Biostatistics Commons^™

Bayesian Modeling For Longitudinal Count Data: Applications In Biomedical Research, Morshed Alam

Theses & Dissertations

Biomedical count data such as the number of seizures for epilepsy patients, number of new tumors at each visit or the number vomiting after each chemo-radiation for the cancer patients are common. Often these counts are measured longitudinally from patients or within clusters in multi-site trials. The Poisson and negative binomial models may not be adequate when data exhibit over or under-dispersion, respectively. On the contrary, a variety of dispersion conditions in count data can be captured by Conway-Maxwell Poisson (CMP) model.

This doctoral dissertation relegates to developing a statistical methodology to model longitudinal count data distributed as CMP via …

Multi-Level Small Area Estimation Based On Calibrated Hierarchical Likelihood Approach Through Bias Correction With Applications To Covid-19 Data, Nirosha Rathnayake

Theses & Dissertations

Small area estimation (SAE) has been widely used in a variety of applications to draw estimates in geographic domains represented as a metropolitan area, district, county, or state. The direct estimation methods provide accurate estimates when the sample size of study participants within each area unit is sufficiently large, but it might not always be realistic to have large sample sizes of study participants when considering small geographical regions. Meanwhile, high dimensional socio-ecological data exist at the community level, providing an opportunity for model-based estimation by incorporating rich auxiliary information at the individual and area levels. Thus, it is critical …

Cellphone Laws And Teens' Calling While Driving: Analysis Of Repeated Cross-Sectional Surveys In 2013, 2015, 2017, And 2019, Li Li, Caitlin N. Pope, Rebecca R. Andridge, Julie K. Bower, Guoqing Hu, Motao Zhu

Graduate Center for Gerontology Faculty Publications

BACKGROUND: Distracted driving among teens is a public health and safety concern. Most states in the U.S. have sought to restrict cellphone use while driving by enacting laws. This study examines the difference in prevalence of self-reported calling while driving (CWD) between states with different cellphone bans.

METHODS: Demographics and CWD data were extracted from state Youth Risk Behavior Surveys (YRBS) from 14 states in 2013, 2015, 2017, and 2019. The state YRBS is conducted every 2 years with a representative sample of 9th through 12th grade students attending public school. States were grouped by type of cellphone law(s): no …

The Effect Of Area Deprivation On Covid-19 Risk In Louisiana, Madhav Kc, Evrim Oral, Susanne Straif-Bourgeois, Ariane L. Rung, Edward S. Peters

School of Public Health Faculty Publications

Background Louisiana in the summer of 2020 had the highest per capita case count for COVID-19 in the United States and COVID-19 deaths disproportionately affects the African American population. Neighborhood deprivation has been observed to be associated with poorer health outcomes. The purpose of this study was to examine the relationship between neighborhood deprivation and COVID-19 in Louisiana. Methods The Area Deprivation Index (ADI) was calculated and used to classify neighborhood deprivation at the census tract level. A total of 17 US census variables were used to calculate the ADI for each of the 1148 census tracts in Louisiana. The …

Uganda As A Role Model For Pandemic Containment In Africa, Ahmed M. Sarki, Alex Ezeh, Saverio Stranges

Epidemiology and Biostatistics Publications

No abstract provided.

The Impact Of The Diabetes Management Incentive On Diabetes-Related Services: Evidence From Ontario, Canada., Thaksha Thavam, Rose Anne Devlin, Amardeep Thind, Gregory S Zaric, Sisira Sarma

Epidemiology and Biostatistics Publications

Financial incentives have been introduced in several countries to improve diabetes management. In Ontario, the most populous province in Canada, a Diabetes Management Incentive (DMI) was introduced to family physicians practicing in patient enrollment models in 2006. This paper examines the impact of the DMI on diabetes-related services provided to individuals with diabetes in Ontario. Longitudinal health administrative data were obtained for adults diagnosed with diabetes and their family physicians. The study population consisted of two groups: DMI group (patients enrolled with a family physician exposed to DMI for 3 years), and comparison group (patients affiliated with a family physician …

