding of the complexity of the problem and to address the problem's multifactorial nature. A comprehensive approach to address the problem of MSDs in dentistry represents a paradigm shift in how operators work. New educational models that incorporate a multifactorial approach can be developed to help dental operators manage and prevent MSDs effectively.
Preventing Falls in Older Persons.
Moncada, Lainie Van Voast; Mire, L Glen
2017-08-15
The American Geriatrics Society and British Geriatrics Society recommend that all adults older than 65 years be screened annually for a history of falls or balance impairment. The U.S. Preventive Services Task Force and American Academy of Family Physicians recommend exercise or physical therapy and vitamin D supplementation to prevent falls in community-dwelling older adults who are at increased risk of falls. Although the U.S. Preventive Services Task Force and American Academy of Family Physicians do not recommend routine multifactorial intervention to prevent falls in all community-dwelling older adults, they state that it may be appropriate in individual cases. The Centers for Disease Control and Prevention developed an algorithm to aid in the implementation of the American Geriatrics Society/British Geriatrics Society guideline. The algorithm suggests assessment and multifactorial intervention for those who have had two or more falls or one fall-related injury. Multifactorial interventions should include exercise, particularly balance, strength, and gait training; vitamin D supplementation with or without calcium; management of medications, especially psychoactive medications; home environment modification; and management of postural hypotension, vision problems, foot problems, and footwear. These interventions effectively decrease falls in the community, hospital, and nursing home settings. Fall prevention is reimbursed as part of the Medicare Annual Wellness Visit.
Pedersen, Mette B; Giraldi, Annamaria; Kristensen, Ellids; Lauritzen, Torsten; Sandbæk, Annelli; Charles, Morten
2015-03-01
Sexual problems are common in people with diabetes. It is unknown whether early detection of diabetes and subsequent intensive multifactorial treatment (IT) are associated with sexual health. We report the prevalence of low sexual desire and low sexual satisfaction among people with screen-detected diabetes and compare the impact of intensive multifactorial treatment with the impact of routine care (RC) on these measures. A cross-sectional analysis of the ADDITION-Denmark trial cohort six years post-diagnosis. 190 general practices around Denmark. A total of 968 patients with screen-detected type 2 diabetes. Low sexual desire and low sexual satisfaction. Mean (standard deviation, SD) age was 64.9 (6.9) years. The prevalence of low sexual desire was 53% (RC) and 54% (IT) among women, and 24% (RC) and 25% (IT) among men. The prevalence of low sexual satisfaction was 23% (RC) and 18% (IT) among women, and 27% (RC) and 37% (IT) among men. Among men, the prevalence of low sexual satisfaction was significantly higher in the IT group than in the RC group, p = 0.01. Low sexual desire and low satisfaction are frequent among men and women with screen-detected diabetes, and IT may negatively impact men's sexual satisfaction.
Novel Strategies to Improve Resident Selection by Improving Cultural Fit: AOA Critical Issues.
Porter, Scott E; Razi, Afshin E; Ramsey, T Bennett
2017-11-15
Residency selection is a perennial multifactorial process that differs considerably from the recruitment processes that other professional occupations enjoy. The 2016 meeting of the American Orthopaedic Association's Council of Orthopaedic Residency Directors highlighted a series of symposia that sought to present a novel manner of resident selection. Specifically, the presenters for each symposium were asked to do the following: present some general recruitment best practices in industries outside of medicine, present how branding of a program may translate into a better interview season, investigate evidence that the applicant pool to orthopaedic surgery may have changed and that residency program brands may have to reflect this, and assess our current evaluation techniques for talent identification and resident selection with respect to a specific department's appearance or brand. The meeting concluded with an understanding of the level to which programs can successfully create or adopt a brand and how this may go a long way in focusing the entire match process and allow emphasis to be placed on applicants who possess desired traits. The goal for this meeting was that attendees would leave with tangible practices and techniques that could be adopted at their home institutions.
Paiva, Sara; Carneiro, Márcia Mendonça
2013-01-01
Chronic pelvic pain (CPP) is defined as pain of at least 6 months' duration that occurs in the lower abdomen or below the umbilicus and has resulted in functional or psychological disability or required intervention and treatment. Therapeutic interventions center around the treatment of CPP as a diagnosis in and of itself, and treatment of specific disorders that may be related to CPP. A multidisciplinary approach for diagnosis and treatment seems to be most effective for symptomatic relief. This paper reviews the evidence for such interventions as psychological treatments including the use of complementary and alternative medicine techniques for CPP in women. Unfortunately, finding the best evidence in this setting is difficult as only very few randomized controlled trials are available. A combination of treatments is usually required over time for the treatment of refractory CPP. The multifactorial nature of CPP needs to be discussed with the patient and a good rapport as well as a partnership needs to be developed to plan a management program with regular followup. Promotion of a multidisciplinary approach which includes complementary and alternative medicine techniques in managing CPP in women seems to yield the best results.
Direct Midline Diastema Closure with Composite Layering Technique: A One-Year Follow-Up.
Korkut, Bora; Yanikoglu, Funda; Tagtekin, Dilek
2016-01-01
Objective. Maxillary anterior spacing is a common aesthetic complaint of patients. Midline diastema has a multifactorial etiology such as labial frenulum, microdontia, mesiodens, peg-shaped lateral incisors, agenesis, cysts, habits such as finger sucking, tongue thrusting, or lip sucking, dental malformations, genetics, proclinations, dental-skeletal discrepancies, and imperfect coalescence of interdental septum. Appropriate technique and material for effective treatment are based on time, physical, psychological, and economical limitations. Direct composite resins in diastema cases allow dentist and patient complete control of these limitations and formation of natural smile. Clinical Considerations. In this case report a maxillary midline diastema was closed with direct composite resin restorations in one appointment without any preparation. One bottle total etch adhesive was used and translucent/opaque composite resin shades were layered on mesial surfaces of the teeth that were isolated with rubber dam and Teflon bands. Finishing and polishing procedures were achieved by using polishing discs. Patient was informed for recalls for every 6 months. Conclusions. At one-year recall no sensitivities, discolorations, or fractures were detected on teeth and restorations. Direct composite resins seemed to be highly aesthetic and durable restorations that can satisfy patients as under the conditions of case presented.
Dietschi, Didier; Argente, Ana
2011-01-01
Tooth wear represents a frequent pathology with multifactorial origins. Behavioral changes, unbalanced diet, various medical conditions and medications inducing acid regurgitation or influencing saliva composition and flow rate, trigger tooth erosion. Awake and sleep bruxism, which are widespread nowadays with functional disorders, induce attrition. It has become increasingly important to diagnose early signs of tooth wear so that proper preventive, and if needed, restorative measures are taken. Such disorders have biological, functional, and also esthetic consequences. Following a comprehensive clinical evaluation, treatment objectives, such as a proper occlusal and anatomical scheme as well as a pleasing smile line, are usually set on models with an anterior teeth full-mouth waxup, depending on the severity of tissue loss. Based on the new vertical dimension of occlusion (VDO), combinations of direct and indirect restorations can then help to reestablish anatomy and function. The use of adhesive techniques and resin composites has demonstrated its potential, in particular for the treatment of moderate tooth wear. Part I of this article reviews recent knowledge and clinical concepts dealing with the various forms of early restorative interventions and their potential to restrict ongoing tissue destruction.
Root coverage with Emdogain/AlloDerm: a new way to treat gingival recessions.
Saadoun, André P
2008-01-01
The recession of the gingival margin is becoming a more prominent condition in the oral situation of many patients and should be treated at its earliest detection. The multifactorial etiology, decision modality, and current trends in the treatment of gingival recession are discussed in this article. The surgical technique of choice depends on several factors, but among the different surgical protocols available, the clinician should select one that will minimize surgical trauma and achieve predictable esthetic results. All of the approaches described in this article can effectively treat deep and shallow Class I or II buccal recessions. Recently, as an alternative to autogenous gingival grafts in root coverage procedures, enamel matrix derivative (Emdogain) and acellular dermal matrix allograft (AlloDerm) were utilized to correct these gingival defects, negating the morbidity and the requirement for a second palatal surgical procedure. Emdogain or AlloDerm materials used alone or in combination are a predictable treatment for root coverage, are relatively easy to perform (although they are technique sensitive), present low patient morbidity, offer a significant increase in the percentage of root coverage and amount of keratinized tissue, and should be part of the periodontal plastic surgery armamentarium.
Are Assumptions of Well-Known Statistical Techniques Checked, and Why (Not)?
Hoekstra, Rink; Kiers, Henk A. L.; Johnson, Addie
2012-01-01
A valid interpretation of most statistical techniques requires that one or more assumptions be met. In published articles, however, little information tends to be reported on whether the data satisfy the assumptions underlying the statistical techniques used. This could be due to self-selection: Only manuscripts with data fulfilling the assumptions are submitted. Another explanation could be that violations of assumptions are rarely checked for in the first place. We studied whether and how 30 researchers checked fictitious data for violations of assumptions in their own working environment. Participants were asked to analyze the data as they would their own data, for which often used and well-known techniques such as the t-procedure, ANOVA and regression (or non-parametric alternatives) were required. It was found that the assumptions of the techniques were rarely checked, and that if they were, it was regularly by means of a statistical test. Interviews afterward revealed a general lack of knowledge about assumptions, the robustness of the techniques with regards to the assumptions, and how (or whether) assumptions should be checked. These data suggest that checking for violations of assumptions is not a well-considered choice, and that the use of statistics can be described as opportunistic. PMID:22593746
Evaluation of Three Different Processing Techniques in the Fabrication of Complete Dentures
Chintalacheruvu, Vamsi Krishna; Balraj, Rajasekaran Uttukuli; Putchala, Lavanya Sireesha; Pachalla, Sreelekha
2017-01-01
Aims and Objectives: The objective of the present study is to compare the effectiveness of three different processing techniques and to find out the accuracy of processing techniques through number of occlusal interferences and increase in vertical dimension after denture processing. Materials and Methods: A cross-sectional study was conducted on a sample of 18 patients indicated for complete denture fabrication was selected for the study and they were divided into three subgroups. Three processing techniques, compression molding and injection molding using prepolymerized resin and unpolymerized resin, were used to fabricate dentures for each of the groups. After processing, laboratory-remounted dentures were evaluated for number of occlusal interferences in centric and eccentric relations and change in vertical dimension through vertical pin rise in articulator. Data were analyzed using statistical test ANOVA and SPSS software version 19.0 by IBM was used. Results: Data obtained from three groups were subjected to one-way ANOVA test. After ANOVA test, results with significant variations were subjected to post hoc test. Number of occlusal interferences with compression molding technique was reported to be more in both centric and eccentric positions as compared to the two injection molding techniques with statistical significance in centric, protrusive, right lateral nonworking, and left lateral working positions (P < 0.05). Mean vertical pin rise (0.52 mm) was reported to more in compression molding technique as compared to injection molding techniques, which is statistically significant (P < 0.001). Conclusions: Within the limitations of this study, injection molding techniques exhibited less processing errors as compared to compression molding technique with statistical significance. There was no statistically significant difference in processing errors reported within two injection molding systems. PMID:28713763
Evaluation of Three Different Processing Techniques in the Fabrication of Complete Dentures.
Chintalacheruvu, Vamsi Krishna; Balraj, Rajasekaran Uttukuli; Putchala, Lavanya Sireesha; Pachalla, Sreelekha
2017-06-01
The objective of the present study is to compare the effectiveness of three different processing techniques and to find out the accuracy of processing techniques through number of occlusal interferences and increase in vertical dimension after denture processing. A cross-sectional study was conducted on a sample of 18 patients indicated for complete denture fabrication was selected for the study and they were divided into three subgroups. Three processing techniques, compression molding and injection molding using prepolymerized resin and unpolymerized resin, were used to fabricate dentures for each of the groups. After processing, laboratory-remounted dentures were evaluated for number of occlusal interferences in centric and eccentric relations and change in vertical dimension through vertical pin rise in articulator. Data were analyzed using statistical test ANOVA and SPSS software version 19.0 by IBM was used. Data obtained from three groups were subjected to one-way ANOVA test. After ANOVA test, results with significant variations were subjected to post hoc test. Number of occlusal interferences with compression molding technique was reported to be more in both centric and eccentric positions as compared to the two injection molding techniques with statistical significance in centric, protrusive, right lateral nonworking, and left lateral working positions ( P < 0.05). Mean vertical pin rise (0.52 mm) was reported to more in compression molding technique as compared to injection molding techniques, which is statistically significant ( P < 0.001). Within the limitations of this study, injection molding techniques exhibited less processing errors as compared to compression molding technique with statistical significance. There was no statistically significant difference in processing errors reported within two injection molding systems.
Xiong, Jie; Zhou, Tong
2012-01-01
An important problem in systems biology is to reconstruct gene regulatory networks (GRNs) from experimental data and other a priori information. The DREAM project offers some types of experimental data, such as knockout data, knockdown data, time series data, etc. Among them, multifactorial perturbation data are easier and less expensive to obtain than other types of experimental data and are thus more common in practice. In this article, a new algorithm is presented for the inference of GRNs using the DREAM4 multifactorial perturbation data. The GRN inference problem among [Formula: see text] genes is decomposed into [Formula: see text] different regression problems. In each of the regression problems, the expression level of a target gene is predicted solely from the expression level of a potential regulation gene. For different potential regulation genes, different weights for a specific target gene are constructed by using the sum of squared residuals and the Pearson correlation coefficient. Then these weights are normalized to reflect effort differences of regulating distinct genes. By appropriately choosing the parameters of the power law, we constructe a 0-1 integer programming problem. By solving this problem, direct regulation genes for an arbitrary gene can be estimated. And, the normalized weight of a gene is modified, on the basis of the estimation results about the existence of direct regulations to it. These normalized and modified weights are used in queuing the possibility of the existence of a corresponding direct regulation. Computation results with the DREAM4 In Silico Size 100 Multifactorial subchallenge show that estimation performances of the suggested algorithm can even outperform the best team. Using the real data provided by the DREAM5 Network Inference Challenge, estimation performances can be ranked third. Furthermore, the high precision of the obtained most reliable predictions shows the suggested algorithm may be helpful in guiding biological experiment designs.
Fairhall, Nicola; Sherrington, Catherine; Kurrle, Susan E; Lord, Stephen R; Lockwood, Keri; Howard, Kirsten; Hayes, Alison; Monaghan, Noeline; Langron, Colleen; Aggar, Christina; Cameron, Ian D
2015-01-01
To compare the costs and cost-effectiveness of a multifactorial interdisciplinary intervention versus usual care for older people who are frail. Cost-effectiveness study embedded within a randomized controlled trial. Community-based intervention in Sydney, Australia. A total of 241 community-dwelling people 70 years or older who met the Cardiovascular Health Study criteria for frailty. A 12-month multifactorial, interdisciplinary intervention targeting identified frailty characteristics versus usual care. Health and social service use, frailty, and health-related quality of life (EQ-5D) were measured over the 12-month intervention period. The difference between the mean cost per person for 12 months in the intervention and control groups (incremental cost) and the ratio between incremental cost and effectiveness were calculated. A total of 216 participants (90%) completed the study. The prevalence of frailty was 14.7% lower in the intervention group compared with the control group at 12 months (95% CI 2.4%-27.0%; P = .02). There was no significant between-group difference in EQ-5D utility scores. The cost for 1 extra person to transition out of frailty was $A15,955 (at 2011 prices). In the "very frail" subgroup (participants met >3 Cardiovascular Health Study frailty criteria), the intervention was both more effective and less costly than the control. A cost-effectiveness acceptability curve shows that the intervention would be cost-effective with 80% certainty if decision makers were willing to pay $A50,000 per extra person transitioning from frailty. In the very frail subpopulation, this reduced to $25,000. For frail older people residing in the community, a 12-month multifactorial intervention provided better value for money than usual care, particularly for the very frail, in whom it has a high probability of being cost saving, as well as effective. Trial registration: ACTRN12608000250336. Copyright © 2015 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.
Pelletier, K R
1997-12-01
This paper is a critical review of the clinical and cost outcome evaluation studies of multifactorial, comprehensive, cardiovascular risk management programs in worksites. A comprehensive international literature search conducted under the auspices of the National Heart, Lung and Blood Institute identified 17 articles based on 12 studies that examined the clinical outcomes of multifactorial, comprehensive programs. These articles were identified through MEDLINE, manual searches of recent journals, and through direct inquiries to worksite health promotion researchers. All studies were conducted between 1978 and 1995, with 1978 being the date of the first citation of a methodologically rigorous evaluation. Of the 12 research studies, only 8 utilized the worksite as both the unit of assignment and as the unit of analysis. None of the studies analyzed adequately for cost effectiveness. Given this limitation, this review briefly considers the relevant worksite research that has demonstrated cost outcomes. Worksite-based, multifactorial cardiovascular intervention programs reviewed for this article varied widely in the comprehensiveness, intensity, and duration of both the interventions and evaluations. Results from randomized trials suggest that providing opportunities for individualized, cardiovascular risk reduction counseling for high-risk employees within the context of comprehensive programming may be the critical component of an effective worksite intervention. Despite the many limitations of the current methodologies of the 12 studies, the majority of the research to date indicates the following: (1) favorable clinical and cost outcomes; (2) that more recent and more rigorously designed research tends to support rather than refute earlier and less rigorously designed studies; and (3) that rather than interpreting the methodological flaws and diversity as inherently negative, one may consider it as indicative of a robust phenomena evident in many types of worksites, with diverse employees, differing interventions, and varying degrees of methodological sophistication. Results of these studies reviewed provide both cautious optimism about the effectiveness of these worksite programs and insights regarding the essential components and characteristics of successful programs.
In analyses supporting the development of numeric nutrient criteria, multiple statistical techniques can be used to extract critical values from stressor response relationships. However there is little guidance for choosing among techniques, and the extent to which log-transfor...
Incorporating Nonparametric Statistics into Delphi Studies in Library and Information Science
ERIC Educational Resources Information Center
Ju, Boryung; Jin, Tao
2013-01-01
Introduction: The Delphi technique is widely used in library and information science research. However, many researchers in the field fail to employ standard statistical tests when using this technique. This makes the technique vulnerable to criticisms of its reliability and validity. The general goal of this article is to explore how…
ERIC Educational Resources Information Center
Karadag, Engin
2010-01-01
To assess research methods and analysis of statistical techniques employed by educational researchers, this study surveyed unpublished doctoral dissertation from 2003 to 2007. Frequently used research methods consisted of experimental research; a survey; a correlational study; and a case study. Descriptive statistics, t-test, ANOVA, factor…
Statistics in the Workplace: A Survey of Use by Recent Graduates with Higher Degrees
ERIC Educational Resources Information Center
Harraway, John A.; Barker, Richard J.
2005-01-01
A postal survey was conducted regarding statistical techniques, research methods and software used in the workplace by 913 graduates with PhD and Masters degrees in the biological sciences, psychology, business, economics, and statistics. The study identified gaps between topics and techniques learned at university and those used in the workplace,…
Statistical approach for selection of biologically informative genes.
Das, Samarendra; Rai, Anil; Mishra, D C; Rai, Shesh N
2018-05-20
Selection of informative genes from high dimensional gene expression data has emerged as an important research area in genomics. Many gene selection techniques have been proposed so far are either based on relevancy or redundancy measure. Further, the performance of these techniques has been adjudged through post selection classification accuracy computed through a classifier using the selected genes. This performance metric may be statistically sound but may not be biologically relevant. A statistical approach, i.e. Boot-MRMR, was proposed based on a composite measure of maximum relevance and minimum redundancy, which is both statistically sound and biologically relevant for informative gene selection. For comparative evaluation of the proposed approach, we developed two biological sufficient criteria, i.e. Gene Set Enrichment with QTL (GSEQ) and biological similarity score based on Gene Ontology (GO). Further, a systematic and rigorous evaluation of the proposed technique with 12 existing gene selection techniques was carried out using five gene expression datasets. This evaluation was based on a broad spectrum of statistically sound (e.g. subject classification) and biological relevant (based on QTL and GO) criteria under a multiple criteria decision-making framework. The performance analysis showed that the proposed technique selects informative genes which are more biologically relevant. The proposed technique is also found to be quite competitive with the existing techniques with respect to subject classification and computational time. Our results also showed that under the multiple criteria decision-making setup, the proposed technique is best for informative gene selection over the available alternatives. Based on the proposed approach, an R Package, i.e. BootMRMR has been developed and available at https://cran.r-project.org/web/packages/BootMRMR. This study will provide a practical guide to select statistical techniques for selecting informative genes from high dimensional expression data for breeding and system biology studies. Published by Elsevier B.V.
Techniques in teaching statistics : linking research production and research use.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Martinez-Moyano, I .; Smith, A.; Univ. of Massachusetts at Boston)
In the spirit of closing the 'research-practice gap,' the authors extend evidence-based principles to statistics instruction in social science graduate education. The authors employ a Delphi method to survey experienced statistics instructors to identify teaching techniques to overcome the challenges inherent in teaching statistics to students enrolled in practitioner-oriented master's degree programs. Among the teaching techniques identi?ed as essential are using real-life examples, requiring data collection exercises, and emphasizing interpretation rather than results. Building on existing research, preliminary interviews, and the ?ndings from the study, the authors develop a model describing antecedents to the strength of the link between researchmore » and practice.« less
Statistical Symbolic Execution with Informed Sampling
NASA Technical Reports Server (NTRS)
Filieri, Antonio; Pasareanu, Corina S.; Visser, Willem; Geldenhuys, Jaco
2014-01-01
Symbolic execution techniques have been proposed recently for the probabilistic analysis of programs. These techniques seek to quantify the likelihood of reaching program events of interest, e.g., assert violations. They have many promising applications but have scalability issues due to high computational demand. To address this challenge, we propose a statistical symbolic execution technique that performs Monte Carlo sampling of the symbolic program paths and uses the obtained information for Bayesian estimation and hypothesis testing with respect to the probability of reaching the target events. To speed up the convergence of the statistical analysis, we propose Informed Sampling, an iterative symbolic execution that first explores the paths that have high statistical significance, prunes them from the state space and guides the execution towards less likely paths. The technique combines Bayesian estimation with a partial exact analysis for the pruned paths leading to provably improved convergence of the statistical analysis. We have implemented statistical symbolic execution with in- formed sampling in the Symbolic PathFinder tool. We show experimentally that the informed sampling obtains more precise results and converges faster than a purely statistical analysis and may also be more efficient than an exact symbolic analysis. When the latter does not terminate symbolic execution with informed sampling can give meaningful results under the same time and memory limits.
Maciel, Paula Curitiba; Veiga-Filho, Joel; Carvalho, Marcelo Prado; Fonseca, Fernando Elias Martins; Ferreira, Lydia Masako; Veiga, Daniela Francescato
2014-01-01
Cancer is a multifactorial disease and skin carcinomas are the most common type of cancer. Assessing quality of life and self-esteem outcomes in skin cancer patients is important because these are indicators of the results of the treatment, translating how patients face their lives and their personal relationships. To assess the late impact of the surgical treatment of head and/or neck skin carcinomas on quality of life and self-esteem of the patients. Fifty patients with head or neck skin carcinomas were enrolled. Their age ranged between 30 and 75 years, 27 were men and 23 were women. Patients were assessed with regard to quality of life and self-esteem, preoperatively and five years postoperatively. Validated instruments were used: the MOS 36-item Short-form Health Survey (SF-36) and the Rosenberg Self-esteem/EPM-UNIFESP Scale. The Wilcoxon signed-rank test was used for the statistical analysis. Twenty-two patients completed the five-year follow-up, 54.5% women and 45.5% men. Compared to the preoperative assessment, patients had an improvement in mental health (p=0.011) and in self-esteem (p=0.002). There was no statistical difference with regard to the other domains of the SF-36. Patients submitted to surgical treatment of skin carcinoma improved mental health and self-esteem in the late postsurgical testing.
Maciel, Paula Curitiba; Veiga-Filho, Joel; de Carvalho, Marcelo Prado; Fonseca, Fernando Elias Martins; Ferreira, Lydia Masako; Veiga, Daniela Francescato
2014-01-01
BACKGROUND Cancer is a multifactorial disease and skin carcinomas are the most common type of cancer. Assessing quality of life and self-esteem outcomes in skin cancer patients is important because these are indicators of the results of the treatment, translating how patients face their lives and their personal relationships. OBJECTIVE To assess the late impact of the surgical treatment of head and/or neck skin carcinomas on quality of life and self-esteem of the patients. METHODS Fifty patients with head or neck skin carcinomas were enrolled. Their age ranged between 30 and 75 years, 27 were men and 23 were women. Patients were assessed with regard to quality of life and self-esteem, preoperatively and five years postoperatively. Validated instruments were used: the MOS 36-item Short-form Health Survey (SF-36) and the Rosenberg Self-esteem/EPM-UNIFESP Scale. The Wilcoxon signed-rank test was used for the statistical analysis. RESULTS Twenty-two patients completed the five-year follow-up, 54.5% women and 45.5% men. Compared to the preoperative assessment, patients had an improvement in mental health (p=0.011) and in self-esteem (p=0.002). There was no statistical difference with regard to the other domains of the SF-36. CONCLUSION Patients submitted to surgical treatment of skin carcinoma improved mental health and self-esteem in the late postsurgical testing. PMID:25054746
Dermatoglyphics and Karyotype Analysis in Primary Amenorrhoea
Sontakke, Bharat R; Waghmare, Jwalant E; Tarnekar, Aditya M; Shende, Moreshwar R; Pal, Asoke K
2014-01-01
Background: Dermatoglyphics is the scientific study of the skin ridge patterns on the fingers, toes, palms of the hands and soles of feet. Dermatoglyphics is in use as a supportive diagnostic tool in genetic or chromosomal disorders as well as in clinical conditions with genetic etiologies. Primary amenorrhoea and Dermatoglyphics, both have the suspected multifactorial (genetic and environmental) aetiologies. Objective: In the present study the finger dermatoglyphic patterns were studied in primary amenorrhoea cases and age matched fertile control females and also attention was given to find out whether a specific dermatoglyphic trait exists in primary amenorrhoea cases and whether it was statistically significant. Materials and Methods: To study the role of dermatoglyphics in primary amenorrhoea, a study was conducted on 30 subjects with primary amenorrhoea (as cases) and compared it with equal number of age matched fertile females (as controls). We studied fingertip patterns in all the subjects enrolled. Simultaneously we have assessed the Karyotype of primary amenorrhoea cases. Result and Conclusion: Two subjects in experimental group have shown abnormal Karyotypes. The most significant finding in present study was increased total finger ridge count (TFRC) in primary amenorrhoea cases which was statistically significant. We also found higher frequency of loops and arches in primary amenorrhoea with abnormal karyotypes. This type of study may be quite useful as a supportive investigation, in stating the predisposition of an individual to primary amenorrhoea and referral of an individual for karyotyping. PMID:25653930
Carrier air wing mishap reduction using a human factors classification system and risk management.
Belland, Kxis M; Olsen, Cara; Lawry, Russell
2010-11-01
In 1998, the Navy's center of excellence for advanced air wing combat operations, namely the Naval Strike and Air Warfare Center (NSAWC), had a spike in Class A flight mishaps. The spike triggered an intense review of prior mishaps and current mishap-reduction practices using the Human Factors Analysis and Classification System (HFACS). The review resulted in NSAWC instituting a comprehensive multifactorial mishap reduction plan applying Operational Risk Management (ORM) precepts. This is a nonrandomized investigational study with use of a historical comparison population. The Class A mishap rate per flight hour covering 10 yr prior to the mishap reduction efforts was estimated and compared to the Class A mishap rate per flight hour for the 10 yr after implementation using Poisson regression. Combined Fleet and NSAWC data shows a 27% reduction in mishap rate, but the 21% reduction in the Fleet alone was not statistically significant. The mishap reduction at NSAWC was statistically significant with an 84% reduction. Fallon carrier air wing mishap rates post-ORM mishap reduction efforts are approaching those seen in the Fleet, but are still elevated overall (3.7 vs. 2.4). The incidence rate ratio was 80% lower at Fallon than the rest of the Fleet, indicating a significantly greater reduction in NSAWC air wing mishaps and suggests focused aviation mishap reduction efforts in similar circumstances could result in similar reductions.
The role of exercise in fall prevention for older adults.
Rose, Debra J; Hernandez, Danielle
2010-11-01
This article reviews the evidence for the effectiveness of stand-alone exercise interventions and multifactorial intervention strategies that include exercise in lowering fall incidence rates and/or fall risk among older adults residing in the community, acute, subacute, and long-term care settings. Stand-alone exercise programs that emphasize multiple exercise categories are effective in reducing fall rates and fall risk in community-residing older adults, and may also be effective when conducted for a sufficient duration with older adult patients in subacute settings. In contrast, multifactorial fall risk reduction programs that include exercise as a component and are delivered by a multidisciplinary team are more effective in lowering fall rates in long-term care settings. Copyright © 2010 Elsevier Inc. All rights reserved.
Longevity and aging. Mechanisms and perspectives.
Labat-Robert, J; Robert, L
2015-12-01
Longevity can mostly be determined with relative accuracy from birth and death registers when available. Aging is a multifactorial process, much more difficult to quantitate. Every measurable physiological function declines with specific speeds over a wide range. The mechanisms involved are also different, genetic factors are of importance for longevity determinations. The best-known genes involved are the Sirtuins, active at the genetic and epigenetic level. Aging is multifactorial, not "coded" in the genome. There are, however, a number of well-studied physical and biological parameters involved in aging, which can be determined and quantitated. We shall try to identify parameters affecting longevity as well as aging and suggest some reasonable predictions for the future. Copyright © 2015 Elsevier Masson SAS. All rights reserved.
Earth Observation System Flight Dynamics System Covariance Realism
NASA Technical Reports Server (NTRS)
Zaidi, Waqar H.; Tracewell, David
2016-01-01
This presentation applies a covariance realism technique to the National Aeronautics and Space Administration (NASA) Earth Observation System (EOS) Aqua and Aura spacecraft based on inferential statistics. The technique consists of three parts: collection calculation of definitive state estimates through orbit determination, calculation of covariance realism test statistics at each covariance propagation point, and proper assessment of those test statistics.
The Shock and Vibration Digest. Volume 16, Number 1
1984-01-01
investigation of the measure- ment of frequency band average loss factors of structural components for use in the statistical energy analysis method of...stiffness. Matrix methods Key Words: Finite element technique. Statistical energy analysis . Experimental techniques. Framed structures, Com- puter...programs In order to further understand the practical application of the statistical energy analysis , a two section plate-like frame structure is
NASA Technical Reports Server (NTRS)
Aires, Filipe; Rossow, William B.; Chedin, Alain; Hansen, James E. (Technical Monitor)
2000-01-01
The use of the Principal Component Analysis technique for the analysis of geophysical time series has been questioned in particular for its tendency to extract components that mix several physical phenomena even when the signal is just their linear sum. We demonstrate with a data simulation experiment that the Independent Component Analysis, a recently developed technique, is able to solve this problem. This new technique requires the statistical independence of components, a stronger constraint, that uses higher-order statistics, instead of the classical decorrelation a weaker constraint, that uses only second-order statistics. Furthermore, ICA does not require additional a priori information such as the localization constraint used in Rotational Techniques.
NASA Technical Reports Server (NTRS)
Wolf, S. F.; Lipschutz, M. E.
1993-01-01
Multivariate statistical analysis techniques (linear discriminant analysis and logistic regression) can provide powerful discrimination tools which are generally unfamiliar to the planetary science community. Fall parameters were used to identify a group of 17 H chondrites (Cluster 1) that were part of a coorbital stream which intersected Earth's orbit in May, from 1855 - 1895, and can be distinguished from all other H chondrite falls. Using multivariate statistical techniques, it was demonstrated that a totally different criterion, labile trace element contents - hence thermal histories - or 13 Cluster 1 meteorites are distinguishable from those of 45 non-Cluster 1 H chondrites. Here, we focus upon the principles of multivariate statistical techniques and illustrate their application using non-meteoritic and meteoritic examples.
Code of Federal Regulations, 2010 CFR
2010-07-01
..., other techniques, such as the use of statistical models or the use of historical data could be..., mathematical techniques should be applied to account for the trends to ensure that the expected annual values... emission patterns, either the most recent representative year(s) could be used or statistical techniques or...
The Use of a Context-Based Information Retrieval Technique
2009-07-01
provided in context. Latent Semantic Analysis (LSA) is a statistical technique for inferring contextual and structural information, and previous studies...WAIS). 10 DSTO-TR-2322 1.4.4 Latent Semantic Analysis LSA, which is also known as latent semantic indexing (LSI), uses a statistical and...1.4.6 Language Models In contrast, natural language models apply algorithms that combine statistical information with semantic information. Semantic
[Statistical analysis of German radiologic periodicals: developmental trends in the last 10 years].
Golder, W
1999-09-01
To identify which statistical tests are applied in German radiological publications, to what extent their use has changed during the last decade, and which factors might be responsible for this development. The major articles published in "ROFO" and "DER RADIOLOGE" during 1988, 1993 and 1998 were reviewed for statistical content. The contributions were classified by principal focus and radiological subspecialty. The methods used were assigned to descriptive, basal and advanced statistics. Sample size, significance level and power were established. The use of experts' assistance was monitored. Finally, we calculated the so-called cumulative accessibility of the publications. 525 contributions were found to be eligible. In 1988, 87% used descriptive statistics only, 12.5% basal, and 0.5% advanced statistics. The corresponding figures in 1993 and 1998 are 62 and 49%, 32 and 41%, and 6 and 10%, respectively. Statistical techniques were most likely to be used in research on musculoskeletal imaging and articles dedicated to MRI. Six basic categories of statistical methods account for the complete statistical analysis appearing in 90% of the articles. ROC analysis is the single most common advanced technique. Authors make increasingly use of statistical experts' opinion and programs. During the last decade, the use of statistical methods in German radiological journals has fundamentally improved, both quantitatively and qualitatively. Presently, advanced techniques account for 20% of the pertinent statistical tests. This development seems to be promoted by the increasing availability of statistical analysis software.
Van Zuilen, Arjan D; Wetzels, Jack F M; Bots, Michiel L; Van Blankestijn, Peter J
2008-01-01
Moderate to severe chronic kidney disease (CKD) is associated with increased cardiovascular risk. Usually nephrologists are primarily responsible for the care of CKD patients. However, in many cases treatment goals, as formulated in guidelines, are not met. The addition of a nurse practitioner might improve the quality of care. The Multifactorial Approach and Superior Treatment Efficacy in Renal Patients with the Aid of Nurse Practitioners (MASTERPLAN) study is a randomized controlled multicenter trial, aimed at investigating whether a multifactorial approach in patients with moderate to severe CKD (stage 3 and 4) to achieving treatment goals using both a polydrug strategy and lifestyle treatment either with or without the addition of a nurse practitioner will reduce cardiovascular risk and slow the decline of kidney function. Patients (n=793) have been randomized to nurse care or physician care. In the nurse-care arm of the study, nurse practitioners use flowcharts to address risk factors requiring drug and/or lifestyle modification. They have been trained to coach patients by motivational interviewing with the aim of improving patient self-management. At baseline, both treatment groups show equal distributions with regard to key variables in the study. Moreover, in only 1 patient were all risk factors within the limits as defined in various guidelines, which underscores the relevance of our initiative.
Onay, Ulaş; Akpınar, Sercan; Akgün, Rahmi Can; Balçık, Cenk; Tuncay, Ismail Cengiz
2013-01-01
The aim of this study was to compare new knotless single-row and double-row suture anchor techniques with traditional transosseous suture techniques for different sized rotator cuff tears in an animal model. The study included 56 cadaveric sheep shoulders. Supraspinatus cuff tears of 1 cm repaired with new knotless single-row suture anchor technique and supraspinatus and infraspinatus rotator cuff tears of 3 cm repaired with double-row suture anchor technique were compared to traditional transosseous suture techniques and control groups. The repaired tendons were loaded with 5 mm/min static velocity with 2.5 kgN load cell in Instron 8874 machine until the repair failure. The 1 cm transosseous group was statistically superior to 1 cm control group (p=0.021, p<0.05) and the 3 cm SpeedBridge group was statistically superior to the 1 cm SpeedFix group (p=0.012, p<0.05). The differences between the other groups were not statistically significant. No significant difference was found between the new knotless suture anchor techniques and traditional transosseous suture techniques.
Aksamija, Goran; Mulabdic, Adi; Rasic, Ismar; Muhovic, Samir; Gavric, Igor
2011-01-01
Polytrauma is defined as an injury where they are affected by at least two different organ systems or body, with at least one life-threatening injuries. Given the multilevel model care of polytrauma patients within KCUS are inevitable weaknesses in the management of this category of patients. To determine the dynamics of existing procedures in treatment of polytrauma patients on admission to KCUS, and based on statistical analysis of variables applied to determine and define the factors that influence the final outcome of treatment, and determine their mutual relationship, which may result in eliminating the flaws in the approach to the problem. The study was based on 263 polytrauma patients. Parametric and non-parametric statistical methods were used. Basic statistics were calculated, based on the calculated parameters for the final achievement of research objectives, multicoleration analysis, image analysis, discriminant analysis and multifactorial analysis were used. From the universe of variables for this study we selected sample of n = 25 variables, of which the first two modular, others belong to the common measurement space (n = 23) and in this paper defined as a system variable methods, procedures and assessments of polytrauma patients. After the multicoleration analysis, since the image analysis gave a reliable measurement results, we started the analysis of eigenvalues, that is defining the factors upon which they obtain information about the system solve the problem of the existing model and its correlation with treatment outcome. The study singled out the essential factors that determine the current organizational model of care, which may affect the treatment and better outcome of polytrauma patients. This analysis has shown the maximum correlative relationships between these practices and contributed to development guidelines that are defined by isolated factors.
