444 results match your criteria clustered binary

GEECORR: A SAS macro for regression models of correlated binary responses and within-cluster correlation using generalized estimating equations.

Comput Methods Programs Biomed 2021 Jul 14;208:106276. Epub 2021 Jul 14.

Lexitas Pharma Services, Inc., Durham, NC 27701-2102, United States. Electronic address:

Background And Objectives: Generalized estimating equations (GEE) provide population-averaged model inference for longitudinal and clustered outcomes via a generalized linear model for the effect of explanatory variables on the marginal mean, while intra-cluster correlations are ordinarily treated as nuisance parameters. Software to richly parameterize and conduct inference for complex correlation structures in the marginal modeling framework is scarce.

Methods: A SAS macro, GEECORR, has been developed for the analysis of clustered binary data based on GEE to include additional estimating equations for modeling pairwise correlation between binary variates as a function of covariates. Read More

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Consequences of ignoring clustering in linear regression.

BMC Med Res Methodol 2021 Jul 7;21(1):139. Epub 2021 Jul 7.

Medical Research Council Lifecourse Epidemiology Unit, University of Southampton, Southampton, UK.

Background: Clustering of observations is a common phenomenon in epidemiological and clinical research. Previous studies have highlighted the importance of using multilevel analysis to account for such clustering, but in practice, methods ignoring clustering are often employed. We used simulated data to explore the circumstances in which failure to account for clustering in linear regression could lead to importantly erroneous conclusions. Read More

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Risk prediction in multicentre studies when there is confounding by cluster or informative cluster size.

BMC Med Res Methodol 2021 Jul 4;21(1):135. Epub 2021 Jul 4.

Department of Statistical Science, UCL, London, UK.

Background: Clustered data arise in research when patients are clustered within larger units. Generalised Estimating Equations (GEE) and Generalised Linear Models (GLMM) can be used to provide marginal and cluster-specific inference and predictions, respectively.

Methods: Confounding by Cluster (CBC) and Informative cluster size (ICS) are two complications that may arise when modelling clustered data. Read More

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Association of intracluster correlation measures with outcome prevalence for binary outcomes in cluster randomised trials.

Stat Methods Med Res 2021 Jul 4:9622802211026004. Epub 2021 Jul 4.

Université de Tours, Université de Nantes, INSERM, Tours, France.

In cluster randomised trials, a measure of intracluster correlation such as the intraclass correlation coefficient (ICC) should be reported for each primary outcome. Providing intracluster correlation estimates may help in calculating sample size of future cluster randomised trials and also in interpreting the results of the trial from which they are derived. For a binary outcome, the ICC is known to be associated with its prevalence, which raises at least two issues. Read More

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Habitat Characteristics as Potential Drivers of the Infection in European Badger () Populations.

Pathogens 2021 Jun 7;10(6). Epub 2021 Jun 7.

Institute of Wildlife Management and Wildlife Biology, Faculty of Forestry, University of Sopron, H-9400 Sopron, Hungary.

From 2016 to 2020, an investigation was carried out to identify the rate of spp. infections in European badgers in Hungary. During the study, the hearts and lungs of 50 animals were dissected in order to collect adult worms, the morphometrical characteristics of which were used for species identification. Read More

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Prevalence of lead toxicity in adolescents in Kuwait.

BMC Public Health 2021 06 22;21(1):1189. Epub 2021 Jun 22.

Department of Food Science and Nutrition, College of Life Sciences, Kuwait University, Box 5969, 13060, Safat, Kuwait.

Background: Elevated blood lead level (EBLL) is a public health problem in both developing and industrialized countries. Being a petrochemical-based economy, lead (Pb) levels are expected to be high in Kuwait, but systematic data on population exposure are lacking. This study aimed at determining the prevalence of EBLL in adolescents in Kuwait. Read More

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Hospital Food Experience Questionnaire (HFEQ): Reliable, valid and predicts food intake in adult patients.

Clin Nutr 2021 Jun 3;40(6):4011-4021. Epub 2021 May 3.

