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Data Management And Data Quality In Perch, A Large International Case-Control Study Of Severe Childhood Pneumonia., Nora L Watson, Christine Prosperi, Amanda J Driscoll, Melissa M Higdon, Daniel E Park, Megan Sanza, Andrea N DeLuca, Juliet O Awori, Doli Goswami, Emily Hammond, Lokman Hossain, Catherine Johnson, Alice Kamau, Locadiah Kuwanda, David P Moore, Omid Neyzari, Uma Onwuchekwa, David Parker, Patranuch Sapchookul 2017 George Washington University

Data Management And Data Quality In Perch, A Large International Case-Control Study Of Severe Childhood Pneumonia., Nora L Watson, Christine Prosperi, Amanda J Driscoll, Melissa M Higdon, Daniel E Park, Megan Sanza, Andrea N Deluca, Juliet O Awori, Doli Goswami, Emily Hammond, Lokman Hossain, Catherine Johnson, Alice Kamau, Locadiah Kuwanda, David P Moore, Omid Neyzari, Uma Onwuchekwa, David Parker, Patranuch Sapchookul

Epidemiology Faculty Publications

The Pneumonia Etiology Research for Child Health (PERCH) study is the largest multicountry etiology study of pediatric pneumonia undertaken in the past 3 decades. The study enrolled 4232 hospitalized cases and 5325 controls over 2 years across 9 research sites in 7 countries in Africa and Asia. The volume and complexity of data collection in PERCH presented considerable logistical and technical challenges. The project chose an internet-based data entry system to allow real-time access to the data, enabling the project to monitor and clean incoming data and perform preliminary analyses throughout the study. To ensure high-quality data, the project developed …


Colonization Density Of The Upper Respiratory Tract As A Predictor Of Pneumonia-Haemophilus Influenzae, Moraxella Catarrhalis, Staphylococcus Aureus, And Pneumocystis Jirovecii., Daniel E Park, Henry C Baggett, Stephen R C Howie, Qiyuan Shi, Nora L Watson, W Abdullah Brooks, PERCH Study Group 2017 George Washington University

Colonization Density Of The Upper Respiratory Tract As A Predictor Of Pneumonia-Haemophilus Influenzae, Moraxella Catarrhalis, Staphylococcus Aureus, And Pneumocystis Jirovecii., Daniel E Park, Henry C Baggett, Stephen R C Howie, Qiyuan Shi, Nora L Watson, W Abdullah Brooks, Perch Study Group

Epidemiology Faculty Publications

Background.

There is limited information on the association between colonization density of upper respiratory tract colonizers and pathogen-specific pneumonia. We assessed this association for Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus, and Pneumocystis jirovecii. Methods.

In 7 low- and middle-income countries, nasopharyngeal/oropharyngeal swabs from children with severe pneumonia and age-frequency matched community controls were tested using quantitative polymerase chain reaction (PCR). Differences in median colonization density were evaluated using the Wilcoxon rank-sum test. Density cutoffs were determined using receiver operating characteristic curves. Cases with a pathogen identified from lung aspirate culture or PCR, pleural fluid culture or …


Microscopic Analysis And Quality Assessment Of Induced Sputum From Children With Pneumonia In The Perch Study., David R Murdoch, Susan C Morpeth, Laura L Hammitt, Amanda J Driscoll, Daniel E Park, +several additional authors 2017 George Washington University

Microscopic Analysis And Quality Assessment Of Induced Sputum From Children With Pneumonia In The Perch Study., David R Murdoch, Susan C Morpeth, Laura L Hammitt, Amanda J Driscoll, Daniel E Park, +Several Additional Authors

Epidemiology Faculty Publications

Background.

It is standard practice for laboratories to assess the cellular quality of expectorated sputum specimens to check that they originated from the lower respiratory tract. The presence of low numbers of squamous epithelial cells (SECs) and high numbers of polymorphonuclear (PMN) cells are regarded as indicative of a lower respiratory tract specimen. However, these quality ratings have never been evaluated for induced sputum specimens from children with suspected pneumonia. Methods.