Tavares, M; de Lima, C; Fernandes, W; Martinelli, V; de Lucena, M; Lima, F; Telles, A; Brandão, L; de Melo Júnior, M
2016-12-01
Inflammatory bowel disease consists of multifactorial diseases whose common manifestation is inflammation of the gastrointestinal tract and their pathogenesis remains unknown. This study aimed to analyse the gene polymorphisms in Brazilian patients with inflammatory bowel disease. A total of 101 patients diagnosed with inflammatory bowel disease were analysed for the tumour necrosis factor-alpha (-308 G/A; rs1800629) and interleukin-10 (-1082 G/A; rs1800896) gene polymorphisms. Genotyping was performed through polymerase chain reaction-sequence-specific primer, then fractionated on 2% agarose gel and visualized after staining by ethidium bromide. The anatomic-clinical form of Crohn's disease (CD) predominant was the inflammatory (32.75%), followed by fistulizing (29.31%) and 27.58% stricturing. As control group, a total of 136 healthy subjects, from the same geographical region, were enrolled. The statistical analyses were performed using R program. The frequency of the A allele at tumour necrosis factor-alpha was high in ulcerative colitis (UC) patients (51%) than in controls (22%; P > 0.01). No statistical difference was found with the genotypic and allelic frequencies of CD patients compared to controls (P = 0.54). The polymorphism -1082G/A of interleukin-10 was not statistical different between the diseases compared to controls. Tumour necrosis factor-alpha (TNF-α) (-308G/A) is associated with UC onset, suggesting that the presence of -308A allele could confer a relative risk of 3.62 more to develop UC in general population. Further studies, increasing the number of individuals, should be performed to ratify the role of TNF-α in the inflammatory bowel disease pathogenesis. © 2016 John Wiley & Sons Ltd.
Decaestecker, C; Lopes, B S; Gordower, L; Camby, I; Cras, P; Martin, J J; Kiss, R; VandenBerg, S R; Salmon, I
1997-04-01
The oligoastrocytoma, as a mixed glioma, represents a nosologic dilemma with respect to precisely defining the oligodendroglial and astroglial phenotypes that constitute the neoplastic cell lineages of these tumors. In this study, cell image analysis with Feulgen-stained nuclei was used to distinguish between oligodendroglial and astrocytic phenotypes in oligodendrogliomas and astrocytomas and then applied to mixed oligoastrocytomas. Quantitative features with respect to chromatin pattern (30 variables) and DNA ploidy (8 variables) were evaluated on Feulgen-stained nuclei in a series of 71 gliomas using computer-assisted microscopy. These included 32 oligodendrogliomas (OLG group: 24 grade II and 8 grade III tumors according to the WHO classification), 32 astrocytomas (AST group: 13 grade II and 19 grade III tumors), and 7 oligoastrocytomas (OLGAST group). Initially, image analysis with multivariate statistical analyses (Discriminant Analysis) could identify each glial tumor group. Highly significant statistical differences were obtained distinguishing the morphonuclear features of oligodendrogliomas from those of astrocytomas, regardless of their histological grade. When compared with the 7 mixed oligoastrocytomas under study, 5 exhibited DNA ploidy and chromatin pattern characteristics similar to grade II oligodendrogliomas, I to grade III oligodendrogliomas, and I to grade II astrocytomas. Using multifactorial statistical analyses (Discriminant Analysis combined with Principal Component Analysis). It was possible to quantify the proportion of "typical" glial cell phenotypes that compose grade II and III oligodendrogliomas and grade II and III astrocytomas in each mixed glioma. Cytometric image analysis may be an important adjunct to routine histopathology for the reproducible identification of neoplasms containing a mixture of oligodendroglial and astrocytic phenotypes.
Design of order statistics filters using feedforward neural networks
NASA Astrophysics Data System (ADS)
Maslennikova, Yu. S.; Bochkarev, V. V.
2016-08-01
In recent years significant progress have been made in the development of nonlinear data processing techniques. Such techniques are widely used in digital data filtering and image enhancement. Many of the most effective nonlinear filters based on order statistics. The widely used median filter is the best known order statistic filter. Generalized form of these filters could be presented based on Lloyd's statistics. Filters based on order statistics have excellent robustness properties in the presence of impulsive noise. In this paper, we present special approach for synthesis of order statistics filters using artificial neural networks. Optimal Lloyd's statistics are used for selecting of initial weights for the neural network. Adaptive properties of neural networks provide opportunities to optimize order statistics filters for data with asymmetric distribution function. Different examples demonstrate the properties and performance of presented approach.
Statistical evaluation of vibration analysis techniques
NASA Technical Reports Server (NTRS)
Milner, G. Martin; Miller, Patrice S.
1987-01-01
An evaluation methodology is presented for a selection of candidate vibration analysis techniques applicable to machinery representative of the environmental control and life support system of advanced spacecraft; illustrative results are given. Attention is given to the statistical analysis of small sample experiments, the quantification of detection performance for diverse techniques through the computation of probability of detection versus probability of false alarm, and the quantification of diagnostic performance.
1985-09-01
TECHNIQUES THESIS Robert A. Heinlein Captain, USAF AFIT/GLM/LSM/855-32.- _ DTIC MU’noN ’ST.,TEMENT A A-ZELECTE Approved lt public teleo*I Al \\ Z #&N0V21...343" A FEASIBILITY STUDY OF THE COLLECTION OF UNSCHEDULED MAINTENANCE DATA USING STrATISTICAL SAMPLING TECHNIQUES THESIS L .9 Robe-t A. Heinlein...a AFIT/GLM/LSM/85S-32 A FEASIBILITY STUDY OF THE COLLECTION OF UNSCHEDULED MAINTENANCE DATA USING STATISTICAL SAMPLING TECHNIQUES THESIS
The Epigenetic Landscape of Alcoholism
Krishnan, Harish R.; Sakharkar, Amul J.; Teppen, Tara L.; Berkel, Tiffani D.M.; Pandey, Subhash C.
2015-01-01
Alcoholism is a complex psychiatric disorder that has a multifactorial etiology. Epigenetic mechanisms are uniquely capable of accounting for the multifactorial nature of the disease in that they are highly stable and are affected by environmental factors, including alcohol itself. Chromatin remodeling causes changes in gene expression in specific brain regions contributing to the endophenotypes of alcoholism such as tolerance and dependence. The epigenetic mechanisms that regulate changes in gene expression observed in addictive behaviors respond not only to alcohol exposure, but also to comorbid psychopathology such as the presence of anxiety and stress. This review summarizes recent developments in epigenetic research that may play a role in alcoholism. We propose that pharmacologically manipulating epigenetic targets, as demonstrated in various preclinical models, holds great therapeutic potential in the treatment and prevention of alcoholism. PMID:25131543
Kamala, K A; Sankethguddad, S; Sujith, S G; Tantradi, Praveena
2016-01-01
Burning mouth syndrome (BMS) is multifactorial in origin which is typically characterized by burning and painful sensation in an oral cavity demonstrating clinically normal mucosa. Although the cause of BMS is not known, a complex association of biological and psychological factors has been identified, suggesting the existence of a multifactorial etiology. As the symptom of oral burning is seen in various pathological conditions, it is essential for a clinician to be aware of how to differentiate between symptom of oral burning and BMS. An interdisciplinary and systematic approach is required for better patient management. The purpose of this study was to provide the practitioner with an understanding of the local, systemic, and psychosocial factors which may be responsible for oral burning associated with BMS, and review of treatment modalities, therefore providing a foundation for diagnosis and treatment of BMS.
Biological adaptive control model: a mechanical analogue of multi-factorial bone density adaptation.
Davidson, Peter L; Milburn, Peter D; Wilson, Barry D
2004-03-21
The mechanism of how bone adapts to every day demands needs to be better understood to gain insight into situations in which the musculoskeletal system is perturbed. This paper offers a novel multi-factorial mathematical model of bone density adaptation which combines previous single-factor models in a single adaptation system as a means of gaining this insight. Unique aspects of the model include provision for interaction between factors and an estimation of the relative contribution of each factor. This interacting system is considered analogous to a Newtonian mechanical system and the governing response equation is derived as a linear version of the adaptation process. The transient solution to sudden environmental change is found to be exponential or oscillatory depending on the balance between cellular activation and deactivation frequencies.
HUGO urges genetic benefit-sharing.
2000-01-01
In view of the fact that for-profit enterprise exceeds public expenditures on genetic research and that benefits from the Human Genome Project may accrue only to rich people in rich nations, the HUGO Ethics Committee discussed the necessity of benefit-sharing. Discussions involved case examples ranging from single-gene to multi-factorial disorders and included the difficulties of defining community, especially when multifactorial diseases are involved. The Committee discussed arguments for benefit-sharing, including common heritage, the genome as a common resource, and three types of justice: compensatory, procedural, and distributive. The Committee also discussed the importance of community participation in defining benefit, agreed that companies involved in health have special obligations beyond paying taxes, and recommended they devote 1-3% of net profits to healthcare infrastructure or humanitarian efforts.
NASA Astrophysics Data System (ADS)
Zan, Tao; Wang, Min; Hu, Jianzhong
2010-12-01
Machining status monitoring technique by multi-sensors can acquire and analyze the machining process information to implement abnormity diagnosis and fault warning. Statistical quality control technique is normally used to distinguish abnormal fluctuations from normal fluctuations through statistical method. In this paper by comparing the advantages and disadvantages of the two methods, the necessity and feasibility of integration and fusion is introduced. Then an approach that integrates multi-sensors status monitoring and statistical process control based on artificial intelligent technique, internet technique and database technique is brought forward. Based on virtual instrument technique the author developed the machining quality assurance system - MoniSysOnline, which has been used to monitoring the grinding machining process. By analyzing the quality data and AE signal information of wheel dressing process the reason of machining quality fluctuation has been obtained. The experiment result indicates that the approach is suitable for the status monitoring and analyzing of machining process.
39 CFR 3050.1 - Definitions applicable to this part.
Code of Federal Regulations, 2010 CFR
2010-07-01
..., mathematical, or statistical theory, precept, or assumption applied by the Postal Service in producing a... manipulation technique whose validity does not require the acceptance of a particular economic, mathematical, or statistical theory, precept, or assumption. A change in quantification technique should not change...
A Study on Predictive Analytics Application to Ship Machinery Maintenance
2013-09-01
Looking at the nature of the time series forecasting method , it would be better applied to offline analysis . The application for real- time online...other system attributes in future. Two techniques of statistical analysis , mainly time series models and cumulative sum control charts, are discussed in...statistical tool employed for the two techniques of statistical analysis . Both time series forecasting as well as CUSUM control charts are shown to be
Methods for trend analysis: Examples with problem/failure data
NASA Technical Reports Server (NTRS)
Church, Curtis K.
1989-01-01
Statistics are emphasized as an important role in quality control and reliability. Consequently, Trend Analysis Techniques recommended a variety of statistical methodologies that could be applied to time series data. The major goal of the working handbook, using data from the MSFC Problem Assessment System, is to illustrate some of the techniques in the NASA standard, some different techniques, and to notice patterns of data. Techniques for trend estimation used are: regression (exponential, power, reciprocal, straight line) and Kendall's rank correlation coefficient. The important details of a statistical strategy for estimating a trend component are covered in the examples. However, careful analysis and interpretation is necessary because of small samples and frequent zero problem reports in a given time period. Further investigations to deal with these issues are being conducted.
Retardation in Mathematics: A Consideration of Multi-Factorial Determination
ERIC Educational Resources Information Center
Lansdown, Richard
1978-01-01
Discusses mathematical retardation as a construct and examines the possible contributions of emotional factors, socioeconomic factors, poor teaching, cognitive factors, and sex difference to low achievement in mathematics. (JB)
Gæde, Peter; Oellgaard, Jens; Carstensen, Bendix; Rossing, Peter; Lund-Andersen, Henrik; Parving, Hans-Henrik; Pedersen, Oluf
2016-11-01
The aim of this work was to study the potential long-term impact of a 7.8 years intensified, multifactorial intervention in patients with type 2 diabetes mellitus and microalbuminuria in terms of gained years of life and years free from incident cardiovascular disease. The original intervention (mean treatment duration 7.8 years) involved 160 patients with type 2 diabetes and microalbuminuria who were randomly assigned (using sealed envelopes) to receive either conventional therapy or intensified, multifactorial treatment including both behavioural and pharmacological approaches. After 7.8 years the study continued as an observational follow-up with all patients receiving treatment as for the original intensive-therapy group. The primary endpoint of this follow-up 21.2 years after intervention start was difference in median survival time between the original treatment groups with and without incident cardiovascular disease. Non-fatal endpoints and causes of death were adjudicated by an external endpoint committee blinded for treatment allocation. Thirty-eight intensive-therapy patients vs 55 conventional-therapy patients died during follow-up (HR 0.55 [95% CI 0.36, 0.83], p = 0.005). The patients in the intensive-therapy group survived for a median of 7.9 years longer than the conventional-therapy group patients. Median time before first cardiovascular event after randomisation was 8.1 years longer in the intensive-therapy group (p = 0.001). The hazard for all microvascular complications was decreased in the intensive-therapy group in the range 0.52 to 0.67, except for peripheral neuropathy (HR 1.12). At 21.2 years of follow-up of 7.8 years of intensified, multifactorial, target-driven treatment of type 2 diabetes with microalbuminuria, we demonstrate a median of 7.9 years of gain of life. The increase in lifespan is matched by time free from incident cardiovascular disease. ClinicalTrials.gov registration no. NCT00320008. The study was funded by an unrestricted grant from Novo Nordisk A/S.
Willeboordse, Maartje; van de Kant, Kim D G; de Laat, Maroeska N; van Schayck, Onno C P; Mulkens, Sandra; Dompeling, Edward
2013-05-21
In children, the prevalence's of both obesity and asthma are disconcertingly high. Asthmatic children with obesity are characterised by less asthma control and a high need for asthma medication. As the obese asthmatic child is becoming more common in the clinical setting and the disease burden of the asthma-obesity phenotype is high, there is an increasing need for effective treatment in these children. In adults, weight reduction resulted in improved lung function, better asthma control and less need for asthma medication. In children this is hardly studied. The Mikado study aims to evaluate the effectiveness of a long term multifactorial weight reduction intervention, on asthma characteristics in children with asthma and a high body weight. The Mikado study is a two-armed, randomised controlled trial. In total, 104 participants will be recruited via online questionnaires, pulmonary paediatricians, the youth department of the Municipal Health Services and cohorts of existing studies. All participants will be aged 6-16 years, will have current asthma, a Body Mass Index in the overweight or obesity range, and no serious comorbidities (such as diabetes, heart diseases). Participants in the intervention arm will receive a multifactorial intervention of 18 months consisting of sessions concerning sports, parental involvement, individual counselling and lifestyle advices including dietary advices and cognitive behavioural therapy. The control group will receive usual care. The primary outcome variables will include Forced Expiratory Volume in one second and Body Mass Index - Standard Deviation Score. Secondary outcomes will include other lung function parameters (including dynamic and static lung function parameters), asthma control, asthma-specific quality of life, use of asthma medication and markers of systemic inflammation and airway inflammation. In this randomised controlled trial we will study the potential of a multifactorial weight reduction intervention to improve asthma-related outcome measures in asthmatic children with overweight. Moreover, it will provide information about the underlying mechanisms in the relationship between asthma and a high body weight in children. These findings can contribute to optimal management programs and better clinical guidelines for children with asthma and overweight. Clinicaltrial.gov NCT00998413.
Lee, Hsuei-Chen; Chang, Ku-Chou; Tsauo, Jau-Yih; Hung, Jen-Wen; Huang, Yu-Ching; Lin, Sang-I
2013-04-01
To evaluate effects of a multifactorial fall prevention program on fall incidence and physical function in community-dwelling older adults. Multicenter randomized controlled trial. Three medical centers and adjacent community health centers. Community-dwelling older adults (N=616) who have fallen in the previous year or are at risk of falling. After baseline assessment, eligible subjects were randomly allocated into the intervention group (IG) or the control group (CG), stratified by the Physiological Profile Assessment (PPA) fall risk level. The IG received a 3-month multifactorial intervention program including 8 weeks of exercise training, health education, home hazards evaluation/modification, along with medication review and ophthalmology/other specialty consults. The CG received health education brochures, referrals, and recommendations without direct exercise intervention. Primary outcome was fall incidence within 1 year. Secondary outcomes were PPA battery (overall fall risk index, vision, muscular strength, reaction time, balance, and proprioception), Timed Up & Go (TUG) test, Taiwan version of the International Physical Activity Questionnaire, EuroQol-5D, Geriatric Depression Scale (GDS), and the Falls Efficacy Scale-International at 3 months after randomization. Participants were 76±7 years old and included low risk 25.6%, moderate risk 25.6%, and marked risk 48.7%. The cumulative 1-year fall incidence was 25.2% in the IG and 27.6% in the CG (hazard ratio=.90; 95% confidence interval, .66-1.23). The IG improved more favorably than the CG on overall PPA fall risk index, reaction time, postural sway with eyes open, TUG test, and GDS, especially for those with marked fall risk. The multifactorial fall prevention program with exercise intervention improved functional performance at 3 months for community-dwelling older adults with risk of falls, but did not reduce falls at 1-year follow-up. Fall incidence might have been decreased simultaneously in both groups by heightened awareness engendered during assessments, education, referrals, and recommendations. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
Secondary Analysis of Qualitative Data.
ERIC Educational Resources Information Center
Turner, Paul D.
The reanalysis of data to answer the original research question with better statistical techniques or to answer new questions with old data is not uncommon in quantitative studies. Meta analysis and research syntheses have increased with the increase in research using similar statistical analyses, refinements of analytical techniques, and the…
Computer program uses Monte Carlo techniques for statistical system performance analysis
NASA Technical Reports Server (NTRS)
Wohl, D. P.
1967-01-01
Computer program with Monte Carlo sampling techniques determines the effect of a component part of a unit upon the overall system performance. It utilizes the full statistics of the disturbances and misalignments of each component to provide unbiased results through simulated random sampling.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gilbert, Richard O.
The application of statistics to environmental pollution monitoring studies requires a knowledge of statistical analysis methods particularly well suited to pollution data. This book fills that need by providing sampling plans, statistical tests, parameter estimation procedure techniques, and references to pertinent publications. Most of the statistical techniques are relatively simple, and examples, exercises, and case studies are provided to illustrate procedures. The book is logically divided into three parts. Chapters 1, 2, and 3 are introductory chapters. Chapters 4 through 10 discuss field sampling designs and Chapters 11 through 18 deal with a broad range of statistical analysis procedures. Somemore » statistical techniques given here are not commonly seen in statistics book. For example, see methods for handling correlated data (Sections 4.5 and 11.12), for detecting hot spots (Chapter 10), and for estimating a confidence interval for the mean of a lognormal distribution (Section 13.2). Also, Appendix B lists a computer code that estimates and tests for trends over time at one or more monitoring stations using nonparametric methods (Chapters 16 and 17). Unfortunately, some important topics could not be included because of their complexity and the need to limit the length of the book. For example, only brief mention could be made of time series analysis using Box-Jenkins methods and of kriging techniques for estimating spatial and spatial-time patterns of pollution, although multiple references on these topics are provided. Also, no discussion of methods for assessing risks from environmental pollution could be included.« less
[Efficacy and safety of initial treatment with glimpeiride versus sitagliptin in type 2 diabetes].
Tamez-Pérez, Héctor Eloy
2015-01-01
Diabetes mellitus type 2 (DM2) is a multifactorial disease that can be treated with oral antiglycemic medication or with insulin. The antiglycemic drugs glimepiride and sitagliptin have different mechanisms of action, and have not been directly compared in a Latin-American population with recent DM2 diagnostic. The primary objective in this randomized (1:1), multicentric, two arms, open study with adult patients, was to compare the efficacy of glimepiride with sitagliptin in a DM2 population naïve to treatment. Secondary objectives had been the effect on fasting and postprandial glycemia, hypoglycemia, weight modification, safety, percentage of patients quiting the trial, vital signs and laboratory results. Glimepiride and sitagliptin were equally effective in glycemic control and all other parameters, and the only difference found has been the frequency of hypoglycemic events reports, wich has been reported as higher and statistically significant in the in the glimepiride group. No fatalities where reported in either group. Glimepiride or sitagliptin monotherapy are equally effective in control of HbA1c.
Klein, Kelly R.; Burkle Jr., Frederick M.; Swienton, Raymond; King, Richard V.; Lehman, Thomas; North, Carol S.
2016-01-01
Introduction: After all large-scale disasters multiple papers are published describing the shortcomings of the triage methods utilized. This paper uses medical provider input to help describe attributes and patient characteristics that impact triage decisions. Methods: A survey distributed electronically to medical providers with and without disaster experience. Questions asked included what disaster experiences they had, and to rank six attributes in order of importance regarding triage. Results: 403 unique completed surveys were analyzed. 92% practiced a structural triage approach with the rest reporting they used “gestalt”.(gut feeling) Twelve per cent were identified as having placed patients in an expectant category during triage. Respiratory status, ability to speak, perfusion/pulse were all ranked in the top three. Gut feeling regardless of statistical analysis was fourth. Supplies were ranked in the top four when analyzed for those who had placed patients in the expectant category. Conclusion: Primary triage decisions in a mass casualty scenario are multifactorial and encompass patient mobility, life saving interventions, situational instincts, and logistics. PMID:27651979
Pannullo, Francesca; Lee, Duncan; Waclawski, Eugene; Leyland, Alastair H
2016-08-01
The long-term impact of air pollution on human health can be estimated from small-area ecological studies in which the health outcome is regressed against air pollution concentrations and other covariates, such as socio-economic deprivation. Socio-economic deprivation is multi-factorial and difficult to measure, and includes aspects of income, education, and housing as well as others. However, these variables are potentially highly correlated, meaning one can either create an overall deprivation index, or use the individual characteristics, which can result in a variety of pollution-health effects. Other aspects of model choice may affect the pollution-health estimate, such as the estimation of pollution, and spatial autocorrelation model. Therefore, we propose a Bayesian model averaging approach to combine the results from multiple statistical models to produce a more robust representation of the overall pollution-health effect. We investigate the relationship between nitrogen dioxide concentrations and cardio-respiratory mortality in West Central Scotland between 2006 and 2012. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.
Role of muscarinic receptor antagonists in urgency and nocturia.
Michel, Martin C; de la Rosette, Jean J M C H
2005-09-01
The overactive bladder (OAB) syndrome is defined as urgency, with or without urgency incontinence, usually accompanied by frequency and nocturia. Muscarinic receptor antagonists are the most established form of treatment for OAB, but until recently their effectiveness was only confirmed for symptoms of incontinence and frequency. In recent studies, selected muscarinic antagonists, including darifenacin, solifenacin, tolterodine and trospium, significantly reduced the number of urgency episodes per day relative to placebo. While some data raise the possibility that certain of these agents may be more effective than others in this regard, this variability in their effect on urgency needs to be confirmed in future studies. Moreover, it remains to be determined whether counting the number of urgency episodes or assessing the subjective intensity of the sensation of urgency more adequately reflects patient needs and therapeutic efficacy. For nocturia, muscarinic receptor antagonists have only inconsistently shown statistically greater effects than placebo. This inconsistency may relate to the multifactorial nature of nocturia, which even in patients with OAB can have many causes, not all of which may respond/be sensitive to muscarinic receptor antagonism.
The measurement of serum TNF-α levels in patients with lichen planus.
Akpinar Kara, Yesim
2017-12-01
Lichen planus is a common mucocutaneous inflammatory skin disease with a multifactorial etiology. Cytokines play a key role in lichen planus pathogenesis. This study investigates the relationship between disease severity and levels of tumor necrosis factor-α (TNF-α), which is considered a primary cytokine that initiates cytotoxicity. Serum TNF-α levels were compared between a patient group (n = 34) and a control group (n = 20). TNF-α serum levels were measured using human TNF-α Enzyme-Linked Immunosorbent Assay (ELISA) test kits, and the two groups were statistically compared to each other. Mean serum TNF-α levels were found to be significantly higher in the patient group than in the control group (p < 0.005). However, no significant association was observed between TNF-α levels and oral mucosal involvement (p > 0.005). No relationship was detected between TNF-α levels and patients' sex. It is thought that TNF-α, a proinflammatory cytokine, may play an important role in the pathogenesis of lichen planus. TNF-α may be a simple and effective predictor to illustrate the inflammatory status in patients with lichen planus.
Factors that influence the tribocharging of pulverulent materials in compressed-air devices
NASA Astrophysics Data System (ADS)
Das, S.; Medles, K.; Mihalcioiu, A.; Beleca, R.; Dragan, C.; Dascalescu, L.
2008-12-01
Tribocharging of pulverulent materials in compressed-air devices is a typical multi-factorial process. This paper aims at demonstrating the interest of using the design of experiments methodology in association with virtual instrumentation for quantifying the effects of various process varaibles and of their interactions, as a prerequisite for the development of new tribocharging devices for industrial applications. The study is focused on the tribocharging of PVC powders in compressed-air devices similar to those employed in electrostatic painting. A classical 2 full-factorial design (3 factors at two levels) was employed for conducting the experiments. The response function was the charge/mass ratio of the material collected in a modified Faraday cage, at the exit of the tribocharging device. The charge/mass ratio was found to increase with the injection pressure and the vortex pressure in the tribocharging device, and to decrease with the increasing of the feed rate. In the present study an in-house design of experiments software was employed for statistical analysis of experimental data and validation of the experimental model.
Assessment of anxiety and depression in patients with burning mouth syndrome: A clinical trial
Malik, Rohit; Goel, Sumit; Misra, Deepankar; Panjwani, Sapna; Misra, Akansha
2012-01-01
Introduction: Burning mouth syndrome is a chronic pain syndrome primarily affecting elderly women with hormonal changes or psychological disorders. It is multifactorial in origin, often idiopathic and its etiopathogenesis, majorly being neuropathic, largely remains enigmatic. Aim: To determine the prevalence of burning mouth symptom, in elderly women and evaluate local and systemic causes responsible for burning sensation. Materials and Methods: 100 elderly postmenopausal women were included in the study out of which 56 had a chief complaint of burning sensation. These patients were evaluated for the levels of anxiety and depression by means of questionnaire. The severity of burning and the response to the treatment was assessed with a five point Visual Analog Scale. The results were analyzed using “Chi-square test”. Results: There was statistically significant increase in the levels of anxiety and depression in the study group. Conclusion: The present study clearly indicates that most of the patients had moderate to severe levels of depression, which suggests that anxiety and depression are constant features in postmenopausal female patients. PMID:22923978
Duval, Florian; Leroux, Agathe; Bertaud, Valérie; Meary, Fleur; Le Padellec, Clément; Refuveille, Laura; Lemaire, Arnaud; Sorel, Olivier; Chauvel-Lebret, Dominique
2015-09-01
The aim of this study was to assess the impact of extraction of third molars on the occurrence of temporo-mandibular disorders (TMD). A review of the literature and a case-control study have been conducted. The case-control study compares the frequency of extraction of third molars between the sample with TMD (case) and the sample without TMD (control). The proportion of patients who had undergone extractions of wisdom teeth was higher in the case group than in the control group. The difference was statistically significant when patients had undergone extraction of all four wisdom teeth or when the extraction of four wisdom teeth underwent in one sitting or under general anesthesia. The study of patients in case sample shows that all signs of TMD were more common in patients who had undergone extractions in several sessions and under local anesthesia. The temporomandibular joint sounds are significantly more frequent with local anesthesia. In the case group, 85 to 92% of patients have parafunctions and 5 to 11% have malocclusion. This demonstrates the multifactorial etiology of temporomandibular disorders. © EDP Sciences, SFODF, 2015.
Immunotherapy for recurrent malignant glioma: an interim report on survival.
Ingram, M; Buckwalter, J G; Jacques, D B; Freshwater, D B; Abts, R M; Techy, G B; Miyagi, K; Shelden, C H; Rand, R W; English, L W
1990-12-01
We present interim survival data for a group of 83 adult patients with recurrent malignant glioma treated by implanting stimulated autologous lymphocytes into the tumour bed following surgical debulking. The patients were treated 6 months or more prior to data analysis. Fifty-nine patients were male and 24 female. The mean age for the entire group was 48.4 years and the mean Karnofsky rating (KR) was 67.2. Eight of the patients had grade II tumours, 33 had grade III tumours and 42 had grade IV tumours. Statistical analysis focuses on tumour grade, KR and patient age, factors that have been shown to affect survival in previous studies. Multifactorial analyses are employed to identify interrelationships among factors related to survival. Seven patients (8%) did not respond to immunotherapy, 76 (92%) had a good initial response. Twenty-five patients (30.1%) are living and 18 (22%) have shown no evidence of recurrence. Results are evaluated in the light of those obtained in trials of other experimental therapies for recurrent malignant gliomas. It is concluded that the present protocol offers a safe and comparatively effective treatment option.
[Etiopathogenesis and treatment of breast capsular contracture].
Pereira Leite, Luis; Correia Sá, Inês; Marques, Marisa
2013-01-01
Capsular contracture is a chronic and the most frequent complication of augmentation mammoplasty with breast implants and the main cause of patient's and surgeon's dissatisfaction. The mammary capsule consists of a fibrous tissue that surrounds the implant that may contract, changing the shape and consistency of the breast. In its advanced stage is accompanied by pronounced deformity, hardness and pain, being indicated for surgical treatment. All the articles indexed on PubMed through the search 'capsular contracture' (2000 - January 2012) were reviewed and were included the articles of greater interest in terms of etiology, prophylaxis and treatment. Articles referred in relevant publications were also examined. Everything indicates that its etiology is multifactorial; the etiopathology of breast capsular contracture continues being subject of multiple pre-clinical investigations. There are many studies performed in order to prevent the onset of capsular contracture but, although promising results, little is set for its application on clinical practice. The capsulectomy/capsulotomy continues being the gold standard treatment although the future may undergo non invasive techniques, at least in mild stages of disease. Although the surgical techniques and the quality of breast implants have been improving drastically in recent years, capsular contracture remains a real complication with great incidence and that continues affecting thousands of women all over the world.
Patellofemoral Arthroplasty: Current Concepts and Review of the Literature
Pisanu, Gabriele; Rosso, Federica; Bertolo, Corrado; Dettoni, Federico; Blonna, Davide; Bonasia, Davide Edoardo; Rossi, Roberto
2017-01-01
Patellofemoral osteoarthritis (PFOA) can be associated with anterior knee pain, stiffness, and functional impairment. Some authors report that PFOA affects approximately 9% of patients older than 40 years with a greater prevalence in females. Etiology of PFOA is multifactorial and is related to the presence of abnormal stresses at the PF joint due to knee- and patient-related factors. The need for a joint preserving treatment by isolated replacement of the injured compartment of the knee led to the development of PF arthroplasty (PFA). When a correct PF replacement is performed, PFA preserves physiologic tibiofemoral joint, thus allowing patients for a rapid recovery with a high satisfaction. The outcomes for PFA are quite variable with a trend toward good to excellent results, mainly owing to the improvement in surgical techniques, patient selection, and implant design. The development of the second generation of PFA improved the outcomes, which is attributed to the different trochlear designs. Recently, encouraging results have been provided by the association of PFA and unicompartmental knee arthroplasty (UKA). In many studies, the main cause of PFA failure is progression of tibiofemoral OA. The aim of this brief review of literature is to summarize the clinical features, indications and contraindications, surgical techniques, complications, and outcomes of PFA. PMID:29270562
Tameem, Hussain Z.; Sinha, Usha S.
2011-01-01
Osteoarthritis (OA) is a heterogeneous and multi-factorial disease characterized by the progressive loss of articular cartilage. Magnetic Resonance Imaging has been established as an accurate technique to assess cartilage damage through both cartilage morphology (volume and thickness) and cartilage water mobility (Spin-lattice relaxation, T2). The Osteoarthritis Initiative, OAI, is a large scale serial assessment of subjects at different stages of OA including those with pre-clinical symptoms. The electronic availability of the comprehensive data collected as part of the initiative provides an unprecedented opportunity to discover new relationships in complex diseases such as OA. However, imaging data, which provides the most accurate non-invasive assessment of OA, is not directly amenable for data mining. Changes in morphometry and relaxivity with OA disease are both complex and subtle, making manual methods extremely difficult. This chapter focuses on the image analysis techniques to automatically localize the differences in morphometry and relaxivity changes in different population sub-groups (normal and OA subjects segregated by age, gender, and race). The image analysis infrastructure will enable automatic extraction of cartilage features at the voxel level; the ultimate goal is to integrate this infrastructure to discover relationships between the image findings and other clinical features. PMID:21785520
Dental radiographic indicators, a key to age estimation
Panchbhai, AS
2011-01-01
Objective The present review article is aimed at describing the radiological methods utilized for human age identification. Methods The application and importance of radiological methods in human age assessment was discussed through the literature survey. Results Following a literature search, 46 articles were included in the study and the relevant information is depicted in the article. Dental tissue is often preserved indefinitely after death. Implementation of radiography is based on the assessment of the extent of calcification of teeth and in turn the degree of formation of crown and root structures, along with the sequence and the stages of eruption. Several radiological techniques can be used to assist in both individual and general identification, including determination of gender, ethnic group and age. The radiographic method is a simpler and cheaper method of age identification compared with histological and biochemical methods. Radiographic and tomographic images have become an essential aid for human identification in forensic dentistry, particularly with the refinement of techniques and the incorporation of information technology resources. Conclusion Based on an appropriate knowledge of the available methods, forensic dentists can choose the most appropriate since the validity of age estimation crucially depends on the method used and its proper application. The multifactorial approach will lead to optimum age assessment. The legal requirements also have to be considered. PMID:21493876
Life course perspectives on the epidemiology of depression.
Colman, Ian; Ataullahjan, Anushka
2010-10-01
Life course epidemiology seeks to understand how determinants of health and disease interact across the span of a human life, and has made significant contributions to understanding etiological mechanisms in many chronic diseases, including schizophrenia. The life course approach is ideal for understanding depression: causation in depression appears to be multifactorial, including interactions between genes and stressful events, or between early life trauma and later stress in life; timing of onset and remission of depression varies widely, indicating differing trajectories of symptoms over long periods of time, with possible differing causes and differing outcomes; and early life events and development appear to be important risk factors for depression, including exposure to acute and chronic stress in the first years of life. To better understand etiology and outcome of depression, future research must move beyond basic epidemiologic techniques that link specific exposures to specific outcomes and embrace life course principles and methods. Time-sensitive modelling techniques that are able to incorporate multiple interacting factors across long periods of time, such as structural equation models, will be critical in understanding the complexity of causal and influencing factors from early development to the end stages of life. Using these models to identify key pathways that influence trajectories of depression across the life course will help guide prevention and intervention.
NASA Astrophysics Data System (ADS)
Tameem, Hussain Z.; Sinha, Usha S.
2007-11-01
Osteoarthritis (OA) is a heterogeneous and multi-factorial disease characterized by the progressive loss of articular cartilage. Magnetic Resonance Imaging has been established as an accurate technique to assess cartilage damage through both cartilage morphology (volume and thickness) and cartilage water mobility (Spin-lattice relaxation, T2). The Osteoarthritis Initiative, OAI, is a large scale serial assessment of subjects at different stages of OA including those with pre-clinical symptoms. The electronic availability of the comprehensive data collected as part of the initiative provides an unprecedented opportunity to discover new relationships in complex diseases such as OA. However, imaging data, which provides the most accurate non-invasive assessment of OA, is not directly amenable for data mining. Changes in morphometry and relaxivity with OA disease are both complex and subtle, making manual methods extremely difficult. This chapter focuses on the image analysis techniques to automatically localize the differences in morphometry and relaxivity changes in different population sub-groups (normal and OA subjects segregated by age, gender, and race). The image analysis infrastructure will enable automatic extraction of cartilage features at the voxel level; the ultimate goal is to integrate this infrastructure to discover relationships between the image findings and other clinical features.
Interleukin-18 -607C/A gene polymorphism in Egyptian asthmatic children.