Department of Kinesiology, University of Waterloo, 200 University Ave W, Waterloo, ON, N2L 3G1, Canada; Schlegel-UW Research Institute for Aging, 250 Laurelwood Dr, Waterloo, ON, N2J 0E2, Canada. Electronic address:

Background & Aims: Low food intake is a primary contributor to iatrogenic hospital malnutrition and can be influenced by perceptions of poor food quality. Valid and reliable tools to assess the food experience of hospital patients are lacking. This study aimed to determine the internal reliability, convergent construct and predictive validity of the new Hospital Food Experience Questionnaire (HFEQ) and to methodically derive and test a shortened version of the questionnaire (HFEQ-sv). Read More

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CRISPR/Cas9-induced β-carotene hydroxylase mutation in Dunaliella salina CCAP19/18.

AMB Express 2021 Jun 7;11(1):83. Epub 2021 Jun 7.

Medical College, Henan University of Chinese Medicine, Zhengzhou, 450046, Henan, China.

Dunaliella salina (D. salina) has been exploited as a novel expression system for the field of genetic engineering. However, owing to the low or inconsistent expression of target proteins, it has been greatly restricted to practical production of recombinant proteins. Read More

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Clustering of HIV Patients in Ethiopia.

HIV AIDS (Auckl) 2021 25;13:581-592. Epub 2021 May 25.

University of Gondar, College of Natural and Computational Science, Departmentof Statistics, Gondar, Ethiopia.

Background: Among the many worldwide health problems, HIV/AIDS has caused severe health problems in several countries. The problem is also widely seen in Ethiopia. The general objective of the study is to cluster HIV patients and to find out the factors that mostly affect the prevalence of HIV within a group (cluster) and between groups (clusters) of HIV patients. Read More

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Variable selection methods for identifying predictor interactions in data with repeatedly measured binary outcomes.

J Clin Transl Sci 2020 Nov 16;5(1):e59. Epub 2020 Nov 16.

Department of Medicine, Division of Rheumatology and Immunology, Medical University of South Carolina, Charleston, SC, USA.

Introduction: Identifying predictors of patient outcomes evaluated over time may require modeling interactions among variables while addressing within-subject correlation. Generalized linear mixed models (GLMMs) and generalized estimating equations (GEEs) address within-subject correlation, but identifying interactions can be difficult if not hypothesized . We evaluate the performance of several variable selection approaches for clustered binary outcomes to provide guidance for choosing between the methods. Read More

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November 2020

Prevalence and Molecular Characterization of in Cattle, Goats, and Horses in the Republic of Korea.

Vector Borne Zoonotic Dis 2021 Jul 12;21(7):502-508. Epub 2021 Apr 12.

Department of Animal Science and Biotechnology and College of Ecology and Environmental Science, Kyungpook National University, Sangju, Republic of Korea.

is an obligate intracellular zoonotic bacterium with a global distribution. This study was conducted to investigate the prevalence of in different animals and to assess the potential role of these species as reservoirs of infection and transmission to humans. A total of 592 blood samples (105 beef cattle, 61 dairy cattle, 110 Korean native goats, 83 Boer goats, and 233 horses) were collected in the Republic of Korea (ROK). Read More

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Inference in skew generalized t-link models for clustered binary outcome via a parameter-expanded EM algorithm.

PLoS One 2021 6;16(4):e0249604. Epub 2021 Apr 6.

Laboratoire de Biomathématiques et d'Estimations Forestières, Faculté des Sciences Agronomiques, Université d'Abomey-Calavi, Abomey-Calavi, Bénin.

Binary Generalized Linear Mixed Model (GLMM) is the most common method used by researchers to analyze clustered binary data in biological and social sciences. The traditional approach to GLMMs causes substantial bias in estimates due to steady shape of logistic and normal distribution assumptions thereby resulting into wrong and misleading decisions. This study brings forward an approach governed by skew generalized t distributions that belong to a class of potentially skewed and heavy tailed distributions. Read More

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Alternatives to Logistic Regression Models when Analyzing Cluster Randomized Trials with Binary Outcomes.

