Epidemiology Commons^™

Characterization Of Plasmodium Falciparum And Plasmodium Vivax Recent Exposure In An Area Of Significantly Decreased Transmission Intensity In Central Vietnam, Johanna Helena Kattenberg, Annette Erhart, Minh Hieu Truong, Eduard Rovira-Vallbona, Khac Anh Dung Vu, Thi Hong Ngoc Nguyen, Van Hong Nguyen, Van Van Nguyen, Melanie Bannister-Tyrrell, Michael Theisen, Adam Bennet, Andrew A. Lover, Thanh Duong Tran, Xuan Xa Nguyen, Anna Rosanas-Urgell

Andrew Lover

Malaria Elimination: Time To Target All Species, Andrew A. Lover, J. Kevin Baird, Roly Gosling, Ric N. Price

Andrew Lover

Vitamin D Status And Demographic And Lifestyle Determinants Among Adults In The United States (Nhanes 2001-2006), Yan Cao, Katie L. Callahan, Sreenivas P. Veeranki, Yang Chen, Ying Liu, Shimin Zheng

Shimin Zheng

This study looked at risk factors associated with vitamin D levels in the body among a representative sample of adults in the U.S., NHANES III (2001-2006) data were used to assess the relationship between several demographic and health risk factors and vitamin D levels in the body. The Baseline-Category Logit Model was used to test the association between vitamin D level and the potential risk factors age, education, ethnicity, poverty status, physical activity, smoking, alcohol, obesity, diabetes and total cholesterol with both genders. Vitamin D insufficiency and deficiency were significantly associated with age, race, education, physical activity, obesity, diabetes and …

The Use Of Vital Statistics Data For Research Of Consequence: Birth Outcomes And Population Health In A Rural Region, Claudia Kozinetz, Shimin Zheng, Eunice Mogusu

Shimin Zheng

Objective: The Affordable Care Act (ACA) has influenced increasing interests in population health and population health outcomes. The purpose of this study was to exemplify the importance of using existing vital statistics data for understanding and monitoring health outcomes and consequentially health disparities at the population level. Data from birth records for two geographic regions from 2009-2014 were compared; low birth weight (LBW) and preterm delivery (PD) were used as surrogates for population health outcomes. Methods: A population-based, multi-year, cross-sectional study design using a pooled dataset of birth records from Tennessee (TN) was the framework for the analyses. A sub-population …

Trends And Determinants Of Up-To-Date Status With Colorectal Cancer Screening In Tennessee, 2002-2008, Sreenivas P. Veeranki, Shimin Zheng

Shimin Zheng

BACKGROUND: Screening rates for colorectal cancer (CRC) are increasing nationwide including Tennessee (TN); however, their up-to-date status is unknown. The objective of this study is to determine the trends and characteristics of TN adults who are up-to-date status with CRC screening during 2002-2008. METHODS: We examined data from the TN Behavioral Risk Factor Surveillance System for 2002, 2004, 2006 and 2008 to estimate the proportion of respondents aged 50 years and above who were up-to-date status with CRC screening, defined as an annual home fecal occult blood test and/or sigmoidoscopy or colonoscopy in the past 5 years. We identified trends …

The Association Of Calcium Intake And Other Risk Factors With Cardiovascular Disease Among Obese Adults In Usa, Yang Chen, Sheryl Strasser, Katie Callahan, David Blackley, Yan Cao, Liang Wang, Shimin Zheng

Shimin Zheng

In this study, we used a cross-sectional study design to examine the relationship between the calcium intake and risk factors for CVD among obese adults by using continuous waves of National Health and Nutrition Examination Survey (NHANES) data 1999-2010. The association between calcium intake and risk factors of CVD (hypertension, total cholesterol, HDL, glycohemoglobin), CRP, albuminuria) is assessed among obese adults in USA. The incidence of Cardiovascular Disease (CVD) is high among obese people. The potential effects of inadequate calcium intake on CVD are receiving increased epidemiologic attention. Understanding the association between risk factors for CVD and calcium intake among …

Associations Of Smoking Status And Serious Psychological Distress With Chronic Obstructive Pulmonary Disease, Ke-Sheng Wang, Liang Wang, Shimin Zheng, Long-Yang Wu

Shimin Zheng

Background: Chronic obstructive pulmonary disease (COPD) has been a major public health problem due to its high prevalence, morbidity, and mortality. Smoking is a major risk factor for COPD, while serious psychological distress (SPD) is prevalent among COPD patients. However, no study focusing on the effect of SPD on COPD has been so far conducted, while few studies have focused on the associations of SPD and behavioral factors with COPD by smoking status. Objectives: This study aimed to examine the associations of SPD and behavioral factors (such as smoking and physical activity) with COPD. Materials and Methods: Weighted logistic regression …

