Statistics and Probability Commons^™

Analysis Of Schizophrenia Data Using A Nonlinear Threshold Index Logistic Model., Zhenyu Jiang, Chengan Du, Assen Jablensky, Hua Liang, Zudi Lu, Yang Ma, Kok Lay Teo

GW Biostatistics Center

Genetic information, such as single nucleotide polymorphism (SNP) data, has been widely recognized as useful in prediction of disease risk. However, how to model the genetic data that is often categorical in disease class prediction is complex and challenging. In this paper, we propose a novel class of nonlinear threshold index logistic models to deal with the complex, nonlinear effects of categorical/discrete SNP covariates for Schizophrenia class prediction. A maximum likelihood methodology is suggested to estimate the unknown parameters in the models. Simulation studies demonstrate that the proposed methodology works viably well for moderate-size samples. The suggested approach is therefore …

Mediation Analysis Of Gestational Age, Congenital Heart Defects, And Infant Birth-Weight, Adane Wogu, Christopher Loffredo, Ionut Bebu, George Luta

GW Biostatistics Center

Background

In this study we assessed the mediation role of the gestational age on the effect of the infant’s congenital heart defects (CHD) on birth-weight.

Methods

We used secondary data from the Baltimore-Washington Infant Study (1981–1989). Mediation analysis was employed to investigate whether gestational age acted as a mediator of the association between CHD and reduced birth-weight. We estimated the mediated effect, the mediation proportion, and their corresponding 95% confidence intervals (CI) using several methods.

Results

There were 3362 CHD cases and 3564 controls in the dataset with mean birth-weight of 3071 (SD = 729) and 3353 (SD = 603) …

Engagement With Care, Substance Use, And Adherence To Therapy In Hiv/Aids, Patrice K. Nicholas, Suzanne Willard, Clinton J. Thompson, Carol Dawson-Rose, Inge B. Corless, +20 Additional Authors

GW Biostatistics Center

Engagement with care for those living with HIV is aimed at establishing a strong relationship between patients and their health care provider and is often associated with greater adherence to therapy and treatment (Flickinger, Saha, Moore, and Beach, 2013). Substance use behaviors are linked with lower rates of engagement with care and medication adherence (Horvath, Carrico, Simoni, Boyer, Amico, and Petroli, 2013). This study is a secondary data analysis using a cross-sectional design from a larger randomized controlled trial (n = 775) that investigated the efficacy of a self-care symptom management manual for participants living with HIV. Participants were …

Short And Long-Term Lifestyle Coaching Approaches Used To Address Diverse Participant Barriers To Weight Loss And Physical Activity Adherence, Elizabeth M. Venditti, Judith Wylie-Rosett, Linda M. Delahanty, Lisa L. Mele, Mary A. Hoskin, Sharon Edelstein

GW Biostatistics Center

Background

Individual barriers to weight loss and physical activity goals in the Diabetes Prevention Program, a randomized trial with 3.2 years average treatment duration, have not been previously reported. Evaluating barriers and the lifestyle coaching approaches used to improve adherence in a large, diverse participant cohort can inform dissemination efforts.

Methods

Lifestyle coaches documented barriers and approaches after each session (mean session attendance = 50.3 +/- 21.8). Subjects were 1076 intensive lifestyle participants (mean age = 50.6 years; mean BMI = 33.9 kg/m2; 68% female, 48% non-Caucasian). Barriers and approaches used to improve adherence were ranked by the percentage of …

Cardiometabolic Risk Assessments By Body Mass Index Z-Score Or Waist-To-Height Ratio In A Multiethnic Sample Of Sixth-Graders, Henry S. Kahn, Laure El Ghormli, Russell Jago, Gary D. Foster, Robert G. Mcmurray, John B. Buse, Diane D. Stadler, Roberto P. Trevino, Tom Baranowski, Healthy Study Group

GW Biostatistics Center

Convention defines pediatric adiposity by the body mass index -score (BMIz) referenced to normative growth charts. Waist-to-height ratio (WHtR) does not depend on sex-and-age references. In the HEALTHY Study enrollment sample, we compared BMIz with WHtR for ability to identify adverse cardiometabolic risk. Among 5,482 sixth-grade students from 42 middle schools, we estimated explanatory variations (R²) and standardized beta coefficients of BMIz or WHtR for cardiometabolic risk factors: insulin resistance (HOMA-IR), lipids, blood pressures, and glucose. For each risk outcome variable, we prepared adjusted regression models for four subpopulations stratified by sex and high versus lower fatness. …

Community Colleges And Public Health: An Integral Part Of The Continuum Of Education For Public Health, Richard Riegelman, Cynthia Wilson

Epidemiology Faculty Publications

No abstract provided.

