Statistics and Probability Commons^™

In Memoriam: Irina V. Tarasevich, Marina Eremeeva

Biostatistics, Epidemiology & Environmental Health Sciences: Faculty Publications

Article published in New Microbes and New Infections.

Demonstrating The Efficacy Of The Health Sciences And Technology Academy: Using Archival Standardized Test Scores To Analyze An Ost College-Preparatory Program For Underserved Youth, Feon Smith, Sherron Mckendall, Ann Chester, Bethany Hornbeck, Alan Mckendall

Faculty & Staff Scholarship

To combat educational and health disparities, out-of-school-time (OST) STEM enrichment programs provide services to underserved youth to encourage them to pursue college and health careers. This article describes a study conducted to determine if the Health Sciences and Technology Academy (HSTA) program participants who receive year-round educational interventions to prepare them for STEM and health sciences majors performed better on the West Virginia Educational Standards Test (WESTEST2) than non-participants. This study provides descriptive and inferential statistics, specifically one-way ANOVAs with one-to-one matching based on grade level, gender, race, and GPA at the end of the 8th grade year for 336 …

Systemic Immunosuppression And Risk Of Age-Related Macular Degeneration, Harpal S. Sandhu, Joshua Lambert, Yan Xu, Henry J. Kaplan

Applied Statistics Laboratory Faculty Publications

A local immune response has been implicated in the pathogenesis of age-related macular degeneration (AMD), but it is unclear if systemic immunosuppressive/immunomodulatory therapy (IMT) protects against the onset and/or progression of AMD. We performed a retrospective cohort study using a Cox proportional hazards model of two cohorts. Cohort 1 included patients with stage V chronic kidney disease (CKD) status post kidney transplantation, on at least one IMT agent, and older than 50. Cohort 2 included patients with stage IV or V CKD who had not undergone kidney transplantation, were not on IMT, and were older than 50. The main outcomes …

Comprehensive Evaluation Of Treatment And Outcomes Of Low-Grade Diffuse Gliomas, Catherine R. Garcia, Stacey A. Slone, Thomas A. Pittman, William H. St. Clair, Donita D. Lightner, John L. Villano

Markey Cancer Center Faculty Publications

Background

Low-grade gliomas affect younger adults and carry a favorable prognosis. They include a variety of biological features affecting clinical behavior and treatment. Having no guidelines on treatment established, we aim to describe clinical and treatment patterns of low-grade gliomas across the largest cancer database in the United States.

Methods

We analyzed the National Cancer Database from 2004 to 2015, for adult patients with a diagnosis of World Health Organization grade II diffuse glioma.

Results

We analyzed 13,621 cases with median age of 41 years. Over 56% were male, 88.4% were white, 6.1% were black, and 7.6% Hispanic. The most …

Longitudinal Data Methods For Evaluating Genome-By-Epigenome Interactions In Families, Justin C. Strickland, I-Chen Chen, Chanung Wang, David W. Fardo

Psychology Faculty Publications

Background: Longitudinal measurement is commonly employed in health research and provides numerous benefits for understanding disease and trait progression over time. More broadly, it allows for proper treatment of correlated responses within clusters. We evaluated 3 methods for analyzing genome-by-epigenome interactions with longitudinal outcomes from family data.

Results: Linear mixed-effect models, generalized estimating equations, and quadratic inference functions were used to test a pharmacoepigenetic effect in 200 simulated posttreatment replicates. Adjustment for baseline outcome provided greater power and more accurate control of Type I error rates than computation of a pre-to-post change score.

Conclusions: Comparison of all modeling approaches indicated …

Gaw20: Methods And Strategies For The New Frontiers Of Epigenetics And Pharmacogenomics, Nathan L. Tintle, David W. Fardo, Marzia De Andrade, Stella Aslibekyan, Julia N. Bailey, Justo Lorenzo Bermejo, Rita M. Cantor, Saurabh Ghosh, Philip Melton, Xuexua Wang, Jean W. Maccluer, Laura Almasy

Biostatistics Faculty Publications

GAW20 provided a platform for developing and evaluating statistical methods to analyze human lipid-related phenotypes, DNA methylation, and single-nucleotide markers in a study involving a pharmaceutical intervention. In this article, we present an overview of the data sets and the contributions analyzing these data. The data, donated by the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) investigators, included data from 188 families (N = 1105) which included genome-wide DNA methylation data before and after a 3-week treatment with fenofibrate, single-nucleotide polymorphisms, metabolic syndrome components before and after treatment, and a variety of covariates. The contributions from individual …

Association Analyses Of Repeated Measures On Triglyceride And High-Density Lipoprotein Levels: Insights From Gaw20, Saurabh Ghosh, David W. Fardo

Biostatistics Faculty Publications

Background: The GAW20 group formed on the theme of methods for association analyses of repeated measures comprised 4sets of investigators. The provided “real” data set included genotypes obtained from a human whole-genome association study based on longitudinal measurements of triglycerides (TGs) and high-density lipoprotein in addition to methylation levels before and after administration of fenofibrate. The simulated data set contained 200 replications of methylation levels and posttreatment TGs, mimicking the real data set.