Shaaban, Hala Hamdi; Mohy, Abeer Mohamed; Abdel-Razek, Abdel-Rahman Ahmed; Wahab, Amira Abdel
2014-08-01
Asthma is a multifactorial respiratory disease determined by interactions of multiple disease susceptibility genes and environmental factors. Interleukin (IL)-18 is an important cytokine for initiating and perpetuating the catabolic and inflammatory response in allergic asthma. A number of single nucleotide polymorphisms that influence IL-18 production are found in the gene promoter region. The aim of this study was to investigate the association of IL-18 -607C/A promoter polymorphism with asthma and whether this polymorphism influenced the severity of asthma in affected children. The influence of this promoter gene polymorphism on total serum IgE level in studied subjects was also investigated. This study was carried out at the Allergy Clinic of Abu El Reesh Children's Hospital at Cairo University, Egypt. This study included 40 asthmatic children, subdivided into four groups according to different degrees of asthma severity, and 20 apparently healthy subjects as the control group. All cases were subjected to history taking, clinical examination, and the following laboratory investigations: complete blood count, total serum IgE level assay by ELISA and genomic DNA extraction, and analysis for IL-18 -607C/A promoter gene polymorphism using the PCR-RFLP (restriction fragment length polymorphism) technique. In the present study the IL-18 -607AA genotype frequency was higher in cases (22.5 %) than in the control group (15 %); however, the difference was not statistically significant (p = 0.773). No statistically significant difference between the degree of asthma severity and IL-18 -607C/A polymorphism was found (p = 0.489). No significant association could be detected upon comparing the frequencies of C and A alleles among the two studied groups (p = 0.366). Also, no significant differences were demonstrated for the allele frequencies when the intermittent with mild [odds ratio (OR) = 2.72, 95 % CI 1.03-2.33, p = 0.067], intermittent with moderate, and severe (OR = 2.8, 95 % CI 1.01-8.5, p = 0.066) asthma groups were compared. The median value of the total serum IgE level in asthmatic cases with the mutant genotype (AA) was significantly higher [360 IU/L (96.6-1,340 IU/L)] than in the control group [119 IU/L (70.6-158.9 IU/L)] (p = 0.033). No significant statistical difference was encountered regarding the distribution of IL-18 -607C/A genotypes and allele frequencies in asthma patients and healthy controls. Also, there were no significant associations between asthma severity and different genotypes or alleles. The median value of the total serum IgE level in asthmatic cases with the mutant genotype (AA) was significantly higher than in the control group. Thus, IL-18 -607AA genotype frequency might be related to higher total serum IgE.
Medication fall risk in old hospitalized patients: a retrospective study.
Costa-Dias, Maria José; Oliveira, Alexandre Santos; Martins, Teresa; Araújo, Fátima; Santos, Ana Sofia; Moreira, Cristina Nogueira; José, Helena
2014-02-01
While the causes of falls in old hospitalized patients are multifactorial, medication has been considered as one of the most significant factors. Given the large impact that this phenomenon has on the lives of the elderly and organizations, it is important to explore such phenomenon in greater depth. The objective of this study was to explore the association between medication and falls and the recurrent falls (n≥2), and identify medication related risk for fall in hospitalized patients, in a large acute hospital. Retrospective and quantitative study from June 2008 to December 2010. The study was conducted in a private hospital for acute patients in Lisbon, Portugal. The study included a sample of 214 episodes of fall event notifications which occurred in 193 patients. The current study was conducted through the "face to face consensus" technique which emerged the treatment groups to investigate. Regarding the data analysis we used Student's t test, ANOVA and Odds Ratio. In the violation of the premises for the use of parametric statistics we used the Kruskal-Wallis test. To assess the fall risk, and the medication-related fall risk, we used the Morse Fall Risk Scale, and the Medication Fall Risk Score. Patients who received drugs from the therapy group of "Central Nervous System", are 10 times more likely to have fall risk (OR 9. 90, 95% CI 1.6-60.63). Association was found between falls (OR 6.09, 95% CI 1.30-28.54) and its recurrence (OR 3.32, 95% CI 1.61-6.85), among patients receiving haloperidol and receiving tramadol for recurrent falls (OR 3.10, 95% CI 1.59-6.07). In 34% of the patients the medication fall risk score was 6 or higher. This current study allowed identifying medication-related risk factors for falls, that nurses should consider when prescribing interventions to prevent falls and its recurrence, when patients are admitted to acute care hospitals. Copyright © 2014 Elsevier Ltd. All rights reserved.
Statistical reconstruction for cosmic ray muon tomography.
Schultz, Larry J; Blanpied, Gary S; Borozdin, Konstantin N; Fraser, Andrew M; Hengartner, Nicolas W; Klimenko, Alexei V; Morris, Christopher L; Orum, Chris; Sossong, Michael J
2007-08-01
Highly penetrating cosmic ray muons constantly shower the earth at a rate of about 1 muon per cm2 per minute. We have developed a technique which exploits the multiple Coulomb scattering of these particles to perform nondestructive inspection without the use of artificial radiation. In prior work [1]-[3], we have described heuristic methods for processing muon data to create reconstructed images. In this paper, we present a maximum likelihood/expectation maximization tomographic reconstruction algorithm designed for the technique. This algorithm borrows much from techniques used in medical imaging, particularly emission tomography, but the statistics of muon scattering dictates differences. We describe the statistical model for multiple scattering, derive the reconstruction algorithm, and present simulated examples. We also propose methods to improve the robustness of the algorithm to experimental errors and events departing from the statistical model.
Technique for estimation of streamflow statistics in mineral areas of interest in Afghanistan
Olson, Scott A.; Mack, Thomas J.
2011-01-01
A technique for estimating streamflow statistics at ungaged stream sites in areas of mineral interest in Afghanistan using drainage-area-ratio relations of historical streamflow data was developed and is documented in this report. The technique can be used to estimate the following streamflow statistics at ungaged sites: (1) 7-day low flow with a 10-year recurrence interval, (2) 7-day low flow with a 2-year recurrence interval, (3) daily mean streamflow exceeded 90 percent of the time, (4) daily mean streamflow exceeded 80 percent of the time, (5) mean monthly streamflow for each month of the year, (6) mean annual streamflow, and (7) minimum monthly streamflow for each month of the year. Because they are based on limited historical data, the estimates of streamflow statistics at ungaged sites are considered preliminary.
NASA Astrophysics Data System (ADS)
O'Shea, Bethany; Jankowski, Jerzy
2006-12-01
The major ion composition of Great Artesian Basin groundwater in the lower Namoi River valley is relatively homogeneous in chemical composition. Traditional graphical techniques have been combined with multivariate statistical methods to determine whether subtle differences in the chemical composition of these waters can be delineated. Hierarchical cluster analysis and principal components analysis were successful in delineating minor variations within the groundwaters of the study area that were not visually identified in the graphical techniques applied. Hydrochemical interpretation allowed geochemical processes to be identified in each statistically defined water type and illustrated how these groundwaters differ from one another. Three main geochemical processes were identified in the groundwaters: ion exchange, precipitation, and mixing between waters from different sources. Both statistical methods delineated an anomalous sample suspected of being influenced by magmatic CO2 input. The use of statistical methods to complement traditional graphical techniques for waters appearing homogeneous is emphasized for all investigations of this type. Copyright
ERIC Educational Resources Information Center
Henry, Gary T.; And Others
1992-01-01
A statistical technique is presented for developing performance standards based on benchmark groups. The benchmark groups are selected using a multivariate technique that relies on a squared Euclidean distance method. For each observation unit (a school district in the example), a unique comparison group is selected. (SLD)
Spurdle, Amanda B
2010-06-01
Multifactorial models developed for BRCA1/2 variant classification have proved very useful for delineating BRCA1/2 variants associated with very high risk of cancer, or with little clinical significance. Recent linkage of this quantitative assessment of risk to clinical management guidelines has provided a basis to standardize variant reporting, variant classification and management of families with such variants, and can theoretically be applied to any disease gene. As proof of principle, the multifactorial approach already shows great promise for application to the evaluation of mismatch repair gene variants identified in families with suspected Lynch syndrome. However there is need to be cautious of the noted limitations and caveats of the current model, some of which may be exacerbated by differences in ascertainment and biological pathways to disease for different cancer syndromes.
Kamala, KA; Sankethguddad, S; Sujith, SG; Tantradi, Praveena
2016-01-01
Burning mouth syndrome (BMS) is multifactorial in origin which is typically characterized by burning and painful sensation in an oral cavity demonstrating clinically normal mucosa. Although the cause of BMS is not known, a complex association of biological and psychological factors has been identified, suggesting the existence of a multifactorial etiology. As the symptom of oral burning is seen in various pathological conditions, it is essential for a clinician to be aware of how to differentiate between symptom of oral burning and BMS. An interdisciplinary and systematic approach is required for better patient management. The purpose of this study was to provide the practitioner with an understanding of the local, systemic, and psychosocial factors which may be responsible for oral burning associated with BMS, and review of treatment modalities, therefore providing a foundation for diagnosis and treatment of BMS. PMID:26962284
Reda, Gianluigi; Fattizzo, Bruno; Cassin, Ramona; Flospergher, Elena; Orofino, Nicola; Gianelli, Umberto; Barcellini, Wilma; Cortelezzi, Agostino
2017-03-01
Neutropenia in the setting of acute hematological malignancies may impact disease prognosis, thus affecting therapy dose intensity. This is often due to chemotherapy-induced aplasia as well as to the disease itself. However, chronic neutropenia deserves further investigation, as the management of reversible concomitant causes may avoid treatment delay. The present study describes a case of an acute promyelocytic leukemia patient with chronic severe neutropenia of multifactorial origin, including acute leukemia itself, chemotherapy, autoimmune activation with anti-platelets and anti-neutrophil antibodies positivity, and the rare association of large granular lymphocyte (LGL) expansion. As neutropenia may challenge the diagnosis and treatment of acute malignancies, clinicians and hematopathologists must discuss the differential diagnosis in order to avoid misdiagnosing and undertreating concomitant diseases. In particular, LGL chronic expansion and autoimmunity should be considered.
The epigenetic landscape of alcoholism.
Krishnan, Harish R; Sakharkar, Amul J; Teppen, Tara L; Berkel, Tiffani D M; Pandey, Subhash C
2014-01-01
Alcoholism is a complex psychiatric disorder that has a multifactorial etiology. Epigenetic mechanisms are uniquely capable of accounting for the multifactorial nature of the disease in that they are highly stable and are affected by environmental factors, including alcohol itself. Chromatin remodeling causes changes in gene expression in specific brain regions contributing to the endophenotypes of alcoholism such as tolerance and dependence. The epigenetic mechanisms that regulate changes in gene expression observed in addictive behaviors respond not only to alcohol exposure but also to comorbid psychopathology such as the presence of anxiety and stress. This review summarizes recent developments in epigenetic research that may play a role in alcoholism. We propose that pharmacologically manipulating epigenetic targets, as demonstrated in various preclinical models, hold great therapeutic potential in the treatment and prevention of alcoholism. © 2014 Elsevier Inc. All rights reserved.
2000-06-01
A multifactorial model was used to identify child, sociodemographic, paternal, and maternal characteristics associated with 2 aspects of fathers' parenting. Fathers were interviewed about their caregiving responsibilities at 6, 15, 24, and 36 months, and a subset was videotaped during father-child play at 6 and 36 months. Caregiving activities and sensitivity during play interactions were predicted by different factors. Fathers were more involved in caregiving when fathers worked fewer hours and mothers worked more hours, when fathers and mothers were younger, when fathers had more positive personalities, when mothers reported greater marital intimacy, and when children were boys. Fathers who had less traditional child-rearing beliefs, were older, and reported more marital intimacy were more sensitive during play. These findings are consistent with a multifactorial and multidimensional view of fathering.
Multifactorial Analysis of a Biomarker Pool for Alzheimer Disease Risk in a North Indian Population.
Talwar, Puneet; Grover, Sandeep; Sinha, Juhi; Chandna, Puneet; Agarwal, Rachna; Kushwaha, Suman; Kukreti, Ritushree
2017-01-01
Alzheimer disease (AD) is a progressive neurodegenerative disease with a complex multifactorial etiology. Here, we aim to identify a biomarker pool comprised of genetic variants and blood biomarkers as predictor of AD risk. We performed a case-control study involving 108 cases and 159 non-demented healthy controls to examine the association of multiple biomarkers with AD risk. The APOE genotyping revealed that ε4 allele frequency was significantly high (p value = 0.0001, OR = 2.66, 95% CI 1.58-4.46) in AD as compared to controls, whereas ε2 (p = 0.0430, OR = 0.29, CI 0.07-1.10) was overrepresented in controls. In biochemical assays, significant differences in levels of total copper, free copper, zinc, copper/zinc ratio, iron, epidermal growth factor receptor (EGFR), leptin, and albumin were also observed. The AD risk score (ADRS) as a linear combination of 6 candidate markers involving age, education status, APOE ε4 allele, levels of iron, Cu/Zn ratio, and EGFR was created using stepwise linear discriminant analysis. The area under the ROC curve of the ADRS panel for predicting AD risk was significantly high (AUC = 0.84, p < 0.0001, 95% CI 0.78-0.89, sensitivity = 70.0%, specificity = 83.8%) compared to individual parameters. These findings support the multifactorial etiology of AD and demonstrate the ability of a panel involving 6 biomarkers to discriminate AD cases from non-demented healthy controls. © 2017 S. Karger AG, Basel.
Kuznetsov, L; Simmons, R K; Sandbaek, A; Maindal, H T
2015-04-01
To describe perceptions of chronic care among diabetes patients 6 years after diagnosis by screening and to examine the impact of intensive treatment on patients' perceptions of chronic care. The ADDITION-Denmark (2001-2006) trial compared the effects of intensive multifactorial therapy (IT) with routine care (RC) among individuals with screen-detected diabetes. Perceptions of chronic care were assessed using the Patient Assessment of Chronic Illness Care (PACIC) measure after 6-year follow-up (n = 937). Analysis was by intention-to-treat, accounting for clustering by general practice. The mean (SD) summary PACIC score was 2.4 (0.79) in the RC and 2.4 (0.82) in the IT group. The highest mean (SD) PACIC subscale score was for Delivery System Design/Decision Support [RC: 3.2 (0.95), IT: 3.3 (0.91)] and the lowest was for Follow-up/Coordination [RC: 2.1 (0.84), IT: 2.1 (0.87)]. Perceptions of chronic care did not differ between trial groups. Compared to RC, an intensive multifactorial intervention was not associated with differences in perceptions of chronic care among patients with screen-detected diabetes after 6 years. Intensive treatment does not adversely affect perceptions of chronic care early in the course of the disease. However, there is potentially room for improvement in some aspects of chronic care. © 2014 The Authors. International Journal of Clinical Practice Published by John Wiley & Sons Ltd.
The spectrosome of occupational health problems
de Gaudemaris, Régis; Bicout, Dominique J.
2018-01-01
Given the increased prevalence of cancer, respiratory diseases, and reproductive disorders, for which multifactorial origins are strongly suspected, the impact of the environment on the population represents a substantial public health challenge. Surveillance systems have become an essential public health decision-making tool. Networks have been constructed to facilitate the development of analyses of the multifactorial aspects of the relationships between occupational contexts and health. The aim of this study is to develop and present an approach for the optimal exploitation of observational databases to describe and improve the understanding of the (occupational) environment–health relationships, taking into account key multifactorial aspects. We have developed a spectral analysis (SA) approach that takes into account both the multi-exposure and dynamic natures of occupational health problems (OHPs) and related associations. The main results of this paper are to present the construction method of the “spectrum” and “spectrosome” of OHPs (range and structured list of occupational exposures) and describe the information contained therein with an illustrative example. The approach is illustrated using the case of non-Hodgkin lymphoma (NHL) from the French National Occupational Diseases Surveillance and Prevention Network database as a working example of an occupational disease. We found that the NHL spectrum includes 40 sets of occupational exposures characterized by important multi-exposures, especially solvent combinations or pesticide combinations, but also specific exposures such as polycyclic aromatic hydrocarbons, formaldehyde and ionizing radiation. These findings may be useful for surveillance and the assessment of occupational exposure related to health risks. PMID:29304043
Current and emerging concepts in muscle tension dysphonia: a 30-month review.
Altman, Kenneth W; Atkinson, Cory; Lazarus, Cathy
2005-06-01
The modern theory of hoarseness is that there are multifactorial etiologies contributing to the voice problem. The hypothesis of this study is that muscle tension dysphonia is multifactorial with various contributing etiologies. This project is a retrospective chart review of all patients seen in the Voice Speech and Language Service and Swallowing Center at our institution with a diagnosis of muscle tension (functional hypertensive) dysphonia over a 30-month period. A literature search and review is also performed regarding current and emerging concepts of muscle tension dysphonia. One hundred fifty subjects were identified (60% female, 40% male, with a mean age of 42.3 years). Significant factors in patient history believed to contribute to abnormal voice production were gastroesophageal reflux in 49%, high stress levels in 18%, excessive amounts of voice use in 63%, and excessive loudness demands on voice use in 23%. Otolaryngologic evaluation was performed in 82% of patients, in whom lesions, significant vocal fold edema, or paralysis/paresis was identified in 52.3%. Speech pathology assessment revealed poor breath support, inappropriately low pitch, and visible cervical neck tension in the majority of patients. Inappropriate intensity was observed in 23.3% of patients. This set of multiple contributing factors is discussed in the context of current and emerging understanding of muscle tension dysphonia. Results confirm multifactorial etiologies contributing to hoarseness in the patients identified with muscle tension dysphonia. An interdisciplinary approach to treating all contributing factors portends the best prognosis.
Gilligan, S B; Borecki, I B; Mathew, S; Vijaykumar, M; Malhotra, K C; Rao, D C
1987-09-01
Accessory triradii and the atd angle were examined via complex segregation analysis in order to evaluate possible genetic effects on these dermatoglyphic traits, measured in an endogamous Brahmin caste of peninsular India. The phenotypes considered included: presence of accessory palmar triradii a' and d', associated with the interdigital areas II and IV, respectively; presence of an accessory axial triradius tt' associated with the proximal margin of the palm; and an arctanh-transformation of the atd angle measurement. For all accessory triradii considered in the present investigation familial resemblance was evident. The most parsimonious model which could account for the observed resemblance was a multifactorial model that includes polygenic effects as well as transmissible environmental effects that are inherited in the same pattern as polygenes. Evidence of familial resemblance was also found for the arctanh-transformed atd angle, which could be attributed, initially, to both a major effect and a multifactorial component. Tests of transmission of a putative major gene were performed which yielded results consistent with Mendelian transmission, although an alternative test of no transmission of the major effect also fit the data. In light of these contrasting results we are precluded from accepting with confidence the notion of a major gene influence on the atd angle. We have concluded that the accessory triradii a', d', and tt', and the atd angle are influenced by multifactorial effects, including additive polygenes and possible environmental factors, such as intrauterine effects.
Influence of the thickness of the transverse carpal ligament in carpal tunnel syndrome.
Bartolomé-Villar, A; Pastor-Valero, T; Fuentes-Sanz, A; Varillas-Delgado, D; García-de Lucas, F
To determine if the thickness of the transverse carpal ligament measured by T2 axial magnetic resonance imaging actually influences the onset of carpal tunnel syndrome. 94 patients between January 2015 and June 2016, of whom 28 had carpal tunnel syndrome, underwent magnetic resonance imaging, 37 with discomfort in different carpus regions without symptoms of carpal tunnel and 29 healthy subjects. Two observers performed 3 measurements in 3 different levels, and in the 3 groups of patients. No statistically significant differences in transverse carpal ligament thickness measurements between the carpal tunnel syndrome group and the group without carpal tunnel involvement became apparent, but statistical differences between the control group and the carpal tunnel syndrome group, and between the control group and the group without involvement of the carpal tunnel were observed. In both these groups, the thickness of the transverse ligament was higher than in the control group. An increase in the thickness of the transverse ligament in was found in this study in subjects with involvement of carpal tunnel syndrome as evidenced by numerous studies in the literature. There is no certain causative factor, but rather a set of facts that make onset of the syndrome possible in a specific group of patients. Carpal tunnel syndrome is multifactorial. The thickness of the transverse ligament does not directly affect the onset of symptoms. Copyright © 2017 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.
Microbiomes associated with bovine periodontitis and oral health.
Borsanelli, Ana C; Lappin, David F; Viora, Lorenzo; Bennett, David; Dutra, Iveraldo S; Brandt, Bernd W; Riggio, Marcello P
2018-05-01
Periodontitis is an infectious polymicrobial, immuno-inflammatory disease of multifactorial aetiology that has an impact on the health, production and welfare of ruminants. The objective of the present study was to determine the microbial profiles present in the gingival sulcus of cattle considered periodontally healthy and in the periodontal pocket of animals with periodontitis lesions using high-throughput bacterial 16S rRNA gene sequencing. Subgingival biofilm samples were collected from 40 cattle with periodontitis and 38 periodontally healthy animals. In total, 1923 OTUs were identified and classified into 395 genera or higher taxa. Microbial profiles in health differed significantly from periodontitis in their composition (p < 0.0001, F = 5.30; PERMANOVA) but no statistically significant differences were observed in the diversity of healthy and periodontitis microbiomes. The most prevalent taxa in health were Pseudomonas, Burkholderia and Actinobacteria, whereas in disease these were Prevotella, Fusobacterium and Porphyromonas. The most discriminative taxa in health were Gastranaerophilales, Planifilum and Burkholderia, and in disease these were Elusimicrobia, Synergistes and Propionivibrio. In conclusion, statistically significant difference exists between the microbiome in bovine oral health and periodontitis, with populations showing 72.6% dissimilarity. The diversity of the bacteria found in health and periodontitis were similar and bacteria recognised as periodontal pathogens showed increased abundance in disease. In this context, the main components of bacterial homeostasis in the biofilm of healthy sites and of dysbiosis in periodontal lesions provide unprecedented indicators for the evolution of knowledge about bovine periodontitis. Copyright © 2018 Elsevier B.V. All rights reserved.
Burning mouth syndrome and associated factors: A case-control retrospective study.
Chimenos-Küstner, Eduardo; de Luca-Monasterios, Fiorella; Schemel-Suárez, Mayra; Rodríguez de Rivera-Campillo, María E; Pérez-Pérez, Alejandro M; López-López, José
2017-02-23
Burning mouth syndrome (BMS) can be defined as burning pain or dysesthesia on the tongue and/or other sites of the oral mucosa without a causative identifiable lesion. The discomfort is usually of daily recurrence, with a higher incidence among people aged 50 to 60 years, affecting mostly the female sex and diminishing their quality of life. The aim of this study was to evaluate the association between several pathogenic factors and burning mouth syndrome. 736 medical records of patients diagnosed of burning mouth syndrome and 132 medical records for the control group were studied retrospectively. The study time span was from January 1990 to December 2014. The protocol included: sex, age, type of oral discomfort and location, among other factors. Analysis of the association between pathogenic factors and BMS diagnosis revealed that only 3 factors showed a statistically significant association: triggers (P=.003), parafunctional habits (P=.006), and oral hygiene (P=.012). There were neither statistically significant differences in BMS incidence between sex groups (P=.408) nor association of BMS with the pathogenic factors of substance abuse (P=.915), systemic pathology (P=.685), and dietary habits (P=.904). Parafunctional habits like bruxism and abnormal movements of tongue and lips can explain the BMS main symptomatology. Psychological aspects and systemic factors should be always considered. As a multifactorial disorder, the treatment of BMS should be executed in a holistic way. Copyright © 2016 Elsevier España, S.L.U. All rights reserved.
Acute Injuries in Student Circus Artists with Regard to Gender Specific Differences
Wanke, Eileen M.; McCormack, Moira; Koch, Franziska; Wanke, Alice; Groneberg, David A.
2012-01-01
Purpose Student circus artists train as both artists and athletes with their bodies holding the key to professional success. The daily training load of student circus artists is often associated with maximum physical and psychological stress with injuries posing a threat to a potential professional career. The purpose of this study is the differentiated analysis and evaluation of work accidents in order to initiate the development of injury preventive programs. Methods The 17 years of data were obtained from standardized anonymous work accident records of the Berlin State Accident Insurance (UKB) as well as a State Artist Educational School (n = 169, Male: 70; Female: 99) from student artists. Evaluation and descriptive statistics were conducted with Excel 2007 and PASW Statistics 18. Results The injury risk seems to be relatively low (0.3 injuries/1000h). There are gender specific differences as to the location of injuries. Only 7% of the accidents demand a break of more than 3 days. Injury patterns vary depending on the activity and the employment of props/equipment. 75.2% of work accidents have multifactorial and 24.8% exogenous causes. Conclusions Because physical fitness is all important in the circus arts there are numerous options for injury prevention programs that should be realized subject to gender-specific differences. Follow-ups on chronic complaints and a more individual approach are indispensable due to the very specific activities in the circus arts. PMID:23012634
[Analysis of the Structure of Acute Psychotic Disorder].
Gerardo, Téllez R; Ricardo, Sánchez P; Luis, Eduardo Jaramillo
2012-03-01
Schizophrenia is a clinically heterogeneous disorder. A multifactorial structure of this syndrome has been described in previous reports. The aim of this study was to evaluate what are the possible diagnostic categories in patients having acute psychotic symptoms, studying their clinical characteristics in a cross-sectional study. An instrument for measuring psychotic symptoms was created using previous scales (SANS, SAPS, BPRS, EMUN, Zung depression scale). Using as criteria statistical indexes and redundance of items, the initial instrument having 101 items has been reduced to 57 items. 232 patients with acute psychotic symptoms, in most cases schizophrenia, attending Clínica Nuestra Señora de la Paz in Bogotá and Hospital San Juan de Dios in Chía have been evaluated from April, 2008 to December, 2009. Multivariate statistical methods have been used for analyzing data. A six-factor structure has been found (Deficit, paranoid-aggressive, disorganized, depressive, bizarre delusions, hallucinations). Cluster analysis showed eight subtypes that can be described as: 1) bizarre delusions-hallucinations; 2) deterioration and disorganized behavior; 3) deterioration; 4) deterioration and paranoid-aggressive behavior; 5) bizarre delusions; 6) paranoia-anxiety- aggressiveness; 7) depressive symptoms and bizarre delusions; 8) paranoia and aggressiveness with depressive symptoms These subtypes allow a more exhaustive characterization that those included in standard classification schemes and should be validated in longitudinal studies. Copyright © 2012 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.
Khandelwal, Deepika A; Donga, Shilpa B; Dei, Laxmipriya
2015-01-01
India is one of the countries with high prevalence of anemia during pregnancy. Anemia in pregnancy is multifactorial. Iron deficiency anemia is the most common conditions in a pregnant woman. As per ayurvedic classics, this condition occurs due to improper Rasa Dhatu in mother and continuously increasing fetal demands and is considered as Rasa Pradoshajavikara . A large number of Lauha preparations have been used widely for centuries to cure Anemia. To evaluate efficacy of Punarnava Mandura and Dhatri Lauha on Garbhini Pandu . A total 24 pregnant women with symptoms of Garbhini Pandu were randomly divided into two groups (A and B). In Group A ( n = 15) Punarnava Mandura , two tablets (each of 500 mg) thrice a day with one cup (100 ml) of buttermilk and in Group B ( n = 9) Dhatri Lauha , two tablets (each of 500 mg) thrice a day with luke warm water were administered for 90 days. The assessment was done with subjective parameters such as pallor, general weakness, dyspnea, etc., and objective parameters such as hematological parameters. Results were statistically analyzed using Student's t -test. The results revealed that overall clinical improvement was better in Group A when compared to Group B. Hemoglobin was increased in patients of Group A, which was statistically significant. No adverse drug reaction was observed during the treatment period. Punarnava Mandura is more effective on Garbhini Pandu in comparison to Dhatri Lauha .
Experimental Mathematics and Computational Statistics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bailey, David H.; Borwein, Jonathan M.
2009-04-30
The field of statistics has long been noted for techniques to detect patterns and regularities in numerical data. In this article we explore connections between statistics and the emerging field of 'experimental mathematics'. These includes both applications of experimental mathematics in statistics, as well as statistical methods applied to computational mathematics.
Engaging with the Art & Science of Statistics
ERIC Educational Resources Information Center
Peters, Susan A.
2010-01-01
How can statistics clearly be mathematical and yet distinct from mathematics? The answer lies in the reality that statistics is both an art and a science, and both aspects are important for teaching and learning statistics. Statistics is a mathematical science in that it applies mathematical theories and techniques. Mathematics provides the…
Llombart Blanco, Rafael; Valentí, Andrés; Díaz de Rada, Pablo; Mora, Gonzalo; Valentí, Juan R
2014-11-01
Patellar tendon rupture after total knee replacement is a rare and highly limiting injury with multifactorial aetiology. Many reconstruction techniques have been described with not very predictable results. The use of allografts has been accepted as a suitable solution. A series of seven patients with patellar tendon rupture treated with fresh-frozen tendon allograft reconstruction after knee arthroplasty is presented. Median follow-up is 25 months (20-31). Functional assessment improved, and the knee society score and knee functional score improved from 26 and 16 to 82 and 55, respectively. Median extension lag was 5° (0°-20°), with a median range of motion of 95° (70-100). Radiological study showed a rise of the patella of 22.26 mm. The use of fresh-frozen allografts as a solution to patellar tendon ruptures after knee arthroplasty seems to provide acceptable results. Increased patellar height does not seem to affect functionality. Case series, Level IV.
Morales, Juan F; Montoto, Sebastian Scioli; Fagiolino, Pietro; Ruiz, Maria E
2017-01-01
The Blood-Brain Barrier (BBB) is a physical and biochemical barrier that restricts the entry of certain drugs to the Central Nervous System (CNS), while allowing the passage of others. The ability to predict the permeability of a given molecule through the BBB is a key aspect in CNS drug discovery and development, since neurotherapeutic agents with molecular targets in the CNS should be able to cross the BBB, whereas peripherally acting agents should not, to minimize the risk of CNS adverse effects. In this review we examine and discuss QSAR approaches and current availability of experimental data for the construction of BBB permeability predictive models, focusing on the modeling of the biorelevant parameter unbound partitioning coefficient (Kp,uu). Emphasis is made on two possible strategies to overcome the current limitations of in silico models: considering the prediction of brain penetration as a multifactorial problem, and increasing experimental datasets through accurate and standardized experimental techniques.
A Multidisciplinary Approach for Teaching Statistics and Probability
ERIC Educational Resources Information Center
Rao, C. Radhakrishna
1971-01-01
The author presents a syllabus for an introductory (first year after high school) course in statistics and probability and some methods of teaching statistical techniques. The description comes basically from the procedures used at the Indian Statistical Institute, Calcutta. (JG)
Boe, Debra Thingstad; Parsons, Helen
2009-01-01
Local public health agencies are challenged to continually improve service delivery, yet they frequently operate with constrained resources. Quality improvement methods and techniques such as statistical process control are commonly used in other industries, and they have recently been proposed as a means of improving service delivery and performance in public health settings. We analyzed a quality improvement project undertaken at a local Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) clinic to reduce waiting times and improve client satisfaction with a walk-in nutrition education service. We used statistical process control techniques to evaluate initial process performance, implement an intervention, and assess process improvements. We found that implementation of these techniques significantly reduced waiting time and improved clients' satisfaction with the WIC service. PMID:19608964
Statistical Techniques to Analyze Pesticide Data Program Food Residue Observations.
Szarka, Arpad Z; Hayworth, Carol G; Ramanarayanan, Tharacad S; Joseph, Robert S I
2018-06-26
The U.S. EPA conducts dietary-risk assessments to ensure that levels of pesticides on food in the U.S. food supply are safe. Often these assessments utilize conservative residue estimates, maximum residue levels (MRLs), and a high-end estimate derived from registrant-generated field-trial data sets. A more realistic estimate of consumers' pesticide exposure from food may be obtained by utilizing residues from food-monitoring programs, such as the Pesticide Data Program (PDP) of the U.S. Department of Agriculture. A substantial portion of food-residue concentrations in PDP monitoring programs are below the limits of detection (left-censored), which makes the comparison of regulatory-field-trial and PDP residue levels difficult. In this paper, we present a novel adaption of established statistical techniques, the Kaplan-Meier estimator (K-M), the robust regression on ordered statistic (ROS), and the maximum-likelihood estimator (MLE), to quantify the pesticide-residue concentrations in the presence of heavily censored data sets. The examined statistical approaches include the most commonly used parametric and nonparametric methods for handling left-censored data that have been used in the fields of medical and environmental sciences. This work presents a case study in which data of thiamethoxam residue on bell pepper generated from registrant field trials were compared with PDP-monitoring residue values. The results from the statistical techniques were evaluated and compared with commonly used simple substitution methods for the determination of summary statistics. It was found that the maximum-likelihood estimator (MLE) is the most appropriate statistical method to analyze this residue data set. Using the MLE technique, the data analyses showed that the median and mean PDP bell pepper residue levels were approximately 19 and 7 times lower, respectively, than the corresponding statistics of the field-trial residues.
Preventing falls among older people with mental health problems: a systematic review
2014-01-01
Background Falls are a leading cause of mortality and morbidity in older people and the risk of falling is exacerbated by mental health conditions. Existing reviews have focused on people with dementia and cognitive impairment, but not those with other mental health conditions or in mental health settings. The objective of this review is to evaluate the effectiveness of fall prevention interventions for older people with mental health problems being cared for across all settings. Methods A systematic review of fall prevention interventions for older people with mental health conditions. We undertook electronic database and lateral searches to identify studies reporting data on falls or fall related injuries. Searches were initially conducted in February 2011 and updated in November 2012 and October 2013; no date restrictions were applied. Studies were assessed for risk of bias. Due to heterogeneity results were not pooled but are reported narratively. Results Seventeen RCTs and four uncontrolled studies met the inclusion criteria; 11 involved single interventions and ten multifactorial. Evidence relating to fall reduction was inconsistent. Eight of 14 studies found a reduction in fallers (statistically significant in five), and nine of 14 reported a significant reduction in rate or number of falls. Four studies found a non-significant increase in falls. Multifactorial, multi-disciplinary interventions and those involving exercise, medication review and increasing staff awareness appear to reduce the risk of falls but evidence is mixed and study quality varied. Changes to the environment such as increased supervision or sensory stimulation to reduce agitation may be promising for people with dementia but further evaluation is needed. Most of the studies were undertaken in nursing and residential homes, and none in mental health hospital settings. Conclusions There is a dearth of falls research in mental health settings or which focus on patients with mental health problems despite the high number of falls experienced by this population group. This review highlights the lack of robust evidence to support practitioners to implement practices that prevent people with mental health problems from falling. PMID:24552165
Yong, Paul J
2017-10-01
Endometriosis is a common chronic disease affecting 1 in 10 women of reproductive age, with half of women with endometriosis experiencing deep dyspareunia. A review of research studies on endometriosis indicates a need for a validated question or questionnaire for deep dyspareunia. Moreover, placebo-controlled randomized trials have yet to demonstrate a clear benefit for traditional treatments of endometriosis for the outcome of deep dyspareunia. The reason some patients might not respond to traditional treatments is the multifactorial nature of deep dyspareunia in endometriosis, which can include comorbid conditions (eg, interstitial cystitis and bladder pain syndrome) and central sensitization underlying genito-pelvic pain penetration disorder. In general, there is a lack of a framework that integrates these multifactorial causes to provide a standardized approach to deep dyspareunia in endometriosis. To propose a clinical framework for deep dyspareunia based on a synthesis of pain mechanisms with genito-pelvic pain penetration disorder according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. Narrative review after literature search with the terms (endometriosis AND dyspareunia) OR (dyspareunia AND deep) and after analysis of placebo-controlled randomized trials. Deep dyspareunia presence or absence or deep dyspareunia severity on a numeric rating scale or visual analog scale. Four types of deep dyspareunia are proposed in women with endometriosis: type I that is directly due to endometriosis; type II that is related to a comorbid condition; type III in which genito-pelvic pain penetration disorder is primary; and type IV that is secondary to a combination of types I to III. Four types of deep dyspareunia in endometriosis are proposed, which can be used as a framework in research studies and in clinical practice. Research trials could phenotype or stratify patients by each type. The framework also could give rise to more personalized care for patients by targeting appropriate treatments to each deep dyspareunia type. Yong PJ. Deep Dyspareunia in Endometriosis: A Proposed Framework Based on Pain Mechanisms and Genito-Pelvic Pain Penetration Disorder. Sex Med Rev 2017;5:495-507. Copyright © 2017 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.
Curve fitting and modeling with splines using statistical variable selection techniques
NASA Technical Reports Server (NTRS)
Smith, P. L.
1982-01-01
The successful application of statistical variable selection techniques to fit splines is demonstrated. Major emphasis is given to knot selection, but order determination is also discussed. Two FORTRAN backward elimination programs, using the B-spline basis, were developed. The program for knot elimination is compared in detail with two other spline-fitting methods and several statistical software packages. An example is also given for the two-variable case using a tensor product basis, with a theoretical discussion of the difficulties of their use.
Fitting multidimensional splines using statistical variable selection techniques
NASA Technical Reports Server (NTRS)
Smith, P. L.
1982-01-01
This report demonstrates the successful application of statistical variable selection techniques to fit splines. Major emphasis is given to knot selection, but order determination is also discussed. Two FORTRAN backward elimination programs using the B-spline basis were developed, and the one for knot elimination is compared in detail with two other spline-fitting methods and several statistical software packages. An example is also given for the two-variable case using a tensor product basis, with a theoretical discussion of the difficulties of their use.
Statistical Tests of Reliability of NDE
NASA Technical Reports Server (NTRS)
Baaklini, George Y.; Klima, Stanley J.; Roth, Don J.; Kiser, James D.
1987-01-01
Capabilities of advanced material-testing techniques analyzed. Collection of four reports illustrates statistical method for characterizing flaw-detecting capabilities of sophisticated nondestructive evaluation (NDE). Method used to determine reliability of several state-of-the-art NDE techniques for detecting failure-causing flaws in advanced ceramic materials considered for use in automobiles, airplanes, and space vehicles.