Francis L Huang

Prev Sci 2021 Apr 6. Epub 2021 Apr 6.

Department of Educational, School, and Counseling Psychology, University of Missouri, 16 Hill Hall, Columbia, MO, 65211, USA.

Binary outcomes are often encountered when analyzing cluster randomized trials (CRTs). A common approach to obtaining the average treatment effect of an intervention may involve using a logistic regression model. We outline some interpretive and statistical challenges associated with using logistic regression and discuss two alternative/supplementary approaches for analyzing clustered data with binary outcomes: the linear probability model (LPM) and the modified Poisson regression model. Read More

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Predictors of New-Onset Epilepsy in People With Younger-Onset Neurocognitive Disorders.

Front Aging Neurosci 2021 16;13:637260. Epub 2021 Mar 16.

Department of Neuroscience, The Central Clinical School, Monash University, Melbourne, VIC, Australia.

People with neurocognitive disorders (NCDs) have an increased risk of epilepsy. However, most studies investigating the risk of seizures in people with NCDs are limited to those with Alzheimer's disease (AD) and vascular dementia (VD), and those who developed dementia after age 65 years. A knowledge gap exists regarding factors associated with development of epilepsy in people with younger-onset NCD, and those with non-AD and non-VD dementia subtypes. Read More

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Revealing New Candidate Genes for Teat Number Relevant Traits in Duroc Pigs Using Genome-Wide Association Studies.

Animals (Basel) 2021 Mar 13;11(3). Epub 2021 Mar 13.

Key Laborary of Animal Genetics, Breeding and Reproduction (Poultry) of Ministry of Agriculture, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China.

The number of teats is related to the nursing ability of sows. In the present study, we conducted genome-wide association studies (GWAS) for traits related to teat number in Duroc pig population. Two mixed models, one for counted and another for binary phenotypic traits, were employed to analyze seven traits: the right (RTN), left (LTN), and total (TTN) teat numbers; maximum teat number on a side (MAX); left minus right side teat number (LR); the absolute value of LR (ALR); and the presence of symmetry between left and right teat numbers (SLR). Read More

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The Evolutionary Stage of Cognitive Frailty and Its Changing Characteristics in Old Adults.

J Nutr Health Aging 2021 ;25(4):467-478

Jiao Lu, Shanxi Medical University, No. 56, Xinjian South Road, Box No. 1042, 030001, Taiyuan, Shanxi, China, Tel: +86 13100096395, Email:

Objectives: This study aimed to explore the evolutionary stage of the elderly from the normal to the cognitive frailty, and to identify the important factors which influenced the changes of the cognitive frailty stage from the «physiological-psychological-social» perspective.

Design: A cross-sectional study.

Setting And Participants: A random cluster sampling was used to recruit 4,010 old adults living in community from Shanxi province in China. Read More

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Spatial skew-normal/independent models for nonrandomly missing clustered data.

Stat Med 2021 06 29;40(13):3085-3105. Epub 2021 Mar 29.

Departament of Statistics, University of Connecticut, Storrs, Connecticut, USA.

Clinical studies on periodontal disease (PD) often lead to data collected which are clustered in nature (viz. clinical attachment level, or CAL, measured at tooth-sites and clustered within subjects) that are routinely analyzed under a linear mixed model framework, with underlying normality assumptions of the random effects and random errors. However, a careful look reveals that these data might exhibit skewness and tail behavior, and hence the usual normality assumptions might be questionable. Read More

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A random forest method with feature selection for developing medical prediction models with clustered and longitudinal data.

J Biomed Inform 2021 05 26;117:103763. Epub 2021 Mar 26.

Department of Biostatistics and Data Science, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA. Electronic address:

Background: Machine learning methodologies are gaining popularity for developing medical prediction models for datasets with a large number of predictors, particularly in the setting of clustered and longitudinal data. Binary Mixed Model (BiMM) forest is a promising machine learning algorithm which may be applied to develop prediction models for clustered and longitudinal binary outcomes. Although machine learning methods for clustered and longitudinal methods such as BiMM forest exist, feature selection has not been analyzed via data simulations. Read More

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Influencing Indicators and Spatial Variation of Diabetes Mellitus Prevalence in Shandong, China: A Framework for Using Data-Driven and Spatial Methods.