Participatory Video As A Novel Recovery-Oriented Intervention In Early Psychosis: A Pilot Study., Arlene G Macdougall, Sahana Kukan, Elizabeth Price, Sarah Glen, Richelle Bird, Laura Powe, Joshua C. Wiener, Paul H Lysaker, Kelly K Anderson, Ross Mg Norman

Epidemiology and Biostatistics Publications

BACKGROUND: Personal narrative plays an important role in the process of recovery from psychotic illnesses. Participatory video is a novel, active intervention that can be used as a tool for fostering narrative development among people with psychosis.

AIM: To assess the feasibility, acceptability and potential clinical utility of participatory video as an innovative tool for promoting recovery in early psychosis.

METHODS: Ten outpatients of an early psychosis intervention programme were recruited to participate in 13 biweekly workshops to plan, film and produce documentary-style videos of their experiences. Feasibility was measured through recruitment and retention. Acceptability was measured through workshop attendance …

Gene Set Testing By Distance Correlation, Sho-Hsien Su

Graduate Theses and Dissertations

Pathways are the functional building blocks of complex diseases such as cancers. Pathway-level studies may provide insights on some important biological processes. Gene set test is an important tool to study the differential expression of a gene set between two groups, e.g., cancer vs normal. The differential expression of a gene set could be due to the difference in mean, variability, or both. However, most existing gene set tests only target the mean difference but overlook other types of differential expression. In this thesis, we propose to use the recently developed distance correlation for gene set testing. To assess the …

Conditional Distance Correlation Test For Gene Expression Level, Dna Methylation Level And Copy Number, Shanshan Zhang

Graduate Theses and Dissertations

Over the past years, efforts have been devoted to the genome-wide analysis of genetic and epigenetic profiles to better understand the underlying biological mechanisms of complex diseases such as cancer. It is of great importance to unravel the complex dependence structure between biological factors, and many conditional dependence tests have been developed to meet this need. The traditional partial correlation method can only capture the linear partial correlation, but not the nonlinear correlation. To overcome this limitation, we propose to use the innovative conditional distance correlation (CDC), which measures the conditional dependence between random vectors and detect nonlinear relations. In …

Modified-Half-Normal Distribution And Different Methods To Estimate Average Treatment Effect., Jingchao Sun

Electronic Theses and Dissertations

This dissertation consists of three projects related to Modified-Half-Normal distribution and causal inference. In my first project, a new distribution called Modified-Half-Normal distribution was introduced. I explored a few of its distributional properties, the procedures for generating random samples based on Bayesian approaches, and the parameter estimation based on the method of moments. The second project deals with the problem of selection bias of average treatment effect (ATE) if we use the observational data. I combined the propensity score based inverse probability of treatment weighting (IPTW) method and the directed acyclic graph (DAG) to solve this problem. The third project …

Statistical Approaches Of Gene Set Analysis With Quantitative Trait Loci For High-Throughput Genomic Studies., Samarendra Das

Electronic Theses and Dissertations

Recently, gene set analysis has become the first choice for gaining insights into the underlying complex biology of diseases through high-throughput genomic studies, such as Microarrays, bulk RNA-Sequencing, single cell RNA-Sequencing, etc. It also reduces the complexity of statistical analysis and enhances the explanatory power of the obtained results. Further, the statistical structure and steps common to these approaches have not yet been comprehensively discussed, which limits their utility. Hence, a comprehensive overview of the available gene set analysis approaches used for different high-throughput genomic studies is provided. The analysis of gene sets is usually carried out based on …

Aspects Of Causal Inference., John A. Craycroft

Electronic Theses and Dissertations

Observational studies differ from experimental studies in that assignment of subjects to treatments is not randomized but rather occurs due to natural mechanisms, which are usually hidden from researchers. Yet objectives of the two studies are frequently the same: identify the causal – rather than merely associational – relationship between some treatment or exposure and an outcome. The statistical issues that arise in properly analyzing observational data for this goal are numerous and fascinating, and these issues are encompassed in the domain of causal inference. The research presented in this dissertation explores several distinct aspects of causal inference. This dissertation …