Statistical Techniques for Efficient Indexing and Retrieval of Document Images
ERIC Educational Resources Information Center
Bhardwaj, Anurag
2010-01-01
We have developed statistical techniques to improve the performance of document image search systems where the intermediate step of OCR based transcription is not used. Previous research in this area has largely focused on challenges pertaining to generation of small lexicons for processing handwritten documents and enhancement of poor quality…
Mali, Matilda; Dell'Anna, Maria Michela; Mastrorilli, Piero; Damiani, Leonardo; Ungaro, Nicola; Belviso, Claudia; Fiore, Saverio
2015-11-01
Sediment contamination by metals poses significant risks to coastal ecosystems and is considered to be problematic for dredging operations. The determination of the background values of metal and metalloid distribution based on site-specific variability is fundamental in assessing pollution levels in harbour sediments. The novelty of the present work consists of addressing the scope and limitation of analysing port sediments through the use of conventional statistical techniques (such as: linear regression analysis, construction of cumulative frequency curves and the iterative 2σ technique), that are commonly employed for assessing Regional Geochemical Background (RGB) values in coastal sediments. This study ascertained that although the tout court use of such techniques in determining the RGB values in harbour sediments seems appropriate (the chemical-physical parameters of port sediments fit well with statistical equations), it should nevertheless be avoided because it may be misleading and can mask key aspects of the study area that can only be revealed by further investigations, such as mineralogical and multivariate statistical analyses. Copyright © 2015 Elsevier Ltd. All rights reserved.
A comparison of linear and nonlinear statistical techniques in performance attribution.
Chan, N H; Genovese, C R
2001-01-01
Performance attribution is usually conducted under the linear framework of multifactor models. Although commonly used by practitioners in finance, linear multifactor models are known to be less than satisfactory in many situations. After a brief survey of nonlinear methods, nonlinear statistical techniques are applied to performance attribution of a portfolio constructed from a fixed universe of stocks using factors derived from some commonly used cross sectional linear multifactor models. By rebalancing this portfolio monthly, the cumulative returns for procedures based on standard linear multifactor model and three nonlinear techniques-model selection, additive models, and neural networks-are calculated and compared. It is found that the first two nonlinear techniques, especially in combination, outperform the standard linear model. The results in the neural-network case are inconclusive because of the great variety of possible models. Although these methods are more complicated and may require some tuning, toolboxes are developed and suggestions on calibration are proposed. This paper demonstrates the usefulness of modern nonlinear statistical techniques in performance attribution.
NASA Technical Reports Server (NTRS)
Zimmerman, G. A.; Olsen, E. T.
1992-01-01
Noise power estimation in the High-Resolution Microwave Survey (HRMS) sky survey element is considered as an example of a constant false alarm rate (CFAR) signal detection problem. Order-statistic-based noise power estimators for CFAR detection are considered in terms of required estimator accuracy and estimator dynamic range. By limiting the dynamic range of the value to be estimated, the performance of an order-statistic estimator can be achieved by simpler techniques requiring only a single pass of the data. Simple threshold-and-count techniques are examined, and it is shown how several parallel threshold-and-count estimation devices can be used to expand the dynamic range to meet HRMS system requirements with minimal hardware complexity. An input/output (I/O) efficient limited-precision order-statistic estimator with wide but limited dynamic range is also examined.
Genetics Home Reference: esophageal atresia/tracheoesophageal fistula
... are some genetic conditions more common in particular ethnic groups? Genetic Changes Isolated EA/TEF is considered to be a multifactorial condition, which means that multiple gene variations and environmental factors likely contribute to its occurrence. ...
Rasta, Seyed Hossein; Partovi, Mahsa Eisazadeh; Seyedarabi, Hadi; Javadzadeh, Alireza
2015-01-01
To investigate the effect of preprocessing techniques including contrast enhancement and illumination correction on retinal image quality, a comparative study was carried out. We studied and implemented a few illumination correction and contrast enhancement techniques on color retinal images to find out the best technique for optimum image enhancement. To compare and choose the best illumination correction technique we analyzed the corrected red and green components of color retinal images statistically and visually. The two contrast enhancement techniques were analyzed using a vessel segmentation algorithm by calculating the sensitivity and specificity. The statistical evaluation of the illumination correction techniques were carried out by calculating the coefficients of variation. The dividing method using the median filter to estimate background illumination showed the lowest Coefficients of variations in the red component. The quotient and homomorphic filtering methods after the dividing method presented good results based on their low Coefficients of variations. The contrast limited adaptive histogram equalization increased the sensitivity of the vessel segmentation algorithm up to 5% in the same amount of accuracy. The contrast limited adaptive histogram equalization technique has a higher sensitivity than the polynomial transformation operator as a contrast enhancement technique for vessel segmentation. Three techniques including the dividing method using the median filter to estimate background, quotient based and homomorphic filtering were found as the effective illumination correction techniques based on a statistical evaluation. Applying the local contrast enhancement technique, such as CLAHE, for fundus images presented good potentials in enhancing the vasculature segmentation.
Teaching the Meaning of Statistical Techniques with Microcomputer Simulation.
ERIC Educational Resources Information Center
Lee, Motoko Y.; And Others
Students in an introductory statistics course are often preoccupied with learning the computational routines of specific summary statistics and thereby fail to develop an understanding of the meaning of those statistics or their conceptual basis. To help students develop a better understanding of the meaning of three frequently used statistics,…
NASA Astrophysics Data System (ADS)
McCray, Wilmon Wil L., Jr.
The research was prompted by a need to conduct a study that assesses process improvement, quality management and analytical techniques taught to students in U.S. colleges and universities undergraduate and graduate systems engineering and the computing science discipline (e.g., software engineering, computer science, and information technology) degree programs during their academic training that can be applied to quantitatively manage processes for performance. Everyone involved in executing repeatable processes in the software and systems development lifecycle processes needs to become familiar with the concepts of quantitative management, statistical thinking, process improvement methods and how they relate to process-performance. Organizations are starting to embrace the de facto Software Engineering Institute (SEI) Capability Maturity Model Integration (CMMI RTM) Models as process improvement frameworks to improve business processes performance. High maturity process areas in the CMMI model imply the use of analytical, statistical, quantitative management techniques, and process performance modeling to identify and eliminate sources of variation, continually improve process-performance; reduce cost and predict future outcomes. The research study identifies and provides a detail discussion of the gap analysis findings of process improvement and quantitative analysis techniques taught in U.S. universities systems engineering and computing science degree programs, gaps that exist in the literature, and a comparison analysis which identifies the gaps that exist between the SEI's "healthy ingredients " of a process performance model and courses taught in U.S. universities degree program. The research also heightens awareness that academicians have conducted little research on applicable statistics and quantitative techniques that can be used to demonstrate high maturity as implied in the CMMI models. The research also includes a Monte Carlo simulation optimization model and dashboard that demonstrates the use of statistical methods, statistical process control, sensitivity analysis, quantitative and optimization techniques to establish a baseline and predict future customer satisfaction index scores (outcomes). The American Customer Satisfaction Index (ACSI) model and industry benchmarks were used as a framework for the simulation model.
Confidence Intervals from Realizations of Simulated Nuclear Data
DOE Office of Scientific and Technical Information (OSTI.GOV)
Younes, W.; Ratkiewicz, A.; Ressler, J. J.
2017-09-28
Various statistical techniques are discussed that can be used to assign a level of confidence in the prediction of models that depend on input data with known uncertainties and correlations. The particular techniques reviewed in this paper are: 1) random realizations of the input data using Monte-Carlo methods, 2) the construction of confidence intervals to assess the reliability of model predictions, and 3) resampling techniques to impose statistical constraints on the input data based on additional information. These techniques are illustrated with a calculation of the keff value, based on the 235U(n, f) and 239Pu (n, f) cross sections.
Creighton, Doug; Gruca, Mark; Marsh, Douglas; Murphy, Nancy
2014-11-01
Cervical mobilization and manipulation have been shown to improve cervical range of motion and pain. Rotatory thrust manipulation applied to the lower cervical segments is associated with controversy and the potential for eliciting adverse reactions (AR). The purpose of this clinical trial was to describe two translatory non-thrust mobilization techniques and evaluate their effect on cervical pain, motion restriction, and whether any adverse effects were reported when applied to the C7 segment. This trial included 30 participants with painful and restricted cervical rotation. Participants were randomly assigned to receive one of the two mobilization techniques. Active cervical rotation and pain intensity measurements were recorded pre- and post-intervention. Within group comparisons were determined using the Wilcoxon signed-rank test and between group comparisons were analyzed using the Mann-Whitney U test. Significance was set at P = 0.05. Thirty participants were evaluated immediately after one of the two mobilization techniques was applied. There was a statistically significant difference (improvement) for active cervical rotation after application of the C7 facet distraction technique for both right (P = 0.022) and left (P = 0.022) rotation. Statistically significant improvement was also found for the C7 facet gliding technique for both right (P = 0.022) and left rotation (P = 0.020). Pain reduction was statistically significant for both right and left rotation after application of both techniques. Both mobilization techniques produced similar positive effects and one was not statistically superior to the other. A single application of both C7 mobilization techniques improved active cervical rotation, reduced perceived pain, and did not produce any AR in 30 patients with neck pain and movement limitation. These two non-thrust techniques may offer clinicians an additional safe and effective manual intervention for patients with limited and painful cervical rotation. A more robust experimental design is recommended to further examine these and similar cervical translatory mobilization techniques.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Solaimani, Mohiuddin; Iftekhar, Mohammed; Khan, Latifur
Anomaly detection refers to the identi cation of an irregular or unusual pat- tern which deviates from what is standard, normal, or expected. Such deviated patterns typically correspond to samples of interest and are assigned different labels in different domains, such as outliers, anomalies, exceptions, or malware. Detecting anomalies in fast, voluminous streams of data is a formidable chal- lenge. This paper presents a novel, generic, real-time distributed anomaly detection framework for heterogeneous streaming data where anomalies appear as a group. We have developed a distributed statistical approach to build a model and later use it to detect anomaly. Asmore » a case study, we investigate group anomaly de- tection for a VMware-based cloud data center, which maintains a large number of virtual machines (VMs). We have built our framework using Apache Spark to get higher throughput and lower data processing time on streaming data. We have developed a window-based statistical anomaly detection technique to detect anomalies that appear sporadically. We then relaxed this constraint with higher accuracy by implementing a cluster-based technique to detect sporadic and continuous anomalies. We conclude that our cluster-based technique out- performs other statistical techniques with higher accuracy and lower processing time.« less
Application of multivariable statistical techniques in plant-wide WWTP control strategies analysis.
Flores, X; Comas, J; Roda, I R; Jiménez, L; Gernaey, K V
2007-01-01
The main objective of this paper is to present the application of selected multivariable statistical techniques in plant-wide wastewater treatment plant (WWTP) control strategies analysis. In this study, cluster analysis (CA), principal component analysis/factor analysis (PCA/FA) and discriminant analysis (DA) are applied to the evaluation matrix data set obtained by simulation of several control strategies applied to the plant-wide IWA Benchmark Simulation Model No 2 (BSM2). These techniques allow i) to determine natural groups or clusters of control strategies with a similar behaviour, ii) to find and interpret hidden, complex and casual relation features in the data set and iii) to identify important discriminant variables within the groups found by the cluster analysis. This study illustrates the usefulness of multivariable statistical techniques for both analysis and interpretation of the complex multicriteria data sets and allows an improved use of information for effective evaluation of control strategies.
Data Analysis Techniques for Physical Scientists
NASA Astrophysics Data System (ADS)
Pruneau, Claude A.
2017-10-01
Preface; How to read this book; 1. The scientific method; Part I. Foundation in Probability and Statistics: 2. Probability; 3. Probability models; 4. Classical inference I: estimators; 5. Classical inference II: optimization; 6. Classical inference III: confidence intervals and statistical tests; 7. Bayesian inference; Part II. Measurement Techniques: 8. Basic measurements; 9. Event reconstruction; 10. Correlation functions; 11. The multiple facets of correlation functions; 12. Data correction methods; Part III. Simulation Techniques: 13. Monte Carlo methods; 14. Collision and detector modeling; List of references; Index.
Epigenetics and cardiovascular disease
USDA-ARS?s Scientific Manuscript database
Despite advances in the prevention and management of cardiovascular disease (CVD), this group of multifactorial disorders remains a leading cause of mortality worldwide. CVD is associated with multiple genetic and modifiable risk factors; however, known environmental and genetic influences can only...
Factorials of real negative and imaginary numbers - A new perspective.
Thukral, Ashwani K
2014-01-01
Presently, factorials of real negative numbers and imaginary numbers, except for zero and negative integers are interpolated using the Euler's gamma function. In the present paper, the concept of factorials has been generalised as applicable to real and imaginary numbers, and multifactorials. New functions based on Euler's factorial function have been proposed for the factorials of real negative and imaginary numbers. As per the present concept, the factorials of real negative numbers, are complex numbers. The factorials of real negative integers have their imaginary part equal to zero, thus are real numbers. Similarly, the factorials of imaginary numbers are complex numbers. The moduli of the complex factorials of real negative numbers, and imaginary numbers are equal to their respective real positive number factorials. Fractional factorials and multifactorials have been defined in a new perspective. The proposed concept has also been extended to Euler's gamma function for real negative numbers and imaginary numbers, and beta function.
Kaur, Gaganpreet; Kaur, Maninder; Silakari, Om
2014-01-01
The recent research area endeavors to discover ultimate multi-target ligands, an increasingly feasible and attractive alternative to existing mono-targeted drugs for treatment of complex, multi-factorial inflammation process which underlays plethora of debilitated health conditions. In order to improvise this option, exploration of relevant chemical core scaffold will be an utmost need. Privileged benzimidazole scaffold being historically versatile structural motif could offer a viable starting point in the search for novel multi-target ligands against multi-factorial inflammation process since, when appropriately substituted, it can selectively modulate diverse receptors, pathways and enzymes associated with the pathogenesis of inflammation. Despite this remarkable capability, the multi-target capacity of the benzimidazole scaffold remains largely unexploited. With this in focus, the present review article attempts to provide synopsis of published research to exemplify the valuable use of benzimidazole nucleus and focus on their suitability as starting scaffold to develop multi-targeted anti-inflammatory ligands.
Psczolla, M
2013-10-01
In Germany there is a clear deficit in the non-operative treatment of chronic and complex diseases and pain disorders in acute care hospitals. Only about 20 % of the treatments are carried out in orthopedic hospitals. Hospitals specialized in manual medicine have therefore formed a working group on non-operative orthopedic manual medicine acute care clinics (ANOA). The ANOA has developed a multimodal assessment procedure called the OPS 8-977 which describes the structure and process quality of multimodal and interdisciplinary diagnosis and treatment of the musculoskeletal system. Patients are treated according to clinical pathways oriented on the clinical findings. The increased duration of treatment in the German diagnosis-related groups (DRG) system is compensated for with a supplemental remuneration. Thus, complex and multifactorial orthopedic diseases and pain disorders are conservatively and appropriately treated as inpatient departments of acute care hospitals.
Failure Analysis by Statistical Techniques (FAST). Volume 1. User’s Manual
1974-10-31
REPORT NUMBER DNA 3336F-1 2. OOVT ACCESSION NO 4. TITLE Cand Sublllle) • FAILURE ANALYSIS BY STATISTICAL TECHNIQUES (FAST) Volume I, User’s...SS2), and t’ a facility ( SS7 ). The other three diagrams break down the three critical subsystems. T le median probability of survival of the
USDA-ARS?s Scientific Manuscript database
The mixed linear model (MLM) is currently among the most advanced and flexible statistical modeling techniques and its use in tackling problems in plant pathology has begun surfacing in the literature. The longitudinal MLM is a multivariate extension that handles repeatedly measured data, such as r...
ERIC Educational Resources Information Center
Martin, James L.
This paper reports on attempts by the author to construct a theoretical framework of adult education participation using a theory development process and the corresponding multivariate statistical techniques. Two problems are identified: the lack of theoretical framework in studying problems, and the limiting of statistical analysis to univariate…
ERIC Educational Resources Information Center
Vivo, Juana-Maria; Franco, Manuel
2008-01-01
This article attempts to present a novel application of a method of measuring accuracy for academic success predictors that could be used as a standard. This procedure is known as the receiver operating characteristic (ROC) curve, which comes from statistical decision techniques. The statistical prediction techniques provide predictor models and…
Statistical Techniques Used in Published Articles: A Historical Review of Reviews
ERIC Educational Resources Information Center
Skidmore, Susan Troncoso; Thompson, Bruce
2010-01-01
The purpose of the present study is to provide a historical account and metasynthesis of which statistical techniques are most frequently used in the fields of education and psychology. Six articles reviewing the "American Educational Research Journal" from 1969 to 1997 and five articles reviewing the psychological literature from 1948 to 2001…
A Technique for Merging Areas in Timber Mart-South Data
Jeffrey P. Prestemon; John M. Pye
2000-01-01
For over 20 yr, TimberMart-South (TMS) has been distributing prices of various wood products from southern forests. In the beginning of 1988, the reporting frequency changed from monthly to quarterly, a change readily addressed through a variety established statistical techniques. A more significant statistical challenge is Timber Mart-South's change in 1992 from...
NASA Technical Reports Server (NTRS)
Djorgovski, George
1993-01-01
The existing and forthcoming data bases from NASA missions contain an abundance of information whose complexity cannot be efficiently tapped with simple statistical techniques. Powerful multivariate statistical methods already exist which can be used to harness much of the richness of these data. Automatic classification techniques have been developed to solve the problem of identifying known types of objects in multiparameter data sets, in addition to leading to the discovery of new physical phenomena and classes of objects. We propose an exploratory study and integration of promising techniques in the development of a general and modular classification/analysis system for very large data bases, which would enhance and optimize data management and the use of human research resource.
NASA Astrophysics Data System (ADS)
Poulain, Pierre-Marie; Luther, Douglas S.; Patzert, William C.
1992-11-01
Two techniques have been developed for estimating statistics of inertial oscillations from satellite-tracked drifters. These techniques overcome the difficulties inherent in estimating such statistics from data dependent upon space coordinates that are a function of time. Application of these techniques to tropical surface drifter data collected during the NORPAX, EPOCS, and TOGA programs reveals a latitude-dependent, statistically significant "blue shift" of inertial wave frequency. The latitudinal dependence of the blue shift is similar to predictions based on "global" internal wave spectral models, with a superposition of frequency shifting due to modification of the effective local inertial frequency by the presence of strongly sheared zonal mean currents within 12° of the equator.
NASA Technical Reports Server (NTRS)
Djorgovski, Stanislav
1992-01-01
The existing and forthcoming data bases from NASA missions contain an abundance of information whose complexity cannot be efficiently tapped with simple statistical techniques. Powerful multivariate statistical methods already exist which can be used to harness much of the richness of these data. Automatic classification techniques have been developed to solve the problem of identifying known types of objects in multi parameter data sets, in addition to leading to the discovery of new physical phenomena and classes of objects. We propose an exploratory study and integration of promising techniques in the development of a general and modular classification/analysis system for very large data bases, which would enhance and optimize data management and the use of human research resources.
Shaikh, Muhammad Mujtaba; Memon, Abdul Jabbar; Hussain, Manzoor
2016-09-01
In this article, we describe details of the data used in the research paper "Confidence bounds for energy conservation in electric motors: An economical solution using statistical techniques" [1]. The data presented in this paper is intended to show benefits of high efficiency electric motors over the standard efficiency motors of similar rating in the industrial sector of Pakistan. We explain how the data was collected and then processed by means of formulas to show cost effectiveness of energy efficient motors in terms of three important parameters: annual energy saving, cost saving and payback periods. This data can be further used to construct confidence bounds for the parameters using statistical techniques as described in [1].
Empirical performance of interpolation techniques in risk-neutral density (RND) estimation
NASA Astrophysics Data System (ADS)
Bahaludin, H.; Abdullah, M. H.
2017-03-01
The objective of this study is to evaluate the empirical performance of interpolation techniques in risk-neutral density (RND) estimation. Firstly, the empirical performance is evaluated by using statistical analysis based on the implied mean and the implied variance of RND. Secondly, the interpolation performance is measured based on pricing error. We propose using the leave-one-out cross-validation (LOOCV) pricing error for interpolation selection purposes. The statistical analyses indicate that there are statistical differences between the interpolation techniques:second-order polynomial, fourth-order polynomial and smoothing spline. The results of LOOCV pricing error shows that interpolation by using fourth-order polynomial provides the best fitting to option prices in which it has the lowest value error.
Autoregressive statistical pattern recognition algorithms for damage detection in civil structures
NASA Astrophysics Data System (ADS)
Yao, Ruigen; Pakzad, Shamim N.
2012-08-01
Statistical pattern recognition has recently emerged as a promising set of complementary methods to system identification for automatic structural damage assessment. Its essence is to use well-known concepts in statistics for boundary definition of different pattern classes, such as those for damaged and undamaged structures. In this paper, several statistical pattern recognition algorithms using autoregressive models, including statistical control charts and hypothesis testing, are reviewed as potentially competitive damage detection techniques. To enhance the performance of statistical methods, new feature extraction techniques using model spectra and residual autocorrelation, together with resampling-based threshold construction methods, are proposed. Subsequently, simulated acceleration data from a multi degree-of-freedom system is generated to test and compare the efficiency of the existing and proposed algorithms. Data from laboratory experiments conducted on a truss and a large-scale bridge slab model are then used to further validate the damage detection methods and demonstrate the superior performance of proposed algorithms.
Isaranuwatchai, Wanrudee; Perdrizet, Johnna; Markle-Reid, Maureen; Hoch, Jeffrey S
2017-09-01
Falls among older adults can cause serious morbidity and pose economic burdens on society. Older age is a known risk factor for falls and age has been shown to influence the effectiveness of fall prevention programs. To our knowledge, no studies have explicitly investigated whether cost-effectiveness of a multifactorial fall prevention intervention (the intervention) is influenced by age. This economic evaluation explores: 1) the cost-effectiveness of a multifactorial fall prevention intervention compared to usual care for community-dwelling adults ≥ 75 years at risk of falling in Canada; and 2) the influence of age on the cost-effectiveness of the intervention. Net benefit regression was used to examine the cost-effectiveness of the intervention with willingness-to-pay values ranging from $0-$50,000. Effects were measured as change in the number of falls, from baseline to 6-month follow-up. Costs were measured using a societal perspective. The cost-effectiveness analysis was conducted for both the total sample and by age subgroups (75-84 and 85+ years). For the total sample, the intervention was not economically attractive. However, the intervention was cost-effective at higher willingness-to-pay (WTP) (≥ $25,000) for adults 75-84 years and at lower WTP (< $5,000) for adults 85+ years. The cost-effectiveness of the intervention depends on age and decision makers' WTP to prevent falls. Understanding the influence of age on the cost-effectiveness of an intervention may help to target resources to those who benefit most. Retrospectively registered. Clinicaltrials.gov identifier: NCT00463658 (18 April 2007).
Rasta, Seyed Hossein; Partovi, Mahsa Eisazadeh; Seyedarabi, Hadi; Javadzadeh, Alireza
2015-01-01
To investigate the effect of preprocessing techniques including contrast enhancement and illumination correction on retinal image quality, a comparative study was carried out. We studied and implemented a few illumination correction and contrast enhancement techniques on color retinal images to find out the best technique for optimum image enhancement. To compare and choose the best illumination correction technique we analyzed the corrected red and green components of color retinal images statistically and visually. The two contrast enhancement techniques were analyzed using a vessel segmentation algorithm by calculating the sensitivity and specificity. The statistical evaluation of the illumination correction techniques were carried out by calculating the coefficients of variation. The dividing method using the median filter to estimate background illumination showed the lowest Coefficients of variations in the red component. The quotient and homomorphic filtering methods after the dividing method presented good results based on their low Coefficients of variations. The contrast limited adaptive histogram equalization increased the sensitivity of the vessel segmentation algorithm up to 5% in the same amount of accuracy. The contrast limited adaptive histogram equalization technique has a higher sensitivity than the polynomial transformation operator as a contrast enhancement technique for vessel segmentation. Three techniques including the dividing method using the median filter to estimate background, quotient based and homomorphic filtering were found as the effective illumination correction techniques based on a statistical evaluation. Applying the local contrast enhancement technique, such as CLAHE, for fundus images presented good potentials in enhancing the vasculature segmentation. PMID:25709940
Sci-Thur PM - Colourful Interactions: Highlights 08: ARC TBI using Single-Step Optimized VMAT Fields
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hudson, Alana; Gordon, Deborah; Moore, Roseanne
Purpose: This work outlines a new TBI delivery technique to replace a lateral POP full bolus technique. The new technique is done with VMAT arc delivery, without bolus, treating the patient prone and supine. The benefits of the arc technique include: increased patient experience and safety, better dose conformity, better organ at risk sparing, decreased therapist time and reduction of therapist injuries. Methods: In this work we build on a technique developed by Jahnke et al. We use standard arc fields with gantry speeds corrected for varying distance to the patient followed by a single step VMAT optimization on amore » patient CT to increase dose inhomogeneity and to reduce dose to the lungs (vs. blocks). To compare the arc TBI technique to our full bolus technique, we produced plans on patient CTs for both techniques and evaluated several dosimetric parameters using an ANOVA test. Results and Conclusions: The arc technique is able reduce both the hot areas to the body (D2% reduced from 122.2% to 111.8% p<0.01) and the lungs (mean lung dose reduced from 107.5% to 99.1%, p<0.01), both statistically significant, while maintaining coverage (D98% = 97.8% vs. 94.6%, p=0.313, not statistically significant). We developed a more patient and therapist-friendly TBI treatment technique that utilizes single-step optimized VMAT plans. It was found that this technique was dosimetrically equivalent to our previous lateral technique in terms of coverage and statistically superior in terms of reduced lung dose.« less
Issues in Personality Conceptualizations of Addictive Behaviors.
ERIC Educational Resources Information Center
Sutker, Patricia B.; Allain, Albert N., Jr.
1988-01-01
Describes issues and implications associated with personality conceptualizations of addictive behaviors. Directs attention toward characterizing the sociopolitical climate's effect on identification, evaluation, and management of substance abuse disorders. Explores alcohol and drug use in conceptual schemata encompassing multifactorial,…
Epigenetics lights up the obesity field
USDA-ARS?s Scientific Manuscript database
Despite advances in the prevention and management of cardiovascular disease (CVD), this group of multifactorial disorders remains a leading cause of mortality worldwide. CVD is associated with multiple genetic and modifiable risk factors; however, known environmental and genetic influences can only ...
Grossman, David C; Curry, Susan J; Owens, Douglas K; Barry, Michael J; Caughey, Aaron B; Davidson, Karina W; Doubeni, Chyke A; Epling, John W; Kemper, Alex R; Krist, Alex H; Kubik, Martha; Landefeld, Seth; Mangione, Carol M; Pignone, Michael; Silverstein, Michael; Simon, Melissa A; Tseng, Chien-Wen
2018-04-24
Falls are the leading cause of injury-related morbidity and mortality among older adults in the United States. In 2014, 28.7% of community-dwelling adults 65 years or older reported falling, resulting in 29 million falls (37.5% of which needed medical treatment or restricted activity for a day or longer) and an estimated 33 000 deaths in 2015. To update the 2012 US Preventive Services Task Force (USPSTF) recommendation on the prevention of falls in community-dwelling older adults. The USPSTF reviewed the evidence on the effectiveness and harms of primary care-relevant interventions to prevent falls and fall-related morbidity and mortality in community-dwelling older adults 65 years or older who are not known to have osteoporosis or vitamin D deficiency. The USPSTF found adequate evidence that exercise interventions have a moderate benefit in preventing falls in older adults at increased risk for falls and that multifactorial interventions have a small benefit. The USPSTF found adequate evidence that vitamin D supplementation has no benefit in preventing falls in older adults. The USPSTF found adequate evidence to bound the harms of exercise and multifactorial interventions as no greater than small. The USPSTF found adequate evidence that the overall harms of vitamin D supplementation are small to moderate. The USPSTF recommends exercise interventions to prevent falls in community-dwelling adults 65 years or older who are at increased risk for falls. (B recommendation) The USPSTF recommends that clinicians selectively offer multifactorial interventions to prevent falls in community-dwelling adults 65 years or older who are at increased risk for falls. Existing evidence indicates that the overall net benefit of routinely offering multifactorial interventions to prevent falls is small. When determining whether this service is appropriate for an individual, patients and clinicians should consider the balance of benefits and harms based on the circumstances of prior falls, presence of comorbid medical conditions, and the patient's values and preferences. (C recommendation) The USPSTF recommends against vitamin D supplementation to prevent falls in community-dwelling adults 65 years or older. (D recommendation) These recommendations apply to community-dwelling adults who are not known to have osteoporosis or vitamin D deficiency.
Comparison between two surgical techniques for root coverage with an acellular dermal matrix graft.
Andrade, Patrícia F; Felipe, Maria Emília M C; Novaes, Arthur B; Souza, Sérgio L S; Taba, Mário; Palioto, Daniela B; Grisi, Márcio F M
2008-03-01
The aim of this randomized, controlled, clinical study was to compare two surgical techniques with the acellular dermal matrix graft (ADMG) to evaluate which technique could provide better root coverage. Fifteen patients with bilateral Miller Class I gingival recession areas were selected. In each patient, one recession area was randomly assigned to the control group, while the contra-lateral recession area was assigned to the test group. The ADMG was used in both groups. The control group was treated with a broader flap and vertical-releasing incisions, and the test group was treated with the proposed surgical technique, without releasing incisions. The clinical parameters evaluated before the surgeries and after 12 months were: gingival recession height, probing depth, relative clinical attachment level and the width and thickness of keratinized tissue. There were no statistically significant differences between the groups for all parameters at baseline. After 12 months, there was a statistically significant reduction in recession height in both groups, and there was no statistically significant difference between the techniques with regard to root coverage. Both surgical techniques provided significant reduction in gingival recession height after 12 months, and similar results in relation to root coverage.
Mann, Michael P.; Rizzardo, Jule; Satkowski, Richard
2004-01-01
Accurate streamflow statistics are essential to water resource agencies involved in both science and decision-making. When long-term streamflow data are lacking at a site, estimation techniques are often employed to generate streamflow statistics. However, procedures for accurately estimating streamflow statistics often are lacking. When estimation procedures are developed, they often are not evaluated properly before being applied. Use of unevaluated or underevaluated flow-statistic estimation techniques can result in improper water-resources decision-making. The California State Water Resources Control Board (SWRCB) uses two key techniques, a modified rational equation and drainage basin area-ratio transfer, to estimate streamflow statistics at ungaged locations. These techniques have been implemented to varying degrees, but have not been formally evaluated. For estimating peak flows at the 2-, 5-, 10-, 25-, 50-, and 100-year recurrence intervals, the SWRCB uses the U.S. Geological Surveys (USGS) regional peak-flow equations. In this study, done cooperatively by the USGS and SWRCB, the SWRCB estimated several flow statistics at 40 USGS streamflow gaging stations in the north coast region of California. The SWRCB estimates were made without reference to USGS flow data. The USGS used the streamflow data provided by the 40 stations to generate flow statistics that could be compared with SWRCB estimates for accuracy. While some SWRCB estimates compared favorably with USGS statistics, results were subject to varying degrees of error over the region. Flow-based estimation techniques generally performed better than rain-based methods, especially for estimation of December 15 to March 31 mean daily flows. The USGS peak-flow equations also performed well, but tended to underestimate peak flows. The USGS equations performed within reported error bounds, but will require updating in the future as peak-flow data sets grow larger. Little correlation was discovered between estimation errors and geographic locations or various basin characteristics. However, for 25-percentile year mean-daily-flow estimates for December 15 to March 31, the greatest estimation errors were at east San Francisco Bay area stations with mean annual precipitation less than or equal to 30 inches, and estimated 2-year/24-hour rainfall intensity less than 3 inches.
ERIC Educational Resources Information Center
Brossart, Daniel F.; Parker, Richard I.; Olson, Elizabeth A.; Mahadevan, Lakshmi
2006-01-01
This study explored some practical issues for single-case researchers who rely on visual analysis of graphed data, but who also may consider supplemental use of promising statistical analysis techniques. The study sought to answer three major questions: (a) What is a typical range of effect sizes from these analytic techniques for data from…
Thirumalai Thangarajan, Saravanan; Mani, Umamaheswari; Kumar V, Anand
2017-01-01
Resorption of mandibular ridges is a multifactorial and biomechanical disease that is chronic, progressive, irreversible, and cumulative leading to loss of sulcular depth, vertical dimension loss, and decreased lower facial height. Some common neurological, hormonal, and metabolic disorders affect the adaptability of dentures, and this can be diagnosed by a trained prosthodontist with proper history-taking and clinical examination.The denture becomes passive due to complex neuromuscular control and causes difficulties in impression-making, mastication, and swallowing, which in turn leads to loss of retention and stability in complete dentures. Hence, residual ridge resorption becomes a challenging scenario for a clinician during fabrication of complete dentures. The neutral zone concept plays a significant role in overcoming these challenges. The neutral zone is the area where the outward forces from the tongue are neutralized or nullified by the forces of the lips and cheeks acting inward during functional movements.The neutral zone technique is an alternative approach for the construction of lower complete dentures. It is most effective for dentures where there is a highly atrophic ridge and history of denture instability. The technique aims to construct a denture that is shaped by muscle function and is in harmony with the surrounding oral structures. The technique is by no means new, but it is a valuable one. It is rarely used because of the extra clinical step involved and its complexity. Complete and partial denture failures are often related to non-compliance with neutral zone factors. Thus, the evaluation of the neutral zone is an important factor. Increased retention and stability with reduced chairside time are the salient features of this new approach to any clinically challenging situation in complete dentures.This clinical report describes a modification of the conventional neutral zone technique using improvised procedures to minimize chairside visits for a patient with an atrophic mandibular ridge and neuromuscular incoordination. PMID:28553567
Saravanakumar, Prathibha; Thirumalai Thangarajan, Saravanan; Mani, Umamaheswari; Kumar V, Anand
2017-04-24
Resorption of mandibular ridges is a multifactorial and biomechanical disease that is chronic, progressive, irreversible, and cumulative leading to loss of sulcular depth, vertical dimension loss, and decreased lower facial height. Some common neurological, hormonal, and metabolic disorders affect the adaptability of dentures, and this can be diagnosed by a trained prosthodontist with proper history-taking and clinical examination.The denture becomes passive due to complex neuromuscular control and causes difficulties in impression-making, mastication, and swallowing, which in turn leads to loss of retention and stability in complete dentures. Hence, residual ridge resorption becomes a challenging scenario for a clinician during fabrication of complete dentures. The neutral zone concept plays a significant role in overcoming these challenges. The neutral zone is the area where the outward forces from the tongue are neutralized or nullified by the forces of the lips and cheeks acting inward during functional movements.The neutral zone technique is an alternative approach for the construction of lower complete dentures. It is most effective for dentures where there is a highly atrophic ridge and history of denture instability. The technique aims to construct a denture that is shaped by muscle function and is in harmony with the surrounding oral structures. The technique is by no means new, but it is a valuable one. It is rarely used because of the extra clinical step involved and its complexity. Complete and partial denture failures are often related to non-compliance with neutral zone factors. Thus, the evaluation of the neutral zone is an important factor. Increased retention and stability with reduced chairside time are the salient features of this new approach to any clinically challenging situation in complete dentures.This clinical report describes a modification of the conventional neutral zone technique using improvised procedures to minimize chairside visits for a patient with an atrophic mandibular ridge and neuromuscular incoordination.
Arroyo-Hernández, M; Mellado-Romero, M A; Páramo-Díaz, P; Martín-López, C M; Cano-Egea, J M; Vilá Y Rico, J
2015-01-01
The purpose of this study is to analyze if there is any difference between the arthroscopic reparation of full-thickness supraspinatus tears with simple row technique versus suture bridge technique. We accomplished a retrospective study of 123 patients with full-thickness supraspinatus tears between January 2009 and January 2013 in our hospital. There were 60 simple row reparations, and 63 suture bridge ones. The mean age in the simple row group was 62.9, and in the suture bridge group was 63.3 years old. There were more women than men in both groups (67%). All patients were studied using the Constant test. The mean Constant test in the suture bridge group was 76.7, and in the simple row group was 72.4. We have also accomplished a statistical analysis of each Constant item. Strength was higher in the suture bridge group, with a significant statistical difference (p 0.04). The range of movement was also greater in the suture bridge group, but was not statistically significant. Suture bridge technique has better clinical results than single row reparations, but the difference is not statistically significant (p = 0.298).
Analysis of Variance in Statistical Image Processing
NASA Astrophysics Data System (ADS)
Kurz, Ludwik; Hafed Benteftifa, M.
1997-04-01
A key problem in practical image processing is the detection of specific features in a noisy image. Analysis of variance (ANOVA) techniques can be very effective in such situations, and this book gives a detailed account of the use of ANOVA in statistical image processing. The book begins by describing the statistical representation of images in the various ANOVA models. The authors present a number of computationally efficient algorithms and techniques to deal with such problems as line, edge, and object detection, as well as image restoration and enhancement. By describing the basic principles of these techniques, and showing their use in specific situations, the book will facilitate the design of new algorithms for particular applications. It will be of great interest to graduate students and engineers in the field of image processing and pattern recognition.
