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Quantitative Electroencephalography For Detecting Concussions, Sara Krehbiel, Kathy Hoke, Joanna Wares 2018 University of Richmond

Quantitative Electroencephalography For Detecting Concussions, Sara Krehbiel, Kathy Hoke, Joanna Wares

Biology and Medicine Through Mathematics Conference

No abstract provided.


The Ethics In Synthetics: Statistics In The Service Of Ethics And Law In Health-Related Research In Big Data From Multiple Sources, Sharon Bassan Ph.D., Ofer Harel Ph.D. 2018 Princeton University

The Ethics In Synthetics: Statistics In The Service Of Ethics And Law In Health-Related Research In Big Data From Multiple Sources, Sharon Bassan Ph.D., Ofer Harel Ph.D.

Journal of Law and Health

An ethical advancement of scientific knowledge demands a delicate equilibrium between benefits and harms, in particular in health-related research. When applying and advancing scientific knowledge or technologies, Article 4 of UNESCO’s Universal Declaration on Bioethics and Human Rights, ethically justifiable research requires maximizing direct and indirect benefits and minimizing possible harms. The National Institution of Health [NIH] Data Sharing Policy and Implementation Guidance similarly states that data necessary for drawing valid conclusions and advancing medical research should be made as widely and freely available as possible (in order to share the benefits) while safeguarding the privacy of participants from ...


Oxidative Stress And Cardiovascular Risk In Type 1 Diabetes Mellitus: Insights From The Dcct/Edic Study, W. Wilson Tang, P. McGee, John M. Lachin, D. Li, B. Hoogwerf, S. Hazen, +several additional authors 2018 George Washington University

Oxidative Stress And Cardiovascular Risk In Type 1 Diabetes Mellitus: Insights From The Dcct/Edic Study, W. Wilson Tang, P. Mcgee, John M. Lachin, D. Li, B. Hoogwerf, S. Hazen, +Several Additional Authors

Epidemiology and Biostatistics Faculty Publications

Background--Hyperglycemia leading to increased oxidative stress is implicated in the increased risk for the development of macrovascular and microvascular complications in patients with type 1 diabetes mellitus. Methods and Results--A random subcohort of 349 participants was selected from the DCCT/EDIC (Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications) cohort. This included 320 controls and 29 cardiovascular disease cases that were augmented with 98 additional known cases to yield a case cohort of 447 participants (320 controls, 127 cases). Biosamples from DCCT baseline, year 1, and closeout of DCCT, and 1 to 2 years post-DCCT (EDIC years ...


Aggressive Diuresis And Severity-Adjusted Length Of Hospital Stay In Acute Congestive Heart Failure Patients., Muhammad U. Butt M.D. 2018 Selected Works

Aggressive Diuresis And Severity-Adjusted Length Of Hospital Stay In Acute Congestive Heart Failure Patients., Muhammad U. Butt M.D.

Muhammad Umer Butt M.D., MSCRD

To see if aggressive diuresis in 1st 24 hours is associated with a comparable number of total days in the hospital as compared to non-aggressive diuresis.  In this retrospective cohort study, we compared the length of hospital stay of consecutive patients admitted in one year based on their diuresis during the first twenty-four hours of hospitalization: aggressive diuresis (group 1) i.e. >2400mL versus non-aggressive diuresis (group 2) i.e. ≤ 2400mL urine output. Patients were excluded if in cardiogenic shock, had creatinine level above 3 mg/dL on admission, or on dialysis. A total of 194 patients were enrolled (29 ...


Analysis Challenges For High Dimensional Data, Bangxin Zhao 2018 The University of Western Ontario

Analysis Challenges For High Dimensional Data, Bangxin Zhao

Electronic Thesis and Dissertation Repository

In this thesis, we propose new methodologies targeting the areas of high-dimensional variable screening, influence measure and post-selection inference. We propose a new estimator for the correlation between the response and high-dimensional predictor variables, and based on the estimator we develop a new screening technique termed Dynamic Tilted Current Correlation Screening (DTCCS) for high dimensional variables screening. DTCCS is capable of picking up the relevant predictor variables within a finite number of steps. The DTCCS method takes the popular used sure independent screening (SIS) method and the high-dimensional ordinary least squares projection (HOLP) approach as its special cases.

