Public Health Commons^™

A Maximum Pseudo-Likelihood Approach For Estimating Species Trees Under The Coalescent Model, Liang Liu, Lili Yu, Scott V. Edwards

Biostatistics: Faculty Publications

Background

Several phylogenetic approaches have been developed to estimate species trees from collections of gene trees. However, maximum likelihood approaches for estimating species trees under the coalescent model are limited. Although the likelihood of a species tree under the multispecies coalescent model has already been derived by Rannala and Yang, it can be shown that the maximum likelihood estimate (MLE) of the species tree (topology, branch lengths, and population sizes) from gene trees under this formula does not exist. In this paper, we develop a pseudo-likelihood function of the species tree to obtain maximum pseudo-likelihood estimates (MPE) of species trees, …

The Pathways To Mental Health Care Of First-Episode Psychosis Patients: A Systematic Review., Kelly K. Anderson, Rebecca Fuhrer, Ashok K. Malla

Epidemiology and Biostatistics Publications

BACKGROUND: Although there is agreement on the association between delay in treatment of psychosis and outcome, less is known regarding the pathways to care of patients suffering from a first psychotic episode. Pathways are complex, involve a diverse range of contacts, and are likely to influence delay in treatment. We conducted a systematic review on the nature and determinants of the pathway to care of patients experiencing a first psychotic episode.

METHOD: We searched four databases (Medline, HealthStar, EMBASE, PsycINFO) to identify articles published between 1985 and 2009. We manually searched reference lists and relevant journals and used forward citation …

Importance Of Wildlife Disease Surveillance, Jerrold L. Belant, Amanda R. Deese

Human–Wildlife Interactions

A commentary on the importance of wildlife disease surveillance.

Landmark Prediction Of Survival, Layla Parast, Tianxi Cai

Harvard University Biostatistics Working Paper Series

No abstract provided.

Hiv And Hepatocellular And Esophageal Carcinomas Related To Consumption Of Mycotoxin-Prone Foods In Sub-Saharan Africa, Jonathan H. Williams, Jessica A. Grubbs, Jerry W. Davis, Jia-Sheng Wang, Pauline E. Jolly, Nii-Ayi Ankrah, William O. Ellis, Evans Afriyie-Gyawu, Natalie M. Johnson, Abraham G. Robinson, Timothy D. Phillips

Environmental Health Sciences: Faculty Publications

Background: Promotion of the HIV epidemic by aflatoxin is postulated but not yet established. Sub-Saharan populations commonly consume food contaminated by mycotoxins, particularly aflatoxins (predominantly found in peanut, maize, rice, and cassava) and fumonisins, which occur primarily in maize. Aflatoxin promotes hepatocellular cancer, and fumonisin may promote esophageal cancer.

Objectives: This analysis was undertaken to test the hypotheses that consumption of mycotoxin-prone staple foods is 1) related to the incidence of HIV infection in Africa and 2) related to “signature” cancer rates confirming exposure to aflatoxins and fumonisins.

Design: World Health Organization data for causes of death and the Food …

Improving Statistical Analysis Of Prospective Clinical Trials In Stem Cell Transplantation. An Inventory Of New Approaches In Survival Analysis, Aurelien Latouche

COBRA Preprint Series

The CLINT project is an European Union funded project, run as a specific support action, under the sixth framework programme. It is a 2 year project aimed at supporting the European Group for Blood and Marrow Transplantation (EBMT) to develop its infrastructure for the conduct of trans-European clinical trials in accordance with the EU Clinical Trials Directive, and to facilitate International prospective clinical trials in stem cell transplantation. The initial task is to create an inventory of the existing biostatistical literature on new approaches to survival analyses that are not currently widely utilised. The estimation of survival endpoints is introduced, …

Chhs June Enewsletter, Dr. John Bonaguro, Dean, Vashon S. Wells, Editor, Wku College Of Health & Human Services

College of Health & Human Services Publications

No abstract provided.

Emergency Department Staff Adherence To Bad News Delivery Recommendations, Kristen R. Myers

Loma Linda University Electronic Theses, Dissertations & Projects

Emergency department (ED) staff is responsible for giving bad news regarding death, diagnoses, and other traumatic losses to patients and loved ones. Individuals receiving traumatic and sudden bad news are at increased risk of serious psychological and physiological consequences of disrupted grief. Despite published recommended practices for providers to help prevent maladaptive grief responses, little research is available on actual bad news delivery practices and factors promoting or hindering adherence to recommendations, and no study specifically explored the ED context.