Hiv Testing Implementation In Two Urban Cities: Practice, Policy, And Perceived Barriers., Camden J Hallmark, Jennifer Skillicorn, Thomas P Giordano, Jessica A Davila, Marlene Mcneese, Nestor Rocha, Avemaria Smith, Stacey Cooper, Amanda D. Castel

Epidemiology Faculty Publications

BACKGROUND: Although funding has supported the scale up of routine, opt-out HIV testing in the US, variance in implementation mechanisms and barriers in high-burden jurisdictions remains unknown.

METHODS: We conducted a survey of health care organizations in Washington, DC and Houston/Harris County to determine number of HIV tests completed in 2011, policy and practices associated with HIV testing, funding mechanisms, and reported barriers to testing in each jurisdiction and to compare results between jurisdictions.

RESULTS: In 2012, 43 Houston and 35 DC HIV-testing organizations participated in the survey. Participants represented 85% of Department of Health-supported testers in DC and 90% …

Primary Care-Based Educational Interventions To Decrease Risk Factors For Metabolic Syndrome For Adults With Major Psychotic And/Or Affective Disorders: A Systematic Review, Cynthia Nover, Sarah S. Jackson

Epidemiology Faculty Publications

Background

Individuals with major psychotic and/or affective disorders are at increased risk for developing metabolic syndrome due to lifestyle- and treatment-related factors. Numerous pharmacological and non-pharmacological interventions have been tested in inpatient and outpatient mental health settings to decrease these risk factors. This review focuses on primary care-based non-pharmacological (educational or behavioral) interventions to decrease metabolic syndrome risk factors in adults with major psychotic and/or affective disorders.

Methods

The authors conducted database searches of PsychINFO, MEDLINE and the Cochrane Database of Systematic Reviews, as well as manual searches and gray literature searches to identify included studies.

Results

The authors were …

Multiple Hypotheses Testing Procedures In Clinical Trials And Genomic Studies, Qing Pan

Epidemiology Faculty Publications

We review and compare multiple hypothesis testing procedures used in clinical trials and those in genomic studies. Clinical trials often employ global tests, which draw an overall conclusion for all the hypotheses, such as SUM test, Two-Step test, Approximate Likelihood Ratio test (ALRT), Intersection-Union Test (IUT), and MAX test. The SUM and Two-Step tests are most powerful under homogeneous treatment effects, while the ALRT and MAX test are robust in cases with non-homogeneous treatment effects. Furthermore, the ALRT is robust to unequal sample sizes in testing different hypotheses. In genomic studies, stepwise procedures are used to draw marker-specific conclusions and …

Targeting Inflammation Using Salsalate In Patients With Type 2 Diabetes: Effects On Flow-Mediated Dilation (Tinsal-Fmd)., Allison B Goldfine, J Stewart Buck, Cyrus Desouza, Vivian Fonseca, Yii-Der Ida Chen, Steven E Shoelson, Kathleen A. Jablonski, Mark A Creager, The Tinsal-Fmd Team

GW Biostatistics Center

OBJECTIVE: To test whether inhibiting inflammation with salsalate improves endothelial function in patients with type 2 diabetes (T2D).

RESEARCH DESIGN AND METHODS: We conducted an ancillary study to the National Institutes of Health-sponsored, multicenter, randomized, double-masked, placebo-controlled trial evaluating the safety and efficacy of salsalate in targeting inflammation to improve glycemia in patients with T2D. Flow-mediated, endothelium-dependent dilation (FMD) and endothelium-independent, nitroglycerin-mediated dilation (NMD) of the brachial artery were assessed at baseline and 3 and 6 months following randomization to either salsalate 3.5 g/day or placebo. The primary end point was change in FMD at 6 months.