Results: The different investigators in the group focused on the statistical challenges unique to family-based association analyses of phenotypes measured longitudinally and applied a wide spectrum of …

Genetics Analysis Workshop 20: Methods And Strategies For The New Frontiers Of Epigenetics And Pharmacogenomics, Nathan L. Tintle, David W. Fardo, Mariza De Andrade, Stella Aslibekyan, Julia N. Bailey, Justo Lorenzo Bermejo, Rita M. Cantor, Saurabh Ghosh, Philip Melton, Xuexia Wang, Jean W. Maccluer, Laura Almasy

Faculty Work Comprehensive List

GAW20 provided a platform for developing and evaluating statistical methods to analyze human lipid-related phenotypes, DNA methylation, and single-nucleotide markers in a study involving a pharmaceutical intervention. In this article, we present an overview of the data sets and the contributions analyzing these data. The data, donated by the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) investigators, included data from 188 families (N = 1105) which included genome-wide DNA methylation data before and after a 3-week treatment with fenofibrate, single-nucleotide polymorphisms, metabolic syndrome components before and after treatment, and a variety of covariates. The contributions from individual …

Latent Tuberculosis Infection Is Associated With Increased Unstimulated Levels Of Interferon-Gamma In Lima, Peru, Moises A. Huaman, David Henson, Paola L. Rondan, Eduardo Ticona, Gustavo Miranda, Richard J. Kryscio, Raquel Mugruza, Ernesto Aranda, Cesar Ticona, Susan Abarca, Paula Heredia, Andres Aguirre, Timothy R. Sterling, Beth A. Garvy, Carl J. Fichtenbaum

Internal Medicine Faculty Publications

Background

We previously reported increased unstimulated blood levels of interferon-gamma in persons with latent tuberculosis infection (LTBI) in the United States, suggesting enhanced immune activation in LTBI. To investigate this further in a TB-endemic setting, we assessed interferon-gamma levels in persons with and without LTBI in Peru.

Methods

We analyzed data from patients with and without a recent type 1 (spontaneous) acute myocardial infarction (AMI) who were enrolled from two public hospital networks in Lima, Peru, and underwent LTBI testing using the QuantiFERON® TB Gold In-tube (QFT) assay. Participants with a positive QFT test were defined as having LTBI, whereas …

The Impact Of Peer Support On The Risk Of Future Hospital Readmissions Among Older Adults With A Medical Illness And Co-Occurring Depression, Kyaien O. Conner, Tamara Cadet, Monique J. Brown, Joshua T. Barnett

Faculty Publications

Older adults account for 60% of all preventable hospital readmissions. Although not all readmissions are preventable, evidence indicates that up to 75% of hospital readmissions can be prevented with enhanced patient education, pre-discharge assessment, and effective care upon discharge. Social support, specifically peer support, after discharge from hospital may be a crucial factor in minimizing the risk of preventable hospital readmission. The pilot study reported here evaluated the relationship between peer support and hospital readmissions in a sample of depressed older adults (N = 41) who were recently discharged from hospital due to a medical condition and who simultaneously had …

Effects Of The Affordable Care Act On Health Care Access And Self-Assessed Health After 3 Years, Charles J. Courtemanche, James Marton, Benjamin Ukert, Aaron Yelowitz, Daniela Zapata

Economics Faculty Publications

Using data from the Behavioral Risk Factor Surveillance System, we examine the causal impact of the Affordable Care Act on health-related outcomes after 3 years. We estimate difference-in-difference-in-differences models that exploit variation in treatment intensity from 2 sources: (1) local area prereform uninsured rates from 2013 and (2) state participation in the Medicaid expansion. Including the third postreform year leads to 2 important insights. First, gains in health insurance coverage and access to care from the policy continued to increase in the third year. Second, an improvement in the probability of reporting excellent health emerged in the third year, with …

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.

Comparison Of Multiple Imputation Methods For Categorical Survey Items With High Missing Rates: Application To The Family Life, Activity, Sun, Health And Eating (Flashe) Study, Benmei Liu, Erin Hennessy, April Oh, Laura A. Dwyer, Linda Nebeling

Journal of Modern Applied Statistical Methods

Two multiple imputation methods, the Sequential Regression Multivariate Imputation Algorithm and the Cox-Lannacchione Weighted Sequential Hotdeck, were examined and compared to impute highly missing categorical variables from the Family Life, Activity, Sun, Health and Eating (FLASHE) study. This paper describes the imputation approaches and results from the study.