Evaluation Of Progress Towards The Unaids 90-90-90 Hiv Care Cascade: A Description Of Statistical Methods Used In An Interim Analysis Of The Intervention Communities In The Search Study, Laura Balzer, Joshua Schwab, Mark J. Van Der Laan, Maya L. Petersen

Laura B. Balzer

WHO guidelines call for universal antiretroviral treatment, and UNAIDS has set a global target to virally suppress most HIV-positive individuals. Accurate estimates of population-level coverage at each step of the HIV care cascade (testing, treatment, and viral suppression) are needed to assess the effectiveness of "test and treat" strategies implemented to achieve this goal. The data available to inform such estimates, however, are susceptible to informative missingness: the number of HIV-positive individuals in a population is unknown; individuals tested for HIV may not be representative of those whom a testing intervention fails to reach, and HIV-positive individuals with a viral …

Regional Initiatives For Malaria Elimination: Building And Maintaining Partnerships, Andrew A. Lover, Kelly E. Harvard, Alistair E. Lindawson, Cara Smith Gueye, Rima Shretta, Roly Gosling, Richard Feachem

Andrew Lover

• Country programs and international donors are increasingly focused on regional approaches to malaria elimination; regional initiatives have been established in southern Africa, the Arabian Peninsula, Asia Pacific, Eastern Europe, and Latin America. Despite this growing attention, there is limited information and guidance on both key activities and organizational components of regional initiatives.
• In a review conducted for this policy forum, common characteristics across existing regional initiatives emerged: building a region-specific evidence base, leveraging expertise and resources, shifting commodities or pooling procurement, developing data-sharing systems, mobilizing resources, promoting high-level accountability, and strengthening advocacy.
• Regional initiatives share key structural elements: a strategic …

Malaria Risk Factors And Care-Seeking Behaviour Within The Private Sector Among High-Risk Populations In Vietnam: A Qualitative Study, Ingrid Chen, Huong Ngo Thi Thanh, Andrew A. Lover, Phung Thi Thao, Tang Viet Luu, Hoang Nghia Thang, Ngo Duc Thang, Josselyn Neukom, Adam Bennett

Andrew Lover

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

Leo Wilton

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 …

Introduction To Targeted Learning, Laura Balzer

Laura B. Balzer

No abstract provided.

Early Diagnosis Of Dengue Disease Severity In A Resource-Limited Asian Country, Philippe Cavailler, Arnaud Tarantola, Yee Sin Leo, Andrew A. Lover, Anne Rachline, Duch Moniboth, Rekol Huy, Ai Li Quake, Kdan Yuvatha, Veasna Duong, Jeremy L. Brett, Philippe Buchy

Andrew Lover

Serological Evidence For Localized And Persistent Antibody Response In Zika Virus-Positive Neonates With Microcephaly (Brazil, 2015)- A Secondary Analysis, Andrew A. Lover

Andrew Lover

Effects Of Cost Sharing On Seeking Care For Serious And Minor Symptoms. Results Of A Randomized Controlled Trial, Martin Shapiro, John Ware, Cathy Sherbourne

Martin Shapiro

To estimate the effect of cost sharing on seeking care for serious and minor symptoms, we analyzed data for 3539 persons aged 17 to 61 from the Rand Health Insurance Experiment. Participants were randomly assigned to a free-care group or to insurance plans requiring them to pay part of the costs (cost-sharing group). Annual surveys were administered to determine if participants had serious and minor symptoms during the preceding month and whether they saw a physician. Serious symptoms were judged by a panel of physicians to warrant care in most instances; minor symptoms were judged neither to be severe nor …

Neoadjuvant Or Adjuvant Therapy For Resectable Esophageal Cancer: A Systematic Review And Meta-Analysis, Richard Malthaner, Rebecca Wong, R. Rumble, Lisa Zuraw

Richard A. Malthaner

Background: Carcinoma of the esophagus is an aggressive malignancy with an increasing incidence. Its virulence, in terms of symptoms and mortality, justifies a continued search for optimal therapy. The large and growing number of patients affected, the high mortality rates, the worldwide geographic variation in practice, and the large body of good quality research warrants a systematic review with meta-analysis.