Two methods ...


Cross-Sectional Hiv Incidence Estimation Accounting For Heterogeneity Across Communities, Yuejia Xu, Oliver B. Laeyendecker, Rui Wang 2018 University of Cambridge

Cross-Sectional Hiv Incidence Estimation Accounting For Heterogeneity Across Communities, Yuejia Xu, Oliver B. Laeyendecker, Rui Wang

Harvard University Biostatistics Working Paper Series

No abstract provided.


Developing Statistical Methods For Data From Platforms Measuring Gene Expression, Gaoxiang Jia 2018 Southern Methodist University

Developing Statistical Methods For Data From Platforms Measuring Gene Expression, Gaoxiang Jia

Statistical Science Theses and Dissertations

This research contains two topics: (1) PBNPA: a permutation-based non-parametric analysis of CRISPR screen data; (2) RCRnorm: an integrated system of random-coefficient hierarchical regression models for normalizing NanoString nCounter data from FFPE samples.

Clustered regularly-interspaced short palindromic repeats (CRISPR) screens are usually implemented in cultured cells to identify genes with critical functions. Although several methods have been developed or adapted to analyze CRISPR screening data, no single spe- cific algorithm has gained popularity. Thus, rigorous procedures are needed to overcome the shortcomings of existing algorithms. We developed a Permutation-Based Non-Parametric Analysis (PBNPA) algorithm, which computes p-values at the gene level ...


Physical Activity Across The Lifespan And Liver Cancer Incidence In The Nih-Aarp Diet And Health Study Cohort., Hannah Arem, Erikka Loftfield, Pedro F Saint-Maurice, Neal D Freedman, Charles E Matthews 2018 George Washington University

Physical Activity Across The Lifespan And Liver Cancer Incidence In The Nih-Aarp Diet And Health Study Cohort., Hannah Arem, Erikka Loftfield, Pedro F Saint-Maurice, Neal D Freedman, Charles E Matthews

Epidemiology and Biostatistics Faculty Publications

While liver cancer rates in the United States are increasing, 5-year survival is only 17.6%, underscoring the importance of prevention. Physical activity has been associated with lower risk of developing liver cancer, but most studies assess physical activity only at a single point in time, often in midlife. We utilized physical activity data from 296,661 men and women in the NIH-AARP Diet and Health Study cohort to test whether physical activity patterns over the life course could elucidate the importance of timing of physical activity on liver cancer risk. We used group modeling of longitudinal data to create ...


Robust Estimation Of The Average Treatment Effect In Alzheimer's Disease Clinical Trials, Michael Rosenblum, Aidan McDermont, Elizabeth Colantuoni 2018 Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health

Robust Estimation Of The Average Treatment Effect In Alzheimer's Disease Clinical Trials, Michael Rosenblum, Aidan Mcdermont, Elizabeth Colantuoni

Johns Hopkins University, Dept. of Biostatistics Working Papers

The primary analysis of Alzheimer's disease clinical trials often involves a mixed-model repeated measure (MMRM) approach. We consider another estimator of the average treatment effect, called targeted minimum loss based estimation (TMLE). This estimator is more robust to violations of assumptions about missing data than MMRM.

We compare TMLE versus MMRM by analyzing data from a completed Alzheimer's disease trial data set and by simulation studies. The simulations involved different missing data distributions, where loss to followup at a given visit could depend on baseline variables, treatment assignment, and the outcome measured at previous visits. The TMLE generally ...