Dealing With Sensitive Quantitative Variables: A Comparison Of Sampling Designs For The Procedure Of Gupta And Thornton, Carlos Narciso Bouza Herrera, Prayas Sharma

Journal of Modern Applied Statistical Methods

The use of randomized response procedures allows diminishing the number of non-responses and increasing the accuracy of the responses. A new sampling strategy is developed where the reports are scrambled using the procedure of Gupta and Thornton. The estimator of the mean as well as the errors are developed for the Rao-Hartley-Cochran and Ranked Sets Sampling designs. The proposals are compared with the original model based on the use of simple random sampling.

Bayesian And Semi-Bayesian Estimation Of The Parameters Of Generalized Inverse Weibull Distribution, Kamaljit Kaur, Kalpana K. Mahajan, Sangeeta Arora

Journal of Modern Applied Statistical Methods

Bayesian and semi-Bayesian estimators of parameters of the generalized inverse Weibull distribution are obtained using Jeffreys’ prior and informative prior under specific assumptions of loss function. Using simulation, the relative efficiency of the proposed estimators is obtained under different set-ups. A real life example is also given.

A Further Extension Of The Extended Riemann-Liouville Fractional Derivative Operator, Martin Bohner, Gauhar Rahman, Shahid Mubeen, Kottakkaran Sooppy Nisar

Mathematics and Statistics Faculty Research & Creative Works

The main objective of this paper is to establish the extension of an extended fractional derivative operator by using an extended beta function recently defined by Parmar et al. by considering the Bessel functions in its kernel. We also give some results related to the newly defined fractional operator, such as Mellin transform and relations to extended hypergeometric and Appell's function via generating functions.

Effectiveness Of 4-Aminopyridine For The Management Of Spasticity In Spinal Cord Injury: A Systematic Review, Joshua Weiner, Jane Hsieh, Amanda Mcintyre, Robert Teasell

Epidemiology and Biostatistics Publications

Background: Spasticity is a common secondary complication of spinal cord injury (SCI), which can severely impact functional independence and quality of life. 4-Aminopyridine (4-AP) is a potassium channel blocker that has been studied as an intervention for spasticity in individuals with SCI. Objective: To conduct a systematic review of the available evidence regarding the effectiveness of 4-AP for the management of spasticity in individuals with SCI. Methods: A comprehensive literature search was conducted on five electronic databases for articles published in English up to January 2017. Studies were included if (1) the sample size was three or more subjects, (2) …

Semicontinuity Of Betweenness Functions, Paul Bankston, Aisling Mccluskey, Richard J. Smith

Mathematics, Statistics and Computer Science Faculty Research and Publications

A ternary relational structure〈X,[⋅,⋅,⋅]〉, interpreting a notion of betweenness, gives rise to the family of intervals, with interval [a,b] being defined as the set of elements of X between a and b. Under very reasonable circumstances, X is also equipped with some topological structure, in such a way that each interval is a closed nonempty subset of X. The question then arises as to the continuity behavior—within the hyperspace context—of the betweenness function {x,y}↦[x,y]. We investigate two broad scenarios: the first involves metric spaces and Menger's betweenness interpretation; the second deals with continua and the subcontinuum interpretation.

P-Value Histograms: Inference And Diagnostics, Patrick Breheny, Arnold Stromberg, Joshua Lambert

Statistics Faculty Publications

It is increasingly common for experiments in biology and medicine to involve large numbers of hypothesis tests. A natural graphical method for visualizing these tests is to construct a histogram from the p-values of these tests. In this article, we examine the shapes, both regular and irregular, that these histograms can take on, as well as present simple inferential procedures that help to interpret the shapes in terms of diagnosing potential problems with the experiment. We examine potential causes of these problems in detail, and discuss potential remedies. Throughout, examples of irregular-looking p-value histograms are provided and based …

Factors Influencing Immunisation Schedule Adherence And Completion At The Regional Level In The Philippines, Paolo Miguel Manalang Vicerra

Kesmas

Penyebab utama kematian bayi sebagian besar dapat dicegah dan terdapat alasan baik dari sisi suplai maupun permintaan layanan kesehatan hal itu dapat terus berlangsung. Penelitian ini bertujuan memastikan faktor-faktor yang memengaruhi perilaku layanan kesehatan preventif imunisasi bayi di Filipina yang tepat waktu karena tingkat kelengkapan, atau kepatuhan, telah stabil dalam beberapa dekade terakhir. Metode yang digunakan adalah pembuatan model statistik di tingkat subnasional. Sampel berisi bayi yang lahir sebelum Survei Demografi dan Kesehatan Nasional Filipina tahun 2013 untuk menentukan kepatuhan yang tepat terhadap jadwal imunisasi yang dimandatkan oleh pemerintah. Hal ini melibatkan penggabungan 17 wilayah administratif negara ke tiga wilayah …