Methods: A systematic review and meta-analysis investigating the impact of neoadjuvant or adjuvant therapy on resectable thoracic esophageal cancer to inform evidence-based practice was produced.MEDLINE, CANCERLIT, Cochrane Library, EMBASE, and abstracts from the American Society of Clinical Oncology and the …

Neoadjuvant Or Adjuvant Therapy For Resectable Esophageal Cancer: A Clinical Practice Guideline, Richard Malthaner, Rebecca Wong, R. Rumble, Lisa Zuraw

Richard A. Malthaner

Background: Carcinoma of the esophagus is an aggressive malignancy with an increasing incidence. Its virulence, in terms of symptoms and mortality, justifies a continued search for optimal therapy. A clinical practice guideline was developed based on a systematic review investigating neoadjuvant or adjuvant therapy on resectable thoracic esophageal cancer. Methods: A systematic review with meta-analysis was developed and clinical recommendations were drafted. External review of the practice guideline report by practitioners in Ontario, Canada was obtained through a mailed survey, and incorporated. Final approval of the practice guideline was obtained from the Practice Guidelines Coordinating Committee. Results: The systematic review …

Cyclosporin Versus Tacrolimus For Liver Transplanted Patients, Elizabeth Haddad, Vivian Mcalister, Elizabeth Renouf, Richard Malthaner, Mette Kjaer, Lise Gluud

Richard A. Malthaner

A systematic review of randomized clinical trials (RCT) was undertaken to evaluate the beneficial and harmful effects of immunosuppression with cyclosporin versus tacrolimus for liver transplanted patients. MEDLINE, EMBASE, Cochrane Central and Hepato-Biliary Group Controlled Trials Registers were searched. Using fixed and random effects model, relative risk (RR), values <1 favoring>tacrolimus, with 95% confidence intervals (CI) were calculated. Of 717 potentially relevant references, 16 RCTs were eligible for inclusion. Mortality and graft loss at 1 year were significantly reduced in tacrolimus-treated recipients (Death: RR 0.85, 95% CI 0.73-0.99; graft loss: RR 0.73, 95% CI 0.61-0.86). Tacrolimus reduced the number of recipients …

Neoadjuvant Or Adjuvant Therapy For Resectable Esophageal Cancer: A Systematic Review And Meta-Analysis, Richard Malthaner, Rebecca Wong, R. Rumble, Lisa Zuraw

Richard A. Malthaner

Background: Carcinoma of the esophagus is an aggressive malignancy with an increasing incidence. Its virulence, in terms of symptoms and mortality, justifies a continued search for optimal therapy. The large and growing number of patients affected, the high mortality rates, the worldwide geographic variation in practice, and the large body of good quality research warrants a systematic review with meta-analysis.

Methods: A systematic review and meta-analysis investigating the impact of neoadjuvant or adjuvant therapy on resectable thoracic esophageal cancer to inform evidence-based practice was produced.MEDLINE, CANCERLIT, Cochrane Library, EMBASE, and abstracts from the American Society of Clinical Oncology and the …

Neoadjuvant Or Adjuvant Therapy For Resectable Esophageal Cancer: A Clinical Practice Guideline, Richard Malthaner, Rebecca Wong, R. Rumble, Lisa Zuraw

Richard A. Malthaner

Background: Carcinoma of the esophagus is an aggressive malignancy with an increasing incidence. Its virulence, in terms of symptoms and mortality, justifies a continued search for optimal therapy. A clinical practice guideline was developed based on a systematic review investigating neoadjuvant or adjuvant therapy on resectable thoracic esophageal cancer.

Methods: A systematic review with meta-analysis was developed and clinical recommendations were drafted. External review of the practice guideline report by practitioners in Ontario, Canada was obtained through a mailed survey, and incorporated. Final approval of the practice guideline was obtained from the Practice Guidelines Coordinating Committee.

Results: The systematic review …

Cyclosporin Versus Tacrolimus For Liver Transplanted Patients, Elizabeth Haddad, Vivian Mcalister, Elizabeth Renouf, Richard Malthaner, Mette Kjaer, Lise Gluud

Richard A. Malthaner

A systematic review of randomized clinical trials (RCT) was undertaken to evaluate the beneficial and harmful effects of immunosuppression with cyclosporin versus tacrolimus for liver transplanted patients. MEDLINE, EMBASE, Cochrane Central and Hepato-Biliary Group Controlled Trials Registers were searched. Using fixed and random effects model, relative risk (RR), values <1 favoring>tacrolimus, with 95% confidence intervals (CI) were calculated. Of 717 potentially relevant references, 16 RCTs were eligible for inclusion. Mortality and graft loss at 1 year were significantly reduced in tacrolimus-treated recipients (Death: RR 0.85, 95% CI 0.73-0.99; graft loss: RR 0.73, 95% CI 0.61-0.86). Tacrolimus reduced the number of recipients …

Leukoaraiosis Predicts Poor 90-Day Outcome After Acute Large Cerebral Artery Occlusion, Nils Henninger, Eugene Lin, Stephen Baker, Ajay Wakhloo, Deepak Takhtani, Majaz Moonis