We evaluated induced sputum Gram stain smears and cultures from hospitalized children aged 1–59 months enrolled in a large study of community-acquired pneumonia. We hypothesized that a specimen representative …


Is Higher Viral Load In The Upper Respiratory Tract Associated With Severe Pneumonia? Findings From The Perch Study., Daniel R Feikin, Wei Fu, Daniel E Park, Qiyuan Shi, Melissa M Higdon, Henry C Baggett, +several additional authors 2017 George Washington University

Is Higher Viral Load In The Upper Respiratory Tract Associated With Severe Pneumonia? Findings From The Perch Study., Daniel R Feikin, Wei Fu, Daniel E Park, Qiyuan Shi, Melissa M Higdon, Henry C Baggett, +Several Additional Authors

Epidemiology Faculty Publications

Background.

The etiologic inference of identifying a pathogen in the upper respiratory tract (URT) of children with pneumonia is unclear. To determine if viral load could provide evidence of causality of pneumonia, we compared viral load in the URT of children with World Health Organization–defined severe and very severe pneumonia and age-matched community controls.

Methods.

In the 9 developing country sites, nasopharyngeal/oropharyngeal swabs from children with and without pneumonia were tested using quantitative real-time polymerase chain reaction for 17 viruses. The association of viral load with case status was evaluated using logistic regression. Receiver operating characteristic (ROC) curves were constructed …


Association Of C-Reactive Protein With Bacterial And Respiratory Syncytial Virus-Associated Pneumonia Among Children Aged <5 Years In The Perch Study., Melissa M Higdon, Tham Le, Katherine L O'Brien, David R Murdoch, Christine Prosperi, Henry C Baggett, Daniel E Park, +several additional authors 2017 George Washington University

Association Of C-Reactive Protein With Bacterial And Respiratory Syncytial Virus-Associated Pneumonia Among Children Aged <5 Years In The Perch Study., Melissa M Higdon, Tham Le, Katherine L O'Brien, David R Murdoch, Christine Prosperi, Henry C Baggett, Daniel E Park, +Several Additional Authors

Epidemiology Faculty Publications

Background.

Lack of a gold standard for identifying bacterial and viral etiologies of pneumonia has limited evaluation of C-reactive protein (CRP) for identifying bacterial pneumonia. We evaluated the sensitivity and specificity of CRP for identifying bacterial vs respiratory syncytial virus (RSV) pneumonia in the Pneumonia Etiology Research for Child Health (PERCH) multicenter case-control study. Methods.

We measured serum CRP levels in cases with World Health Organization–defined severe or very severe pneumonia and a subset of community controls. We evaluated the sensitivity and specificity of elevated CRP for “confirmed” bacterial pneumonia (positive blood culture or positive lung aspirate or pleural fluid …


Standardization Of Clinical Assessment And Sample Collection Across All Perch Study Sites., Jane Crawley, Christine Prosperi, Henry C Baggett, W Abdullah Brooks, Maria Deloria Knoll, Daniel E Park, +several additional authors 2017 George Washington University

Standardization Of Clinical Assessment And Sample Collection Across All Perch Study Sites., Jane Crawley, Christine Prosperi, Henry C Baggett, W Abdullah Brooks, Maria Deloria Knoll, Daniel E Park, +Several Additional Authors

Epidemiology Faculty Publications

Background.: Variable adherence to standardized case definitions, clinical procedures, specimen collection techniques, and laboratory methods has complicated the interpretation of previous multicenter pneumonia etiology studies. To circumvent these problems, a program of clinical standardization was embedded in the Pneumonia Etiology Research for Child Health (PERCH) study.