NASA Technical Reports Server (NTRS)
Aires, Filipe; Rossow, William B.; Chedin, Alain; Hansen, James E. (Technical Monitor)
2001-01-01
The Independent Component Analysis is a recently developed technique for component extraction. This new method requires the statistical independence of the extracted components, a stronger constraint that uses higher-order statistics, instead of the classical decorrelation, a weaker constraint that uses only second-order statistics. This technique has been used recently for the analysis of geophysical time series with the goal of investigating the causes of variability in observed data (i.e. exploratory approach). We demonstrate with a data simulation experiment that, if initialized with a Principal Component Analysis, the Independent Component Analysis performs a rotation of the classical PCA (or EOF) solution. This rotation uses no localization criterion like other Rotation Techniques (RT), only the global generalization of decorrelation by statistical independence is used. This rotation of the PCA solution seems to be able to solve the tendency of PCA to mix several physical phenomena, even when the signal is just their linear sum.
Statistical assessment of the learning curves of health technologies.
Ramsay, C R; Grant, A M; Wallace, S A; Garthwaite, P H; Monk, A F; Russell, I T
2001-01-01
(1) To describe systematically studies that directly assessed the learning curve effect of health technologies. (2) Systematically to identify 'novel' statistical techniques applied to learning curve data in other fields, such as psychology and manufacturing. (3) To test these statistical techniques in data sets from studies of varying designs to assess health technologies in which learning curve effects are known to exist. METHODS - STUDY SELECTION (HEALTH TECHNOLOGY ASSESSMENT LITERATURE REVIEW): For a study to be included, it had to include a formal analysis of the learning curve of a health technology using a graphical, tabular or statistical technique. METHODS - STUDY SELECTION (NON-HEALTH TECHNOLOGY ASSESSMENT LITERATURE SEARCH): For a study to be included, it had to include a formal assessment of a learning curve using a statistical technique that had not been identified in the previous search. METHODS - DATA SOURCES: Six clinical and 16 non-clinical biomedical databases were searched. A limited amount of handsearching and scanning of reference lists was also undertaken. METHODS - DATA EXTRACTION (HEALTH TECHNOLOGY ASSESSMENT LITERATURE REVIEW): A number of study characteristics were abstracted from the papers such as study design, study size, number of operators and the statistical method used. METHODS - DATA EXTRACTION (NON-HEALTH TECHNOLOGY ASSESSMENT LITERATURE SEARCH): The new statistical techniques identified were categorised into four subgroups of increasing complexity: exploratory data analysis; simple series data analysis; complex data structure analysis, generic techniques. METHODS - TESTING OF STATISTICAL METHODS: Some of the statistical methods identified in the systematic searches for single (simple) operator series data and for multiple (complex) operator series data were illustrated and explored using three data sets. The first was a case series of 190 consecutive laparoscopic fundoplication procedures performed by a single surgeon; the second was a case series of consecutive laparoscopic cholecystectomy procedures performed by ten surgeons; the third was randomised trial data derived from the laparoscopic procedure arm of a multicentre trial of groin hernia repair, supplemented by data from non-randomised operations performed during the trial. RESULTS - HEALTH TECHNOLOGY ASSESSMENT LITERATURE REVIEW: Of 4571 abstracts identified, 272 (6%) were later included in the study after review of the full paper. Some 51% of studies assessed a surgical minimal access technique and 95% were case series. The statistical method used most often (60%) was splitting the data into consecutive parts (such as halves or thirds), with only 14% attempting a more formal statistical analysis. The reporting of the studies was poor, with 31% giving no details of data collection methods. RESULTS - NON-HEALTH TECHNOLOGY ASSESSMENT LITERATURE SEARCH: Of 9431 abstracts assessed, 115 (1%) were deemed appropriate for further investigation and, of these, 18 were included in the study. All of the methods for complex data sets were identified in the non-clinical literature. These were discriminant analysis, two-stage estimation of learning rates, generalised estimating equations, multilevel models, latent curve models, time series models and stochastic parameter models. In addition, eight new shapes of learning curves were identified. RESULTS - TESTING OF STATISTICAL METHODS: No one particular shape of learning curve performed significantly better than another. The performance of 'operation time' as a proxy for learning differed between the three procedures. Multilevel modelling using the laparoscopic cholecystectomy data demonstrated and measured surgeon-specific and confounding effects. The inclusion of non-randomised cases, despite the possible limitations of the method, enhanced the interpretation of learning effects. CONCLUSIONS - HEALTH TECHNOLOGY ASSESSMENT LITERATURE REVIEW: The statistical methods used for assessing learning effects in health technology assessment have been crude and the reporting of studies poor. CONCLUSIONS - NON-HEALTH TECHNOLOGY ASSESSMENT LITERATURE SEARCH: A number of statistical methods for assessing learning effects were identified that had not hitherto been used in health technology assessment. There was a hierarchy of methods for the identification and measurement of learning, and the more sophisticated methods for both have had little if any use in health technology assessment. This demonstrated the value of considering fields outside clinical research when addressing methodological issues in health technology assessment. CONCLUSIONS - TESTING OF STATISTICAL METHODS: It has been demonstrated that the portfolio of techniques identified can enhance investigations of learning curve effects. (ABSTRACT TRUNCATED)
The Effect of Student-Driven Projects on the Development of Statistical Reasoning
ERIC Educational Resources Information Center
Sovak, Melissa M.
2010-01-01
Research has shown that even if students pass a standard introductory statistics course, they often still lack the ability to reason statistically. Many instructional techniques for enhancing the development of statistical reasoning have been discussed, although there is often little to no experimental evidence that they produce effective results…
ERIC Educational Resources Information Center
DeMark, Sarah F.; Behrens, John T.
2004-01-01
Whereas great advances have been made in the statistical sophistication of assessments in terms of evidence accumulation and task selection, relatively little statistical work has explored the possibility of applying statistical techniques to data for the purposes of determining appropriate domain understanding and to generate task-level scoring…
An Applied Statistics Course for Systematics and Ecology PhD Students
ERIC Educational Resources Information Center
Ojeda, Mario Miguel; Sosa, Victoria
2002-01-01
Statistics education is under review at all educational levels. Statistical concepts, as well as the use of statistical methods and techniques, can be taught in at least two contrasting ways. Specifically, (1) teaching can be theoretically and mathematically oriented, or (2) it can be less mathematically oriented being focused, instead, on…
The dosimetry of brachytherapy-induced erectile dysfunction
DOE Office of Scientific and Technical Information (OSTI.GOV)
Merrick, Gregory S.; Butler, Wayne M
2003-12-31
There is emerging evidence that brachytherapy-induced erectile dysfunction (ED) is technique-related and may be minimized by careful attention to source placement. Herein, we review the relationship between radiation doses to the prostate gland/surrounding structures and the development of brachytherapy-induced ED. The permanent prostate brachytherapy literature was reviewed using MEDLINE searches to ensure completeness. Although the site-specific structure associated with brachytherapy-induced ED remains unknown, there is an increasing body of data implicating the proximal penis. With day 0 CT-based dosimetry, the dose to 50% (D{sub 50}) and 25% (D{sub 25}) of the bulb of the penis should be maintained below 40%more » and 60% mPD, respectively, while the crura D{sub 50} should be maintained below 28% mPD to maximize post-brachytherapy potency. To date, there is no data to suggest that either radiation doses to the neurovascular bundles or choice of isotope is associated with brachytherapy-induced ED, while conflicting data has been reported regarding radiation dose to the prostate and the use of supplemental external beam radiation therapy. Although the etiology of brachytherapy-induced ED is likely multifactorial, the available data supports the proximal penis as an important site-specific structure. Refinements in implant technique, including preplanning and intraoperative seed placement, will result in lower radiation doses to the proximal penis with potential improvement in potency preservation.« less
Rausch, Tobias; Thomas, Alun; Camp, Nicola J.; Cannon-Albright, Lisa A.; Facelli, Julio C.
2008-01-01
This paper describes a novel algorithm to analyze genetic linkage data using pattern recognition techniques and genetic algorithms (GA). The method allows a search for regions of the chromosome that may contain genetic variations that jointly predispose individuals for a particular disease. The method uses correlation analysis, filtering theory and genetic algorithms (GA) to achieve this goal. Because current genome scans use from hundreds to hundreds of thousands of markers, two versions of the method have been implemented. The first is an exhaustive analysis version that can be used to visualize, explore, and analyze small genetic data sets for two marker correlations; the second is a GA version, which uses a parallel implementation allowing searches of higher-order correlations in large data sets. Results on simulated data sets indicate that the method can be informative in the identification of major disease loci and gene-gene interactions in genome-wide linkage data and that further exploration of these techniques is justified. The results presented for both variants of the method show that it can help genetic epidemiologists to identify promising combinations of genetic factors that might predispose to complex disorders. In particular, the correlation analysis of IBD expression patterns might hint to possible gene-gene interactions and the filtering might be a fruitful approach to distinguish true correlation signals from noise. PMID:18547558
What We Know About the Brain Structure-Function Relationship.
Batista-García-Ramó, Karla; Fernández-Verdecia, Caridad Ivette
2018-04-18
How the human brain works is still a question, as is its implication with brain architecture: the non-trivial structure–function relationship. The main hypothesis is that the anatomic architecture conditions, but does not determine, the neural network dynamic. The functional connectivity cannot be explained only considering the anatomical substrate. This involves complex and controversial aspects of the neuroscience field and that the methods and methodologies to obtain structural and functional connectivity are not always rigorously applied. The goal of the present article is to discuss about the progress made to elucidate the structure–function relationship of the Central Nervous System, particularly at the brain level, based on results from human and animal studies. The current novel systems and neuroimaging techniques with high resolutive physio-structural capacity have brought about the development of an integral framework of different structural and morphometric tools such as image processing, computational modeling and graph theory. Different laboratories have contributed with in vivo, in vitro and computational/mathematical models to study the intrinsic neural activity patterns based on anatomical connections. We conclude that multi-modal techniques of neuroimaging are required such as an improvement on methodologies for obtaining structural and functional connectivity. Even though simulations of the intrinsic neural activity based on anatomical connectivity can reproduce much of the observed patterns of empirical functional connectivity, future models should be multifactorial to elucidate multi-scale relationships and to infer disorder mechanisms.
Castro-Santos, Patricia; Díaz-Peña, Roberto
2017-09-01
Most rheumatic diseases are complex or multifactorial entities with pathogeneses that interact with both multiple genetic factors and a high number of diverse environmental factors. Knowledge of the human genome sequence and its diversity among populations has provided a crucial step forward in our understanding of genetic diseases, identifying many genetic loci or genes associated with diverse phenotypes. In general, susceptibility to autoimmunity is associated with multiple risk factors, but the mechanism of the environmental component influence is poorly understood. Studies in twins have demonstrated that genetics do not explain the totality of the pathogenesis of rheumatic diseases. One method of modulating gene expression through environmental effects is via epigenetic modifications. These techniques open a new field for identifying useful new biomarkers and therapeutic targets. In this context, the development of "-omics" techniques is an opportunity to progress in our knowledge of complex diseases, impacting the discovery of new potential biomarkers suitable for their introduction into clinical practice. In this review, we focus on the recent advances in the fields of genomics and epigenomics in rheumatic diseases and their potential to be useful for the diagnosis, follow-up, and treatment of these diseases. The ultimate aim of genomic studies in any human disease is to understand its pathogenesis, thereby enabling the prediction of the evolution of the disease to establish new treatments and address the development of personalized therapies.
Tea and cinnamon polyphenols improve the metabolic syndrome
USDA-ARS?s Scientific Manuscript database
The metabolic syndrome is often a precursor of chronic diseases including type 2 diabetes, cardiovascular diseases, and neurodegenerative diseases including Alzheimer’s disease. Since the metabolic syndrome is multi-factorial, strategies for reducing its incidence and consequences must also be mult...
RATIONALE. Childhood asthma is a multifactorial disease whose pathogenesis involves complex interplay between genetic susceptibility and modulating external factors. Therefore, effectively characterizing these multiple etiological pathways, or “endotypes”, requires an integrative...
ERIC Educational Resources Information Center
Crawford, Shawn; And Others
1990-01-01
The utility of developmental behavioral genetics in the study of reading disability is considered. Research which has found reading disability to be partly genetically determined is cited, and future research applications are discussed. (Author/JDD)
A novel approach to simulate gene-environment interactions in complex diseases.
Amato, Roberto; Pinelli, Michele; D'Andrea, Daniel; Miele, Gennaro; Nicodemi, Mario; Raiconi, Giancarlo; Cocozza, Sergio
2010-01-05
Complex diseases are multifactorial traits caused by both genetic and environmental factors. They represent the major part of human diseases and include those with largest prevalence and mortality (cancer, heart disease, obesity, etc.). Despite a large amount of information that has been collected about both genetic and environmental risk factors, there are few examples of studies on their interactions in epidemiological literature. One reason can be the incomplete knowledge of the power of statistical methods designed to search for risk factors and their interactions in these data sets. An improvement in this direction would lead to a better understanding and description of gene-environment interactions. To this aim, a possible strategy is to challenge the different statistical methods against data sets where the underlying phenomenon is completely known and fully controllable, for example simulated ones. We present a mathematical approach that models gene-environment interactions. By this method it is possible to generate simulated populations having gene-environment interactions of any form, involving any number of genetic and environmental factors and also allowing non-linear interactions as epistasis. In particular, we implemented a simple version of this model in a Gene-Environment iNteraction Simulator (GENS), a tool designed to simulate case-control data sets where a one gene-one environment interaction influences the disease risk. The main aim has been to allow the input of population characteristics by using standard epidemiological measures and to implement constraints to make the simulator behaviour biologically meaningful. By the multi-logistic model implemented in GENS it is possible to simulate case-control samples of complex disease where gene-environment interactions influence the disease risk. The user has full control of the main characteristics of the simulated population and a Monte Carlo process allows random variability. A knowledge-based approach reduces the complexity of the mathematical model by using reasonable biological constraints and makes the simulation more understandable in biological terms. Simulated data sets can be used for the assessment of novel statistical methods or for the evaluation of the statistical power when designing a study.
Vitamin D receptor gene Alw I, Fok I, Apa I, and Taq I polymorphisms in patients with urinary stone.
Seo, Ill Young; Kang, In-Hong; Chae, Soo-Cheon; Park, Seung Chol; Lee, Young-Jin; Yang, Yun Sik; Ryu, Soo Bang; Rim, Joung Sik
2010-04-01
To evaluate vitamin D receptor (VDR) gene polymorphisms in Korean patients so as to identify the candidate genes associated with urinary stones. Urinary stones are a multifactorial disease that includes various genetic factors. A normal control group of 535 healthy subjects and 278 patients with urinary stones was evaluated. Of 125 patients who presented stone samples, 102 had calcium stones on chemical analysis. The VDR gene Alw I, Fok I, Apa I, and Taq I polymorphisms were evaluated using the polymerase chain reaction-restriction fragment length polymorphism analysis. Allelic and genotypic frequencies were calculated to identify associations in both groups. The haplotype frequencies of the VDR gene polymorphisms for multiple loci were also determined. For the VDR gene Alw I, Fok I, Apa I, and Taq I polymorphisms, there was no statistically significant difference between the patients with urinary stones and the healthy controls. There was also no statistically significant difference between the patients with calcium stones and the healthy controls. A novel haplotype (Ht 4; CTTT) was identified in 13.5% of the patients with urinary stones and in 8.3% of the controls (P = .001). The haplotype frequencies were significantly different between the patients with calcium stones and the controls (P = .004). The VDR gene Alw I, Fok I, Apa I, and Taq I polymorphisms does not seem to be candidate genetic markers for urinary stones in Korean patients. However, 1 novel haplotype of the VDR gene polymorphisms for multiple loci might be a candidate genetic marker. Copyright 2010 Elsevier Inc. All rights reserved.
Berggren, M; Stenvall, M; Olofsson, B; Gustafson, Y
2008-06-01
A randomized, controlled fall-prevention study including 199 patients operated on for femoral neck fracture reduced inpatient falls and injuries. No statistically significant effects of the intervention program could be detected after discharge. It seems that fall-prevention must be part of everyday life in fall-prone old people. This study evaluates whether a postoperative multidisciplinary, multifactorial fall-prevention program performed by a geriatric team that reduced inpatient falls and injuries had any continuing effect after discharge. The intervention consisted of staff education, systematic assessment and treatment of fall risk factors and vitamin D and calcium supplementation. The randomized, controlled trial with a one-year follow-up at Umeå University Hospital, Sweden, included 199 patients operated on for femoral neck fracture, aged > or = 70 years. After one year 44 participants had fallen 138 times in the intervention group compared with 55 participants and 191 falls in the control group. The crude postoperative fall incidence was 4.16/1,000 days in the intervention group vs. 6.43/1,000 days in the control group. The incidence rate ratio was 0.64 (95% CI: 0.40-1.02, p = 0.063). Seven new fractures occurred in the intervention group and 11 in the control group. A team applying comprehensive geriatric assessment and rehabilitation, including prevention and treatment of fall-risk factors, reduced inpatient falls and injuries, but no statistically significant effects of the program could be detected after discharge. It seems that fall-prevention must be part of everyday life in fall-prone elderly.
Genetic Factors Affecting Late-Onset Alzheimer's Disease Susceptibility.
Rezazadeh, Maryam; Khorrami, Aziz; Yeghaneh, Tarlan; Talebi, Mahnaz; Kiani, Seyed Jalal; Heshmati, Yaser; Gharesouran, Jalal
2016-03-01
Alzheimer's disease is considered a progressive brain disease in the older population. Late-onset Alzheimer's disease (LOAD) as a multifactorial dementia has a polygenic inheritance. Age, environment, and lifestyle along with a growing number of genetic factors have been reported as risk factors for LOAD. Our aim was to present results of LOAD association studies that have been done in northwestern Iran, and we also explored possible interactions with apolipoprotein E (APOE) status. We re-evaluated the association of these markers in dominant, recessive, and additive models. In all, 160 LOAD and 163 healthy control subjects of Azeri Turkish ethnicity were studied. The Chi-square test with Yates' correction and Fisher's exact test were used for statistical analysis. A Bonferroni-corrected p value, based on the number of statistical tests, was considered significant. Our results confirmed that chemokine receptor type 2 (CCR2), estrogen receptor 1 (ESR1), toll-like receptor 2 (TLR2), tumor necrosis factor alpha (TNF α), APOE, bridging integrator 1 (BIN1), and phosphatidylinositol-binding clathrin assembly protein (PICALM) are LOAD susceptibility loci in Azeri Turk ancestry populations. Among them, variants of CCR2, ESR1, TNF α, and APOE revealed associations in three different genetic models. After adjusting for APOE, the association (both allelic and genotypic) with CCR2, BIN1, and ESRα (PvuII) was evident only among subjects without the APOE ε4, whereas the association with CCR5, without Bonferroni correction, was significant only among subjects carrying the APOE ε4 allele. This result is an evidence of a synergistic and antagonistic effect of APOE on variant associations with LOAD.
Caroff, Jildaz; Mihalea, Cristian; Da Ros, Valerio; Yagi, Takanobu; Iacobucci, Marta; Ikka, Léon; Moret, Jacques; Spelle, Laurent
2017-07-01
Recent reports have revealed a worsening of aneurysm occlusion between WEB treatment baseline and angiographic follow-up due to "compression" of the device. We utilized computational fluid dynamics (CFD) in order to determine whether the underlying mechanism of this worsening is flow related. We included data from all consecutive patients treated in our institution with a WEB for unruptured aneurysms located either at the middle cerebral artery or basilar tip. The CFD study was performed using pre-operative 3D rotational angiography. From digital subtraction follow-up angiographies patients were dichotomized into two groups: one with WEB "compression" and one without. We performed statistical analyses to determine a potential correlation between WEB compression and CFD inflow ratio. Between July 2012 and June 2015, a total of 22 unruptured middle cerebral artery or basilar tip aneurysms were treated with a WEB device in our department. Three patients were excluded from the analysis and the mean follow-up period was 17months. Eleven WEBs presented "compression" during follow-up. Interestingly, device "compression" was statistically correlated to the CFD inflow ratio (P=0.018), although not to aneurysm volume, aspect ratio or neck size. The mechanisms underlying the worsening of aneurysm occlusion in WEB-treated patients due to device compression are most likely complex as well as multifactorial. However, it is apparent from our pilot study that a high arterial inflow is, at least, partially involved. Further theoretical and animal research studies are needed to increase our understanding of this phenomenon. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
Acciuffi, Sara; Meyer, Frank; Bauschke, Astrid; Settmacher, Utz; Lippert, Hans; Croner, Roland; Altendorf-Hofmann, Annelore
2018-03-01
The investigation of the predictors of outcome after hepatic resection for solitary colorectal liver metastasis. We recruited 350 patients with solitary colorectal liver metastasis at the University Hospitals of Jena and Magdeburg, who underwent curative liver resection between 1993 and 2014. All patients had follow-up until death or till summer 2016. The follow-up data concern 96.6% of observed patients. The 5- and 10-year overall survival rates were 47 and 28%, respectively. The 5- and 10-year disease-free survival rates were 30 and 20%, respectively. The analysis of the prognostic factors revealed that the pT category of primary tumour, size and grade of the metastasis and extension of the liver resection had no statistically significant impact on survival and recurrence rates. In multivariate analysis, age, status of lymph node metastasis at the primary tumour, location of primary tumour, time of appearance of the metastasis, the use of preoperative chemotherapy and the presence of extrahepatic tumour proved to be independent statistically significant predictors for the prognosis. Moreover, patients with rectal cancer had a lower intrahepatic recurrence rate, but a higher extrahepatic recurrence rate. The long-term follow-up of patients with R0-resected liver metastasis is multifactorially influenced. Age and comorbidity have a role only in the overall survival. More than three lymph node metastasis reduced both the overall and disease-free survival. Extrahepatic tumour had a negative influence on the extrahepatic recurrence and on the overall survival. Neither overall survival nor recurrence rates was improved using neoadjuvant chemotherapy.
Acetabular cup position and risk of dislocation in primary total hip arthroplasty.
Seagrave, Kurt G; Troelsen, Anders; Malchau, Henrik; Husted, Henrik; Gromov, Kirill
2017-02-01
Background and purpose - Hip dislocation is one of the most common complications following total hip arthroplasty (THA). Several factors that affect dislocation have been identified, including acetabular cup positioning. Optimal values for cup inclination and anteversion are debatable. We performed a systematic review to describe the different methods for measuring cup placement, target zones for cup positioning, and the association between cup positioning and dislocation following primary THA. Methods - A systematic search of literature in the PubMed database was performed (January and February 2016) to identify articles that compared acetabular cup positioning and the risk of dislocation. Surgical approach and methods for measurement of cup angles were also considered. Results - 28 articles were determined to be relevant to our research question. Some articles demonstrated that cup positioning influenced postoperative dislocation whereas others did not. The majority of articles could not identify a statistically significant difference between dislocating and non-dislocating THA with regard to mean angles of cup anteversion and inclination. Most of the articles that assessed cup placement within the Lewinnek safe zone did not show a statistically significant reduction in dislocation rate. Alternative target ranges have been proposed by several authors. Interpretation - The Lewinnek safe zone could not be justified. It is difficult to draw broad conclusions regarding a definitive target zone for cup positioning in THA, due to variability between studies and the likely multifactorial nature of THA dislocation. Future studies comparing cup positioning and dislocation rate should investigate surgical approach separately. Standardized tools for measurement of cup positioning should be implemented to allow comparison between studies.
Acetabular cup position and risk of dislocation in primary total hip arthroplasty
Seagrave, Kurt G; Troelsen, Anders; Malchau, Henrik; Husted, Henrik; Gromov, Kirill
2017-01-01
Background and purpose — Hip dislocation is one of the most common complications following total hip arthroplasty (THA). Several factors that affect dislocation have been identified, including acetabular cup positioning. Optimal values for cup inclination and anteversion are debatable. We performed a systematic review to describe the different methods for measuring cup placement, target zones for cup positioning, and the association between cup positioning and dislocation following primary THA. Methods — A systematic search of literature in the PubMed database was performed (January and February 2016) to identify articles that compared acetabular cup positioning and the risk of dislocation. Surgical approach and methods for measurement of cup angles were also considered. Results— 28 articles were determined to be relevant to our research question. Some articles demonstrated that cup positioning influenced postoperative dislocation whereas others did not. The majority of articles could not identify a statistically significant difference between dislocating and non-dislocating THA with regard to mean angles of cup anteversion and inclination. Most of the articles that assessed cup placement within the Lewinnek safe zone did not show a statistically significant reduction in dislocation rate. Alternative target ranges have been proposed by several authors. Interpretation— The Lewinnek safe zone could not be justified. It is difficult to draw broad conclusions regarding a definitive target zone for cup positioning in THA, due to variability between studies and the likely multifactorial nature of THA dislocation. Future studies comparing cup positioning and dislocation rate should investigate surgical approach separately. Standardized tools for measurement of cup positioning should be implemented to allow comparison between studies. PMID:27879150
Nielsen, Rasmus Østergaard; Malisoux, Laurent; Møller, Merete; Theisen, Daniel; Parner, Erik Thorlund
2016-04-01
The etiological mechanism underpinning any sports-related injury is complex and multifactorial. Frequently, athletes perceive "excessive training" as the principal factor in their injury, an observation that is biologically plausible yet somewhat ambiguous. If the applied training load is suddenly increased, this may increase the risk for sports injury development, irrespective of the absolute amount of training. Indeed, little to no rigorous scientific evidence exists to support the hypothesis that fluctuations in training load, compared to absolute training load, are more important in explaining sports injury development. One reason for this could be that prospective data from scientific studies should be analyzed in a different manner. Time-to-event analysis is a useful statistical tool in which to analyze the influence of changing exposures on injury risk. However, the potential of time-to-event analysis remains insufficiently exploited in sports injury research. Therefore, the purpose of the present article was to present and discuss measures of association used in time-to-event analyses and to present the advanced concept of time-varying exposures and outcomes. In the paper, different measures of association, such as cumulative relative risk, cumulative risk difference, and the classical hazard rate ratio, are presented in a nontechnical manner, and suggestions for interpretation of study results are provided. To summarize, time-to-event analysis complements the statistical arsenal of sports injury prevention researchers, because it enables them to analyze the complex and highly dynamic reality of injury etiology, injury recurrence, and time to recovery across a range of sporting contexts.
Dhatrilauha: Right choice for iron deficiency anemia in pregnancy.
Roy, Anuradha; Dwivedi, Manjari
2014-01-01
Anemia in pregnancy is multi-factorial. Iron deficiency anemia (IDA) is the most common one. Major cause is increased demand of iron during pregnancy. In Ayurveda, under Pandu-Roga the features of anemia are described. It is characterized by Vaivarnyata or Varnanasha (change/destruction in normal color of the body), a disorder of Pitta vitiation. Ayurvedic management is an effective way of curing anemia in general by a large number of Lauha preparations of which Dhatrilauha has been used widely for centuries. To evaluate the effect of Dhatrilauha in the management of IDA based on the scientific parameters among pregnant patients. A total of 58 cases were selected by simple randomized sampling method as per inclusion criteria of pregnant women between 4(th) and 7(th) months of pregnancy with a clinical diagnosis and laboratory confirmation of IDA. Dhatrilauha 500 mg in two divided doses after food with normal potable water were given for 45 days with three follow-ups, each of 15 days intervals. Final assessment was done after completion of 45 days and results were statistically analyzed by using Cochran's Q-test and Student's t-test. Dhatrilauha showed statistically significant (P < 0.01) improvement in the majority of sign-symptoms and objective parameters such as weakness, fatigue, palpitation, effort intolerance, breathlessness, heartburn, pallor, constipation, hemoglobin, red blood cells (RBC), hematocrit, mean corpuscular volume, mean corpuscular hemoglobin concentration, RBC distribution width, mean platelet volume, serum iron, and total iron binding capacity. Dhatrilauha possesses many fold effectiveness in anemia (IDA), which was evidenced with the significant results obtained in the majority of parameters in this study.
An Automated Energy Detection Algorithm Based on Morphological and Statistical Processing Techniques
2018-01-09
ARL-TR-8272 ● JAN 2018 US Army Research Laboratory An Automated Energy Detection Algorithm Based on Morphological and...is no longer needed. Do not return it to the originator. ARL-TR-8272 ● JAN 2018 US Army Research Laboratory An Automated Energy ...4. TITLE AND SUBTITLE An Automated Energy Detection Algorithm Based on Morphological and Statistical Processing Techniques 5a. CONTRACT NUMBER
The purpose of this memorandum is to inform recipients of concerns regarding Army Corps of Engineers statistical techniques, provide a list of installations and FWS where SiteStat/GridStats (SS/GS) have been used, and to provide direction on communicating with the public on the use of these 'tools' by USACE.
Application of multivariate statistical techniques in microbial ecology
Paliy, O.; Shankar, V.
2016-01-01
Recent advances in high-throughput methods of molecular analyses have led to an explosion of studies generating large scale ecological datasets. Especially noticeable effect has been attained in the field of microbial ecology, where new experimental approaches provided in-depth assessments of the composition, functions, and dynamic changes of complex microbial communities. Because even a single high-throughput experiment produces large amounts of data, powerful statistical techniques of multivariate analysis are well suited to analyze and interpret these datasets. Many different multivariate techniques are available, and often it is not clear which method should be applied to a particular dataset. In this review we describe and compare the most widely used multivariate statistical techniques including exploratory, interpretive, and discriminatory procedures. We consider several important limitations and assumptions of these methods, and we present examples of how these approaches have been utilized in recent studies to provide insight into the ecology of the microbial world. Finally, we offer suggestions for the selection of appropriate methods based on the research question and dataset structure. PMID:26786791
The Statistical Package for the Social Sciences (SPSS) as an adjunct to pharmacokinetic analysis.
Mather, L E; Austin, K L
1983-01-01
Computer techniques for numerical analysis are well known to pharmacokineticists. Powerful techniques for data file management have been developed by social scientists but have, in general, been ignored by pharmacokineticists because of their apparent lack of ability to interface with pharmacokinetic programs. Extensive use has been made of the Statistical Package for the Social Sciences (SPSS) for its data handling capabilities, but at the same time, techniques have been developed within SPSS to interface with pharmacokinetic programs of the users' choice and to carry out a variety of user-defined pharmacokinetic tasks within SPSS commands, apart from the expected variety of statistical tasks. Because it is based on a ubiquitous package, this methodology has all of the benefits of excellent documentation, interchangeability between different types and sizes of machines and true portability of techniques and data files. An example is given of the total management of a pharmacokinetic study previously reported in the literature by the authors.
On the Use of Statistics in Design and the Implications for Deterministic Computer Experiments
NASA Technical Reports Server (NTRS)
Simpson, Timothy W.; Peplinski, Jesse; Koch, Patrick N.; Allen, Janet K.
1997-01-01
Perhaps the most prevalent use of statistics in engineering design is through Taguchi's parameter and robust design -- using orthogonal arrays to compute signal-to-noise ratios in a process of design improvement. In our view, however, there is an equally exciting use of statistics in design that could become just as prevalent: it is the concept of metamodeling whereby statistical models are built to approximate detailed computer analysis codes. Although computers continue to get faster, analysis codes always seem to keep pace so that their computational time remains non-trivial. Through metamodeling, approximations of these codes are built that are orders of magnitude cheaper to run. These metamodels can then be linked to optimization routines for fast analysis, or they can serve as a bridge for integrating analysis codes across different domains. In this paper we first review metamodeling techniques that encompass design of experiments, response surface methodology, Taguchi methods, neural networks, inductive learning, and kriging. We discuss their existing applications in engineering design and then address the dangers of applying traditional statistical techniques to approximate deterministic computer analysis codes. We conclude with recommendations for the appropriate use of metamodeling techniques in given situations and how common pitfalls can be avoided.
Statistical and Economic Techniques for Site-specific Nematode Management.
Liu, Zheng; Griffin, Terry; Kirkpatrick, Terrence L
2014-03-01
Recent advances in precision agriculture technologies and spatial statistics allow realistic, site-specific estimation of nematode damage to field crops and provide a platform for the site-specific delivery of nematicides within individual fields. This paper reviews the spatial statistical techniques that model correlations among neighboring observations and develop a spatial economic analysis to determine the potential of site-specific nematicide application. The spatial econometric methodology applied in the context of site-specific crop yield response contributes to closing the gap between data analysis and realistic site-specific nematicide recommendations and helps to provide a practical method of site-specifically controlling nematodes.
Genome-wide association studies in pharmacogenetics research debate
Bailey, Kent R; Cheng, Cheng
2016-01-01
Will genome-wide association studies (GWAS) ‘work’ for pharmacogenetics research? This question was the topic of a staged debate, with pro and con sides, aimed to bring out the strengths and weaknesses of GWAS for pharmacogenetics studies. After a full day of seminars at the Fifth Statistical Analysis Workshop of the Pharmacogenetics Research Network, the lively debate was held – appropriately – at Goonies Comedy Club in Rochester (MN, USA). The pro side emphasized that the many GWAS successes for identifying genetic variants associated with disease risk show that it works; that the current genotyping platforms are efficient, with good imputation methods to fill in missing data; that its global assessment is always a success even if no significant associations are detected; and that genetic effects are likely to be large because humans have not evolved in a drug-therapy environment. By contrast, the con side emphasized that we have limited knowledge of the complexity of the genome; limited clinical phenotypes compromise studies; the likely multifactorial nature of drug response clouding the small genetic effects; and limitations of sample size and replication studies in pharmacogenetic studies. Lively and insightful discussions emphasized further research efforts that might benefit GWAS in pharmacogenetics. PMID:20235786
Stabilization/solidification of hot dip galvanizing ash using different binders.
Vinter, S; Montanes, M T; Bednarik, V; Hrivnova, P
2016-12-15
This study focuses on solidification of hot dip-galvanizing ash with a high content of zinc and soluble substances. The main purpose of this paper is to immobilize these pollutants into a matrix and allow a safer way for landfill disposal of that waste. Three different binders (Portland cement, fly ash and coal fluidized-bed combustion ash) were used for the waste solidification. Effectiveness of the process was evaluated using leaching test according to EN 12457-4 and by using the variance analysis and the categorical multifactorial test. In the leaching test, four parameters were observed: pH, zinc concentration in leachate, and concentration of chlorides and dissolved substances in leachate. The acquired data was then processed using statistical software to find an optimal solidifying ratio of the addition of binder, water, and waste to the mixture, with the aim to fulfil the requirement for landfill disposal set by the Council Decision 2003/33/EC. The influence on the main observed parameters (relative amount of water and a binder) on the effectiveness of the used method and their influence of measured parameters was also studied. Copyright © 2016 Elsevier B.V. All rights reserved.
Genetic susceptibility and periodontal disease: a retrospective study on a large italian sample.
Tettamanti, L; Gaudio, R M; Iapichino, A; Mucchi, D; Tagliabue, A
2017-01-01
Periodontal disease (PD) is a multifactorial illness in which environment and host interact. The genetic component plays a key role in the onset of PD. In fact the genetic compound can modulate the inflammation of the mucous membranes and the loss of alveolar bone. The genetics of PD is not well understood. Previous studies suggest a strong association between PD occurrence and individual genetic profile. The role of genetic susceptibility could impact on the clinical manifestations of PD, and consequently on prevention and therapy. Genetic polymorphisms of VRD, IL6 and IL10 were investigated in Italian adults affected by PD. 571 cases classified according the criteria of the American Academy of Periodontology were included. All patients were Italian coming from three areas according to italian institute of statistics (ISTAT) (www.istat.it/it/archivio/regioni). The sample comprised 379 patients from North (66%), 152 from Central (26%) and 40 of South (8%). No significant differences were found among allele distribution. Chronic PD is a complex disease caused by a combination of genetic susceptibility, patients habits (oral hygiene, smoking, alcohol consumption) and oral pathogens. In our report no differences were detected among three Italian regions in allele distribution.
Use of lipidomics to investigate sebum dysfunction in juvenile acne[S
Sinagra, Jo-Linda; Capitanio, Bruno
2016-01-01
Acne is a multifactorial skin disorder frequently observed during adolescence with different grades of severity. Multiple factors centering on sebum secretion are implicated in acne pathogenesis. Despite the recognized role of sebum, its compositional complexity and limited analytical approaches have hampered investigation of alterations specifically associated with acne. To examine the profiles of lipid distribution in acne sebum, 61 adolescents (29 males and 32 females) were enrolled in this study. Seventeen subjects presented no apparent clinical signs of acne. The 44 affected individuals were clinically classified as mild (13 individuals), moderate (19 individuals), and severe (12 individuals) acne. Sebum was sampled from the forehead with SebutapeTM adhesive patches. Profiles of neutral lipids were acquired with rapid-resolution reversed-phase/HPLC-TOF/MS in positive ion mode. Univariate and multivariate statistical analyses led to the identification of lipid species with significantly different levels between healthy and acne sebum. The majority of differentiating lipid species were diacylglycerols (DGs), followed by fatty acyls, sterols, and prenols. Overall, the data indicated an association between the clinical grading of acne and sebaceous lipid fingerprints and highlighted DGs as more abundant in sebum from adolescents affected with acne. PMID:27127078
The Difference in Interleukin-19 Serum on Degrees of Acne Vulgaris Severity.