The study used a qualitative design to explore bad news delivery practices, awareness of recommendations, factors perceived to hinder or …

Nonparametric Regression With Missing Outcomes Using Weighted Kernel Estimating Equations, Lu Wang, Andrea Rotnitzky, Xihong Lin

Harvard University Biostatistics Working Paper Series

No abstract provided.

A Pda Intervention To Sustain Smoking Cessation In Clients With Socioeconomic Vulnerability, Lynne Buchanan, Deepak Khazanchi

Information Systems and Quantitative Analysis Faculty Publications

This article describes a pilot study to explore use of a personal digital assistant (PDA) to sustain smoking cessation after discharge in clients with socioeconomic vulnerability. The major aim is to describe technology acceptance (perceived ease of use, usefulness, and attitude), portability, technical difficulty, satisfaction, and use time. The sample includes 31 medical surgical clients with average age of 47.35 (±13.3), average household income of $13,629 (±8,204), average number in the household of 2.67 (±2.22), and average education of 11th grade. The results demonstrate mean use time of 9.28 (±3.23) hr, or about 1 hr over 8 weeks. Technology acceptance …

Culturally-Adapted And Audio-Technology Assisted Hiv/Aids Awareness And Education Program In Rural Nigeria: A Cohort Study, Ighovwerha Ofotokun, Jose Nilo G. Binongo, Eli S. Rosenberg, Michael Kane, Rick Ifland, Jeffrey L. Lennox, Kirk A. Easley

Faculty Articles

Background: HIV-awareness programs tailored toward the needs of rural communities are needed. We sought to quantify change in HIV knowledge in three rural Nigerian villages following an integrated culturally adapted and technology assisted educational intervention.

Methods: A prospective 14-week cohort study was designed to compare short-term changes in HIV knowledge between seminar-based education program and a novel program, which capitalized on the rural culture of small-group oral learning and was delivered by portable digital-audio technology.

Results: Participants were mostly Moslem (99%), male (53.5%), with no formal education (55%). Baseline HIV knowledge was low (< 80% correct answers for 9 of the 10 questions). Knowledge gain was higher (p < 0.0001 for 8 of 10 questions) in the integrated culturally adapted and technology-facilitated (n = 511) compared with the seminar-based (n = 474) program.

Conclusions: Baseline HIV-awareness was low. Culturally …

Modeling Super-Spreading Events For Sars, Thembinkosi P. Mkhatshwa

Theses, Dissertations and Capstones

One of the intriguing characteristics of the 2003 severe acute respiratory syndrome (SARS) epidemics was the occurrence of super spreading events (SSEs). Super-spreading events for a specific infectious disease occur when infected individuals infect more than the average number of secondary cases. The understanding of these SSEs is critical to under- standing the spread of SARS. In this thesis, we present a modification of the basic SIR (Susceptible - Infected - Removed) disease model, an SIPR (Susceptible - Regular Infected - Super-spreader - Removed) model, which captures the effect of the SSEs.

A Bland–Altman Comparison Of The Lead Care® System And Inductively Coupled Plasma Mass Spectrometry For Detecting Low-Level Lead In Child Whole Blood Samples, Christina Sobin, Tanner Schaub, Natali Parisi, Eva De La Riva

Selected Works Temporary Series

Chronic childhood lead exposure, yielding blood lead levels consistently below 10 μg/dL, remains a major public health concern. Low neurotoxic effect thresholds have not yet been established. Progress requires accurate, efficient, and cost-effective methods for testing large numbers of children. The LeadCare® System (LCS) may provide one ready option. The comparability of this system to the “gold standard” method of inductively coupled plasma mass spectrometry (ICP-MS) for the purpose of detecting blood lead levels below 10 μg/dL has not yet been examined. Paired blood samples from 177 children ages 5.2–12.8 years were tested with LCS and ICP-MS. Triplicate repeat tests …

Climate Change And Sea Level Rise Initiative (Ccslri), Larry P. Atkinson

CCSLRI Brochures

Brochure of the Old Dominion University Climate Change and Sea Level Rise Initiative (CCSLRI)

Observer-Dependent Model For Analyzing Subjective Parameters In Epidemiology, Milad Zarei

Open Access Theses & Dissertations

Although medical technologies for preventing the contagion and spread of infectious diseases have improved steadily throughout the last century, new infectious diseases are still emerging and spreading swiftly. The modeling of infectious disease spread is crucial in addressing the lack of predictive ability in epidemiology. Managing the spread of infectious diseases requires processing quantitative epidemiological data and the ability to capture the dynamics of the infectious disease in order to provide a measure of control.