Therapy Dogs On Campus: An Exploration Of How Dog Therapy Services Affect Undergraduate Students’ Stress Levels, Tanna Lauriente, Drayden A.D. Kopp 2018 Thompson River's University

Therapy Dogs On Campus: An Exploration Of How Dog Therapy Services Affect Undergraduate Students’ Stress Levels, Tanna Lauriente, Drayden A.D. Kopp

Proceedings of the Annual Thompson Rivers University Undergraduate Research and Innovation Conference

University can be stressful for many undergraduates. Fortunately, there are various stress reduction strategies, including weekly dog therapy sessions, offered at Thompson Rivers University. This study investigated the effects of dog therapy on students via a self-reported stress survey. Students in a control group (n= 98), who did not visit the therapy dogs, and a test group (n= 108), who did, provided data on their stress level and various other factors. Students in the test group reported their stress levels before and after participating in a dog therapy session by circling a number on our stress scale, determining their stress ...


Perceived Access And Barriers To Care Among Illicit Drug Users And Hazardous Drinkers: Findings From The Seek, Test, Treat, And Retain Data Harmonization Initiative (Sttr)., Mika Matsuzaki, Quan M Vu, Marya Gwadz, Joseph A C Delaney, Irene Kuo, Maria Esther Perez Trejo, William E Cunningham, Chinazo O Cunningham, Katerina Christopoulos 2018 George Washington University

Perceived Access And Barriers To Care Among Illicit Drug Users And Hazardous Drinkers: Findings From The Seek, Test, Treat, And Retain Data Harmonization Initiative (Sttr)., Mika Matsuzaki, Quan M Vu, Marya Gwadz, Joseph A C Delaney, Irene Kuo, Maria Esther Perez Trejo, William E Cunningham, Chinazo O Cunningham, Katerina Christopoulos

Epidemiology and Biostatistics Faculty Publications

BACKGROUND: Illicit drug use (DU) and hazardous drinking (HD) among marginalized populations may be associated with greater barriers to care.

METHODS: We used baseline data on the participants of the Seek, Test, Treat, and Retain data harmonization initiative. DU includes use of any illicit drugs within the past 6 months. HD was defined as scores ≥8 for men and ≥ 7 for women on Alcohol Use Disorders Identification Test within the past 12 months. Social support scores were assigned by summing scores from individual questions related to social support. Two outcomes for multivariable regression models and mediation analysis were perceived access ...


Incorporating Historical Models With Adaptive Bayesian Updates, Philip S. Boonstra, Ryan P. Barbaro 2018 The University Of Michigan

Incorporating Historical Models With Adaptive Bayesian Updates, Philip S. Boonstra, Ryan P. Barbaro

The University of Michigan Department of Biostatistics Working Paper Series

This paper considers Bayesian approaches for incorporating information from a historical model into a current analysis when the historical model includes only a subset of covariates currently of interest. The statistical challenge is two-fold. First, the parameters in the nested historical model are not generally equal to their counterparts in the larger current model, neither in value nor interpretation. Second, because the historical information will not be equally informative for all parameters in the current analysis, additional regularization may be required beyond that provided by the historical information. We propose several novel extensions of the so-called power prior that adaptively ...


A Spline-Assisted Semiparametric Approach To Nonparametric Measurement Error Models, Fei Jiang, Yanyuan Ma 2018 The University of Hong Kong

A Spline-Assisted Semiparametric Approach To Nonparametric Measurement Error Models, Fei Jiang, Yanyuan Ma

COBRA Preprint Series

Nonparametric estimation of the probability density function of a random variable measured with error is considered to be a difficult problem, in the sense that depending on the measurement error prop- erty, the estimation rate can be as slow as the logarithm of the sample size. Likewise, nonparametric estimation of the regression function with errors in the covariate suffers the same possibly slow rate. The traditional methods for both problems are based on deconvolution, where the slow convergence rate is caused by the quick convergence to zero of the Fourier transform of the measurement error density, which, unfortunately, appears in ...