Mochtar, Moerbono; Murasmita, Alamanda; Irawanto, M Eko; Julianto, Indah; Kariosentono, Harijono; Waskito, Fajar
2018-01-01
Acne vulgaris is a multifactorial disease. Recent study showed that inflammation does have a central role in the formation of both inflammatory and noninflammatory lesions in acne vulgaris. There are various findings of proinflammatory cytokines related to acne vulgaris, but no previous study correlate interleukin- (IL-) 19 to acne vulgaris. This pilot study aims to look at difference in IL-19 serum concentration on degrees of severity of acne vulgaris. This is an analytical observational cross-sectional study. Sample subjects were patients with acne vulgaris who met the inclusion criteria. Enzyme-linked immunosorbent assay (ELISA) study was applied to measure IL-19 serum. Analysis test found statistically significant difference between IL-19 serum concentration of group of patients with mild acne vulgaris and that of group of patients with severe acne vulgaris. Moreover, analysis revealed significant difference between IL-19 serum concentration of group of patients with moderate acne vulgaris and that of group of patients with severe acne vulgaris. There are differences in serum levels of IL-19 on the severity of acne vulgaris. The significant difference might show that inflammation has a core role in severity of acne vulgaris, and IL-19 might potentially be related to acne vulgaris.
Challenges in Achieving Food Security in India
Upadhyay, R Prakash; Palanivel, C
2011-01-01
First Millennium Development Goal states the target of “Halving hunger by 2015”. Sadly, the recent statistics for India present a very gloomy picture. India currently has the largest number of undernourished people in the world and this is in spite of the fact that it has made substantial progress in health determinants over the past decades and ranks second worldwide in farm output. The causes of existing food insecurity can be better viewed under three concepts namely the: ‘traditional concept’ which includes factors such as unavailability of food and poor purchasing capacity; ‘socio-demographic concept’ which includes illiteracy, unemployment, overcrowding, poor environmental conditions and gender bias; ‘politico-developmental concept’ comprising of factors such as lack of intersectoral coordination and political will, poorly monitored nutritional programmes and inadequate public food distribution system. If the Millennium Development Goal is to be achieved by 2015, efforts to improve food and nutrition security have to increase considerably. Priority has to be assigned to agriculture and rural development along with promoting women empowerment, ensuring sustainable employment and improving environmental conditions (water, sanitation and hygiene). As the problem is multi-factorial, so the solution needs to be multi-sectoral. PMID:23113100
Kostopoulou, Sotiria; Parpa, Efi; Tsilika, Eleni; Katsaragakis, Stylianos; Papazoglou, Irene; Zygogianni, Anna; Galanos, Antonis; Mystakidou, Kyriaki
2018-04-01
The present study assesses the relationship between patient dignity in advanced cancer and the following variables: psychological distress, preparatory grief, and sociodemographic and clinical characteristics. The sample consisted of 120 patients with advanced cancer. The self-administered questionnaires were as follows: the Preparatory Grief in Advanced Cancer Patients (PGAC), the Patient Dignity Inventory-Greek (PDI-Gr), the Greek Schedule for Attitudes toward Hastened Death (G-SAHD), and the Greek version of the Hospital Anxiety and Depression Scale (G-HADS). Moderate to strong statistically significant correlations were found between the 4 subscales of PDI-Gr (psychological distress, body image and role identity, self-esteem, and social support) with G-HADS, G-SAHD, and PGAC ( P < .005), while physical distress and dependency was moderately correlated with depression. Multifactorial analyses showed that preparatory grief, depression, and age influenced psychological distress, while preparatory grief, depression, and performance status influenced body image and role identity. Preparatory grief, psychological distress, and physical symptoms had significant associations with perceptions of dignity among patients with advanced cancer. Clinicians should assess and attend to dignity-distressing factors in the care of patients with advanced cancer.
Association of interleukin 8 -251 A/T gene polymorphism with periodontitis in Indonesia
NASA Astrophysics Data System (ADS)
Jessica, C.; Alwadris, T. T.; Prasetyo, S. R.; Puspitawati, R.; Auerkari, E. I.
2018-05-01
Periodontitis is a chronic multifactorial disease resulting from an interaction between periodontal pathogen bacteria, host, and environmental factors. Genetics has been identified to contribute to the pathogenesis and susceptibility of periodontitis, and interleukin 8 (IL-8) gene is expressing one of the chemokines involved in the inflammation process. This study aimed to evaluate the association of IL-8 -251 A/T gene polymorphism with periodontitis in Indonesian subjects. The study was conducted by genotyping 72 samples of patients with various severity of periodontitis and 41 samples of healthy controls group using PCR-RFLP method. Genotypes of the IL-8 gene polymorphism in periodontitis patients were not significantly different with those in healthy controls. Those with TT genotype were 3.40 times less likely to develop periodontitis compared to AA genotype (95% CI). There was a significant difference in allele frequencies (p < 0.05, OR = 1.828, 95% CI), suggesting that allele T is a risk factor to periodontitis. Statistical analyses with Chi-square testing showed no significant association of IL-8 -251 A/T gene polymorphism and the severity of periodontitis in Indonesia. However, IL-8 -251 A/T gene polymorphism might contribute to the susceptibility of periodontitis.
Diagnosis of IBS: symptoms, symptom-based criteria, biomarkers or 'psychomarkers'?
Sood, Ruchit; Law, Graham R; Ford, Alexander C
2014-11-01
IBS is estimated to have a prevalence of up to 20% in Western populations and results in substantial costs to health-care services worldwide, estimated to be US$1 billion per year in the USA. IBS remains difficult to diagnose due to its multifactorial aetiology, heterogeneous nature and overlap of symptoms with organic pathologies, such as coeliac disease and IBD. As a result, IBS often continues to be a diagnosis of exclusion, resulting in unnecessary investigations. Available methods for the diagnosis of IBS-including the current gold standard, the Rome III criteria-perform only moderately well. Visceral hypersensitivity and altered pain perception do not discriminate between IBS and other functional gastrointestinal diseases or health with any great accuracy. Attention has now turned to developing novel biomarkers and using psychological markers (so-called psychomarkers) to aid the diagnosis of IBS. This Review describes how useful symptoms, symptom-based criteria, biomarkers and psychomarkers, and indeed combinations of all these approaches, are in the diagnosis of IBS. Future directions in diagnosing IBS could include combining demographic data, gastrointestinal symptoms, biomarkers and psychomarkers using statistical methods. Latent class analysis to distinguish between IBS and non-IBS symptom profiles might also represent a promising avenue for future research.
Salleh, Fatmah M; Al-Mekhlafi, Abdulsalam M; Nordin, Anisah; Yasin, 'Azlin M; Al-Mekhlafi, Hesham M; Moktar, Norhayati
2011-01-01
This study was conducted to evaluate the modification of the usual Gram-chromotrope staining technique developed in-house known as Gram-chromotrope Kinyoun (GCK) in comparison with the Weber Modified Trichrome (WMT) staining technique; as the reference technique. Two hundred and ninety fecal specimens received by the Microbiology Diagnostic Laboratory of Hospital Universiti Kebangsaan Malaysia were examined for the presence of microsporidial spores. The sensitivity and specificity of GCK compared to the reference technique were 98% and 98.3%, respectively. The positive and negative predictive values were 92.5% and 99.6%, respectively. The agreement between the reference technique and the GCK staining technique was statistically significant by Kappa statistics (K = 0.941, P < 0.001). It is concluded that the GCK staining technique has high sensitivity and specificity in the detection of microsporidial spores in fecal specimens. Hence, it is recommended to be used in the diagnosis of intestinal microsporidiosis. Copyright © 2011 Elsevier Inc. All rights reserved.
Utility of Dermatoglyphic Pattern in Prediction of Caries in Children of Telangana Region, India.
Asif, Shaik M; Babu, Dara Bg; Naheeda, Shaik
2017-06-01
Dermatoglyphics is an extremely useful tool as a preliminary investigation method for diagnosing suspected genetic disorders. Caries being a multifactorial disease with the influence of genetic pattern, early identification of caries risk children with dermatoglyphics can help in using effective and efficient caries preventive measures. The study was undertaken to record and know the frequency of occurrence of fingerprint patterns among children with caries and in children without caries. A total of 400 schoolchildren in the age group of 5 to 12 years were selected from a private school, Warangal, Telangana, India. Of 400 schoolchildren, 200 children were with caries group and 200 children were in caries-free group. Children with dental caries in five or more teeth based on the decayed, missing, filled teeth index performed were considered as study group, and the control group was normal healthy children without any dental caries. The fingerprints of each child were recorded using stamp pad method, and type of dermatoglyphic pattern of each digit was recorded based on Cummins and Midlo method. Data obtained were put for statistical analysis; p < 0.001 was considered statistically significant. Although the frequency of whorl pattern was more prevalent in caries group, it was statistically significant on the left hand third digit of females and on the right hand third digit and the left hand fourth digit of males. Fingerprints of female caries-free group showed maximum of ulnar loop and males showed maximum of arches. There was a decrease in total ridge count in caries group, especially in males. Dermatoglyphics could be an appropriate method to explore the possibility of a noninvasive and an early predictor for dental caries. Dermatoglyphics has a future role in identifying people with or at increased risk for dental caries so that risk reduction measures or earlier therapy may be instituted.
Metsemakers, W-J; Handojo, K; Reynders, P; Sermon, A; Vanderschot, P; Nijs, S
2015-04-01
Despite modern advances in the treatment of tibial shaft fractures, complications including nonunion, malunion, and infection remain relatively frequent. A better understanding of these injuries and its complications could lead to prevention rather than treatment strategies. A retrospective study was performed to identify risk factors for deep infection and compromised fracture healing after intramedullary nailing (IMN) of tibial shaft fractures. Between January 2000 and January 2012, 480 consecutive patients with 486 tibial shaft fractures were enrolled in the study. Statistical analysis was performed to determine predictors of deep infection and compromised fracture healing. Compromised fracture healing was subdivided in delayed union and nonunion. The following independent variables were selected for analysis: age, sex, smoking, obesity, diabetes, American Society of Anaesthesiologists (ASA) classification, polytrauma, fracture type, open fractures, Gustilo type, primary external fixation (EF), time to nailing (TTN) and reaming. As primary statistical evaluation we performed a univariate analysis, followed by a multiple logistic regression model. Univariate regression analysis revealed similar risk factors for delayed union and nonunion, including fracture type, open fractures and Gustilo type. Factors affecting the occurrence of deep infection in this model were primary EF, a prolonged TTN, open fractures and Gustilo type. Multiple logistic regression analysis revealed polytrauma as the single risk factor for nonunion. With respect to delayed union, no risk factors could be identified. In the same statistical model, deep infection was correlated with primary EF. The purpose of this study was to evaluate risk factors of poor outcome after IMN of tibial shaft fractures. The univariate regression analysis showed that the nature of complications after tibial shaft nailing could be multifactorial. This was not confirmed in a multiple logistic regression model, which only revealed polytrauma and primary EF as risk factors for nonunion and deep infection, respectively. Future strategies should focus on prevention in high-risk populations such as polytrauma patients treated with EF. Copyright © 2014 Elsevier Ltd. All rights reserved.
SICK BUILDING SYNDROME: POSSIBLE ASSOCIATIONS WITH EXPOSURE TO MYCOTOXINS FROM INDOOR AIR FUNGI.
Introduction. Chronic human illness associated with residential or occupational buildings, commonly referred to as sick building syndrome (SBS), may be a multifactorial condition, involving in some cases volatile organic compounds, CO or CO2, pesticides, biologic agents, temperat...
Suicidal Tendencies in the Elderly.
ERIC Educational Resources Information Center
Achte, Kalle
1988-01-01
Claims elderly suicides are more frequent, and more likely to be multifactorial, including loneliness, isolation, depression, somatic illnesses, having suffered numerous losses, and injuries to the self-esteem (concerns regarding emptiness, uselessness, and body image). Aggressive impulses previously neutralized by work and social life now break…
A case of coffee-ground emesis in an elderly patient
De Palma, Giovanni D; Persico, Marcello; Forestieri, Pietro
2014-01-01
Key Clinical Message Black esophagus is an exceeding rare disorder with a multifactorial etiology. Clinical presentation is generally related to upper gastrointestinal bleeding. Diagnosis is based on endoscopic images. Overall mortality is largely related to the underlying medical condition. PMID:25356232
McCormick, Frank; Gupta, Anil; Bruce, Ben; Harris, Josh; Abrams, Geoff; Wilson, Hillary; Hussey, Kristen; Cole, Brian J.
2014-01-01
Purpose: The purpose of this study was to measure and compare the subjective, objective, and radiographic healing outcomes of single-row (SR), double-row (DR), and transosseous equivalent (TOE) suture techniques for arthroscopic rotator cuff repair. Materials and Methods: A retrospective comparative analysis of arthroscopic rotator cuff repairs by one surgeon from 2004 to 2010 at minimum 2-year followup was performed. Cohorts were matched for age, sex, and tear size. Subjective outcome variables included ASES, Constant, SST, UCLA, and SF-12 scores. Objective outcome variables included strength, active range of motion (ROM). Radiographic healing was assessed by magnetic resonance imaging (MRI). Statistical analysis was performed using analysis of variance (ANOVA), Mann — Whitney and Kruskal — Wallis tests with significance, and the Fisher exact probability test <0.05. Results: Sixty-three patients completed the study requirements (20 SR, 21 DR, 22 TOE). There was a clinically and statistically significant improvement in outcomes with all repair techniques (ASES mean improvement P = <0.0001). The mean final ASES scores were: SR 83; (SD 21.4); DR 87 (SD 18.2); TOE 87 (SD 13.2); (P = 0.73). There was a statistically significant improvement in strength for each repair technique (P < 0.001). There was no significant difference between techniques across all secondary outcome assessments: ASES improvement, Constant, SST, UCLA, SF-12, ROM, Strength, and MRI re-tear rates. There was a decrease in re-tear rates from single row (22%) to double-row (18%) to transosseous equivalent (11%); however, this difference was not statistically significant (P = 0.6). Conclusions: Compared to preoperatively, arthroscopic rotator cuff repair, using SR, DR, or TOE techniques, yielded a clinically and statistically significant improvement in subjective and objective outcomes at a minimum 2-year follow-up. Level of Evidence: Therapeutic level 3. PMID:24926159
MANCOVA for one way classification with homogeneity of regression coefficient vectors
NASA Astrophysics Data System (ADS)
Mokesh Rayalu, G.; Ravisankar, J.; Mythili, G. Y.
2017-11-01
The MANOVA and MANCOVA are the extensions of the univariate ANOVA and ANCOVA techniques to multidimensional or vector valued observations. The assumption of a Gaussian distribution has been replaced with the Multivariate Gaussian distribution for the vectors data and residual term variables in the statistical models of these techniques. The objective of MANCOVA is to determine if there are statistically reliable mean differences that can be demonstrated between groups later modifying the newly created variable. When randomization assignment of samples or subjects to groups is not possible, multivariate analysis of covariance (MANCOVA) provides statistical matching of groups by adjusting dependent variables as if all subjects scored the same on the covariates. In this research article, an extension has been made to the MANCOVA technique with more number of covariates and homogeneity of regression coefficient vectors is also tested.
Air Quality Forecasting through Different Statistical and Artificial Intelligence Techniques
NASA Astrophysics Data System (ADS)
Mishra, D.; Goyal, P.
2014-12-01
Urban air pollution forecasting has emerged as an acute problem in recent years because there are sever environmental degradation due to increase in harmful air pollutants in the ambient atmosphere. In this study, there are different types of statistical as well as artificial intelligence techniques are used for forecasting and analysis of air pollution over Delhi urban area. These techniques are principle component analysis (PCA), multiple linear regression (MLR) and artificial neural network (ANN) and the forecasting are observed in good agreement with the observed concentrations through Central Pollution Control Board (CPCB) at different locations in Delhi. But such methods suffers from disadvantages like they provide limited accuracy as they are unable to predict the extreme points i.e. the pollution maximum and minimum cut-offs cannot be determined using such approach. Also, such methods are inefficient approach for better output forecasting. But with the advancement in technology and research, an alternative to the above traditional methods has been proposed i.e. the coupling of statistical techniques with artificial Intelligence (AI) can be used for forecasting purposes. The coupling of PCA, ANN and fuzzy logic is used for forecasting of air pollutant over Delhi urban area. The statistical measures e.g., correlation coefficient (R), normalized mean square error (NMSE), fractional bias (FB) and index of agreement (IOA) of the proposed model are observed in better agreement with the all other models. Hence, the coupling of statistical and artificial intelligence can be use for the forecasting of air pollutant over urban area.
Mavrodi, Alexandra; Ohanyan, Ani; Kechagias, Nikos; Tsekos, Antonis; Vahtsevanos, Konstantinos
2015-09-01
Post-operative complications of various degrees of severity are commonly observed in third molar impaction surgery. For this reason, a surgical procedure that decreases the trauma of bone and soft tissues should be a priority for surgeons. In the present study, we compare the efficacy and the post-operative complications of patients to whom two different surgical techniques were applied for impacted lower third molar extraction. Patients of the first group underwent the classical bur technique, while patients of the second group underwent another technique, in which an elevator was placed on the buccal surface of the impacted molar in order to luxate the alveolar socket more easily. Comparing the two techniques, we observed a statistically significant decrease in the duration of the procedure and in the need for tooth sectioning when applying the second surgical technique, while the post-operative complications were similar in the two groups. We also found a statistically significant lower incidence of lingual nerve lesions and only a slightly higher frequency of sharp mandibular bone irregularities in the second group, which however was not statistically significant. The results of our study indicate that the surgical technique using an elevator on the buccal surface of the tooth seems to be a reliable method to extract impacted third molars safely, easily, quickly and with the minimum trauma to the surrounding tissues.
A Multifactorial, Criteria-based Progressive Algorithm for Hamstring Injury Treatment.
Mendiguchia, Jurdan; Martinez-Ruiz, Enrique; Edouard, Pascal; Morin, Jean-Benoît; Martinez-Martinez, Francisco; Idoate, Fernando; Mendez-Villanueva, Alberto
2017-07-01
Given the prevalence of hamstring injuries in football, a rehabilitation program that effectively promotes muscle tissue repair and functional recovery is paramount to minimize reinjury risk and optimize player performance and availability. This study aimed to assess the concurrent effectiveness of administering an individualized and multifactorial criteria-based algorithm (rehabilitation algorithm [RA]) on hamstring injury rehabilitation in comparison with using a general rehabilitation protocol (RP). Implementing a double-blind randomized controlled trial approach, two equal groups of 24 football players (48 total) completed either an RA group or a validated RP group 5 d after an acute hamstring injury. Within 6 months after return to sport, six hamstring reinjuries occurred in RP versus one injury in RA (relative risk = 6, 90% confidence interval = 1-35; clinical inference: very likely beneficial effect). The average duration of return to sport was possibly quicker (effect size = 0.34 ± 0.42) in RP (23.2 ± 11.7 d) compared with RA (25.5 ± 7.8 d) (-13.8%, 90% confidence interval = -34.0% to 3.4%; clinical inference: possibly small effect). At the time to return to sport, RA players showed substantially better 10-m time, maximal sprinting speed, and greater mechanical variables related to speed (i.e., maximum theoretical speed and maximal horizontal power) than the RP. Although return to sport was slower, male football players who underwent an individualized, multifactorial, criteria-based algorithm with a performance- and primary risk factor-oriented training program from the early stages of the process markedly decreased the risk of reinjury compared with a general protocol where long-length strength training exercises were prioritized.
Alonso-Domínguez, Rosario; Gómez-Marcos, Manuel A; Patino-Alonso, Maria C; Sánchez-Aguadero, Natalia; Agudo-Conde, Cristina; Castaño-Sánchez, Carmen; García-Ortiz, Luis; Recio-Rodríguez, José I
2017-01-01
Introduction New information and communication technologies (ICTs) may promote lifestyle changes, but no adequate evidence is available on their combined effect of ICTs with multifactorial interventions aimed at improving diet and increasing physical activity in patients with type 2 diabetes mellitus (DM2). The primary objective of this study is to assess the effect of a multifactorial intervention to increase physical activity and adherence to Mediterranean diet in DM2. Methods and analysis Study scope and population: The study will be conducted at ‘La Alamedilla’ primary care research unit in Salamanca (Spain). 200 patients with DM2 of both sexes, aged 25–70 years and who meet the inclusion criteria and sign the informed consent will be recruited. Each participant will attend the clinic at baseline and 3 and 12 months after intervention. Intervention Both groups will be given short advice on diet and physical activity. The intervention group will also take five heart-healthy walks and attend a group session on diet education and will be trained on use of an application for smartphone (EVIDENT II) for 3 months. Variables and measurement instruments The main study endpoints will be changes in physical activity, as assessed by a pedometer and the International Physical Activity Questionnaire, and adherence to the Mediterranean diet, as evaluated by an adherence questionnaire and the Diet Quality Index. Anthropometric parameters and laboratory values, lifestyles and quality of life will also be assessed. Ethics and dissemination It was approved by the Clinical Research Ethics Committee of Salamanca on 28/11/2016. Trial registration NCT02991079; Pre-results. PMID:28912193
Chang, John T; Morton, Sally C; Rubenstein, Laurence Z; Mojica, Walter A; Maglione, Margaret; Suttorp, Marika J; Roth, Elizabeth A; Shekelle, Paul G
2004-01-01
Objective To assess the relative effectiveness of interventions to prevent falls in older adults to either a usual care group or control group. Design Systematic review and meta-analyses. Data sources Medline, HealthSTAR, Embase, the Cochrane Library, other health related databases, and the reference lists from review articles and systematic reviews. Data extraction Components of falls intervention: multifactorial falls risk assessment with management programme, exercise, environmental modifications, or education. Results 40 trials were identified. A random effects analysis combining trials with risk ratio data showed a reduction in the risk of falling (risk ratio 0.88, 95% confidence interval 0.82 to 0.95), whereas combining trials with incidence rate data showed a reduction in the monthly rate of falling (incidence rate ratio 0.80, 0.72 to 0.88). The effect of individual components was assessed by meta-regression. A multifactorial falls risk assessment and management programme was the most effective component on risk of falling (0.82, 0.72 to 0.94, number needed to treat 11) and monthly fall rate (0.63, 0.49 to 0.83; 11.8 fewer falls in treatment group per 100 patients per month). Exercise interventions also had a beneficial effect on the risk of falling (0.86, 0.75 to 0.99, number needed to treat 16) and monthly fall rate (0.86, 0.73 to 1.01; 2.7). Conclusions Interventions to prevent falls in older adults are effective in reducing both the risk of falling and the monthly rate of falling. The most effective intervention was a multifactorial falls risk assessment and management programme. Exercise programmes were also effective in reducing the risk of falling. PMID:15031239
Ferrer, Assumpta; Formiga, Francesc; Sanz, Héctor; de Vries, Oscar J; Badia, Teresa; Pujol, Ramón
2014-01-01
Background The purpose of this study was to assess the effectiveness of a multifactorial intervention to reduce falls among the oldest-old people, including individuals with cognitive impairment or comorbidities. Methods A randomized, single-blind, parallel-group clinical trial was conducted from January 2009 to December 2010 in seven primary health care centers in Baix Llobregat (Barcelona). Of 696 referred people who were born in 1924, 328 were randomized to an intervention group or a control group. The intervention model used an algorithm and was multifaceted for both patients and their primary care providers. Primary outcomes were risk of falling and time until falls. Data analyses were by intention-to-treat. Results Sixty-five (39.6%) subjects in the intervention group and 48 (29.3%) in the control group fell during follow-up. The difference in the risk of falls was not significant (relative risk 1.28, 95% confidence interval [CI] 0.94–1.75). Cox regression models with time from randomization to the first fall were not significant. Cox models for recurrent falls showed that intervention had a negative effect (hazard ratio [HR] 1.46, 95% CI 1.03–2.09) and that functional impairment (HR 1.42, 95% CI 0.97–2.12), previous falls (HR 1.09, 95% CI 0.74–1.60), and cognitive impairment (HR 1.08, 95% CI 0.72–1.60) had no effect on the assessment. Conclusion This multifactorial intervention among octogenarians, including individuals with cognitive impairment or comorbidities, did not result in a reduction in falls. A history of previous falls, disability, and cognitive impairment had no effect on the program among the community-dwelling subjects in this study. PMID:24596458
Fogelfeld, Leon; Hart, Peter; Miernik, Jadwiga; Ko, Jocelyn; Calvin, Donna; Tahsin, Bettina; Adhami, Anwar; Mehrotra, Rajeev; Fogg, Louis
2017-03-01
To evaluate efficacy of a multifactorial-multidisciplinary approach in delaying CKD 3-4 progression to ESRD. Two-year proof-of-concept stratified randomized control trial conducted in an outpatient clinic of a large public hospital system. This intervention, led by a team of endocrinologists, nephrologists, nurse practitioners, and registered dietitians, integrated intensive diabetes-renal care with behavioral/dietary and pharmacological interventions. 120 low-income adults with T2DM and CKD 3-4 enrolled; 58% male, 55% African American, 23% Hispanic. Primary outcome was progression rate from CKD 3-4 to ESRD. Fewer intervention (13%) than control (28%) developed ESRD, p<0.05. Intervention had greater albumin/creatinine ratio (ACR) decrease (62% vs. 42%, p<0.05) and A1C<7% attainment (50% vs. 30%, p<0.05) and trended toward better lipid/blood pressure control (p=NS). Significant differences between 25 ESRD and 95 ESRD-free patients were baseline eGFR (28 vs. 40ml/min/1.73m 2 ), annual eGFR decline (15 vs. 3ml/min/year), baseline ACR (2362 vs. 1139mg/g), final ACR (2896 vs. 1201mg/g), and final A1C (6.9 vs. 7.8%). In multivariate Cox analysis, receiving the intervention reduced hazard ratio to develop ESRD (0.125, CI 0.029-0.54) as did higher baseline eGFR (0.69, CI 0.59-0.80). Greater annual eGFR decline increased hazard ratio (1.59, CI 1.34-1.87). The intervention delayed ESRD. Improved A1C and ACR plus not-yet-identified variables may have influenced better outcomes. Multifactorial-multidisciplinary care may serve as a CKD 3-4 treatment paradigm. Copyright © 2017 Elsevier Inc. All rights reserved.
Pladevall, Manel; Brotons, Carlos; Gabriel, Rafael; Arnau, Anna; Suarez, Carmen; de la Figuera, Mariano; Marquez, Emilio; Coca, Antonio; Sobrino, Javier; Divine, George; Heisler, Michele; Williams, L Keoki
2010-01-01
Background Medication non-adherence is common and results in preventable disease complications. This study assesses the effectiveness of a multifactorial intervention to improve both medication adherence and blood pressure control and to reduce cardiovascular events. Methods and Results In this multi-center, cluster-randomized trial, physicians from hospital-based hypertension clinics and primary care centers across Spain were randomized to receive and provide the intervention to their high-risk patients. Eligible patients were ≥50 years of age, had uncontrolled hypertension, and had an estimated 10-year cardiovascular risk greater than 30%. Physicians randomized to the intervention group counted patients’ pills, designated a family member to support adherence behavior, and provided educational information to patients. The primary outcome was blood pressure control at 6 months. Secondary outcomes included both medication adherence and a composite end-point of all cause mortality and cardiovascular-related hospitalizations. Seventy-nine physicians and 877 patients participated in the trial. The mean duration of follow-up was 39 months. Intervention patients were less likely to have an uncontrolled systolic blood pressure (odds ratio 0.62; 95% confidence interval [CI] 0.50–0.78) and were more likely to be adherent (OR 1.91; 95% CI 1.19–3.05) when compared with control group patients at 6 months. After five years 16% of the patients in the intervention group and 19% in the control group met the composite end-point (hazard ratio 0.97; 95% CI 0.67–1.39). Conclusions A multifactorial intervention to improve adherence to antihypertensive medication was effective in improving both adherence and blood pressure control, but it did not appear to improve long-term cardiovascular events. PMID:20823391
NASA Astrophysics Data System (ADS)
Singh, Sarvesh Kumar; Kumar, Pramod; Rani, Raj; Turbelin, Grégory
2017-04-01
The study highlights a theoretical comparison and various interpretations of a recent inversion technique, called renormalization, developed for the reconstruction of unknown tracer emissions from their measured concentrations. The comparative interpretations are presented in relation to the other inversion techniques based on principle of regularization, Bayesian, minimum norm, maximum entropy on mean, and model resolution optimization. It is shown that the renormalization technique can be interpreted in a similar manner to other techniques, with a practical choice of a priori information and error statistics, while eliminating the need of additional constraints. The study shows that the proposed weight matrix and weighted Gram matrix offer a suitable deterministic choice to the background error and measurement covariance matrices, respectively, in the absence of statistical knowledge about background and measurement errors. The technique is advantageous since it (i) utilizes weights representing a priori information apparent to the monitoring network, (ii) avoids dependence on background source estimates, (iii) improves on alternative choices for the error statistics, (iv) overcomes the colocalization problem in a natural manner, and (v) provides an optimally resolved source reconstruction. A comparative illustration of source retrieval is made by using the real measurements from a continuous point release conducted in Fusion Field Trials, Dugway Proving Ground, Utah.
Dentascan – Is the Investment Worth the Hype ???
Shah, Monali A; Shah, Sneha S; Dave, Deepak
2013-01-01
Background: Open Bone Measurement (OBM) and Bone Sounding (BS) are most reliable but invasive clinical methods for Alveolar Bone Level (ABL) assessment, causing discomfort to the patient. Routinely, IOPAs & OPGs are the commonest radiographic techniques used, which tend to underestimate bone loss and obscure buccal/lingual defects. Novel technique like dentascan (CBCT) eliminates this limitation by giving images in 3 planes – sagittal, coronal and axial. Aim: To compare & correlate non-invasive 3D radiographic technique of Dentascan with BS & OBM, and IOPA and OPG, in assessing the ABL. Settings and Design: Cross-sectional diagnostic study. Material and Methods: Two hundred and five sites were subjected to clinical and radiographic diagnostic techniques. Relative distance between the alveolar bone crest and reference wire was measured. All the measurements were compared and tested against the OBM. Statistical Analysis: Student’s t-test, ANOVA, Pearson correlation coefficient. Results: There is statistically significant difference between dentascan and OBM, only BS showed agreement with OBM (p < 0.05). Dentascan weakly correlated with OBM & BS lingually.Rest all techniques showed statistically significant difference between them (p= 0.00). Conclusion: Within the limitations of this study, only BS seems to be comparable with OBM with no superior result of Dentascan over the conventional techniques, except for lingual measurements. PMID:24551722
Sheikh, Adnan
2016-01-01
Objective: The aim of this study was to evaluate the impact of adaptive statistical iterative reconstruction (ASiR) technique on the image quality and radiation dose reduction. The comparison was made with the traditional filtered back projection (FBP) technique. Methods: We retrospectively reviewed 78 patients, who underwent cervical spine CT for blunt cervical trauma between 1 June 2010 and 30 November 2010. 48 patients were imaged using traditional FBP technique and the remaining 30 patients were imaged using the ASiR technique. The patient demographics, radiation dose, objective image signal and noise were recorded; while subjective noise, sharpness, diagnostic acceptability and artefacts were graded by two radiologists blinded to the techniques. Results: We found that the ASiR technique was able to reduce the volume CT dose index, dose–length product and effective dose by 36%, 36.5% and 36.5%, respectively, compared with the FBP technique. There was no significant difference in the image noise (p = 0.39), signal (p = 0.82) and signal-to-noise ratio (p = 0.56) between the groups. The subjective image quality was minimally better in the ASiR group but not statistically significant. There was excellent interobserver agreement on the subjective image quality and diagnostic acceptability for both groups. Conclusion: The use of ASiR technique allowed approximately 36% radiation dose reduction in the evaluation of cervical spine without degrading the image quality. Advances in knowledge: The present study highlights that the ASiR technique is extremely helpful in reducing the patient radiation exposure while maintaining the image quality. It is highly recommended to utilize this novel technique in CT imaging of different body regions. PMID:26882825
Patro, Satya N; Chakraborty, Santanu; Sheikh, Adnan
2016-01-01
The aim of this study was to evaluate the impact of adaptive statistical iterative reconstruction (ASiR) technique on the image quality and radiation dose reduction. The comparison was made with the traditional filtered back projection (FBP) technique. We retrospectively reviewed 78 patients, who underwent cervical spine CT for blunt cervical trauma between 1 June 2010 and 30 November 2010. 48 patients were imaged using traditional FBP technique and the remaining 30 patients were imaged using the ASiR technique. The patient demographics, radiation dose, objective image signal and noise were recorded; while subjective noise, sharpness, diagnostic acceptability and artefacts were graded by two radiologists blinded to the techniques. We found that the ASiR technique was able to reduce the volume CT dose index, dose-length product and effective dose by 36%, 36.5% and 36.5%, respectively, compared with the FBP technique. There was no significant difference in the image noise (p = 0.39), signal (p = 0.82) and signal-to-noise ratio (p = 0.56) between the groups. The subjective image quality was minimally better in the ASiR group but not statistically significant. There was excellent interobserver agreement on the subjective image quality and diagnostic acceptability for both groups. The use of ASiR technique allowed approximately 36% radiation dose reduction in the evaluation of cervical spine without degrading the image quality. The present study highlights that the ASiR technique is extremely helpful in reducing the patient radiation exposure while maintaining the image quality. It is highly recommended to utilize this novel technique in CT imaging of different body regions.
Testing prediction methods: Earthquake clustering versus the Poisson model
Michael, A.J.
1997-01-01
Testing earthquake prediction methods requires statistical techniques that compare observed success to random chance. One technique is to produce simulated earthquake catalogs and measure the relative success of predicting real and simulated earthquakes. The accuracy of these tests depends on the validity of the statistical model used to simulate the earthquakes. This study tests the effect of clustering in the statistical earthquake model on the results. Three simulation models were used to produce significance levels for a VLF earthquake prediction method. As the degree of simulated clustering increases, the statistical significance drops. Hence, the use of a seismicity model with insufficient clustering can lead to overly optimistic results. A successful method must pass the statistical tests with a model that fully replicates the observed clustering. However, a method can be rejected based on tests with a model that contains insufficient clustering. U.S. copyright. Published in 1997 by the American Geophysical Union.
UNCERTAINTY ON RADIATION DOSES ESTIMATED BY BIOLOGICAL AND RETROSPECTIVE PHYSICAL METHODS.
Ainsbury, Elizabeth A; Samaga, Daniel; Della Monaca, Sara; Marrale, Maurizio; Bassinet, Celine; Burbidge, Christopher I; Correcher, Virgilio; Discher, Michael; Eakins, Jon; Fattibene, Paola; Güçlü, Inci; Higueras, Manuel; Lund, Eva; Maltar-Strmecki, Nadica; McKeever, Stephen; Rääf, Christopher L; Sholom, Sergey; Veronese, Ivan; Wieser, Albrecht; Woda, Clemens; Trompier, Francois
2018-03-01
Biological and physical retrospective dosimetry are recognised as key techniques to provide individual estimates of dose following unplanned exposures to ionising radiation. Whilst there has been a relatively large amount of recent development in the biological and physical procedures, development of statistical analysis techniques has failed to keep pace. The aim of this paper is to review the current state of the art in uncertainty analysis techniques across the 'EURADOS Working Group 10-Retrospective dosimetry' members, to give concrete examples of implementation of the techniques recommended in the international standards, and to further promote the use of Monte Carlo techniques to support characterisation of uncertainties. It is concluded that sufficient techniques are available and in use by most laboratories for acute, whole body exposures to highly penetrating radiation, but further work will be required to ensure that statistical analysis is always wholly sufficient for the more complex exposure scenarios.
Simulation and statistics: Like rhythm and song
NASA Astrophysics Data System (ADS)
Othman, Abdul Rahman
2013-04-01
Simulation has been introduced to solve problems in the form of systems. By using this technique the following two problems can be overcome. First, a problem that has an analytical solution but the cost of running an experiment to solve is high in terms of money and lives. Second, a problem exists but has no analytical solution. In the field of statistical inference the second problem is often encountered. With the advent of high-speed computing devices, a statistician can now use resampling techniques such as the bootstrap and permutations to form pseudo sampling distribution that will lead to the solution of the problem that cannot be solved analytically. This paper discusses how a Monte Carlo simulation was and still being used to verify the analytical solution in inference. This paper also discusses the resampling techniques as simulation techniques. The misunderstandings about these two techniques are examined. The successful usages of both techniques are also explained.
da Silva, R C V; de Sá, C C; Pascual-Vaca, Á O; de Souza Fontes, L H; Herbella Fernandes, F A M; Dib, R A; Blanco, C R; Queiroz, R A; Navarro-Rodriguez, T
2013-07-01
The treatment of gastroesophageal reflux disease may be clinical or surgical. The clinical consists basically of the use of drugs; however, there are new techniques to complement this treatment, osteopathic intervention in the diaphragmatic muscle is one these. The objective of the study is to compare pressure values in the examination of esophageal manometry of the lower esophageal sphincter (LES) before and immediately after osteopathic intervention in the diaphragm muscle. Thirty-eight patients with gastroesophageal reflux disease - 16 submitted to sham technique and 22 submitted osteopathic technique - were randomly selected. The average respiratory pressure (ARP) and the maximum expiratory pressure (MEP) of the LES were measured by manometry before and after osteopathic technique at the point of highest pressure. Statistical analysis was performed using the Student's t-test and Mann-Whitney, and magnitude of the technique proposed was measured using the Cohen's index. Statistically significant difference in the osteopathic technique was found in three out of four in relation to the group of patients who performed the sham technique for the following measures of LES pressure: ARP with P= 0.027. The MEP had no statistical difference (P= 0.146). The values of Cohen d for the same measures were: ARP with d= 0.80 and MEP d= 0.52. Osteopathic manipulative technique produces a positive increment in the LES region soon after its performance. © 2012 Copyright the Authors. Journal compilation © 2012, Wiley Periodicals, Inc. and the International Society for Diseases of the Esophagus.