Gardasil Vaccine Trends Within Nevada, California, And The U.S.: A Comparative Study, Karen S. Gutierrez

UNLV Theses, Dissertations, Professional Papers, and Capstones

Despite decreasing incidence in cervical cancer in the U.S., there continues to be an increase in public health concern for cervical cancer worldwide. Recent studies report that individuals are disproportionately affected based on region, sex, and race. Additionally, the human papillomavirus (HPV) attributable cancers may be reduced between 70% and 90% through the universal use of HPV-vaccines. In order to expand current knowledge and implement intervention programs in Nevada, it is critical to examine the associations among the Gardasil vaccine, cervical cancer screening, and adverse events following immunization as well as to understand the different socio-demographic subgroups affected. To our …

When Will The Covid-19 Pandemic In Indonesia End?, Dewi Susanna

Kesmas

On January 30, 2020, the World Health Organization(WHO) declared 2019-nCOV to be a Public Health Emergency of International Concern (PHEIC), due to the significant increase in confirmed new cases in various countries.1 In Indonesia, the first confirmed COVID-19 case was a female who had a closed contact with the 24th confirmed case in Malaysia and the second case was the mother of the first case.2 As time goes by, the number of new cases has increased significantly, reaching 160.165 confirmed cases with 6,944 deaths by August 27, 2020.3 The time when the COVID-19 pandemic in Indonesia will end is not …

Obesity Indicators And C-Reactive Protein In Indonesian Adults (More Than Equal To 40 Years Old): The Indonesian Family Life Survey 5, Yeni Mahwati, Dieta Nurrika

Kesmas

C-reactive protein (CRP) is the best clinical marker for systemic inflammation. Obesity is associated with increased CRP levels. Systemic inflammation is present before morbidity occurs. Research reveals that the identification of obesity indicators and CRP levels is limited among Indonesians. The present study investigated the associations between obesity indicators (body mass index [BMI], waist circumference [WC], waist-to-hip ratio [WHR], waist-to-height ratio [WHtR]) and CRP levels among Indonesian adults. This cross-sectional study based on Indonesian Family Life Survey-5 2014–2015 was conducted among 3,386 adults (≥ 40 years) living in 13 provinces in Indonesia during the study period. All data were collected …

Using The Reach, Effectiveness, Adoption, Implementation, Maintenance Framework In The Evaluation Of Community-Based Adolescent Care Pilot Program, Badra Al Aufa, Wahyu Sulistiadi, Mochamad Iqbal Nurmansyah, Agung T R Syiroj, Ibrahim Isa Koire

Kesmas

Posyandu Remaja (Posmaja) is a community-based adolescent care service in Indonesia that comprises a group of adolescents working as volunteers and healthcare workers under the guidance and responsibility of the Public Health Centre and City Health Office. The study aims to provide a formative evaluation program of Posmaja using the Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) framework. This research used a qualitative approach and took place in South Tangerang City, Indonesia. The data were collected from July until December 2018. Nineteen people participated in the study. The study used in-depth interviews and focus group discussions that adopted the RE-AIM …

A Study On Knowledge, Attitudes, And Practices On Rabies In The Philippines, Reynaldo Jr Bundalian, Monalisa Lacson, Catherine Bacani, Dinah Rose Soriano, Agnes Garing, Artemio Jr Aquino, Archie Policarpio, Joey Kyle Mallari, Remedios San Jose, Maria Fe Bulao, Neil Tanquilut, Patricia Joy Magsino