RESULTS: A total …

Molecular Detection Of Culture-Confirmed Bacterial Bloodstream Infections With Limited Enrichment Time, Miranda S. Moore, Chase D. Mccann, Jeanne Jordan

Epidemiology Faculty Publications

Conventional blood culturing using automated instrumentation with phenotypic identification requires a significant amount of time to generate results. This study investigated the speed and accuracy of results generated using PCR and pyrosequencing compared to the time required to obtain Gram stain results and final culture identification for cases of culture-confirmed bloodstream infections. Research and physician-ordered blood cultures were drawn concurrently. Aliquots of the incubating research blood culture fluid were removed hourly between 5 and 8 h, at 24 h, and again at 5 days. DNA was extracted from these 6 time point aliquots and analyzed by PCR and pyrosequencing for …

Plasma S-Adenosylmethionine, Dnmt Polymorphisms, And Peripheral Blood Line-1 Methylation Among Healthy Chinese Adults In Singapore, Maki Inoue-Choi, Heather H. Nelson, Kim Robien, Erland Arning, Teodoro Bottiglieri, Woon-Puay Koh, Jian-Min Yuan

Epidemiology Faculty Publications

Background

Global hypomethylation of repetitive DNA sequences is believed to occur early in tumorigenesis. There is a great interest in identifying factors that contribute to global DNA hypomethylation and associated cancer risk. We tested the hypothesis that plasma S-adenosylmethionine (SAM) level alone or in combination with genetic variation in DNA methyltransferases (DNMT1, DNMT3A andDNMT3B) was associated with global DNA methylation extent at long interspersed nucleotide element-1 (LINE-1) sequences.

Methods

Plasma SAM level and LINE-1 DNA methylation index were measured using stored blood samples collected from 440 healthy Singaporean Chinese adults during 1994-1999. Genetic polymorphisms of …

Correlates Of Hiv Acquisition In A Cohort Of Black Men Who Have Sex With Men In The United States: Hiv Prevention Trials Network (Hptn) 061, Beryl A. Koblin, Kenneth H. Mayer, Susan H. Eshleman, Lei Wang, Sharon B. Mannheimer, Carlos Del Rio, Steve Shoptaw, Manya Magnus, Susan Buchbinder, Leo Wilton, Ting-Yuan Liu, Vanessa Cummings, Estelle Piwowar-Manning, Sheldon D. Fields, Sam Griffith, Vanessa Elharrar, Darrell Wheeler

Epidemiology Faculty Publications

Background

Black men who have sex with men (MSM) in the United States (US) are affected by HIV at disproportionate rates compared to MSM of other race/ethnicities. Current HIV incidence estimates in this group are needed to appropriately target prevention efforts.

Methods

From July 2009 to October 2010, Black MSM reporting unprotected anal intercourse with a man in the past six months were enrolled and followed for one year in six US cities for a feasibility study of a multi-component intervention to reduce HIV infection. HIV incidence based on HIV seroconversion was calculated as number of events/100 person-years. Multivariate proportional …

Cardiovascular Outcome Trials In Type 2 Diabetes And The Sulphonylurea Controversy: Rationale For The Active-Comparator Carolina Trial, Julio Rosenstock, Nikolaus Marx, Steven E. Kahn, Bernard Zinman, John J. Kastelein, John M. Lachin, Erich Bluhmki, Sanjay Patel, Odd-Erik Johansen, Hans-Jurgen Woerle

Epidemiology Faculty Publications

Sulphonylureas (SUs) are widely used glucose-lowering agents in type 2 diabetes mellitus (T2DM) with apparent declining efficacy over time. Concerns have been raised from observational retrospective studies on the cardiovascular (CV) safety of SUs but there are few long-term data on CV outcomes from randomized controlled trials (RCTs) involving the use of this class of agents. Most of the observational studies and registry data are conflicting and vary with study population and methodology used for analyses. To address the SU controversy, we reviewed the recently published literature (until end of the year 2011) to evaluate the impact of SUs on …

When To Start Antiretroviral Therapy: The Need For An Evidence Base During Early Hiv Infection, James D. Lundgren, Abdel G. Babiker, Fred M. Gordin, Alvaro H. Borges, James D. Neaton

Epidemiology Faculty Publications

Background

Strategies for use of antiretroviral therapy (ART) have traditionally focused on providing treatment to persons who stand to benefit immediately from initiating the therapy. There is global consensus that any HIV+ person with CD4 counts less than 350 cells/μl should initiate ART. However, it remains controversial whether ART is indicated in asymptomatic HIV-infected persons with CD4 counts above 350 cells/μl, or whether it is more advisable to defer initiation until the CD4 count has dropped to 350 cells/μl. The question of when the best time is to initiate ART during early HIV infection has always been vigorously debated. The …

Linking And Retaining Hiv Patients In Care: The Importance Of Provider Attitudes And Behaviors, Manya Magnus, Jane Herwehe, Michelli Murtaza-Rossini, Petera Reine, Damien Cuffie, Deann Gruber, Michael Kaiser