Vaidya, Sharad; Parkash, Hari; Bhargava, Akshay; Gupta, Sharad
2014-01-01
Abundant resources and techniques have been used for complete coverage crown fabrication. Conventional investing and casting procedures for phosphate-bonded investments require a 2- to 4-h procedure before completion. Accelerated casting techniques have been used, but may not result in castings with matching marginal accuracy. The study measured the marginal gap and determined the clinical acceptability of single cast copings invested in a phosphate-bonded investment with the use of conventional and accelerated methods. One hundred and twenty cast coping samples were fabricated using conventional and accelerated methods, with three finish lines: Chamfer, shoulder and shoulder with bevel. Sixty copings were prepared with each technique. Each coping was examined with a stereomicroscope at four predetermined sites and measurements of marginal gaps were documented for each. A master chart was prepared for all the data and was analyzed using Statistical Package for the Social Sciences version. Evidence of marginal gap was then evaluated by t-test. Analysis of variance and Post-hoc analysis were used to compare two groups as well as to make comparisons between three subgroups . Measurements recorded showed no statistically significant difference between conventional and accelerated groups. Among the three marginal designs studied, shoulder with bevel showed the best marginal fit with conventional as well as accelerated casting techniques. Accelerated casting technique could be a vital alternative to the time-consuming conventional casting technique. The marginal fit between the two casting techniques showed no statistical difference.
Data mining and statistical inference in selective laser melting
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kamath, Chandrika
Selective laser melting (SLM) is an additive manufacturing process that builds a complex three-dimensional part, layer-by-layer, using a laser beam to fuse fine metal powder together. The design freedom afforded by SLM comes associated with complexity. As the physical phenomena occur over a broad range of length and time scales, the computational cost of modeling the process is high. At the same time, the large number of parameters that control the quality of a part make experiments expensive. In this paper, we describe ways in which we can use data mining and statistical inference techniques to intelligently combine simulations andmore » experiments to build parts with desired properties. We start with a brief summary of prior work in finding process parameters for high-density parts. We then expand on this work to show how we can improve the approach by using feature selection techniques to identify important variables, data-driven surrogate models to reduce computational costs, improved sampling techniques to cover the design space adequately, and uncertainty analysis for statistical inference. Here, our results indicate that techniques from data mining and statistics can complement those from physical modeling to provide greater insight into complex processes such as selective laser melting.« less
Data mining and statistical inference in selective laser melting
Kamath, Chandrika
2016-01-11
Selective laser melting (SLM) is an additive manufacturing process that builds a complex three-dimensional part, layer-by-layer, using a laser beam to fuse fine metal powder together. The design freedom afforded by SLM comes associated with complexity. As the physical phenomena occur over a broad range of length and time scales, the computational cost of modeling the process is high. At the same time, the large number of parameters that control the quality of a part make experiments expensive. In this paper, we describe ways in which we can use data mining and statistical inference techniques to intelligently combine simulations andmore » experiments to build parts with desired properties. We start with a brief summary of prior work in finding process parameters for high-density parts. We then expand on this work to show how we can improve the approach by using feature selection techniques to identify important variables, data-driven surrogate models to reduce computational costs, improved sampling techniques to cover the design space adequately, and uncertainty analysis for statistical inference. Here, our results indicate that techniques from data mining and statistics can complement those from physical modeling to provide greater insight into complex processes such as selective laser melting.« less
Vexler, Albert; Tanajian, Hovig; Hutson, Alan D
In practice, parametric likelihood-ratio techniques are powerful statistical tools. In this article, we propose and examine novel and simple distribution-free test statistics that efficiently approximate parametric likelihood ratios to analyze and compare distributions of K groups of observations. Using the density-based empirical likelihood methodology, we develop a Stata package that applies to a test for symmetry of data distributions and compares K -sample distributions. Recognizing that recent statistical software packages do not sufficiently address K -sample nonparametric comparisons of data distributions, we propose a new Stata command, vxdbel, to execute exact density-based empirical likelihood-ratio tests using K samples. To calculate p -values of the proposed tests, we use the following methods: 1) a classical technique based on Monte Carlo p -value evaluations; 2) an interpolation technique based on tabulated critical values; and 3) a new hybrid technique that combines methods 1 and 2. The third, cutting-edge method is shown to be very efficient in the context of exact-test p -value computations. This Bayesian-type method considers tabulated critical values as prior information and Monte Carlo generations of test statistic values as data used to depict the likelihood function. In this case, a nonparametric Bayesian method is proposed to compute critical values of exact tests.
Playing at Statistical Mechanics
ERIC Educational Resources Information Center
Clark, Paul M.; And Others
1974-01-01
Discussed are the applications of counting techniques of a sorting game to distributions and concepts in statistical mechanics. Included are the following distributions: Fermi-Dirac, Bose-Einstein, and most probable. (RH)
Mechanisms and management of dry eye in cataract surgery patients.
Sutu, Christine; Fukuoka, Hideki; Afshari, Natalie A
2016-01-01
To provide a summary of the mechanisms that may cause dry eye after cataract surgery and discuss available and upcoming treatment modalities. Development or worsening of dry eye symptoms after cataract surgery is multifactorial with corneal nerve transection, inflammation, goblet cell loss, and meibomian gland dysfunction commonly cited as underlying disorders. With increasing awareness of the prevalence of dry eye disease, current surgical techniques are being analyzed for their contribution to the issue. Although many classic interventions, such as artificial tears and anti-inflammatory drops, remain first-line treatment options, they may not adequately address abnormalities of the tear film. The trend has been to create new drugs and technologies that target meibomian gland deficiencies and restore goblet cell numbers. Therapy for postoperative dry eye symptoms should be determined based on symptom severity and which underlying cause is most prominent at a given time. Patients with high-level risk factors for dry eye should be evaluated preoperatively to determine whether they have preexisting dry eye disease or if they are susceptible to developing disease after surgery.
Recent developments in the genetics of schizophrenia.
Shastry, B S
1999-09-01
Schizophrenia, which is also called "split personality," is a complex and multifactorial mental disorder with variable clinical manifestations. It perhaps represents several diseases and occurs throughout the world. It is a more-prevalent disorder among homeless people and is clinically characterized by hallucinations and delusions. The pathophysiology of schizophrenia is not localized to a single region of the brain and the etiology of this illness is not understood. Because of its complex pattern of inheritance, genetic techniques are not readily applicable in identifying the genes responsible for this disorder. Family, twin, and adoption studies, however, provide strong but indirect support for genetic components in the etiology of schizophrenia. Extensive linkage analyses now suggest that susceptibility genes may be present on chromosomes 5q, 6p, 8p, 13q, 18p, and 22q. Identification and characterization of these and other genes, as well as non-genetic factors, is one of the greatest challenges in biomedicine. This may ultimately lead to the development of a new line of effective and safe drugs or treatments for its prevention or cure.
Suárez, Manuel; Boqué, Noemí; del Bas, Josep M.; Arola, Lluís; Caimari, Antoni
2017-01-01
Non-alcoholic fatty liver disease (NAFLD) comprises a wide spectrum of hepatic disorders, from simple steatosis to hepatic necro-inflammation leading to non-alcoholic steatohepatitis (NASH). Although the prevalence of these multifactorial pathologies is continuously increasing in the population, there is still not an established methodology for their treatment other than weight loss and a change in lifestyle habits, such as a hypocaloric diet and physical exercise. In this framework, there is increasing evidence that several food bioactives and dietary patterns are effective for reversing and preventing the onset of these pathologies. Some studies have claimed that better responses are obtained when treatments are performed under a multifaceted approach, using different bioactive compounds that act against complementary targets. Thus, in this work, current strategies for treating NAFLD and NASH based on multi-ingredient-based supplements or the Mediterranean diet, a dietary pattern rich in bioactive compounds, are reviewed. Furthermore, the usefulness of omics techniques to design effective multi-ingredient nutritional interventions and to predict and monitor their response against these disorders is also discussed. PMID:28937599
Infectious complications after esophagectomy.
Neoral, Cestmir; Horakova, Martina; Aujesky, Rene; Chudacek, Josef; Hanulik, Vojtech; Chroma, Magdalena; Kolar, Milan
2012-06-01
Esophageal cancer is a serious diagnosis that has a relative incidence of 4/100,000 inhabitants in the Czech Republic. This disorder is managed predominantly by surgery. The steps to improving the outcome of treatment include a multifactorial approach. The role of operative technique in improving outcomes seems to have reached its limits. However, antibiotic prophylaxis and the treatment of complicating bacterial infections continue to play important roles. A total of 85 patients with strictly defined antibiotic prophylaxis during surgical esophagectomy were included in our study. Bacterial strains were isolated from the patient's clinical materials after operation; only one strain from each patient, the first to be isolated, was tested for antibiotic sensitivity. Infectious complications were observed in 15.3% of patients and the mortality rate from infectious complications reached 30.8%. The most frequently documented complicated infection was pneumonia (69.2%) and the most frequent pathogens were enteric bacteria (56.5%). Some bacterial strains producing extended-spectrum beta-lactamases and AmpC beta-lactamases were found. The infections in our patient set were of endogenous origin. In cases of pneumonia, it is appropriate to begin with antibiotics effective against enteric bacteria and Pseudomonas aeruginosa.
Predictors of asthma control in elderly patients.
Ban, Ga-Young; Trinh, Tu H K; Ye, Young-Min; Park, Hae-Sim
2016-06-01
We are in the era of rapid aging of the global population. Elderly asthmatic patients have an increased frequency of hospitalization and a high mortality rate. In this review, we focus on comorbidities and treatment issues in terms of the predictors of asthma control in the elderly. Some frequent comorbidities, such as chronic obstructive pulmonary disease, chronic sinusitis, obesity, and depression, are associated with uncontrolled asthma in elderly asthmatic patients. Smoking status in elderly asthmatic patients was associated with more frequent exacerbations. Management of comorbidities should be taken into account when we treat elderly asthmatic patients. Low treatment adherence, which is common in elderly asthmatic patients, predicts poor asthma control status. A poor knowledge about asthma, cognitive function impairment, and inappropriate inhaler technique result in low treatment adherence. Polypharmacy is associated with low treatment adherence, adverse drug reactions, and drug-drug interactions, and it is supposed to be a predictor of asthma control. Multifactorial assessments, including comorbidities, treatment adherence, and polypharmacy, are important for better asthma control in elderly asthmatic patients. Further studies on the strategy for the management of elderly asthmatic patients in a real-world setting are warranted.
Analyzing Faculty Salaries When Statistics Fail.
ERIC Educational Resources Information Center
Simpson, William A.
The role played by nonstatistical procedures, in contrast to multivariant statistical approaches, in analyzing faculty salaries is discussed. Multivariant statistical methods are usually used to establish or defend against prima facia cases of gender and ethnic discrimination with respect to faculty salaries. These techniques are not applicable,…
Explorations in Statistics: Correlation
ERIC Educational Resources Information Center
Curran-Everett, Douglas
2010-01-01
Learning about statistics is a lot like learning about science: the learning is more meaningful if you can actively explore. This sixth installment of "Explorations in Statistics" explores correlation, a familiar technique that estimates the magnitude of a straight-line relationship between two variables. Correlation is meaningful only when the…
Mining Internet search and social media for epidemiology
Many pervasive and multifactorial disorders of modern non-communicable and non-infectious diseases (i.e. obesity, asthma, migraine, autism) need to be better understood and explored. The cost of these disorders to the healthcare system and the general public’s quality of life are...
The etiology of digital dermatitis in ruminants: recent perspectives
USDA-ARS?s Scientific Manuscript database
Digital dermatitis is a multifactorial polymicrobial infectious disease originally described in dairy cattle but is increasingly recognized in beef cattle, sheep and more recently, elk. Clinical bovine lesions typically appear on the plantar surface of the hind foot from the interdigital space and h...
Marginal socio-economic effects of an employer's efforts to improve the work environment.
Rezagholi, Mahmoud
2018-01-01
Workplace health promotion (WHP) strongly requires the employer's efforts to improve the psychosocial, ergonomic, and physical environments of the workplace. There are many studies discussing the socio-economic advantage of WHP intervention programmes and thus the internal and external factors motivating employers to implement and integrate such programmes. However, the socio-economic impacts of the employer's multifactorial efforts to improve the work environment need to be adequately assessed. Data were collected from Swedish company Sandvik Materials Technology (SMT) through a work environment survey in April 2014. Different regression equations were analysed to assess marginal effects of the employer's efforts on overall labour effectiveness (OLE), informal work impairments (IWI), lost working hours (LWH), and labour productivity loss (LPL) in terms of money. The employer's multifactorial efforts resulted in increasing OLE, decreasing IWI and illness-related LWH, and cost savings in terms of decreasing LPL. Environmental factors at the workplace are the important determinant factor for OLE, and the latter is where socio-economic impacts of the employer's efforts primarily manifest.
Prolotherapy for Osteoarthritis and Tendinopathy: a Descriptive Review.
Rabago, David; Nourani, Bobby
2017-06-01
Osteoarthritis and overuse tendinopathy are common chronic conditions of high societal and patient burden. The precise etiology of pain and disability in both conditions is multifactorial and not well understood. Patients are often refractory to conservative therapy. The development of new therapeutic options in both conditions is a public health priority. Prolotherapy is an injection-based outpatient regenerative therapy for chronic musculoskeletal conditions, including osteoarthritis and tendinopathy. The authors reviewed the basic science and clinical literature associated with prolotherapy for these conditions. Systematic review, including meta-analysis, and randomized controlled trials suggest that prolotherapy may be associated with symptom improvement in mild to moderate symptomatic knee osteoarthritis and overuse tendinopathy. Although the mechanism of action is not well understood and is likely multifactorial, a growing body of literature suggests that prolotherapy for knee osteoarthritis may be appropriate for the treatment of symptoms associated with knee osteoarthritis in carefully selected patients who are refractory to conservative therapy and deserves further basic and clinical science investigation for the treatment of osteoarthritis and tendinopathy.
Segregation analysis reveals evidence of a major gene for Alzheimer disease.
Farrer, L A; Myers, R H; Connor, L; Cupples, L A; Growdon, J H
1991-01-01
In an attempt to resolve the relative influences of major genes, multifactorial heritability, and cohort effects on the susceptibility to Alzheimer disease (AD), complex segregation analysis was performed on 232 nuclear families. All families were consecutively ascertained through a single proband who was referred for diagnostic evaluation of a memory disorder. The results suggest that susceptibility to AD is determined, in part, by a major autosomal dominant allele with an additional multifactorial component. Single-locus, polygenic, sporadic, and no-transmission models, as well as recessive inheritance of the major effect, were significantly rejected. Excess transmission from the heterozygote was marginally significant and probably reflects the presence of phenocopies or perhaps the existence of two or more major loci for AD. The frequency of the AD susceptibility allele was estimated to be .038, but the major locus accounts for only 24% of the transmission variance, indicating a substantial role for other genetic and nongenetic mechanisms in the causation of AD. PMID:2035523
Ahonen, Cory L; Wasiuk, Anna; Fuse, Shinichiro; Turk, Mary Jo; Ernstoff, Marc S; Suriawinata, Arief A; Gorham, James D; Kedl, Ross M; Usherwood, Edward J; Noelle, Randolph J
2008-03-15
Identification of Toll-like receptors (TLRs) and their ligands, and tumor necrosis factor-tumor necrosis factor receptor (TNF-TNFR) pairs have provided the first logical, hypothesis-based strategies to molecularly concoct adjuvants to elicit potent cell-mediated immunity via activation of innate and adaptive immunity. However, isolated activation of one immune pathway in the absence of others can be toxic, ineffective, and detrimental to long-term, protective immunity. Effective engineered vaccines must include agents that trigger multiple immunologic pathways. Here, we report that combinatorial use of CD40 and TLR agonists as a cancer vaccine, compared with monotherapy, elicits high frequencies of self-reactive CD8(+) T cells, potent tumor-specific CD8(+) memory, CD8(+) T cells that efficiently infiltrate the tumor-burdened target organ; therapeutic efficacy; heightened ratios of CD8(+) T cells to FoxP3(+) cells at the tumor site; and reduced hepatotoxicity. These findings provide intelligent strategies for the formulation of multifactorial vaccines to achieve maximal efficacy in cancer vaccine trials in humans.
Daack-Hirsch, Sandra; Shah, Lisa L; Cady, Alyssa D
2018-03-01
Using the familial risk perception (FRP) model as a framework, we elicited causal and inheritance explanations for type 2 diabetes (T2D) from people who do not have T2D but have a family history for it. We identified four composite mental models for cause of T2D: (a) purely genetic; (b) purely behavioral/environmental; (c) direct multifactorial, in which risk factors interact and over time directly lead to T2D; and (d) indirect multifactorial, in which risk factors interact and over time cause a precursor health condition (such as obesity or metabolic syndrome) that leads to T2D. Interestingly, participants described specific risk factors such as genetics, food habits, lifestyle, weight, and culture as "running in the family." Our findings provide insight into lay beliefs about T2D that can be used by clinicians to anticipate or make sense of responses to questions they pose to patients about mental models for T2D.
Falls prevention in the elderly: translating evidence into practice.
Luk, James K H; Chan, T Y; Chan, Daniel K Y
2015-04-01
Falls are a common problem in the elderly. A common error in their management is that injury from the fall is treated, without finding its cause. Thus a proactive approach is important to screen for the likelihood of fall in the elderly. Fall assessment usually includes a focused history and a targeted examination. Timed up-and-go test can be performed quickly and is able to predict the likelihood of fall. Evidence-based fall prevention interventions include multi-component group or home-based exercises, participation in Tai Chi, environmental modifications, medication review, management of foot and footwear problems, vitamin D supplementation, and management of cardiovascular problems. If possible, these are best implemented in the form of multifactorial intervention. Bone health enhancement for residential care home residents and appropriate community patients, and prescription of hip protectors for residential care home residents are also recommended. Multifactorial intervention may also be useful in a hospital and residential care home setting. Use of physical restraints is not recommended for fall prevention.
[Analysis of etiological factors involved in noncarious cervical lesions].
Tomasik, Małgorzata
2006-01-01
The etiopathology of noncarious cervical lesions (NCCL) is multifactorial and still not fully understood. Tooth wear is defined as loss of dental hard tissue by a chemical or mechanical process that does not involve bacteria. This form of tooth surface loss includes attrition, abrasion, erosion, and abfraction. Noncarious cervical lesions represent loss of tooth structure at the cementoenamel junction. The purpose of this clinical study of NCCL was to analyze the etiology in relation to age and to identify the most important risk factors associated with cervical lesions, as well as patients and teeth more susceptible to NCCL with a focus on more effective treatment of this condition. The study group comprised 124 patients with NCCL, aged 15-75 years (mean = 44). A questionnaire was distributed addressing medical history--gastric disorders, dietary habits--consumption of acidic drinks, dental history, oral hygiene practices, and parafunctional habits. Clinical examination of tooth wear was performed on four tooth surfaces after air-drying. The distribution and severity of tooth wear was graded using the tooth wear index (TWI) calculated with a computer programme allowing for tooth characteristic to be determined for each decade of life. Depth of the cervical defect was measured with a periodontal probe. TWI was devised to reveal the extent of tooth surface wear irrespective of the cause. Raw scores were compared with the computer using predetermined threshold values which are set to distinguish between acceptable and unacceptable pathological levels of tooth wear for each decade of life and each tooth surface. Dentition status, oral hygiene, periodontal status, gingival recession, number of teeth and their mobility, oral symptoms of parafunction and relationship to lateral and protrusive tooth contact schemes was assessed and analyzed. Statistical analyses were performed with the Stata Statistical Software: release 5. The risk of NCCL formation was estimated with the logistic regression model. Results were presented as odds ratio, 95% confidence interval, and p probability. Tooth wear on all surfaces of the tooth, including cervical, was related to age and the ranges were 25-60%. Older patients were more likely to exhibit NCCL. Frequency, localization, and depth of noncarious cervical lesions in a given group of teeth was related to age, although NCCL was more common in premolars (mean = 85.1%). Associations between oral hygiene, consumption of acidic drinks, status of periodontium, number of teeth, their mobility and etiology of wedge-shaped defects were revealed. A relationship between lateral excursive contact of teeth, bruxism, and formation of cervical lesions was established evidencing a correlation between occlusal and cervical pathology. 1. Cervical lesions were most common in premolars. 2. Early detection of dental erosion is important for prevention of serious irreversible damage to dentition. 3. An understanding of the multifactorial nature of tooth wear and risk factors of erosion, abrasion, and ab-fraction is important in the patient's diagnostic protocol and management strategy.
Data Mining: Going beyond Traditional Statistics
ERIC Educational Resources Information Center
Zhao, Chun-Mei; Luan, Jing
2006-01-01
The authors provide an overview of data mining, giving special attention to the relationship between data mining and statistics to unravel some misunderstandings about the two techniques. (Contains 1 figure.)
Line identification studies using traditional techniques and wavelength coincidence statistics
NASA Technical Reports Server (NTRS)
Cowley, Charles R.; Adelman, Saul J.
1990-01-01
Traditional line identification techniques result in the assignment of individual lines to an atomic or ionic species. These methods may be supplemented by wavelength coincidence statistics (WCS). The strength and weakness of these methods are discussed using spectra of a number of normal and peculiar B and A stars that have been studied independently by both methods. The present results support the overall findings of some earlier studies. WCS would be most useful in a first survey, before traditional methods have been applied. WCS can quickly make a global search for all species and in this way may enable identifications of an unexpected spectrum that could easily be omitted entirely from a traditional study. This is illustrated by O I. WCS is a subject to well known weakness of any statistical technique, for example, a predictable number of spurious results are to be expected. The danger of small number statistics are illustrated. WCS is at its best relative to traditional methods in finding a line-rich atomic species that is only weakly present in a complicated stellar spectrum.
High order statistical signatures from source-driven measurements of subcritical fissile systems
NASA Astrophysics Data System (ADS)
Mattingly, John Kelly
1998-11-01
This research focuses on the development and application of high order statistical analyses applied to measurements performed with subcritical fissile systems driven by an introduced neutron source. The signatures presented are derived from counting statistics of the introduced source and radiation detectors that observe the response of the fissile system. It is demonstrated that successively higher order counting statistics possess progressively higher sensitivity to reactivity. Consequently, these signatures are more sensitive to changes in the composition, fissile mass, and configuration of the fissile assembly. Furthermore, it is shown that these techniques are capable of distinguishing the response of the fissile system to the introduced source from its response to any internal or inherent sources. This ability combined with the enhanced sensitivity of higher order signatures indicates that these techniques will be of significant utility in a variety of applications. Potential applications include enhanced radiation signature identification of weapons components for nuclear disarmament and safeguards applications and augmented nondestructive analysis of spent nuclear fuel. In general, these techniques expand present capabilities in the analysis of subcritical measurements.
Gene Identification Algorithms Using Exploratory Statistical Analysis of Periodicity
NASA Astrophysics Data System (ADS)
Mukherjee, Shashi Bajaj; Sen, Pradip Kumar
2010-10-01
Studying periodic pattern is expected as a standard line of attack for recognizing DNA sequence in identification of gene and similar problems. But peculiarly very little significant work is done in this direction. This paper studies statistical properties of DNA sequences of complete genome using a new technique. A DNA sequence is converted to a numeric sequence using various types of mappings and standard Fourier technique is applied to study the periodicity. Distinct statistical behaviour of periodicity parameters is found in coding and non-coding sequences, which can be used to distinguish between these parts. Here DNA sequences of Drosophila melanogaster were analyzed with significant accuracy.
Statistical innovations in the medical device world sparked by the FDA.
Campbell, Gregory; Yue, Lilly Q
2016-01-01
The world of medical devices while highly diverse is extremely innovative, and this facilitates the adoption of innovative statistical techniques. Statisticians in the Center for Devices and Radiological Health (CDRH) at the Food and Drug Administration (FDA) have provided leadership in implementing statistical innovations. The innovations discussed include: the incorporation of Bayesian methods in clinical trials, adaptive designs, the use and development of propensity score methodology in the design and analysis of non-randomized observational studies, the use of tipping-point analysis for missing data, techniques for diagnostic test evaluation, bridging studies for companion diagnostic tests, quantitative benefit-risk decisions, and patient preference studies.
Rule-based statistical data mining agents for an e-commerce application
NASA Astrophysics Data System (ADS)
Qin, Yi; Zhang, Yan-Qing; King, K. N.; Sunderraman, Rajshekhar
2003-03-01
Intelligent data mining techniques have useful e-Business applications. Because an e-Commerce application is related to multiple domains such as statistical analysis, market competition, price comparison, profit improvement and personal preferences, this paper presents a hybrid knowledge-based e-Commerce system fusing intelligent techniques, statistical data mining, and personal information to enhance QoS (Quality of Service) of e-Commerce. A Web-based e-Commerce application software system, eDVD Web Shopping Center, is successfully implemented uisng Java servlets and an Oracle81 database server. Simulation results have shown that the hybrid intelligent e-Commerce system is able to make smart decisions for different customers.
Effects of preprocessing Landsat MSS data on derived features
NASA Technical Reports Server (NTRS)
Parris, T. M.; Cicone, R. C.
1983-01-01
Important to the use of multitemporal Landsat MSS data for earth resources monitoring, such as agricultural inventories, is the ability to minimize the effects of varying atmospheric and satellite viewing conditions, while extracting physically meaningful features from the data. In general, the approaches to the preprocessing problem have been derived from either physical or statistical models. This paper compares three proposed algorithms; XSTAR haze correction, Color Normalization, and Multiple Acquisition Mean Level Adjustment. These techniques represent physical, statistical, and hybrid physical-statistical models, respectively. The comparisons are made in the context of three feature extraction techniques; the Tasseled Cap, the Cate Color Cube. and Normalized Difference.
A comparison of sequential and spiral scanning techniques in brain CT.
Pace, Ivana; Zarb, Francis
2015-01-01
To evaluate and compare image quality and radiation dose of sequential computed tomography (CT) examinations of the brain and spiral CT examinations of the brain imaged on a GE HiSpeed NX/I Dual Slice 2CT scanner. A random sample of 40 patients referred for CT examination of the brain was selected and divided into 2 groups. Half of the patients were scanned using the sequential technique; the other half were scanned using the spiral technique. Radiation dose data—both the computed tomography dose index (CTDI) and the dose length product (DLP)—were recorded on a checklist at the end of each examination. Using the European Guidelines on Quality Criteria for Computed Tomography, 4 radiologists conducted a visual grading analysis and rated the level of visibility of 6 anatomical structures considered necessary to produce images of high quality. The mean CTDI(vol) and DLP values were statistically significantly higher (P <.05) with the sequential scans (CTDI(vol): 22.06 mGy; DLP: 304.60 mGy • cm) than with the spiral scans (CTDI(vol): 14.94 mGy; DLP: 229.10 mGy • cm). The mean image quality rating scores for all criteria of the sequential scanning technique were statistically significantly higher (P <.05) in the visual grading analysis than those of the spiral scanning technique. In this local study, the sequential technique was preferred over the spiral technique for both overall image quality and differentiation between gray and white matter in brain CT scans. Other similar studies counter this finding. The radiation dose seen with the sequential CT scanning technique was significantly higher than that seen with the spiral CT scanning technique. However, image quality with the sequential technique was statistically significantly superior (P <.05).
Statistical characterization of short wind waves from stereo images of the sea surface
NASA Astrophysics Data System (ADS)
Mironov, Alexey; Yurovskaya, Maria; Dulov, Vladimir; Hauser, Danièle; Guérin, Charles-Antoine
2013-04-01
We propose a methodology to extract short-scale statistical characteristics of the sea surface topography by means of stereo image reconstruction. The possibilities and limitations of the technique are discussed and tested on a data set acquired from an oceanographic platform at the Black Sea. The analysis shows that reconstruction of the topography based on stereo method is an efficient way to derive non-trivial statistical properties of surface short- and intermediate-waves (say from 1 centimer to 1 meter). Most technical issues pertaining to this type of datasets (limited range of scales, lacunarity of data or irregular sampling) can be partially overcome by appropriate processing of the available points. The proposed technique also allows one to avoid linear interpolation which dramatically corrupts properties of retrieved surfaces. The processing technique imposes that the field of elevation be polynomially detrended, which has the effect of filtering out the large scales. Hence the statistical analysis can only address the small-scale components of the sea surface. The precise cut-off wavelength, which is approximatively half the patch size, can be obtained by applying a high-pass frequency filter on the reference gauge time records. The results obtained for the one- and two-points statistics of small-scale elevations are shown consistent, at least in order of magnitude, with the corresponding gauge measurements as well as other experimental measurements available in the literature. The calculation of the structure functions provides a powerful tool to investigate spectral and statistical properties of the field of elevations. Experimental parametrization of the third-order structure function, the so-called skewness function, is one of the most important and original outcomes of this study. This function is of primary importance in analytical scattering models from the sea surface and was up to now unavailable in field conditions. Due to the lack of precise reference measurements for the small-scale wave field, we could not quantify exactly the accuracy of the retrieval technique. However, it appeared clearly that the obtained accuracy is good enough for the estimation of second-order statistical quantities (such as the correlation function), acceptable for third-order quantities (such as the skwewness function) and insufficient for fourth-order quantities (such as kurtosis). Therefore, the stereo technique in the present stage should not be thought as a self-contained universal tool to characterize the surface statistics. Instead, it should be used in conjunction with other well calibrated but sparse reference measurement (such as wave gauges) for cross-validation and calibration. It then completes the statistical analysis in as much as it provides a snapshot of the three-dimensional field and allows for the evaluation of higher-order spatial statistics.
Resampling: A Marriage of Computers and Statistics. ERIC/TM Digest.
ERIC Educational Resources Information Center
Rudner, Lawrence M.; Shafer, Mary Morello
Advances in computer technology are making it possible for educational researchers to use simpler statistical methods to address a wide range of questions with smaller data sets and fewer, and less restrictive, assumptions. This digest introduces computationally intensive statistics, collectively called resampling techniques. Resampling is a…
ERIC Educational Resources Information Center
Foley, Gregory D.; Khoshaim, Heba Bakr; Alsaeed, Maha; Er, S. Nihan
2012-01-01
Attending professional development programmes can support teachers in applying new strategies for teaching mathematics and statistics. This study investigated (a) the extent to which the participants in a professional development programme subsequently used the techniques they had learned when teaching mathematics and statistics and (b) the…
Using Statistical Process Control to Make Data-Based Clinical Decisions.
ERIC Educational Resources Information Center
Pfadt, Al; Wheeler, Donald J.
1995-01-01
Statistical process control (SPC), which employs simple statistical tools and problem-solving techniques such as histograms, control charts, flow charts, and Pareto charts to implement continual product improvement procedures, can be incorporated into human service organizations. Examples illustrate use of SPC procedures to analyze behavioral data…
The Role of the Sampling Distribution in Understanding Statistical Inference
ERIC Educational Resources Information Center
Lipson, Kay
2003-01-01
Many statistics educators believe that few students develop the level of conceptual understanding essential for them to apply correctly the statistical techniques at their disposal and to interpret their outcomes appropriately. It is also commonly believed that the sampling distribution plays an important role in developing this understanding.…
Statistical Analysis For Nucleus/Nucleus Collisions
NASA Technical Reports Server (NTRS)
Mcguire, Stephen C.
1989-01-01
Report describes use of several statistical techniques to charactertize angular distributions of secondary particles emitted in collisions of atomic nuclei in energy range of 24 to 61 GeV per nucleon. Purpose of statistical analysis to determine correlations between intensities of emitted particles and angles comfirming existence of quark/gluon plasma.
Statistical iterative reconstruction to improve image quality for digital breast tomosynthesis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Xu, Shiyu, E-mail: shiyu.xu@gmail.com; Chen, Ying, E-mail: adachen@siu.edu; Lu, Jianping
2015-09-15
Purpose: Digital breast tomosynthesis (DBT) is a novel modality with the potential to improve early detection of breast cancer by providing three-dimensional (3D) imaging with a low radiation dose. 3D image reconstruction presents some challenges: cone-beam and flat-panel geometry, and highly incomplete sampling. A promising means to overcome these challenges is statistical iterative reconstruction (IR), since it provides the flexibility of accurate physics modeling and a general description of system geometry. The authors’ goal was to develop techniques for applying statistical IR to tomosynthesis imaging data. Methods: These techniques include the following: a physics model with a local voxel-pair basedmore » prior with flexible parameters to fine-tune image quality; a precomputed parameter λ in the prior, to remove data dependence and to achieve a uniform resolution property; an effective ray-driven technique to compute the forward and backprojection; and an oversampled, ray-driven method to perform high resolution reconstruction with a practical region-of-interest technique. To assess the performance of these techniques, the authors acquired phantom data on the stationary DBT prototype system. To solve the estimation problem, the authors proposed an optimization-transfer based algorithm framework that potentially allows fewer iterations to achieve an acceptably converged reconstruction. Results: IR improved the detectability of low-contrast and small microcalcifications, reduced cross-plane artifacts, improved spatial resolution, and lowered noise in reconstructed images. Conclusions: Although the computational load remains a significant challenge for practical development, the superior image quality provided by statistical IR, combined with advancing computational techniques, may bring benefits to screening, diagnostics, and intraoperative imaging in clinical applications.« less
Three-dimensional accuracy of different correction methods for cast implant bars
Kwon, Ji-Yung; Kim, Chang-Whe; Lim, Young-Jun; Kwon, Ho-Beom
2014-01-01
PURPOSE The aim of the present study was to evaluate the accuracy of three techniques for correction of cast implant bars. MATERIALS AND METHODS Thirty cast implant bars were fabricated on a metal master model. All cast implant bars were sectioned at 5 mm from the left gold cylinder using a disk of 0.3 mm thickness, and then each group of ten specimens was corrected by gas-air torch soldering, laser welding, and additional casting technique. Three dimensional evaluation including horizontal, vertical, and twisting measurements was based on measurement and comparison of (1) gap distances of the right abutment replica-gold cylinder interface at buccal, distal, lingual side, (2) changes of bar length, and (3) axis angle changes of the right gold cylinders at the step of the post-correction measurements on the three groups with a contact and non-contact coordinate measuring machine. One-way analysis of variance (ANOVA) and paired t-test were performed at the significance level of 5%. RESULTS Gap distances of the cast implant bars after correction procedure showed no statistically significant difference among groups. Changes in bar length between pre-casting and post-correction measurement were statistically significance among groups. Axis angle changes of the right gold cylinders were not statistically significance among groups. CONCLUSION There was no statistical significance among three techniques in horizontal, vertical and axial errors. But, gas-air torch soldering technique showed the most consistent and accurate trend in the correction of implant bar error. However, Laser welding technique, showed a large mean and standard deviation in vertical and twisting measurement and might be technique-sensitive method. PMID:24605205
Alkarkhi, Abbas F M; Ramli, Saifullah Bin; Easa, Azhar Mat
2009-01-01
Major (sodium, potassium, calcium, magnesium) and minor elements (iron, copper, zinc, manganese) and one heavy metal (lead) of Cavendish banana flour and Dream banana flour were determined, and data were analyzed using multivariate statistical techniques of factor analysis and discriminant analysis. Factor analysis yielded four factors explaining more than 81% of the total variance: the first factor explained 28.73%, comprising magnesium, sodium, and iron; the second factor explained 21.47%, comprising only manganese and copper; the third factor explained 15.66%, comprising zinc and lead; while the fourth factor explained 15.50%, comprising potassium. Discriminant analysis showed that magnesium and sodium exhibited a strong contribution in discriminating the two types of banana flour, affording 100% correct assignation. This study presents the usefulness of multivariate statistical techniques for analysis and interpretation of complex mineral content data from banana flour of different varieties.
Ariew, André
2007-03-01
Charles Darwin, James Clerk Maxwell, and Francis Galton were all aware, by various means, of Aldolphe Quetelet's pioneering work in statistics. Darwin, Maxwell, and Galton all had reason to be interested in Quetelet's work: they were all working on some instance of how large-scale regularities emerge from individual events that vary from one another; all were rejecting the divine interventionistic theories of their contemporaries; and Quetelet's techniques provided them with a way forward. Maxwell and Galton all explicitly endorse Quetelet's techniques in their work; Darwin does not incorporate any of the statistical ideas of Quetelet, although natural selection post-twentieth century synthesis has. Why not Darwin? My answer is that by the time Darwin encountered Malthus's law of excess reproduction he had all he needed to answer about large scale regularities in extinctions, speciation, and adaptation. He didn't need Quetelet.