Methods.: Between March 2011 and August 2013, standardized training on the PERCH case definition, clinical procedures, and collection of laboratory specimens was delivered to 331 clinical staff at 9 study sites in 7 countries (The Gambia, Kenya, Mali, South Africa, Zambia, Thailand, and Bangladesh), through 32 on-site courses and a training website. Staff competency …


The Diagnostic Utility Of Induced Sputum Microscopy And Culture In Childhood Pneumonia., David R Murdoch, Susan C Morpeth, Laura L Hammitt, Amanda J Driscoll, Nora L Watson, Daniel E Park, +several additional authors 2017 George Washington University

The Diagnostic Utility Of Induced Sputum Microscopy And Culture In Childhood Pneumonia., David R Murdoch, Susan C Morpeth, Laura L Hammitt, Amanda J Driscoll, Nora L Watson, Daniel E Park, +Several Additional Authors

Epidemiology Faculty Publications

Background.

Sputum microscopy and culture are commonly used for diagnosing the cause of pneumonia in adults but are rarely performed in children due to difficulties in obtaining specimens. Induced sputum is occasionally used to investigate lower respiratory infections in children but has not been widely used in pneumonia etiology studies. Methods.

We evaluated the diagnostic utility of induced sputum microscopy and culture in patients enrolled in the Pneumonia Etiology Research for Child Health (PERCH) study, a large study of community-acquired pneumonia in children aged 1–59 months. Comparisons were made between induced sputum samples from hospitalized children with radiographically confirmed pneumonia …


Treatment Pathway Of Bone Sarcoma In Children, Adolescents, And Young Adults, Damon R. Reed, Masanori Hayashi, Lars M. Wagner, Odion Binitie, Diana A. Steppan, Andrew S. Brohl, Eric T. Shinohara, Julia A. Bridge, David M. Loeb, Scott C. Borinstein, Michael S. Isakoff 2017 H. Lee Moffitt Cancer Center and Research Institute

Treatment Pathway Of Bone Sarcoma In Children, Adolescents, And Young Adults, Damon R. Reed, Masanori Hayashi, Lars M. Wagner, Odion Binitie, Diana A. Steppan, Andrew S. Brohl, Eric T. Shinohara, Julia A. Bridge, David M. Loeb, Scott C. Borinstein, Michael S. Isakoff

Pediatrics Faculty Publications

When pediatric, adolescent, and young adult patients present with a bone sarcoma, treatment decisions, especially after relapse, are complex and require a multidisciplinary approach. This review presents scenarios commonly encountered in the therapy of bone sarcomas with the goal of objectively presenting a consensus, multidisciplinary management approach. Little variation was found in the authors' group with respect to local control or systemic therapy. Clinical trials were universally prioritized in all settings. Decisions regarding relapse therapies in the absence of a clinical trial had very minor variations initially, but a consensus was reached after a literature review and discussion. This review …


Identifying Risk Factors For Interstate Crashes Using Spatial Statistics, Kaitlin Gibson, Matthew Heaton 2017 Brigham Young University

Identifying Risk Factors For Interstate Crashes Using Spatial Statistics, Kaitlin Gibson, Matthew Heaton

Journal of Undergraduate Research

The goal of systemic highway safety improvement is to identify road characteristics, called risk factors, associated with a higher prevalence of crashes, so that the roads can be modified to avoid these characteristics. However, the statistical analyses these improvement projects are based on generally use methods which are not appropriate for the data. Our project implements novel spatial statistical methodology which is appropriate and state-of-the-art to identify these risk factors.