Epidemiology Faculty Publications

Retention in HIV treatment may reduce morbidity and mortality, as well as slow the epidemic. Myriad barriers to retention include stigma, homophobia, structural barriers, transportation, and insurance. The purpose of this study was to evaluate patient perceptions of provider attitudes among HIV-infected persons within a state-wide public hospital system in Louisiana. A convenience sample of patients attending HIV clinics throughout the state participated in an anonymous interview. Factors associated with negative perceptions of care were evaluated in conjunction with a validated stigma measure. Factors associated with having a delayed entry into or break in care were evaluated in conjunction with …

Progress Realized: Trends In Hiv-1 Viral Load And Cd4 Cell Count In A Tertiary-Care Center From 1999 Through 2011, Howard B. Gale, Manuel D. Rodriguez, Heather J. Hoffman, Debra A. Benator, Fred M. Gordin, Ann M. Labriola, Virginia L. Kan

Epidemiology Faculty Publications

Abstract

Accumulating evidence suggests that alterations in immune function may be important in the etiology of papillary thyroid cancer (PTC). To identify genetic markers in immune-related pathways, we evaluated 3,985 tag single nucleotide polymorphisms (SNPs) in 230 candidate gene regions (adhesion-extravasation-migration, arachidonic acid metabolism/eicosanoid signaling, complement and coagulation cascade, cytokine signaling, innate pathogen detection and antimicrobials, leukocyte signaling, TNF/NF-kB pathway or other) in a case-control study of 344 PTC cases and 452 controls. We used logistic regression models to estimate odds ratios (OR) and calculate one degree of freedom P values of linear trend (PSNP-trend) for the association …

Can Changes In Angiogenic Biomarkers Between The First And Second Trimesters Of Pregnancy Predict Development Of Pre-Eclampsia In A Low-Risk Nulliparous Patient Population?, Leslie Myatt, Rebecca G. Clifton, J. M. Roberts, Catherine Y. Spong, Ronald J. Wapner, +10 Additional Authors

GW Biostatistics Center

OBJECTIVE:

To determine if change in maternal angiogenic biomarkers between the first and second trimesters predicts pre-eclampsia in low-risk nulliparous women.

DESIGN:

A nested case-control study of change in maternal plasma soluble Flt-1 (sFlt-1), soluble endoglin (sEng) and placenta growth factor (PlGF). We studied 158 pregnancies complicated by pre-eclampsia and 468 normotensive nonproteinuric controls.

SETTING:

A multicentre study in 16 academic medical centres in the USA.

POPULATION:

Low-risk nulliparous women.

METHODS:

Luminex assays for PlGF, sFlt-1 and sEng performed on maternal EDTA plasma collected at 9-12, 15-18 and 23-26 weeks of gestation. Rate of change of analyte between first and …

Modeling The Impact And Costs Of Semiannual Mass Drug Administration For Accelerated Elimination Of Lymphatic Filariasis, Wilma A. Stolk, Quirine A. Ten Bosch, Sake J. De Vlas, Peter U. Fischer, Gary J. Weil, Ann S. Goldman

Epidemiology Faculty Publications

The Global Program to Eliminate Lymphatic Filariasis (LF) has a target date of 2020. This program is progressing well in many countries. However, progress has been slow in some countries, and others have not yet started their mass drug administration (MDA) programs. Acceleration is needed. We studied how increasing MDA frequency from once to twice per year would affect program duration and costs by using computer simulation modeling and cost projections. We used the LYMFASIM simulation model to estimate how many annual or semiannual MDA rounds would be required to eliminate LF for Indian and West African scenarios with varied …

Environmental Exposure To Pyrethroids And Sperm Sex Chromosome Disomy: A Cross-Sectional Study, Heather A. Young, John D. Meeker, Sheena E. Martenies, Zaida I. Figueroa, Dana Boyd Barr, Melissa J. Perry

Epidemiology Faculty Publications

Background

The role of environmental pesticide exposures, such as pyrethroids, and their relationship to sperm abnormalities are not well understood. This study investigated whether environmental exposure to pyrethroids was associated with altered frequency of sperm sex chromosome disomy in adult men.