Kesmas

In 2007, the Philippine government passed the Anti-Rabies Act to address rabies in the country. However, rabies is still a major public health concern in many provinces. This study aimed to evaluate the knowledge, attitude, and practices (KAP) of residents on rabies, the Anti Rabies Act, and responsible pet ownership (RPO) in Pampanga, Philippines. A cross-sectional survey was done from October 2017 to February 2018 in 92 randomly selected barangays in the province. Questionnaires were adapted from similar studies. Logistic regression was used to identify factors associated with KAP. Results showed that most people have good knowledge of the Anti-Rabies …

Cultural And Religious Belief Approaches Of A Tuberculosis Program For Hard-To-Reach Populations In Mentawai And Solok West Sumatera, Indonesia, Rizanda Machmud, Irvan Medison, Finny Fitry Yani

Kesmas

Tuberculosis (TB) is a leading public health concern in Indonesia. It ranks second on the list of high-burden TB countries. In West Sumatra, 47% of TB cases are undetected, late diagnosed, and received incomplete treatment because of low-level awareness and knowledge and stigma, especially among the hardest to reach populations. The study aims to identify the best communication channel to reach those who live in vulnerable and remote areas. This study was a qualitative study applying in-depth interviews to the informal leaders, health officers, cultural artists, and religious leaders across districts in Mentawai and Solok Districts, which are remote and …

Policy Implementation: Teachers’ Role As First Responders In Emergencies And Disasters, Shabir Hyder, Adnan Fazal Manzoor, Muhammad Amjad Iqbal

Kesmas

During the past decade, the schoolchildren faced many disasters and emergencies originating from natural and man-made sources. The safety of schoolchildren rests with school management and teachers. This study aimed to assess teachers' awareness with regard to disaster prevention and health, safety, security, and environment (HSSE) policies at primary schools in Pakistan. In addition, it explores the suitability of teachers to perform as emergency handlers in the absence of school nurses and resource officers (SROs). The study involved a qualitative study, based on open-ended interviews from a sample of 25 school teachers. Methodology triangulation was applied to reduce bias. Results …

Association Between Social Media Exposure To Food And Beverages With Nutrient Intake Of Female Adolescents, Cholida Adiba, Siti Fatimah Pradigdo, Martha Irene Kartasurya

Kesmas

Communication technology development has influenced adolescent food choices and intakes. This study aimed to investigate the association between social media exposure to food and beverage content and nutrient intake among female adolescents. The study was conducted in a cross-sectional design. The targeted population was 104 female students aged 14–18 years old at 'XY' High School in Semarang, Central Java, Indonesia. Eighty-one subjects were chosen by clustered random sampling. Data were collected by interviews using structured questionnaires and a 3x24-hour recall method. Data analyses were conducted by chi-square, Fisher exact tests, and logistic regression. The median and standard deviations of social-media, …

Ultraviolet Exposure And Photokeratitis Complaints Among Informal Welding Workers In Depok, West Java, Indonesia, Maria K I J Yustheresani, Fajaria Nurcandra, Azizah Musliha Fitri, Annisa Ika Putri, Dyah Utari

Kesmas

One of the photokeratitis risk factors is acute reversible radiation of ultraviolet (UV) rays, which injure the cornea's epithelial tissue. Informal welding workers are susceptible populations to UV rays exposure. This study aimed to confirm the influence of UV radiation exposure on photokeratitis complaints in welding workers in Cimanggis, Depok, West Java. A cross-sectional study was conducted from February to June 2019 and used to select 100 welding workers purposively. A semi-structured questionnaire was used to determine photokeratitis complaints, age, education level, eye protection, safety knowledge, and work period; the UV radiation measured by A UV meter. Data were analyzed …

Assessment Of Knowledge, Attitudes, And Behaviors Of Turkish Women On Breast And Cervical Cancer In Karabük Province, Turkey, Nergiz Sevinc, Belgin Oral, Burcu Korkut