Visualizing statistical significance of disease clusters using cartograms.
Kronenfeld, Barry J; Wong, David W S
2017-05-15
Health officials and epidemiological researchers often use maps of disease rates to identify potential disease clusters. Because these maps exaggerate the prominence of low-density districts and hide potential clusters in urban (high-density) areas, many researchers have used density-equalizing maps (cartograms) as a basis for epidemiological mapping. However, we do not have existing guidelines for visual assessment of statistical uncertainty. To address this shortcoming, we develop techniques for visual determination of statistical significance of clusters spanning one or more districts on a cartogram. We developed the techniques within a geovisual analytics framework that does not rely on automated significance testing, and can therefore facilitate visual analysis to detect clusters that automated techniques might miss. On a cartogram of the at-risk population, the statistical significance of a disease cluster is determinate from the rate, area and shape of the cluster under standard hypothesis testing scenarios. We develop formulae to determine, for a given rate, the area required for statistical significance of a priori and a posteriori designated regions under certain test assumptions. Uniquely, our approach enables dynamic inference of aggregate regions formed by combining individual districts. The method is implemented in interactive tools that provide choropleth mapping, automated legend construction and dynamic search tools to facilitate cluster detection and assessment of the validity of tested assumptions. A case study of leukemia incidence analysis in California demonstrates the ability to visually distinguish between statistically significant and insignificant regions. The proposed geovisual analytics approach enables intuitive visual assessment of statistical significance of arbitrarily defined regions on a cartogram. Our research prompts a broader discussion of the role of geovisual exploratory analyses in disease mapping and the appropriate framework for visually assessing the statistical significance of spatial clusters.
Childhood asthma is a multifactorial disease with a disturbingly high incidence in urbanized areas. The pathogenesis of asthma is poorly understood due to the complex relationship between genetic susceptibility and modulating environmental factors. The Mechanistic Indicators of C...
Autism Spectrum Disorders and Epigenetics
ERIC Educational Resources Information Center
Grafodatskaya, Daria; Chung, Brian; Szatmari, Peter; Weksberg, Rosanna
2010-01-01
Objective: Current research suggests that the causes of autism spectrum disorders (ASD) are multifactorial and include both genetic and environmental factors. Several lines of evidence suggest that epigenetics also plays an important role in ASD etiology and that it might, in fact, integrate genetic and environmental influences to dysregulate…
The Intergenerational Transmission of Parenting Styles of Irish Immigrant Mothers
ERIC Educational Resources Information Center
O'Brien, Helen G.
2010-01-01
The research on child developmental outcomes underscores the importance of exploring parenting styles and identifying their multifactorial and intergenerational influences. This descriptive study examined the individual parenting styles of a sample of 82 Irish immigrant mothers and investigated the factors that influenced their individual…
Autism Spectrum Disorders Associated with Chromosomal Abnormalities
ERIC Educational Resources Information Center
Lo-Castro, Adriana; Benvenuto, Arianna; Galasso, Cinzia; Porfirio, Cristina; Curatolo, Paolo
2010-01-01
Autism spectrum disorders (ASDs) constitute a class of severe neurodevelopmental conditions with complex multifactorial and heterogeneous etiology. Despite high estimates of heritability, genetic causes of ASDs remain elusive, due to a high degree of genetic and phenotypic heterogeneity. So far, several "monogenic" forms of autism have been…
By taking a multifactorial approach, the study will document complex aquatic plant responses to NPS nutrient contamination, providing fundamental insight into the broader impacts of environmental degradation, its impacts on plant function, and implications for ecosystem ser...
A Developmental-Genetic Model of Alcoholism: Implications for Genetic Research.
ERIC Educational Resources Information Center
Devor, Eric J.
1994-01-01
Research for biological-genetic markers of alcoholism is discussed in context of a multifactorial, heterogeneous, developmental model. Suggested that strategies used in linkage and association studies will require modification. Also suggested several extant associations of genetic markers represent true secondary interactive phenomena that alter…
Co-existent Presence of Alopecia Areata in Siblings: A Rare Presentation.
Mohanty, Sandip; Rohatgi, Pallavi C; Manchanda, Kajal
2014-04-01
Alopecia areata (AA) is a T cell mediated autoimmune disease with multifactorial etiology resulting in partial and total nonscarring alopecia. We hereby report a case of two brothers (aged 7 and 5 years) presenting with coincidental AA over scalp which is a rare presentation.
Moghe, Swapnil; Pillai, Ajay; Thomas, Shaji; Nair, Preeti P
2012-12-14
Salivary dysfunction may be due to systemic diseases and medications. The development of sialoliths is a multifactorial event in which disturbance in secretion, microliths and bacteria may play a major role. A case of sialolith in the parotid gland of a 25-year-old man, with no relevant medical history is reported here.
39 CFR 3050.1 - Definitions applicable to this part.
Code of Federal Regulations, 2011 CFR
2011-07-01
..., mathematical, or statistical theory, precept, or assumption applied by the Postal Service in producing a..., or statistical theory, precept, or assumption. A change in quantification technique should not change...
39 CFR 3050.1 - Definitions applicable to this part.
Code of Federal Regulations, 2013 CFR
2013-07-01
..., mathematical, or statistical theory, precept, or assumption applied by the Postal Service in producing a..., or statistical theory, precept, or assumption. A change in quantification technique should not change...
Suarez-Kurtz, Guilherme; Stenne, Raphaëlle; Somogyi, Andrew A.; Someya, Toshiyuki; Kayaalp, S. Oğuz; Kolker, Eugene
2009-01-01
Abstract Applications of omics technologies in the postgenomics era swiftly expanded from rare monogenic disorders to multifactorial common complex diseases, pharmacogenomics, and personalized medicine. Already, there are signposts indicative of further omics technology investment in nutritional sciences (nutrigenomics), environmental health/ecology (ecogenomics), and agriculture (agrigenomics). Genotype–phenotype association studies are a centerpiece of translational research in omics science. Yet scientific and ethical standards and ways to assess and communicate risk information obtained from association studies have been neglected to date. This is a significant gap because association studies decisively influence which genetic loci become genetic tests in the clinic or products in the genetic test marketplace. A growing challenge concerns the interpretation of large overlap typically observed in distribution of quantitative traits in a genetic association study with a polygenic/multifactorial phenotype. To remedy the shortage of risk assessment and communication tools for association studies, this paper presents the concept of edge effect. That is, the shift in population edges of a multifactorial quantitative phenotype is a more sensitive measure (than population averages) to gauge the population level impact and by extension, policy significance of an omics marker. Empirical application of the edge effect concept is illustrated using an original analysis of warfarin pharmacogenomics and the VKORC1 genetic variation in a Brazilian population sample. These edge effect analyses are examined in relation to regulatory guidance development for association studies. We explain that omics science transcends the conventional laboratory bench space and includes a highly heterogeneous cast of stakeholders in society who have a plurality of interests that are often in conflict. Hence, communication of risk information in diagnostic medicine also demands attention to processes involved in production of knowledge and human values embedded in scientific practice, for example, why, how, by whom, and to what ends association studies are conducted, and standards are developed (or not). To ensure sustainability of omics innovations and forecast their trajectory, we need interventions to bridge the gap between omics laboratory and society. Appreciation of scholarship in history of omics science is one remedy to responsibly learn from the past to ensure a sustainable future in omics fields, both emerging (nutrigenomics, ecogenomics), and those that are more established (pharmacogenomics). Another measure to build public trust and sustainability of omics fields could be legislative initiatives to create a multidisciplinary oversight body, at arm's length from conflict of interests, to carry out independent, impartial, and transparent innovation analyses and prospective technology assessment. PMID:19290811
Ozdemir, Vural; Suarez-Kurtz, Guilherme; Stenne, Raphaëlle; Somogyi, Andrew A; Someya, Toshiyuki; Kayaalp, S Oğuz; Kolker, Eugene
2009-02-01
Applications of omics technologies in the postgenomics era swiftly expanded from rare monogenic disorders to multifactorial common complex diseases, pharmacogenomics, and personalized medicine. Already, there are signposts indicative of further omics technology investment in nutritional sciences (nutrigenomics), environmental health/ecology (ecogenomics), and agriculture (agrigenomics). Genotype-phenotype association studies are a centerpiece of translational research in omics science. Yet scientific and ethical standards and ways to assess and communicate risk information obtained from association studies have been neglected to date. This is a significant gap because association studies decisively influence which genetic loci become genetic tests in the clinic or products in the genetic test marketplace. A growing challenge concerns the interpretation of large overlap typically observed in distribution of quantitative traits in a genetic association study with a polygenic/multifactorial phenotype. To remedy the shortage of risk assessment and communication tools for association studies, this paper presents the concept of edge effect. That is, the shift in population edges of a multifactorial quantitative phenotype is a more sensitive measure (than population averages) to gauge the population level impact and by extension, policy significance of an omics marker. Empirical application of the edge effect concept is illustrated using an original analysis of warfarin pharmacogenomics and the VKORC1 genetic variation in a Brazilian population sample. These edge effect analyses are examined in relation to regulatory guidance development for association studies. We explain that omics science transcends the conventional laboratory bench space and includes a highly heterogeneous cast of stakeholders in society who have a plurality of interests that are often in conflict. Hence, communication of risk information in diagnostic medicine also demands attention to processes involved in production of knowledge and human values embedded in scientific practice, for example, why, how, by whom, and to what ends association studies are conducted, and standards are developed (or not). To ensure sustainability of omics innovations and forecast their trajectory, we need interventions to bridge the gap between omics laboratory and society. Appreciation of scholarship in history of omics science is one remedy to responsibly learn from the past to ensure a sustainable future in omics fields, both emerging (nutrigenomics, ecogenomics), and those that are more established (pharmacogenomics). Another measure to build public trust and sustainability of omics fields could be legislative initiatives to create a multidisciplinary oversight body, at arm's length from conflict of interests, to carry out independent, impartial, and transparent innovation analyses and prospective technology assessment.
2010-01-01
Background Earlier diagnosis followed by multi-factorial cardiovascular risk intervention may improve outcomes in Type 2 Diabetes Mellitus (T2DM). Latent phase identification through screening requires structured, appropriately targeted population-based approaches. Providers responsible for implementing screening policy await evidence of clinical and cost effectiveness from randomised intervention trials in screen-detected T2DM cases. UK South Asians are at particularly high risk of abnormal glucose tolerance and T2DM. To be effective national screening programmes must achieve good coverage across the population by identifying barriers to the detection of disease and adapting to the delivery of earlier care. Here we describe the rationale and methods of a systematic community screening programme and randomised controlled trial of cardiovascular risk management within a UK multiethnic setting (ADDITION-Leicester). Design A single-blind cluster randomised, parallel group trial among people with screen-detected T2DM comparing a protocol driven intensive multi-factorial treatment with conventional care. Methods ADDITION-Leicester consists of community-based screening and intervention phases within 20 general practices coordinated from a single academic research centre. Screening adopts a universal diagnostic approach via repeated 75g-Oral Glucose Tolerance Tests within an eligible non-diabetic population of 66,320 individuals aged 40-75 years (25-75 years South Asian). Volunteers also provide detailed medical and family histories; complete health questionnaires, undergo anthropometric measures, lipid profiling and a proteinuria assessment. Primary outcome is reduction in modelled Coronary Heart Disease (UKPDS CHD) risk at five years. Seven thousand (30% of South Asian ethnic origin) volunteers over three years will be recruited to identify a screen-detected T2DM cohort (n = 285) powered to detected a 6% relative difference (80% power, alpha 0.05) between treatment groups at one year. Randomisation will occur at practice-level with newly diagnosed T2DM cases receiving either conventional (according to current national guidelines) or intensive (algorithmic target-driven multi-factorial cardiovascular risk intervention) treatments. Discussion ADDITION-Leicester is the largest multiethnic (targeting >30% South Asian recruitment) community T2DM and vascular risk screening programme in the UK. By assessing feasibility and efficacy of T2DM screening, it will inform national disease prevention policy and contribute significantly to our understanding of the health care needs of UK South Asians. Trial registration Clinicaltrial.gov (NCT00318032). PMID:20170482
Barry, R J
1993-01-01
Two apparently new effects in human cardiac responding, "primary bradycardia" and "vagal inhibition", were first described by the Laceys. These effects have been considered by some researchers to reflect differential cardiac innervation, analogous to similar effects observed in animal preparations with direct vagal stimulation. However, it has been argued that such effects arise merely from the data-analytic techniques introduced by the Laceys, and hence are not genuine cardiac cycle effects. Jennings, van der Molen, Somsen and Ridderinkhoff (Psychophysiology, 28 (1991) 596-606) recently proposed a plotting technique and statistical procedure in an attempt to resolve this issue. The present paper demonstrates that the plotting technique fails to achieve their stated aim, since it identifies data from identical cardiac responses as showing cardiac-cycle effects. In addition, the statistical procedure is shown to be reducible to a trivial test of response occurrence. The implication of these demonstrations, in the context of other work, is that this area of investigation has reached a dead end.
Statistical Techniques for Assessing water‐quality effects of BMPs
Walker, John F.
1994-01-01
Little has been published on the effectiveness of various management practices in small rural lakes and streams at the watershed scale. In this study, statistical techniques were used to test for changes in water‐quality data from watersheds where best management practices (BMPs) were implemented. Reductions in data variability due to climate and seasonality were accomplished through the use of regression methods. This study discusses the merits of using storm‐mass‐transport data as a means of improving the ability to detect BMP effects on stream‐water quality. Statistical techniques were applied to suspended‐sediment records from three rural watersheds in Illinois for the period 1981–84. None of the techniques identified changes in suspended sediment, primarily because of the small degree of BMP implementation and because of potential errors introduced through the estimation of storm‐mass transport. A Monte Carlo sensitivity analysis was used to determine the level of discrete change that could be detected for each watershed. In all cases, the use of regressions improved the ability to detect trends.Read More: http://ascelibrary.org/doi/abs/10.1061/(ASCE)0733-9437(1994)120:2(334)
Application of multivariate statistical techniques in microbial ecology.
Paliy, O; Shankar, V
2016-03-01
Recent advances in high-throughput methods of molecular analyses have led to an explosion of studies generating large-scale ecological data sets. In particular, noticeable effect has been attained in the field of microbial ecology, where new experimental approaches provided in-depth assessments of the composition, functions and dynamic changes of complex microbial communities. Because even a single high-throughput experiment produces large amount of data, powerful statistical techniques of multivariate analysis are well suited to analyse and interpret these data sets. Many different multivariate techniques are available, and often it is not clear which method should be applied to a particular data set. In this review, we describe and compare the most widely used multivariate statistical techniques including exploratory, interpretive and discriminatory procedures. We consider several important limitations and assumptions of these methods, and we present examples of how these approaches have been utilized in recent studies to provide insight into the ecology of the microbial world. Finally, we offer suggestions for the selection of appropriate methods based on the research question and data set structure. © 2016 John Wiley & Sons Ltd.
The applications of statistical quantification techniques in nanomechanics and nanoelectronics.
Mai, Wenjie; Deng, Xinwei
2010-10-08
Although nanoscience and nanotechnology have been developing for approximately two decades and have achieved numerous breakthroughs, the experimental results from nanomaterials with a higher noise level and poorer repeatability than those from bulk materials still remain as a practical issue, and challenge many techniques of quantification of nanomaterials. This work proposes a physical-statistical modeling approach and a global fitting statistical method to use all the available discrete data or quasi-continuous curves to quantify a few targeted physical parameters, which can provide more accurate, efficient and reliable parameter estimates, and give reasonable physical explanations. In the resonance method for measuring the elastic modulus of ZnO nanowires (Zhou et al 2006 Solid State Commun. 139 222-6), our statistical technique gives E = 128.33 GPa instead of the original E = 108 GPa, and unveils a negative bias adjustment f(0). The causes are suggested by the systematic bias in measuring the length of the nanowires. In the electronic measurement of the resistivity of a Mo nanowire (Zach et al 2000 Science 290 2120-3), the proposed new method automatically identified the importance of accounting for the Ohmic contact resistance in the model of the Ohmic behavior in nanoelectronics experiments. The 95% confidence interval of resistivity in the proposed one-step procedure is determined to be 3.57 +/- 0.0274 x 10( - 5) ohm cm, which should be a more reliable and precise estimate. The statistical quantification technique should find wide applications in obtaining better estimations from various systematic errors and biased effects that become more significant at the nanoscale.
Mendoza, Roger Lee
2018-06-13
We review clinical evidence of therapeutic efficacy and effectiveness of omega-3 fatty acids (omega-3s) in keratoconjunctivitis sicca, colloquially known as dry eye disease. In doing so, we identify relevant literature to address the following questions: (1) What definitive guidance can clinical evidence offer eye physicians and their patients? (2) What aspects of omega-3 supplementation lack definitive evidence, and how might economic assessments help? A targeted and systematic search strategy based on PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) was designed in this study for refereed clinical trials of omega-3s in dry eye treatment. Four key databases were accessed. Records were filtered through a three-step process using predetermined inclusion criteria. Data was extracted for experimental design, sample population characteristics, content of test and control groups, symptoms and associated opthalmologic conditions, diagnostic measures, patient health outcomes, adverse events, and model time horizon. A total of 219 records were initially identified, of which 21 prospective clinical trials, with a total of 2,973 participants, were admitted for review. Clinical evidence indicates that daily oral supplementation with omega-3s statistically correlates with dry eye treatment in the general symptomatic population as well as induced sub-populations. Reported adverse events are minimal. These trials nonetheless exhibit considerable heterogeneity in clinical endpoints, particularly as a result of the multi-factorial character of dry eye as well as continuous advances in scientific knowledge and technology. Their findings and recommendations appear to be of limited external validity. And causal inferences are needed, but difficult to establish. These have encouraged and sustained wide variations in ophthalmologic practice and normative decision-making. Comparability of omega-3 therapeutic efficacy and effectiveness remains a major challenge in dry eye disease management. Notwithstanding its multi-factorial character, addressing prevailing methodological and empirical issues in clinical trials will help reduce knowledge gaps and normative choices among eye physicians and patients alike. In this regard, pharmacoeconomics offers a useful and robust toolset through which analysis of cost-minimization, cost-effectiveness, and cost-utility as well as meta-analysis can be comparatively pursued. Blending measures of costs and outcomes puts in perspective the heterogeneity of clinical endpoints in keratoconjunctivitis sicca.
A constant current charge technique for low Earth orbit life testing
NASA Technical Reports Server (NTRS)
Glueck, Peter
1991-01-01
A constant current charge technique for low earth orbit testing of nickel cadmium cells is presented. The method mimics the familiar taper charge of the constant potential technique while maintaining cell independence for statistical analysis. A detailed example application is provided and the advantages and disadvantages of this technique are discussed.
Weak value amplification considered harmful
NASA Astrophysics Data System (ADS)
Ferrie, Christopher; Combes, Joshua
2014-03-01
We show using statistically rigorous arguments that the technique of weak value amplification does not perform better than standard statistical techniques for the tasks of parameter estimation and signal detection. We show that using all data and considering the joint distribution of all measurement outcomes yields the optimal estimator. Moreover, we show estimation using the maximum likelihood technique with weak values as small as possible produces better performance for quantum metrology. In doing so, we identify the optimal experimental arrangement to be the one which reveals the maximal eigenvalue of the square of system observables. We also show these conclusions do not change in the presence of technical noise.
The Malpractice of Statistical Interpretation
ERIC Educational Resources Information Center
Fraas, John W.; Newman, Isadore
1978-01-01
Problems associated with the use of gain scores, analysis of covariance, multicollinearity, part and partial correlation, and the lack of rectilinearity in regression are discussed. Particular attention is paid to the misuse of statistical techniques. (JKS)
Applying Regression Analysis to Problems in Institutional Research.
ERIC Educational Resources Information Center
Bohannon, Tom R.
1988-01-01
Regression analysis is one of the most frequently used statistical techniques in institutional research. Principles of least squares, model building, residual analysis, influence statistics, and multi-collinearity are described and illustrated. (Author/MSE)
42 CFR 1003.109 - Notice of proposed determination.
Code of Federal Regulations, 2010 CFR
2010-10-01
... briefly describe the statistical sampling technique utilized by the Inspector General); (3) The reason why... statistical sampling in accordance with § 1003.133 in which case the notice shall describe those claims and...
11 CFR 9036.4 - Commission review of submissions.
Code of Federal Regulations, 2010 CFR
2010-01-01
..., in conducting its review, may utilize statistical sampling techniques. Based on the results of its... nonmatchable and the reason that it is not matchable; or if statistical sampling is used, the estimated amount...
STATISTICAL SAMPLING AND DATA ANALYSIS
Research is being conducted to develop approaches to improve soil and sediment sampling techniques, measurement design and geostatistics, and data analysis via chemometric, environmetric, and robust statistical methods. Improvements in sampling contaminated soil and other hetero...
NASA Astrophysics Data System (ADS)
Richfield, Jon; bookfeller
2016-07-01
In reply to Ralph Kenna and Pádraig Mac Carron's feature article “Maths meets myths” in which they describe how they are using techniques from statistical physics to characterize the societies depicted in ancient Icelandic sagas.
Wavelet analysis in ecology and epidemiology: impact of statistical tests
Cazelles, Bernard; Cazelles, Kévin; Chavez, Mario
2014-01-01
Wavelet analysis is now frequently used to extract information from ecological and epidemiological time series. Statistical hypothesis tests are conducted on associated wavelet quantities to assess the likelihood that they are due to a random process. Such random processes represent null models and are generally based on synthetic data that share some statistical characteristics with the original time series. This allows the comparison of null statistics with those obtained from original time series. When creating synthetic datasets, different techniques of resampling result in different characteristics shared by the synthetic time series. Therefore, it becomes crucial to consider the impact of the resampling method on the results. We have addressed this point by comparing seven different statistical testing methods applied with different real and simulated data. Our results show that statistical assessment of periodic patterns is strongly affected by the choice of the resampling method, so two different resampling techniques could lead to two different conclusions about the same time series. Moreover, our results clearly show the inadequacy of resampling series generated by white noise and red noise that are nevertheless the methods currently used in the wide majority of wavelets applications. Our results highlight that the characteristics of a time series, namely its Fourier spectrum and autocorrelation, are important to consider when choosing the resampling technique. Results suggest that data-driven resampling methods should be used such as the hidden Markov model algorithm and the ‘beta-surrogate’ method. PMID:24284892
Wavelet analysis in ecology and epidemiology: impact of statistical tests.
Cazelles, Bernard; Cazelles, Kévin; Chavez, Mario
2014-02-06
Wavelet analysis is now frequently used to extract information from ecological and epidemiological time series. Statistical hypothesis tests are conducted on associated wavelet quantities to assess the likelihood that they are due to a random process. Such random processes represent null models and are generally based on synthetic data that share some statistical characteristics with the original time series. This allows the comparison of null statistics with those obtained from original time series. When creating synthetic datasets, different techniques of resampling result in different characteristics shared by the synthetic time series. Therefore, it becomes crucial to consider the impact of the resampling method on the results. We have addressed this point by comparing seven different statistical testing methods applied with different real and simulated data. Our results show that statistical assessment of periodic patterns is strongly affected by the choice of the resampling method, so two different resampling techniques could lead to two different conclusions about the same time series. Moreover, our results clearly show the inadequacy of resampling series generated by white noise and red noise that are nevertheless the methods currently used in the wide majority of wavelets applications. Our results highlight that the characteristics of a time series, namely its Fourier spectrum and autocorrelation, are important to consider when choosing the resampling technique. Results suggest that data-driven resampling methods should be used such as the hidden Markov model algorithm and the 'beta-surrogate' method.
Statistical process management: An essential element of quality improvement
NASA Astrophysics Data System (ADS)
Buckner, M. R.
Successful quality improvement requires a balanced program involving the three elements that control quality: organization, people and technology. The focus of the SPC/SPM User's Group is to advance the technology component of Total Quality by networking within the Group and by providing an outreach within Westinghouse to foster the appropriate use of statistic techniques to achieve Total Quality. SPM encompasses the disciplines by which a process is measured against its intrinsic design capability, in the face of measurement noise and other obscuring variability. SPM tools facilitate decisions about the process that generated the data. SPM deals typically with manufacturing processes, but with some flexibility of definition and technique it accommodates many administrative processes as well. The techniques of SPM are those of Statistical Process Control, Statistical Quality Control, Measurement Control, and Experimental Design. In addition, techniques such as job and task analysis, and concurrent engineering are important elements of systematic planning and analysis that are needed early in the design process to ensure success. The SPC/SPM User's Group is endeavoring to achieve its objectives by sharing successes that have occurred within the member's own Westinghouse department as well as within other US and foreign industry. In addition, failures are reviewed to establish lessons learned in order to improve future applications. In broader terms, the Group is interested in making SPM the accepted way of doing business within Westinghouse.
Interpolative modeling of GaAs FET S-parameter data bases for use in Monte Carlo simulations
NASA Technical Reports Server (NTRS)
Campbell, L.; Purviance, J.
1992-01-01
A statistical interpolation technique is presented for modeling GaAs FET S-parameter measurements for use in the statistical analysis and design of circuits. This is accomplished by interpolating among the measurements in a GaAs FET S-parameter data base in a statistically valid manner.
ERIC Educational Resources Information Center
Hardy, Melissa
2005-01-01
This article presents a response to Timothy Patrick Moran's article "The Sociology of Teaching Graduate Statistics." In his essay, Moran argues that exciting developments in techniques of quantitative analysis are currently coupled with a much less exciting formulaic approach to teaching sociology graduate students about quantitative analysis. The…
NCES Handbook of Survey Methods. NCES 2011-609
ERIC Educational Resources Information Center
Burns, Shelley, Ed.; Wang, Xiaolei, Ed.; Henning, Alexandra, Ed.
2011-01-01
Since its inception, the National Center for Education Statistics (NCES) has been committed to the practice of documenting its statistical methods for its customers and of seeking to avoid misinterpretation of its published data. The reason for this policy is to assure customers that proper statistical standards and techniques have been observed,…
Applying Statistical Process Quality Control Methodology to Educational Settings.
ERIC Educational Resources Information Center
Blumberg, Carol Joyce
A subset of Statistical Process Control (SPC) methodology known as Control Charting is introduced. SPC methodology is a collection of graphical and inferential statistics techniques used to study the progress of phenomena over time. The types of control charts covered are the null X (mean), R (Range), X (individual observations), MR (moving…
Statistics for People Who (Think They) Hate Statistics. Third Edition
ERIC Educational Resources Information Center
Salkind, Neil J.
2007-01-01
This text teaches an often intimidating and difficult subject in a way that is informative, personable, and clear. The author takes students through various statistical procedures, beginning with correlation and graphical representation of data and ending with inferential techniques and analysis of variance. In addition, the text covers SPSS, and…
ERIC Educational Resources Information Center
Theoret, Julie M.; Luna, Andrea
2009-01-01
This action research combined qualitative and quantitative techniques to investigate two different types of writing assignments in an introductory undergraduate statistics course. The assignments were written in response to the same set of prompts but in two different ways: homework journal assignments or initial posts to a computer discussion…
Imura, N; Kato, A S; Novo, N F; Hata, G; Uemura, M; Toda, T
2001-10-01
The purpose of this study was to compare the effects of two engine-driven, nickel-titanium instrument systems with hand files in the final shape of slight and moderately curved canals. A total of 72 mesial roots of extracted human mandibular molars were divided into three groups: ProFile .04 taper, Pow-R rotary systems, and Flex-R hand-filing technique. The roots were mounted and cross-sectioned at two different horizontal levels using a modified Bramante technique. Pre- and postinstrumented cross-sectional roots were imaged, recorded, and computer analyzed. Results showed that, at the middle third, in almost all groups, there was a tendency of cutting more toward the mesial side with only one exception: Pow-R cut more to the distal side (danger zone) (p < 0.02). At the apical third, Flex-R (p < 0.03) and ProFile (0.001) transported to the mesial side (danger zone) when the curvature increased. When the three techniques were compared analyzing each side and considering the two groups of curvature, at the middle third in the moderately curved-canal group, Flex-R cut statistically more than Pow-R toward the lingual side. The other comparisons showed no statistically significant difference. When the techniques were compared in relation with the degree of curvature, in the apical third, ProFile .04 cut statistically more toward the mesial side in the moderately curved canal group than in the slightly curved canal group. The other comparisons showed no statistically significant difference. Canal preparation time was shorter with hand instrumentation (p < .05) in a few instances.
[Digital radiography in young children. Considerations based on experiences in practice].
Berkhout, W E R; Mileman, P A; Weerheijm, K L
2004-10-01
In dentistry, digital radiology techniques, such as a charge-coupled device and a storage phosphor plate, are gaining popularity. It was the objective of this study to assess the importance of the advantages and disadvantages of digital radiology techniques for bitewing radiography in young children, when compared to conventional film. A group of dentists received a questionnaire regarding their experiences with digital radiology techniques or conventional films among young children. Using the Simple Multi-Attributive Rating Technique (SMART) a final weighted score was calculated for the charge-coupled device, the phosphor plate, and conventional film. The scores were 7.40, 7.38, and 6.98 respectively. The differences were not statistically significant (p > 0.47). It could be concluded that, on the basis of experiences in practice, there are no statistically significant preferences for the use of digital radioogy techniques for bitewing radiography in young children.
Lightweight and Statistical Techniques for Petascale PetaScale Debugging
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miller, Barton
2014-06-30
This project investigated novel techniques for debugging scientific applications on petascale architectures. In particular, we developed lightweight tools that narrow the problem space when bugs are encountered. We also developed techniques that either limit the number of tasks and the code regions to which a developer must apply a traditional debugger or that apply statistical techniques to provide direct suggestions of the location and type of error. We extend previous work on the Stack Trace Analysis Tool (STAT), that has already demonstrated scalability to over one hundred thousand MPI tasks. We also extended statistical techniques developed to isolate programming errorsmore » in widely used sequential or threaded applications in the Cooperative Bug Isolation (CBI) project to large scale parallel applications. Overall, our research substantially improved productivity on petascale platforms through a tool set for debugging that complements existing commercial tools. Previously, Office Of Science application developers relied either on primitive manual debugging techniques based on printf or they use tools, such as TotalView, that do not scale beyond a few thousand processors. However, bugs often arise at scale and substantial effort and computation cycles are wasted in either reproducing the problem in a smaller run that can be analyzed with the traditional tools or in repeated runs at scale that use the primitive techniques. New techniques that work at scale and automate the process of identifying the root cause of errors were needed. These techniques significantly reduced the time spent debugging petascale applications, thus leading to a greater overall amount of time for application scientists to pursue the scientific objectives for which the systems are purchased. We developed a new paradigm for debugging at scale: techniques that reduced the debugging scenario to a scale suitable for traditional debuggers, e.g., by narrowing the search for the root-cause analysis to a small set of nodes or by identifying equivalence classes of nodes and sampling our debug targets from them. We implemented these techniques as lightweight tools that efficiently work on the full scale of the target machine. We explored four lightweight debugging refinements: generic classification parameters, such as stack traces, application-specific classification parameters, such as global variables, statistical data acquisition techniques and machine learning based approaches to perform root cause analysis. Work done under this project can be divided into two categories, new algorithms and techniques for scalable debugging, and foundation infrastructure work on our MRNet multicast-reduction framework for scalability, and Dyninst binary analysis and instrumentation toolkits.« less
Multifactorial antimicrobial wood protectants
Robert D. Coleman; Carol A. Clausen
2008-01-01
It is unlikely that a single antimicrobial compound, whether synthetic or natural, will provide the âmagic bulletâ for eliminating multiple biological agents affecting wood products. Development of synergistic combinations of selected compounds, especially those derived from natural sources, is recognized as a promising approach to improved wood protection. Recent...
Modem methods in molecular biology and advanced computational tools show promise in elucidating complex interactions that occur between genes and environmental factors in diseases such as asthma. However, appropriately designed studies are critical for these methods to reach the...
Increased Serum Levels of Epidermal Growth Factor in Children with Autism
ERIC Educational Resources Information Center
Iseri, Elvan; Guney, Esra; Ceylan, Mehmet F.; Yucel, Aysegul; Aral, Arzu; Bodur, Sahin; Sener, Sahnur
2011-01-01
The etiology of autism is unclear, however autism is considered as a multifactorial disorder that is influenced by neurological, environmental, immunological and genetic factors. Growth factors, including epidermal growth factor (EGF), play an important role in the celluler proliferation and the differentiation of the central and peripheral…
Variables Affecting Emerging Adults' Self-Reported Risk and Reckless Behaviors
ERIC Educational Resources Information Center
Duangpatra, Krisna N. K.; Bradley, Graham L.; Glendon, A. Ian
2009-01-01
Young adults' behaviors are frequently characterized by risk-taking and recklessness. Few studies have examined the correlates of risk and reckless behaviors in emerging adults. Drawing on theories emphasising multifactorial effects of personality, social, and cognitive variables, this study explores psychosocial factors contributing to risk and…
Aetiology of Autism: Findings and Questions
ERIC Educational Resources Information Center
Rutter, M.
2005-01-01
Background Although there is good evidence that autism is a multifactorial disorder, an adequate understanding of the genetic and non-genetic causes has yet to be achieved. Methods Empirical research findings and conceptual reviews are reviewed with respect to evidence on possible causal influences. Results Much the strongest evidence concerns the…
Acute and chronic effects of transportation stress in the honey bee, Apis mellifera
USDA-ARS?s Scientific Manuscript database
Owing to the continued impact of colony collapse disorder (CCD) on the beekeeping industry, numerous stressors including nutrition, pests and pathogens and biocides are being investigated as potential contributors to what appears to be a multi-factorial disorder. Because honey bee hives are transpo...
Association of Autism Spectrum Disorders and Inflammatory Bowel Disease
ERIC Educational Resources Information Center
Lee, Maunoo; Krishnamurthy, Jayasree; Susi, Apryl; Sullivan, Carolyn; Gorman, Gregory H.; Hisle-Gorman, Elizabeth; Erdie-Lalena, Christine R.; Nylund, Cade M.
2018-01-01
Autism spectrum disorders (ASD) and inflammatory bowel disease (IBD) both have multifactorial pathogenesis with an increasing number of studies demonstrating gut-brain associations. We aim to examine the association between ASD and IBD using strict classification criteria for IBD. We conducted a retrospective case-cohort study using records from…
USDA-ARS?s Scientific Manuscript database
Bovine respiratory disease complex (BRDC) is a multifactorial disease caused by complex interactions among viral and bacterial pathogens, stressful management practices and host genetic variability. Although vaccines and antibiotic treatments are readily available to prevent and treat infection caus...
Parents Psychopathology of Children with Attention Deficit Hyperactivity Disorder
ERIC Educational Resources Information Center
Margari, Francesco; Craig, Francesco; Petruzzelli, Maria Giuseppina; Lamanna, Annalinda; Matera, Emilia; Margari, Lucia
2013-01-01
Attention Deficit Hyperactivity Disorder (ADHD) is a disorder with extremely complex etiology, not yet well defined but certainly multi-factorial. This study investigated the possible etiopathogenetic role of ADHD symptoms and psychopathology disorders in parents of children with ADHD. We present a case-control study of parents of 50 children…
The volatilization of SPLAT® for use in pheromone mating disruption of cranberry pests
USDA-ARS?s Scientific Manuscript database
The paraffin-based pheromone carrier, SPLAT, was tested for its volatilization rate. A multi-factorial study was initiated to examine the interactive effects of point-source size, shape, and duration. The study showed that tremendous amounts of the pheromone were released early, followed by a gradua...
Foreign-Accented Speech Perception Ratings: A Multifactorial Case Study
ERIC Educational Resources Information Center
Kraut, Rachel; Wulff, Stefanie
2013-01-01
Seventy-eight native English speakers rated the foreign-accented speech (FAS) of 24 international students enrolled in an Intensive English programme at a public university in Texas on degree of accent, comprehensibility and communicative ability. Variables considered to potentially impact listeners' ratings were the sex of the speaker, the first…
Moghe, Swapnil; Pillai, Ajay; Thomas, Shaji; Nair, Preeti P
2012-01-01
Salivary dysfunction may be due to systemic diseases and medications. The development of sialoliths is a multifactorial event in which disturbance in secretion, microliths and bacteria may play a major role. A case of sialolith in the parotid gland of a 25-year-old man, with no relevant medical history is reported here. PMID:23242089
Engaging Community-Based Organizations in Fall Prevention Education
ERIC Educational Resources Information Center
Kramer, B. Josea; Vivrette, Rebecca L.; Rubenstein, Laurence Z.
2011-01-01
Falls are a major public health problem for older adults, and community-based organizations play a key role in educating seniors about falls prevention (FP). We conducted a qualitative process evaluation at six sites to report community-based centers' perspectives on adoption, adaptation, and sustainability of an evidence-based multifactorial FP…
USDA-ARS?s Scientific Manuscript database
Diet-induced milk fat depression (MFD) is a multifactorial condition resulting from the interaction of numerous risk factors including diet fermentability and unsaturated fatty acids (FA) concentration, feed additives, and individual cow effects. 2-hydroxy-4-(methylthio)butanoate (HMTBa) is a methio...