Methods

A sample of 75 subjects recruited through a Massachusetts infertility clinic provided urine and semen samples. Individual exposures were measured as urinary concentrations of three pyrethroid metabolites ((3-phenoxybenzoic acid (3PBA), cis- and trans- 3-(2,2-Dichlorovinyl)-1-methylcyclopropane-1,2-dicarboxylic acid (CDCCA and TDCCA)). Multiprobe fluorescence in situ hybridization for chromosomes X, Y, and 18 was used to determine XX, YY, XY, 1818, and …

Information And Communication Technology To Link Criminal Justice Reentrants To Hiv Care In The Community, Ann Kurth, Irene Kuo, James Peterson, Nkiru Azikiwe, Lauri Bazerman, Alice Cates, Curt G. Beckwith

Epidemiology Faculty Publications

The United States has the world’s highest prison population, and an estimated one in seven HIV-positive persons in the USA passes through a correctional facility annually. Given this, it is critical to develop innovative and effective approaches to support HIV treatment and retention in care among HIV-positive individuals involved in the criminal justice (CJ) system. Information and communication technologies (ICTs), including mobile health (mHealth) interventions, may offer one component of a successful strategy for linkage/retention in care. We describe CARE+ Corrections, a randomized controlled trial (RCT) study now underway in Washington, that will evaluate the combined effect of computerized motivational …

Obesity And Preference-Weighted Quality Of Life Of Ethnically Diverse Middle School Children: The Healthy Study, Roberto P. Trevino, Trang H. Pham, Sharon Edelstein

GW Biostatistics Center

No abstract provided.

Transmission Potential Of Influenza A/H7n9, February To May 2013, China, Gerardo Chowell, Lone Simonsen, Sherry Towers, Mark A. Miller, Cecile G. Viboud

Epidemiology Faculty Publications

Background

On 31 March 2013, the first human infections with the novel influenza A/H7N9 virus were reported in Eastern China. The outbreak expanded rapidly in geographic scope and size, with a total of 132 laboratory-confirmed cases reported by 3 June 2013, in 10 Chinese provinces and Taiwan. The incidence of A/H7N9 cases has stalled in recent weeks, presumably as a consequence of live bird market closures in the most heavily affected areas. Here we compare the transmission potential of influenza A/H7N9 with that of other emerging pathogens and evaluate the impact of intervention measures in an effort to guide pandemic …

A Case–Control Study Of Incident Rheumatological Conditions Following Acute Gastroenteritis During Military Deployment, Kathryn Deyoung, Mark A. Riddle, Larissa S. May, Chad K. Porter

Epidemiology Faculty Publications

Objectives The aim of this study was to assess the risk of incident rheumatological diagnoses (RD) associated with self-reported diarrhoea and vomiting during a first-time deployment to Iraq or Afghanistan. Such an association would provide evidence that RD in this population may include individuals with reactive arthritis (ReA) from deployment-related infectious gastroenteritis.

Design This case–control epidemiological study used univariate and multivariate logistic regression to compare the odds of self-reported diarrhoea/vomiting among deployed US military personnel with incident RD to the odds of diarrhoea/vomiting among a control population.

Setting We analysed health records of personnel deployed to Iraq or Afghanistan, including …

Effects Of Genetic Variants Previously Associated With Fasting Glucose And Insulin In The Diabetes Prevention Program, Jose C. Florez, Kathleen A. Jablonski, Jarred B. Mcateer, Paul W. Franks, Clinton C. Mason, Kieren J. Mather, Edward Horton, Ronald Goldberg, Dana Dabelea, Steven E. Kahn, Richard F. Arakaki, Alan R. Shuldiner, William C. Knowler

Epidemiology Faculty Publications

Common genetic variants have been recently associated with fasting glucose and insulin levels in white populations. Whether these associations replicate in pre-diabetes is not known. We extended these findings to the Diabetes Prevention Program, a clinical trial in which participants at high risk for diabetes were randomized to placebo, lifestyle modification or metformin for diabetes prevention. We genotyped previously reported polymorphisms (or their proxies) in/near G6PC2, MTNR1B, GCK, DGKB, GCKR, ADCY5, MADD, CRY2, ADRA2A,FADS1, PROX1, SLC2A2, GLIS3, C2CD4B, IGF1, and IRS1 in 3,548 Diabetes …

Genetic Modulation Of Lipid Profiles Following Lifestyle Modification Or Metformin Treatment: The Diabetes Prevention Program, Toni I. Pollin, Tamara Isakova, Kathleen A. Jablonski, Paul I.W. De Bakker, Andrew Taylor, Jarred B. Mcateer, Qing Pan, Edward Horton, Linda M. Delahanty, David Altshuler, Alan R. Shuldiner, Ronald Goldberg, Jose C. Florez, George A. Bray