Integrated Bioinformatics, Environmental Epidemiologic And Genomic Approaches To Identify Environmental And Molecular Links Between Endometriosis And Breast Cancer, Deodutta Roy, Marisa L. Morgan, Changwon Yoo, Alok Deoraj, Sandhya Roy, Vijay Kumar Yadav, Mohannad Garoub, Hamza Assaggaf, Mayur Doke 2018 Department of Environmental and Occupational Health, Florida International University

Integrated Bioinformatics, Environmental Epidemiologic And Genomic Approaches To Identify Environmental And Molecular Links Between Endometriosis And Breast Cancer, Deodutta Roy, Marisa L. Morgan, Changwon Yoo, Alok Deoraj, Sandhya Roy, Vijay Kumar Yadav, Mohannad Garoub, Hamza Assaggaf, Mayur Doke

Alok Deoraj

We present a combined environmental epidemiologic, genomic, and bioinformatics approach to identify: exposure of environmental chemicals with estrogenic activity; epidemiologic association between endocrine disrupting chemical (EDC) and health effects, such as, breast cancer or endometriosis; and gene-EDC interactions and disease associations. Human exposure measurement and modeling confirmed estrogenic activity of three selected class of environmental chemicals, polychlorinated biphenyls (PCBs), bisphenols (BPs), and phthalates. Meta-analysis showed that PCBs exposure, not Bisphenol A (BPA) and phthalates, increased the summary odds ratio for breast cancer and endometriosis. Bioinformatics analysis of gene-EDC interactions and disease associations identified several hundred genes that were altered by ...


The Association Of Long-Term Exposure To Particulate Matter Air Pollution With Brain Mri Findings: The Aric Study., Melinda C Power, Archana P Lamichhane, Duanping Liao, Xiaohui Xu, Clifford R Jack, Rebecca F Gottesman, Thomas Mosley, James D Stewart, Jeff D Yanosky, Eric A Whitsel 2018 George Washington University

The Association Of Long-Term Exposure To Particulate Matter Air Pollution With Brain Mri Findings: The Aric Study., Melinda C Power, Archana P Lamichhane, Duanping Liao, Xiaohui Xu, Clifford R Jack, Rebecca F Gottesman, Thomas Mosley, James D Stewart, Jeff D Yanosky, Eric A Whitsel

Epidemiology and Biostatistics Faculty Publications

BACKGROUND: Increasing evidence links higher particulate matter (PM) air pollution exposure to late-life cognitive impairment. However, few studies have considered associations between direct estimates of long-term past exposures and brain MRI findings indicative of neurodegeneration or cerebrovascular disease.

OBJECTIVE: Our objective was to quantify the association between brain MRI findings and PM exposures approximately 5 to 20 y prior to MRI in the Atherosclerosis Risk in Communities (ARIC) study.

METHODS: ARIC is based in four U.S. sites: Washington County, Maryland; Minneapolis suburbs, Minnesota; Forsyth County, North Carolina; and Jackson, Mississippi. A subset of ARIC participants underwent 3T brain MRI ...


A Ten-Year Comparison Of Women Authorship In U.S. Dermatology Literature, 1999 Vs. 2009, Shali Zhang, Ha-Young Kim, Rachel E.S. Hill, Emir Veledar, Suephy C. Chen 2018 Emory University

A Ten-Year Comparison Of Women Authorship In U.S. Dermatology Literature, 1999 Vs. 2009, Shali Zhang, Ha-Young Kim, Rachel E.S. Hill, Emir Veledar, Suephy C. Chen

Emir Veledar

Women are entering medicine at increasing rates, particularly in dermatology. In this study, we compared women’s influence and status in academic dermatology with that of men by examining authorship roles in peer-reviewed dermatology literature.Weexamined the literature in2009 and compared that to10 years prior (1999).Atotal of 1399 articles were reviewed, 594 of whichmet study criteria andwere included in statistical analysis. There was amarked increase in senior female authorship over a decade (22% vs. 38%, p b 0.001). Female first authorship increased as well (41% vs. 51%, p b 0.001). In contrast, changes in male senior and ...


