Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 14 of 14
Full-Text Articles in Entire DC Network
Association Of Blood Pressure Phenotypes With Kidney Disease, Rikki M. Tanner
Association Of Blood Pressure Phenotypes With Kidney Disease, Rikki M. Tanner
All ETDs from UAB
Kidney disease is common, with recent estimates indicating a prevalence of 13% among US adults. Furthermore, the vast majority of individuals with kidney disease have hypertension. Apparent treatment-resistant hypertension (aTRH), 24-hour blood pressure (BP) variability, and inter-arm differences (IADs) in BP have been identified as risk factors for cardiovascular disease, and there is increasing evidence that these phenotypes provide prognostic information above and beyond mean clinic BP. However, these phenotypes have not been extensively studied among individuals with kidney disease. The goal of this dissertation was to determine the association of kidney disease with BP phenotypes in the context of …
Acculturation And Social Support As Predictors Of Physical Activity In A Web-Based Intervention For Latinas, Tanya Benitez
Acculturation And Social Support As Predictors Of Physical Activity In A Web-Based Intervention For Latinas, Tanya Benitez
All ETDs from UAB
Latinas in the United States report high levels of physical inactivity and are disproportionately burdened by associated chronic diseases, demonstrating the need for innovative approaches to reducing these disparities. The purpose of the current study was to evaluate self-reported changes in physical activity and social support, and to examine the association between physical activity and acculturation, following a one month culturally and linguistically adapted, theory-driven (Social Cognitive Theory and Transtheoretical Model) Internet-based physical activity intervention for Latina adults. Data was collected from Spanish-speaking Latinas (N=24) between the ages of 21-61 years (M=35.17, SD=11.22) enrolled in a web-based physical activity pilot …
Predictors Of Outcomes In Patients With Ventricular Assist Devices, Amelia Katharine Boehme
Predictors Of Outcomes In Patients With Ventricular Assist Devices, Amelia Katharine Boehme
All ETDs from UAB
Ventricular assist devices (VAD) are used as a bridge to transplant and to increase the quality of life in advanced heart failure patients. The use of the VAD is not without risks itself, with an increased risk of thromboembolism, hemorrhage and death. Therefore, we aimed to (1) evaluate predictors of thromboembolism; (2) design a score to predict hemorrhages in VAD patients; and (3) evaluate the change in kidney function post-VAD implant and to investigate the relationship between kidney function and mortality in VAD patients using data collected from the University of Alabama at Birmingham Mechanical Circulatory Support Clinic. Over the …
New Niosh Headforms: Developing Novel Methods For Fabricating A More Realistic Physical Headform And Custom Facepieces And Evaluating Existing Commercially-Available Respirators, Paula Susanne Joe
All ETDs from UAB
For over 30 years, respirator sizing has been based on an anthropometric survey performed by LANL using the young and predominantly Caucasian US Air Force personnel. NIOSH, having observed the increase in diversity in the workplace, began a new survey in 2003 weighted to the US census. Finding that the LANL panel was no longer representative of the modern workforce, a new fit test panel recommending five sizing categories was created in 2007. Anthropometrically accurate headforms three-dimensional models for the average face in each size were designed in 2010. While these headforms are intended for use in respirator design, it …
Power Issues And Internal Pilot Designs For Cluster-Randomized Trials With Unequal Cluster Sizes, Ashutosh Ranjan
Power Issues And Internal Pilot Designs For Cluster-Randomized Trials With Unequal Cluster Sizes, Ashutosh Ranjan
All ETDs from UAB
Cluster-randomized trials that randomize groups of individuals, instead of individuals themselves, run the risk of being underpowered when they are designed assuming equal cluster sizes but end up recruiting unequal clusters. The loss in power of the trial is directly related to the amount of variation present among the cluster sizes. To overcome the loss in power, researchers often employ a weighted analysis of the cluster means. Different weighting procedures have been developed that appear to maintain the power of the trial but there have been fewer attempts to describe the impact of different weights on the type I error …
Predictors Of Smoking Cessation Among Dental Patients Participating In A Web-Assisted Tobacco Intervention: A National Dental Practice-Based Research Network Study, Midge N. Ray
All ETDs from UAB
MIDGE N. RAY HEALTH PROMOTION AND EDUCATION ABSTRACT Nicotine addiction is a chronic and relapsing disease that has serious health consequences. Tobacco continues to be the leading preventable cause of morbidity and mortality in the United States. In 2010, approximately 58.3 million Americans were identified as cigarette smokers. This study was part of the Hygienists' Internet Tobacco Cessation Study (Hi Quit), a randomized controlled trial that employed a web-assisted tobacco intervention (WATI) called Decide2Quit to assist smokers in quitting. Smokers (N=258) were enrolled in the study by dental practices (N=100) that referred patients who smoke to the website. The control …
Molecular Profiling In Cervical Carcinogenesis And Progression, Kathryn Elizabeth Royse
Molecular Profiling In Cervical Carcinogenesis And Progression, Kathryn Elizabeth Royse
All ETDs from UAB
Coexisting lesions can reduce genomic heterogeneity in precancer progression analysis by reducing variation and bias that can mask gene effects. Our goal was to use novel methodologies to depict the neoplastic stage effect (Normal v. LSIL v. HSIL) in cervical precancer. We analyzed the neoplastic stage effect via in silico and in vivo methodologies. For in silico analyses, we calculated differential expression (DE) estimates from a systematic review of DNA methylation and gene expression literature. Significant genes (FC≤2.0 or p-value≥0.05) were grouped by histology for pathway analysis. For in vivo analyses, we performed RNA-seq on microdissected FFPE coexisting cervical tissue …