Kesmas

Breast and cervical cancer incidence and mortality among women have been increasing worldwide. This cross-sectional study aimed to evaluate women's knowledge, attitudes, and behaviors regarding breast and cervical cancers. The sample was composed of 507 women aged 18 years and older who were admitted to a primary health care center in Karabük, Turkey, from October to December 2019. The data was obtained using a questionnaire consisting of 34 questions regarding participants’ socio demographic characteristics, knowledge, attitudes, and behaviors toward breast and cervical cancers. The mean age of the participants was 41.3±12.0 years and 68.4% of them were married. Slightly more …

Direct Questioning Of Sensitive Topics In Public Health Studies: A Simulation Study, Jessica K. Fox, Evrim Oral

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Evidence Of Nickel And Other Trace Elements And Their Relationship To Clinical Findings In Acute Mesoamerican Nephropathy: A Case-Control Analysis, Rebecca S. B. Fischer, Jason M. Unrine, Chandan Vangala, Wayne T. Sanderson, Sreedhar Mandayam, Kristy O. Murray

Plant and Soil Sciences Faculty Publications

BACKGROUND: Although there are several hypothesized etiologies of Mesoamerican Nephropathy (MeN), evidence has not yet pointed to the underlying cause. Exposure to various trace elements can cause the clinical features observed in MeN.

METHODS AND FINDINGS: We measured 15 trace elements, including heavy metals, in renal case-patients (n = 18) and healthy controls (n = 36) in a MeN high-risk region of Nicaragua. Toenails clippings from study participants were analyzed using inductively coupled plasma mass spectrometry. A case-control analysis was performed, and concentrations were also analyzed over participant characteristics and clinical parameters. Nickel (Ni) concentrations were significantly higher in toenails …

Implementation And Sustainment Of A Statewide Telemedicine Diabetic Retinopathy Screening Network For Federally Designated Safety-Net Clinics, Ana Bastos De Carvalho, S. Lee Ware, Feitong Lei, Heather M. Bush, Robert Sprang, Eric B. Higgins

Ophthalmology and Visual Science Faculty Publications

CONTEXT: Diabetic retinopathy (DR) is the leading cause of incident blindness among working-age adults in the United States. Federally designated safety-net clinics (FDSC) often serve as point-of-contact for patients least likely to receive recommended DR screenings, creating opportunity for targeted interventions to increase screening access and compliance.

STUDY DESIGN AND METHODS: With such a goal, we implemented and assessed the longitudinal performance of an FDSC-based telemedicine DR screening (TDRS) network of 22 clinical sites providing nonmydriatic fundus photography with remote interpretation and reporting. Retrospective analysis of patient encounters between February 2014 and January 2019 was performed to assess rates of …

Blood Pressure Monitoring Following Individual Carpules Of Anesthetic Utilizing Computer-Controlled Anesthetic Delivery, Kristi M. Soileau, Adam E. Degenova, Qingzhao Yu

School of Dentistry Faculty Publications

To date, no study has evaluated blood pressure following administration of each carpule given for dental procedures using a computerized dental anesthesia system. Blood pressures taken prior to performing invasive periodontal procedures were compared with those readings measured following delivery of each of up to three consecutive carpules of Marcaine or Xylocaine in varying order. Pressure differences were also adjusted for age, sex, race, and whether a prescribed anxiolytic was taken beforehand. Neither systolic nor diastolic blood pressures changed significantly as compared to initial blood pressure readings. However, compared with Whites, Hispanics, and Middle Easterners, Blacks had significantly higher systolic …

Stirring The Pot: Switching From Blended Fee-For-Service To Blended Capitation Models Of Physician Remuneration., Nibene H Somé, Rose Anne Devlin, Nirav Mehta, Gregory S Zaric, Sisira Sarma

Epidemiology and Biostatistics Publications

In Canada's most populous province, Ontario, family physicians may choose between the blended fee-for-service (Family Health Group [FHG]) and blended capitation (Family Health Organization [FHO] payment models). Both models incentivize physicians to provide after-hours (AH) and comprehensive care, but FHO physicians receive a capitation payment per enrolled patient adjusted for age and sex, plus a reduced fee-for-service while FHG physicians are paid by fee-for-service. We develop a theoretical model of physician labor supply with multitasking to predict their behavior under FHG and FHO, and estimable equations are derived to test the predictions empirically. Using health administrative data from 2006 to …