Nils Henninger

BACKGROUND: To date limited information regarding outcome-modifying factors in patients with acute intracranial large artery occlusion (ILAO) in the anterior circulation is available. Leukoaraiosis (LA) is a common finding among patients with ischemic stroke and has been associated with poor post-stroke outcomes but its association with ILAO remains poorly characterized. This study sought to clarify the contribution of baseline LA and other common risk factors to 90-day outcome (modified Rankin Scale, mRS) after stroke due to acute anterior circulation ILAO. METHODS: We retrospectively analyzed 1,153 consecutive patients with imaging-confirmed ischemic stroke during a 4-year period (2007-2010) at a single academic …

Case Studies In Evaluating Time Series Prediction Models Using The Relative Mean Absolute Error, Nicholas G. Reich, Justin Lessler, Krzysztof Sakrejda, Stephen A. Lauer, Sopon Iamsirithaworn, Derek A T Cummings

Nicholas G Reich

Statistical prediction models inform decision-making processes in many real-world settings. Prior to using predictions in practice, one must rigorously test and validate candidate models to ensure that the proposed predictions have sufficient accuracy to be used in practice. In this paper, we present a framework for evaluating time series predictions that emphasizes computational simplicity and an intuitive interpretation using the relative mean absolute error metric. For a single time series, this metric enables comparisons of candidate model predictions against naive reference models, a method that can provide useful and standardized performance benchmarks. Additionally, in applications with multiple time series, this …

Epidemiology Of Latency And Relapse In Plasmodium Vivax Malaria, Andrew A. Lover

Andrew Lover

Considerations For Comprehensive Analyses Of Sporozoite-Based Controlled Human Malaria Infection Studies, Andrew A. Lover

Andrew Lover

Short Report: Study Variability In Recent Human Challenge Experiments With Plasmodium Falciparum Sporozoites (Pfspz Challenge), Andrew A. Lover

Andrew Lover

Trends In The Prevalence And Mortality Of Cognitive Impairment In The United States: Is There Evidence Of A Compression Of Cognitive Morbidity, Kenneth Langa, Eric Larson, Jason Karlawish, David Cutler, Mohammed Kabeto, Scott Kim, Allison Rosen

Jason Karlawish

BACKGROUND: Recent medical, demographic, and social trends might have had an important impact on the cognitive health of older adults. To assess the impact of these multiple trends, we compared the prevalence and 2-year mortality of cognitive impairment (CI) consistent with dementia in the United States in 1993 to 1995 and 2002 to 2004. METHODS: We used data from the Health and Retirement Study (HRS), a nationally representative population-based longitudinal survey of U.S. adults. Individuals aged 70 years or older from the 1993 (N = 7,406) and 2002 (N = 7,104) waves of the HRS were included. CI was determined …

Stochastic Variation In Network Epidemic Models: Implications For The Design Of Community Level Hiv Prevention Trials, David Boren, Patrick Sullivan, Chris Beyrer, Stefan Baral, Linda-Gail Becker, Ron Brookmeyer

Ron Brookmeyer

Important sources of variation in the spread of HIV in communities arise from overlapping sexual networks and heterogeneity in biological and behavioral risk factors in populations. These sources of variation are not routinely accounted for in the design of HIV prevention trials. In this paper, we use agent based models to account for these sources of variation. We illustrate the approach with an agent based model for the spread of HIV infection among men who have sex with men (MSM) in South Africa. We find that traditional sample size approaches that rely on binomial (or Poisson) models are inadequate and …

Cluster Randomized Trials And Statistical Power, Stephen A. Lauer, Nicholas G. Reich

Nicholas G Reich

The cluster-randomized trial (CRT) is a common study design in public health research. In situations where dividing a group of individuals into treatment and controls is unethical or impossible, a CRT design maintains the strengths of a randomized study design. By comparing the outcomes of small populations (clusters), we can observe the impacts of interventions on the community as a whole. Public health researchers around the world have utilized CRTs to measure the effect of, for example, de-worming medication on school attendance, financial incentives on doctor absenteeism, and providing chlorine to waterholes. The CRT can be a potent tool, however …

Depicting Estimates Using The Intercept In Meta-Regression Models: The Moving Constant Technique, Blair T. Johnson Dr., Tania B. Huedo-Medina Dr.

Blair T. Johnson

In any scientific discipline, the ability to portray research patterns graphically often aids greatly in interpreting a phenomenon. In part to depict phenomena, the statistics and capabilities of meta-analytic models have grown increasingly sophisticated. Accordingly, this article details how to move the constant in weighted meta-analysis regression models (viz. “meta-regression”) to illuminate the patterns in such models across a range of complexities. Although it is commonly ignored in practice, the constant (or intercept) in such models can be indispensible when it is not relegated to its usual static role. The moving constant technique makes possible estimates and confidence intervals at …