Exposure To Methylmercury Via Fish Consumption In Ghana And An Evaluation Of Methylmercury Toxicity Under A Low Food Ration In Daphnia Pulex, Dzigbodi Adzo Doke
Exposure To Methylmercury Via Fish Consumption In Ghana And An Evaluation Of Methylmercury Toxicity Under A Low Food Ration In Daphnia Pulex, Dzigbodi Adzo Doke
All ETDs from UAB
For many people of the world, fish is a primary source of protein, especially in countries like Ghana, where about 60% of the protein consumed is derived from fish. Fish advisories have been established by some nations to protect the public from harmful health effects linked to eating contaminated fish. Methylmercury (MeHg) is one such contaminant that has resulted in fish advisories. Fish advisories have not been developed in Ghana, although MeHg contamination of aquatic ecosystems is likely due to the long history of mercury (Hg) use in artisanal gold mining. To address this gap in our knowledge, I compiled …
Statistical Methods For Set-Based Association Tests In Genetic Studies, Qi Yan
Statistical Methods For Set-Based Association Tests In Genetic Studies, Qi Yan
All ETDs from UAB
This dissertation research focuses on developing statistical methods for set-based association tests at both pathway and gene levels in genetic studies. Set based analysis considers the biological hierarchical structure, while traditional genome-wide association studies usually focus on single-marker analysis which only access marginal effect. Therefore, pathway analysis may potentially complement single-marker analysis and provide additional insights for the genetic architecture of complex diseases. In the first study, we propose a novel way for pathway analysis that assesses the effects of genes using the sequence kernel association test (SKAT) and the effects of pathways via an extended adaptive-rank-truncated product statistic. For …
A Mixed Methods Study Of Health Literacy And Its Role In Hpv Vaccine Uptake Among College Students, Michelle Sharonda Williams
A Mixed Methods Study Of Health Literacy And Its Role In Hpv Vaccine Uptake Among College Students, Michelle Sharonda Williams
All ETDs from UAB
Health literacy includes the ability to understand and process written and spoken health information, and numbers and calculations related to health information. Low health literacy is associated with negative health outcomes, and poor patient-provider communication. In order to advance health literacy research, there is a need to assess health literacy comprehensively and to develop an understanding of how health literacy impacts people at various stages of their lives. A sequential explanatory mixed methods study was conducted to assess college students' health literacy. During the quantitative phase, the Short Test of Functional Health Literacy in Adults (S-TOFHLA), the Newest Vital Sign …
Statistical Analysis In Genomic Studies, Guodong Wu
Statistical Analysis In Genomic Studies, Guodong Wu
All ETDs from UAB
Next-generation sequencing (NGS) technologies reveal unprecedented insights about genome, transcriptome, and epigenome. However, existing quantification and statistical methods are not well prepared for the coming deluge of NGS data. In this dissertation, we propose to develop powerful new statistical methods in three aspects. First, we propose a Hidden Markov Model (HMM) in Bayesian framework to quantify methylation levels at base-pair resolution by NGS. Second, in the context of exome-based studies, we develop a general simulation framework that distributes total genetic effects hierarchically into pathways, genes, and individual variants, allowing the extensive evaluation of existing pathway-based methods. Finally, we develop a …
A Spatiotemporal Model For Repeated Imaging Data, Brandon George
A Spatiotemporal Model For Repeated Imaging Data, Brandon George
All ETDs from UAB
Longitudinal imaging studies have increased in popularity as clinical researchers seek to investigate how phenomena within the body change over time. Analysis of data from these studies is complicated by correlation between repeated measures over time and different locations in the body. To address this problem we propose the use of a linear model with a separable parametric correlation structure. This model considers spatial and temporal correlation independently and incorporates the correlation using parametric functions that have the potential to be much more efficient than an unstructured approach. Our model also has the ability to control for time- and space-varying …
An Evaluation Of Sample Size Re-Estimation Adaptive Designs And Delayed-Start Designs For Alzheimer's Disease Trials, Guoqiao Wang
An Evaluation Of Sample Size Re-Estimation Adaptive Designs And Delayed-Start Designs For Alzheimer's Disease Trials, Guoqiao Wang
All ETDs from UAB
The goal of this dissertation is to investigate the effect of novel clinical trial designs for Alzheimer's disease (AD), and to provide applications for their use in real trials. The data used for our simulation is a meta-data base of completed trials. In the first paper, we investigate the sample size re-estimation (SSR) adaptive design based on the effect size and the variance without taking into account the longitudinal feature of the trials. In the second paper, we take advantage of that feature to explore the SSR based on the variance of the rate of change in the longitudinal measurements. …
The Small Sample Inferences Of Cluster-Randomized Trials, Peng Li
The Small Sample Inferences Of Cluster-Randomized Trials, Peng Li
All ETDs from UAB
Generalized estimating equation (GEE) and generalized linear mixed model (GLMM) are two statistical modeling methods commonly used in the analyses of correlated outcomes from cluster-randomized trials (CRTs). The fact that most CRTs involve only a small number of clusters makes the small sample adjustment critical to preserve the type I error rates in testing the null hypothesis of intervention effects. To improve the small sample performance of GEE, some bias-corrected sandwich estimators have been proposed. To improve the small sample performance of GLMM, the approximated Wald F test is used to replace the asymptotic ÷^2 test and the denominator degrees …