Geohealth 2021 Mar 1;5(3):e2020GH000320. Epub 2021 Mar 1.

School of Resource and Environmental Sciences Wuhan University Wuhan China.

To control and prevent the risk of diabetes, diabetes studies have identified the need to better understand and evaluate the associations between influencing indicators and the prevalence of diabetes. One constraint has been that influencing indicators have been selected mainly based on subjective judgment and tested using traditional statistical modeling methods. We proposed a framework new to diabetes studies using data-driven and spatial methods to identify the most significant influential determinants of diabetes automatically and estimated their relationships. Read More

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External parameter orthogonalization-support vector machine for processing of attenuated total reflectance-mid-infrared spectra: A solution for saffron authenticity problem.

Anal Chim Acta 2021 Apr 11;1154:338308. Epub 2021 Feb 11.

Department of Chemistry, Sharif University of Technology, Tehran, Iran. Electronic address:

In the present work, a new approach based on external parameter orthogonalization combined with support vector machine (EPO-SVM) is proposed for processing of attenuated total reflectance-Fourier transform mid-infrared (ATR-FT-MIR) spectra with the goal of solving authentication problem in saffron, the most expensive spice in the world. First, one-hundred authentic saffron samples are clustered by principal component analysis (PCA) with EPO as the best preprocessing strategy. Then, EPO-SVM is used for the detection of four commonly used plant-derived adulterants (i. Read More

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Molecular characterization of Clostridioides difficile ribotype 027 in a major Chinese hospital.

J Microbiol Immunol Infect 2021 Jan 28. Epub 2021 Jan 28.

Department of Laboratory Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China. Electronic address:

Background: The rapid spread of C. difficile 027 has become one of the leading threats of healthcare-associated infections wordwild. However, C. Read More

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January 2021

Prognostic value of tumor metabolic imaging phenotype by FDG PET radiomics in HNSCC.

Ann Nucl Med 2021 Mar 8;35(3):370-377. Epub 2021 Feb 8.

Division of Nuclear Medicine, Department of Radiology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, South Korea.

Objective: Tumor metabolic phenotype can be assessed with integrated image pattern analysis of F-fluoro-deoxy-glucose (FDG) Positron Emission Tomography/Computed Tomography (PET/CT), called radiomics. This study was performed to assess the prognostic value of radiomics PET parameters in head and neck squamous cell carcinoma (HNSCC) patients.

Methods: F-fluoro-deoxy-glucose (FDG) PET/CT data of 215 patients from HNSCC collection free database in The Cancer Imaging Archive (TCIA), and 122 patients in Seoul St. Read More

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Host transcriptional response to TB preventive therapy differentiates two sub-groups of IGRA-positive individuals.

Tuberculosis (Edinb) 2021 03 28;127:102033. Epub 2020 Nov 28.

Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel St, London, WC1E 7HT, UK; TB Centre, London School of Hygiene and Tropical Medicine, Keppel St, London, WC1E 7HT, UK.

We hypothesised that individuals with immunological sensitisation to Mycobacterium tuberculosis (Mtb), conventionally regarded as evidence of latent tuberculosis infection (LTBI), would demonstrate binary responses to preventive therapy (PT), reflecting the differential immunological consequences of the sterilisation of viable infection in those with active Mtb infection versus no Mtb killing in those who did not harbour viable bacilli. We investigated longitudinal whole blood transcriptional profile responses to PT of Interferon gamma release assay (IGRA)-positive tuberculosis contacts and IGRA-negative, tuberculosis-unexposed controls. Longitudinal unsupervised clustering analysis with a subset of 474 most variable genes in antigen-stimulated blood separated the IGRA-positive participants into two distinct subgroups, one of which clustered with the IGRA-negative controls. Read More

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Satellite data and machine learning reveal the incidence of late frost defoliations on Iberian beech forests.