In this thesis, I have introducing cognitive biases in diseases spread modeling. For the first time, to the author's knowledge, the human subjective experience has …

Evaluating And Regulating Lead In Artificial Turf, Gregory Van Ulirsch, Kevin Gleason, Shawn Gerstenberger, Deaphne B. Moffett, Glenn Pulliam, Tariq Ahmed, Jerald Fagliano

Environmental & Global Health Faculty Research

Background: In 2007, a synthetic turf recreational field in Newark, New Jersey, was closed because lead was found in synthetic turf fibers and in surface dust at concentrations exceeding hazard criteria. Consequently, public health professionals across the country began testing synthetic turf to determine whether it represented a lead hazard. Currently, no standardized methods exist to test for lead in synthetic turf or to assess lead hazards.

Objectives: Our objectives were to increase awareness of potential lead exposure from synthetic turf by presenting data showing elevated lead in fibers and turf-derived dust; identify risk assessment uncertainties; recommend that federal and/or …

Pollution And Public Health In A Shrinking World: Concentrated Animal Feeding Operations As A Paradigm For Emergent Needs In Environmental And Public Health Policy, Leland Stillman

Self-Designed Majors Honors Papers

Environmental factors play a major part in human health. Environmental pollutants are often as poisonous to humans as the environment. Presently, much time and energy is dedicated to keeping pollution apart from human society, with varying success. But as global population densities rise, current levels of pollution will become inviable due to public health concerns. An emergent example of this is in the concentration of livestock operations. Recent changes in the structure of U.S. hog farming have resulted in an industry-wide shift from small or medium production farms to high capacity, “concentrated animal feeding operations” (CAFO). These operations have become …

Identifying Influential Observations Through The Intraclass Correlation Coefficient, Angel De Jesus Davalos

Open Access Theses & Dissertations

In this thesis, we analyze the performance of adapting the DFBETA statistic for identifying influential observations on the intraclass correlation coefficient under the assumptions of the one-way random effects model. Additionally, we introduce an approach for transforming negative intraclass correlation coefficient estimation values using the method of moments estimator. We apply this method on a data set of repeated blood pressure measurements, after which we will investigate implications of identifying influential observations.

On The Eigenstructures Of Functional K-Potent Matrices And Their Integral Forms, Yan Wu, Daniel F. Linder

Biostatistics: Faculty Publications

In this paper, a functional k-potent matrix satisfies the equation, where k and r are positive integers, and are real numbers. This class of matrices includes idempotent, Nilpotent, and involutary matrices, and more. It turns out that the matrices in this group are best distinguished by their associated eigen-structures. The spectral properties of the matrices are exploited to construct integral k-potent matrices, which have special roles in digital image encryption.

The Use Of Human Patient Simulators To Enhance The Clinical Decision Making Of Nursing Students, Sharon Kay Powell-Laney

Walden Dissertations and Doctoral Studies

One of the newest teaching modalities in nursing education is the use of human patient simulators (HPS). An HPS simulation scenario creates a software program vignette in which students interact with a manikin to practice caring for critical patients in a risk-free environment. Although used extensively in schools of nursing, there is little research that examines if these expensive simulators improve the clinical decision-making ability of nursing students. The purpose of this experimental differentiated treatment study was to assess if HPS technology leads to increased clinical decision-making ability and clinical performance more than the teaching modality of a paper and …

A Markov Transition Model To Dementia With Death As A Competing Event, Liou Xu

University of Kentucky Doctoral Dissertations

The research on multi-state Markov transition model is motivated by the nature of the longitudinal data from the Nun Study (Snowdon, 1997), and similar information on the BRAiNS cohort (Salazar, 2004). Our goal is to develop a flexible methodology for handling the categorical longitudinal responses and competing risks time-to-event that characterizes the features of the data for research on dementia. To do so, we treat the survival from death as a continuous variable rather than defining death as a competing absorbing state to dementia. We assume that within each subject the survival component and the Markov process are linked by …