Distinct Clinicopathologic Clusters Of Persons With Tdp-43 Proteinopathy, Yuriko Katsumata, Erin L. Abner, Shama Karanth, Merilee A. Teylan, Charles N. Mock, Matthew D. Cykowski, Edward B. Lee, Kevin L. Boehme, Shubhabrata Mukherjee, John S. K. Kauwe, Richard J. Kryscio, Frederick A. Schmitt, David W. Fardo, Peter T. Nelson

Biostatistics Faculty Publications

To better understand clinical and neuropathological features of TDP-43 proteinopathies, data were analyzed from autopsied research volunteers who were followed in the National Alzheimer’s Coordinating Center (NACC) data set. All subjects (n = 495) had autopsy-proven TDP-43 proteinopathy as an inclusion criterion. Subjects underwent comprehensive longitudinal clinical evaluations yearly for 6.9 years before death on average. We tested whether an unsupervised clustering algorithm could detect coherent groups of TDP-43 immunopositive cases based on age at death and extensive neuropathologic data. Although many of the brains had mixed pathologies, four discernible clusters were identified. Key differentiating features were age at …

The Use Of Penalized Regression Analysis To Identify County-Level Demographic And Socioeconomic Variables Predictive Of Increased Covid-19 Cumulative Case Rates In The State Of Georgia, Holly L. Richmond, Joana Tome, Haresh Rochani, Isaac Chun-Hai Fung, Gulzar H. Shah, Jessica S. Schwind

Biostatistics, Epidemiology & Environmental Health Sciences: Faculty Publications

Systemic inequity concerning the social determinants of health has been known to affect morbidity and mortality for decades. Significant attention has focused on the individual-level demographic and co-morbid factors associated with rates and mortality of COVID-19. However, less attention has been given to the county-level social determinants of health that are the main drivers of health inequities. To identify the degree to which social determinants of health predict COVID-19 cumulative case rates at the county-level in Georgia, we performed a sequential, cross-sectional ecologic analysis using a diverse set of socioeconomic and demographic variables. Lasso regression was used to identify variables …

Multi-Ancestry Genome-Wide Association Study Accounting For Gene-Psychosocial Factor Interactions Identifies Novel Loci For Blood Pressure Traits, Daokun Sun, Melissa A. Richard, Soloman K. Musani, Yun Ju Sung, Thomas W. Winkler, Karen Schwander, Jin Fang Chai, Xiuqing Guo, Tuomas O. Kilpeläinen, Dina Vojinovic, Hugues Aschard, Traci M. Bartz, Lawrence F. Bielak, Michael R. Brown, Kumaraswamy Chitrala, Fernando P. Hartwig, Andrea R. V. R. Horimoto, Yongmei Liu, Alisa K. Manning, Raymond Noordam, Donna K. Arnett

Epidemiology and Environmental Health Faculty Publications

Psychological and social factors are known to influence blood pressure (BP) and risk of hypertension and associated cardiovascular diseases. To identify novel BP loci, we carried out genome-wide association meta-analyses of systolic, diastolic, pulse, and mean arterial BP, taking into account the interaction effects of genetic variants with three psychosocial factors: depressive symptoms, anxiety symptoms, and social support. Analyses were performed using a two-stage design in a sample of up to 128,894 adults from five ancestry groups. In the combined meta-analyses of stages 1 and 2, we identified 59 loci (p value < 5e−8), including nine novel BP loci. The novel associations were observed mostly with pulse pressure, with fewer observed with mean arterial pressure. Five novel loci were identified in African ancestry, and all but one showed patterns of interaction with at least one psychosocial factor. Functional annotation of the novel loci supports a major role for genes implicated in the immune response (PLCL2), synaptic function and neurotransmission (LIN7A …