Epidemiology Faculty Publications

Weight-loss interventions generally improve lipid profiles and reduce cardiovascular disease risk, but effects are variable and may depend on genetic factors. We performed a genetic association analysis of data from 2,993 participants in the Diabetes Prevention Program to test the hypotheses that a genetic risk score (GRS) based on deleterious alleles at 32 lipid-associated single-nucleotide polymorphisms modifies the effects of lifestyle and/or metformin interventions on lipid levels and nuclear magnetic resonance (NMR) lipoprotein subfraction size and number. Twenty-three loci previously associated with fasting LDL-C, HDL-C, or triglycerides replicated (P = 0.04–1×10−17). Except for total HDL particles (r = −0.03, …

Fall In C-Peptide During First 2 Years From Diagnosis: Evidence Of At Least Two Distinct Phases From Composite Type 1 Diabetes Trialnet Data., Carla J. Greenbaum, Craig A. Beam, David Boulware, Stephen E. Gitelman, Peter A. Gottlieb, Kevan C. Herold, John M. Lachin, Paula L. Mcgee, Jerry P. Palmer, Mark D. Pescovitz, Heidi Krause-Steinrauf, Jay S. Skyler, Jay M. Sosenko

Epidemiology Faculty Publications

Interpretation of clinical trials to alter the decline in β-cell function after diagnosis of type 1 diabetes depends on a robust understanding of the natural history of disease. Combining data from the Type 1 Diabetes TrialNet studies, we describe the natural history of β-cell function from shortly after diagnosis through 2 years post study randomization, assess the degree of variability between patients, and investigate factors that may be related to C-peptide preservation or loss. We found that 93% of individuals have detectable C-peptide 2 years from diagnosis. In 11% of subjects, there was no significant fall from baseline by 2 …

Selective Impact Of Hiv Disease Progression On The Innate Immune System In The Human Female Reproductive Tract., Timothy Lahey, Mimi Ghosh, John V. Fahey, Zheng Sheng, Lucy R. Mukura, Yan Song, Susan Cu-Uvin, Kenneth H. Mayer, Peter F. Wright, John C. Kappes, Christina Ochsenbauer, Charles R. Wira

Epidemiology Faculty Publications

Background

We have previously demonstrated intrinsic anti-HIV activity in cervicovaginal lavage (CVL) from HIV-infected women with high CD4 counts and not on antiretroviral therapy. However, the impact of HIV disease progression on CVL innate immune responses has not been delineated.

Methods

CVL from 57 HIV-infected women not on antiretroviral therapy were collected by washing the cervicovaginal area with 10 ml of sterile normal saline. We characterized subject HIV disease progression by CD4 count strata: >500 cells/µl, 200–500 cells/µl, or <200 cells/µl of blood. To assess CVL anti-HIV activity, we incubated TZM-bl cells with HIV plus or minus CVL. Antimicrobials, cytokines, chemokines and anti-gp160 HIV IgG antibodies were measured by ELISA and Luminex.

Results

CVL exhibited broad anti-HIV activity against multiple laboratory-adapted and transmitted/founder (T/F) viruses, with anti-HIV activity ranging from 0 to 100% …

Change-Point Analysis Of Paired Allele-Specific Copy Number Variation Data, Yinglei Lai

GW Biostatistics Center

The recent genome-wide allele-specific copy number variation data enable us to explore two types of genomic information including chromosomal genotype variations as well as DNA copy number variations. For a cancer study, it is common to collect data for paired normal and tumor samples. Then, two types of paired data can be obtained to study a disease subject. However, there is a lack of methods for a simultaneous analysis of these four sequences of data. In this study, we propose a statistical framework based on the change-point analysis approach. The validity and usefulness of our proposed statistical framework are demonstrated …

Characteristics Of Children With Type 1 Diabetes And Persistent Suboptimal Glycemic Control., Hyuntae Kim, Angelo Elmi, Celia L. Henderson, Fran R. Cogen, Paul B. Kaplowitz

Epidemiology Faculty Publications

Objective: This study aims to determine the relationship between the duration of persistent poor glycemic control in type 1 diabetes mellitus (T1DM) children and the likelihood of subsequent improvement.

Methods: A retrospective cohort study was conducted on T1DM patients aged 6-18 years, followed for at least six visits at Children’s National Medical Center (Washington, DC) with at least one hemoglobin A1c (HbA1c) ≥10% after the first year since the initial visit (n=151). Medical records of patients with subsequently improved glycemic control were reviewed (n=39).

Results: Patients aged 12-18 years, females, and Medicaid patients were twice as likely to be in …