Heat Stress Evaluation Of Protective Clothing Ensembles, Amanda Lee Pease

USF Tampa Graduate Theses and Dissertations

Clothing directly affects the level of heat stress exposure. Useful measures to express the thermal characteristics are WBGT (wet bulb globe temperature) clothing adjustment factor (CAF) or apparent total evaporative resistance (R_e,T,_a). The CAF is assigned through laboratory wear trials following a heat stress protocol in which the air temperature and humidity are progressively increased until the participant clearly loses the ability to maintain thermal equilibrium. The critical condition is the point of thermal transition and from these conditions both the CAF and Re,T,a are computed. The first objective of this study is to compare the …

Serum Antibodies To Human Papillomavirus Type 6, 11, 16 And 18 And Their Role In The Natural History Of Hpv Infection In Men, Beibei Lu

USF Tampa Graduate Theses and Dissertations

Our understanding of humoral immune response to human papillomavirus (HPV) infection has been mainly derived from studies in women. Very little is known about humoral immune response to HPV in men. There is also a growing interest in understanding the burden of HPV exposure in the subgroups of the male population, including men who have sex with women (MSW), men who have sex with men (MSM) and men who have sex with both men and women (MSMW). This dissertation was undertaken to understand and characterize humoral immune response, measured by detectable serum antibody IgG, to HPV 6, 11, 16 and …

Inadequate Health Numeracy Affects Cancer Screening Practices In Vulnerable Populations, Sherrine Eid Mph, Dorothy Faulkner Phd

Administration & Leadership

No abstract provided.

Survival Analysis With Error-Prone Time-Varying Covariates: A Risk Set Calibration Approach, Xiaomei Liao, David M. Zucker, Yi Li, Donna Spiegelman

Harvard University Biostatistics Working Paper Series

No abstract provided.

A Comparison Of Frequentist And Bayesian Approaches To The Estimation Of Long-Stay Per-Diems, Jeff Hatcher, Jason M. Sutherland

Dartmouth Scholarship

Within many diagnosis related group (DRG) systems, there is recognition that a single cost weight per DRG is not suitable, and that cost weights should take into account extremely lengthy hospital stays. Long lengths of stay are considered to be due to factors largely beyond the control of the hospital, and a single weight per DRG would potentially place hospitals under financial risk.

Within Canada's acute-care, inpatient grouping methodology - Case Mix Groups (CMG+) - long-stay episodes represent approximately 4.5% of all discharges. Within a CMG (analogous to DRG), the cost weight assigned to long-stay cases consists of the typical …

Lot Quality Assurance Sampling (Lqas) And The Mozambique Malaria Indicator Surveys, Caitlin Biedron, Marcello Pagano, Bethany L. Hedt, Albert Kilian, Amy Ratcliffe, Samuel Mabunda, Joseph J. Valadez

Harvard University Biostatistics Working Paper Series

No abstract provided.

Analysis Of Subgroup Data In Clinical Trials, Kao-Tai Tsai, Karl E. Peace

Biostatistics: Faculty Presentations (2003-2018)

This conference abstract was published in the Proceedings of the Sixteenth Annual Biopharmaceutical Applied Statistics Symposium.

Agenda: World Energy Justice Conference And Appropriate Technology Arcade, University Of Colorado Boulder. Center For Energy & Environmental Security, University Of Colorado Boulder. School Of Law

World Energy Justice Conference (October 23-24)

The 2009 CEES Energy Justice Conference took place at the University of Colorado Law School on October 23rd and 24th, 2009. It featured 11 sessions, more than 40 speakers, and attracted over 200 attendees. The Conference brought together leading international and U.S. decision-makers in politics, engineering, public health, law, business, economics, and innovators in the sciences to explore how best to address the critical needs of the energy-oppressed poor (EOP) through long-term interdisciplinary action, information sharing, and deployment of appropriate sustainable energy technologies (ASETs).

The Colorado Journal of International Environmental Law & Policy (CJIELP) at the University of Colorado Law …

Causal Inference In Epidemiological Studies With Strong Confounding, Kelly L. Moore, Romain S. Neugebauer, Mark J. Van Der Laan, Ira B. Tager

U.C. Berkeley Division of Biostatistics Working Paper Series

One of the identifiabilty assumptions of causal effects defined by marginal structural model (MSM) parameters is the experimental treatment assignment (ETA) assumption. Practical violations of this assumption frequently occur in data analysis, when certain exposures are rarely observed within some strata of the population. The inverse probability of treatment weighted (IPTW) estimator is particularly sensitive to violations of this assumption, however, we demonstrate that this is a problem for all estimators of causal effects. This is due to the fact that the ETA assumption is about information (or lack thereof) in the data. A new class of causal models, causal …