An Algorithm For Multiple Regression Variable Selection For Biochemical Oxygen Demand, Zach White, Dr. William Christensen 2017 Brigham Young University

An Algorithm For Multiple Regression Variable Selection For Biochemical Oxygen Demand, Zach White, Dr. William Christensen

Journal of Undergraduate Research

Biochemical Oxygen Demand (BOD) is used to measure of the amount of oxygen required by aerobic bacteria and other microorganisms to stabilize decomposable organic matter. It is run as a laboratory based biodegradation test and relies upon the presence of a thriving microbial community that may be naturally present in the sample or artificially introduced by addition of a seed, commonly a known volume of sewage effluent of known BOD. A standard BOD test is run in the dark at a temperature of 20 degrees Celsius for 5 days. This is defined as a five-day BOD (BOD5), which is the …


Real-Time Classification Of Biomedical Signals, Parkinson’S Analytical Model, Abolfazl Saghafi 2017 University of South Florida

Real-Time Classification Of Biomedical Signals, Parkinson’S Analytical Model, Abolfazl Saghafi

USF Tampa Graduate Theses and Dissertations

The reach of technological innovation continues to grow, changing all industries as it evolves. In healthcare, technology is increasingly playing a role in almost all processes, from patient registration to data monitoring, from lab tests to self-care tools. The increase in the amount and diversity of generated clinical data requires development of new technologies and procedures capable of integrating and analyzing the BIG generated information as well as providing support in their interpretation.

To that extent, this dissertation focuses on the analysis and processing of biomedical signals, specifically brain and heart signals, using advanced machine learning techniques. That is, the …


Optimal, Two Stage, Adaptive Enrichment Designs For Randomized Trials Using Sparse Linear Programming, Michael Rosenblum, Xingyuan Fang, Han Liu 2017 Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health

Optimal, Two Stage, Adaptive Enrichment Designs For Randomized Trials Using Sparse Linear Programming, Michael Rosenblum, Xingyuan Fang, Han Liu

Johns Hopkins University, Dept. of Biostatistics Working Papers

Adaptive enrichment designs involve preplanned rules for modifying enrollment criteria based on accruing data in a randomized trial. We focus on designs where the overall population is partitioned into two predefined subpopulations, e.g., based on a biomarker or risk score measured at baseline. The goal is to learn which populations benefit from an experimental treatment. Two critical components of adaptive enrichment designs are the decision rule for modifying enrollment, and the multiple testing procedure. We provide a general method for simultaneously optimizing these components for two stage, adaptive enrichment designs. We minimize the expected sample size under constraints on power …


How To Estimate Statistical Characteristics Based On A Sample: Nonparametric Maximum Likelihood Approach Leads To Sample Mean, Sample Variance, Etc., Vladik Kreinovich, Thongchai Dumrongpokaphan 2017 The University of Texas at El Paso

How To Estimate Statistical Characteristics Based On A Sample: Nonparametric Maximum Likelihood Approach Leads To Sample Mean, Sample Variance, Etc., Vladik Kreinovich, Thongchai Dumrongpokaphan

Departmental Technical Reports (CS)

In many practical situations, we need to estimate different statistical characteristics based on a sample. In some cases, we know that the corresponding probability distribution belongs to a known finite-parametric family of distributions. In such cases, a reasonable idea is to use the Maximum Likelihood method to estimate the corresponding parameters, and then to compute the value of the desired statistical characteristic for the distribution with these parameters.

In some practical situations, we do not know any family containing the unknown distribution. We show that in such nonparametric cases, the Maximum Likelihood approach leads to the use of sample mean, …


Non-Normality And Heteroscedasticity In Regression And Anova, Harry Wu 2017 California Polytechnic State University, San Luis Obispo

Non-Normality And Heteroscedasticity In Regression And Anova, Harry Wu

Statistics

No abstract provided.


Comparing Baseball Players Using Expected Runs In Shiny, Spencer Rodrigues 2017 California Polytechnic State University, San Luis Obispo

Comparing Baseball Players Using Expected Runs In Shiny, Spencer Rodrigues

Statistics

No abstract provided.


Analyzing Baseball Data With R, Claudia Sison 2017 California Polytechnic State University, San Luis Obispo

Analyzing Baseball Data With R, Claudia Sison

Statistics

No abstract provided.