Ecol Appl 2021 04 22;31(3):e02288. Epub 2021 Feb 22.

Department of Computer Architecture and Technology, Universidad Politécnica de Madrid, Boadilla del Monte, E-28660, Spain.

Climate warming is driving an advance of leaf unfolding date in temperate deciduous forests, promoting longer growing seasons and higher carbon gains. However, an earlier leaf phenology also increases the risk of late frost defoliation (LFD) events. Compiling the spatiotemporal patterns of defoliations caused by spring frost events is critical to unveil whether the balance between the current advance in leaf unfolding dates and the frequency of LFD occurrence is changing and represents a threaten for the future viability and persistence of deciduous forests. Read More

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Topological Analysis of the Language Networks of Ancient Traditional Chinese Medicine Books.

Evid Based Complement Alternat Med 2020 10;2020:8810016. Epub 2020 Dec 10.

Beijing Key Lab of Traffic Data Analysis and Mining, School of Computer and Information Technology, Beijing Jiaotong University, Beijing 100044, China.

This study aims to explore the topological regularities of the character network of ancient traditional Chinese medicine (TCM) book. We applied the 2-gram model to construct language networks from ancient TCM books. Each text of the book was separated into sentences and a TCM book was generated as a directed network, in which nodes represent Chinese characters and links represent the sequential associations between Chinese characters in the sentences (the occurrence of identical sequential associations is considered as the weight of this link). Read More

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December 2020

Phylogenomics of 8,839 Clostridioides difficile genomes reveals recombination-driven evolution and diversification of toxin A and B.

PLoS Pathog 2020 12 28;16(12):e1009181. Epub 2020 Dec 28.

Department of Biology, David R. Cheriton School of Computer Science, and Waterloo Centre for Microbial Research, University of Waterloo, Waterloo, Ontario, Canada.

Clostridioides difficile is the major worldwide cause of antibiotic-associated gastrointestinal infection. A pathogenicity locus (PaLoc) encoding one or two homologous toxins, toxin A (TcdA) and toxin B (TcdB), is essential for C. difficile pathogenicity. Read More

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December 2020

Variable selection in social-environmental data: sparse regression and tree ensemble machine learning approaches.

BMC Med Res Methodol 2020 12 10;20(1):302. Epub 2020 Dec 10.

Cancer Prevention and Control, Fox Chase Cancer Center, Young Pavilion, 333 Cottman Ave, Philadelphia, PA, 19111, USA.

Background: Social-environmental data obtained from the US Census is an important resource for understanding health disparities, but rarely is the full dataset utilized for analysis. A barrier to incorporating the full data is a lack of solid recommendations for variable selection, with researchers often hand-selecting a few variables. Thus, we evaluated the ability of empirical machine learning approaches to identify social-environmental factors having a true association with a health outcome. Read More

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December 2020

Prevalence of pregnancy-related complications and associated factors among reproductive-aged women in northwest Ethiopia: A community-based retrospective cross-sectional study.

Int J Gynaecol Obstet 2021 Jul 29;154(1):62-71. Epub 2020 Dec 29.

Department of Environmental and Occupational Health, and Safety, Institute of Public Health, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia.

Objective: To determine the Prevalence and factors associated with pregnancy-related complications among reproductive-aged women in northwest Ethiopia.

Methods: A community-based retrospective cross-sectional study was conducted among 2367 mothers who delivered from November 2018 to April 2019. Two-stage stratified random sampling technique was employed in clustered villages from three districts out of 10. Read More

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Spatial distribution and associated factors of underweight in Ethiopia: An analysis of Ethiopian demographic and health survey, 2016.

PLoS One 2020 1;15(12):e0242744. Epub 2020 Dec 1.

Department of Epidemiology and Biostatistics, Institute of Public Health, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia.

Background: Underweight is one form of indicators of under-nutrition, which results from the poor nutrient intake and underlying health problems. Its impact is beyond an individual and extends to a country level. It has been known from the literature that underweight has a negative effect on income and development of a country. Read More

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January 2021