Optimized Adaptive Enrichment Designs For Multi-Arm Trials: Learning Which Subpopulations Benefit From Different Treatments, Jon Arni Steingrimsson, Joshua Betz, Tiachen Qian, Michael Rosenblum 2018 Department of Biostatistics, Brown School of Public Health

Optimized Adaptive Enrichment Designs For Multi-Arm Trials: Learning Which Subpopulations Benefit From Different Treatments, Jon Arni Steingrimsson, Joshua Betz, Tiachen Qian, Michael Rosenblum

Johns Hopkins University, Dept. of Biostatistics Working Papers

We consider the problem of designing a randomized trial for comparing two treatments versus a common control in two disjoint subpopulations. The subpopulations could be defined in terms of a biomarker or disease severity measured at baseline. The goal is to determine which treatments benefit which subpopulations. We develop a new class of adaptive enrichment designs tailored to solving this problem. Adaptive enrichment designs involve a preplanned rule for modifying enrollment based on accruing data in an ongoing trial. The proposed designs have preplanned rules for stopping accrual of treatment by subpopulation combinations, either for efficacy or futility. The motivation ...


Phase Ii Adaptive Enrichment Design To Determine The Population To Enroll In Phase Iii Trials, By Selecting Thresholds For Baseline Disease Severity, Yu Du, Gary L. Rosner, Michael Rosenblum 2018 Johns Hopkins Bloomberg School of Public Health, Department of Biostatistics

Phase Ii Adaptive Enrichment Design To Determine The Population To Enroll In Phase Iii Trials, By Selecting Thresholds For Baseline Disease Severity, Yu Du, Gary L. Rosner, Michael Rosenblum

Johns Hopkins University, Dept. of Biostatistics Working Papers

We propose and evaluate a two-stage, phase 2, adaptive clinical trial design. Its goal is to determine whether future phase 3 (confirmatory) trials should be conducted, and if so, which population should be enrolled. The population selected for phase 3 enrollment is defined in terms of a disease severity score measured at baseline. We optimize the phase 2 trial design and analysis in a decision theory framework. Our utility function represents a combination of the cost of conducting phase 3 trials and, if the phase 3 trials are successful, the improved health of the future population minus the cost of ...


Big Data And Parkinson’S Disease: Exploration, Analyses, And Data Challenges, Mahalakshmi SenthilarumugamVeilukandammal, Sree Nilakanta, Baskar Ganapathysubramanian, Vellareddy Anantharam, Anumantha Kanthasamy, Auriel A. Willette 2018 Iowa State University

Big Data And Parkinson’S Disease: Exploration, Analyses, And Data Challenges, Mahalakshmi Senthilarumugamveilukandammal, Sree Nilakanta, Baskar Ganapathysubramanian, Vellareddy Anantharam, Anumantha Kanthasamy, Auriel A. Willette

Mechanical Engineering Conference Presentations, Papers, and Proceedings

In healthcare, a tremendous amount of clinical and laboratory tests, imaging, prescription and medication data are being collected. Big data analytics on these data aim at early detection of disease which will help in developing preventive measures and in improving patient care. Parkinson disease is the second-most common neurodegenerative disorder in the United States. To find a cure for Parkinson's disease biological, clinical and behavioral data of different cohorts are collected, managed and propagated through Parkinson’s Progression Markers Initiative (PPMI). Applying big data technology to this data will lead to the identification of the potential biomarkers of Parkinson ...


Improved Methods And Selecting Classification Types For Time-Dependent Covariates In The Marginal Analysis Of Longitudinal Data, I-Chen Chen 2018 University of Kentucky

Improved Methods And Selecting Classification Types For Time-Dependent Covariates In The Marginal Analysis Of Longitudinal Data, I-Chen Chen

Theses and Dissertations--Epidemiology and Biostatistics

Generalized estimating equations (GEE) are popularly utilized for the marginal analysis of longitudinal data. In order to obtain consistent regression parameter estimates, these estimating equations must be unbiased. However, when certain types of time-dependent covariates are presented, these equations can be biased unless an independence working correlation structure is employed. Moreover, in this case regression parameter estimation can be very inefficient because not all valid moment conditions are incorporated within the corresponding estimating equations. Therefore, approaches using the generalized method of moments or quadratic inference functions have been proposed for utilizing all valid moment conditions. However, we have found that ...


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