Impact Of Serum Sp-A And Sp-D Levels On Comparison And Prognosis Of Idiopathic Pulmonary Fibrosis: A Systematic Review And Meta-Analysis., Kai Wang, Qing Ju, Jing Cao, Wenze Tang, Jian Zhang 2017 George Washington University

Impact Of Serum Sp-A And Sp-D Levels On Comparison And Prognosis Of Idiopathic Pulmonary Fibrosis: A Systematic Review And Meta-Analysis., Kai Wang, Qing Ju, Jing Cao, Wenze Tang, Jian Zhang

Epidemiology Faculty Publications

Background and objective:

Idiopathic pulmonary fibrosis (IPF) has a poor prognosis in general; however, it is heterogeneous to detect relative biomarkers for predicting the disease progression. Serum biomarkers can be conveniently collected to detect and help to differentially diagnose IPF and predict IPF prognosis. This meta-analysis aimed to evaluate the use of serum surfactant proteins A and D (SP-A and SP-D) for differential diagnosis and prognosis of IPF.

Methods:

Relevant articles were searched in PubMed, Embase, and Chinese National Knowledge Infrastructuredatabases and reviewed by 2 independent readers. Standard mean difference (SMD) and 95% confidence interval (CI) were …


Gridiron-Gurus Final Report: Fantasy Football Performance Prediction, Kyle Tanemura, Michael Li, Erica Dorn, Ryan McKinney 2017 California Polytechnic State University, San Luis Obispo

Gridiron-Gurus Final Report: Fantasy Football Performance Prediction, Kyle Tanemura, Michael Li, Erica Dorn, Ryan Mckinney

Computer Science and Software Engineering

Gridiron Gurus is a desktop application that allows for the creation of custom AI profiles to help advise and compete against in a Fantasy Football setting. Our AI are capable of performing statistical prediction of players on both a season long and week to week basis giving them the ability to both draft and manage a fantasy football team throughout a season.


Understanding Angiography-Based Aneurysm Flow Fields Through Comparison With Computational Fluid Dynamics, Juan R. Cebral, F. Mut, Bong Jae Chung, L. Spelle, J. Moret, F. Van Nijnatten, D. Ruijters 2017 George Mason University

Understanding Angiography-Based Aneurysm Flow Fields Through Comparison With Computational Fluid Dynamics, Juan R. Cebral, F. Mut, Bong Jae Chung, L. Spelle, J. Moret, F. Van Nijnatten, D. Ruijters

Department of Applied Mathematics and Statistics Faculty Scholarship and Creative Works

BACKGROUND AND PURPOSE: Hemodynamics is thought to be an important factor for aneurysm progression and rupture. Our aim was to evaluate whether flow fields reconstructed from dynamic angiography data can be used to realistically represent the main flow structures in intracranial aneurysms. MATERIALS AND METHODS: DSA-based flow reconstructions, obtained during interventional treatment, were compared qualitatively with flow fields obtained from patient-specific computational fluid dynamics models and quantitatively with projections of the computational fluid dynamics fields (by computing a directional similarity of the vector fields) in 15 cerebral aneurysms. RESULTS: The average similarity between the DSA and the projected computational fluid …


An M/G/1 Retrial Queue With Single Working Vacation, S. P. Bala Murugan, K. Santhi 2017 Annamalai University

An M/G/1 Retrial Queue With Single Working Vacation, S. P. Bala Murugan, K. Santhi

Applications and Applied Mathematics: An International Journal (AAM)

We consider an M=G=1 retrial queue with general retrial times and single working vacation. During the working vacation period, customers can be served at a lower rate. Both service times in a vacation period and in a service period are generally distributed random variables. Using supplementary variable method we obtain the probability generating function for the number of customers and the average number of customers in the orbit. Furthermore, we carry out the waiting time distribution and some special cases of interest are discussed. Finally, some numerical results are presented.


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