Epidemiology Commons^™

The Impact Of Coarsening The Explanatory Variable Of Interest In Making Causal Inferences: Implicit Assumptions Behind Dichotomizing Variables, Ori M. Stitelman, Alan E. Hubbard, Nicholas P. Jewell

U.C. Berkeley Division of Biostatistics Working Paper Series

It is common in analyses designed to estimate the causal effect of a continuous exposure/treatment to dichotomize the variable of interest. By dichotomizing the variable and assessing the causal effect of the newly fabricated variable practitioners are implicitly making assumptions. However, in most analyses these assumptions are ignored. In this article we formally address what assumptions are made in dichotomizing variables to assess causal effects. We introduce two assumptions, either of which must be met, in order for the estimates of the causal effects to be unbiased estimates of the parameters of interest. We title those assumptions the Mechanism Equivalence …

Hiv Risk Factors Among Moroccan And Turkish Same-Sex Attracted Youth In Amsterdam, Daniel Woznica

Independent Study Project (ISP) Collection

This report is the outcome of a month-long exploratory study on the main HIV risk factors among Moroccan and Turkish same-sex attracted (SSA) youth in Amsterdam. Data was obtained by way of interviews conducted with five experts, categorized as: academics, sexual and ethnic minority activists, and HIV professionals. Five main risk factors were determined: cultural differences; language barriers; stigma and taboo around sexuality and HIV within Islamic communities; socioeconomic marginalization; and lack of a positive term for same-sex sexual behavior and identity among the target group. Recommendations for future research include interviews with Moroccan and Turkish SSA youth themselves. Implications …

A Gis Analysis Of The Environmental Variables Related To Rift Valley Fever Outbreaks, Jacqueline Florette Jackson

Health Services Research Dissertations

Rift Valley fever is a mosquito-borne disease that causes widespread febrile illness and mortality in domestic animals as well as humans (Gaff, 2007). Rift Valley fever virus was first isolated in 1931 (Daubney, 1931), and since then, outbreaks have occurred in sub-Saharan Africa, southern Africa, Egypt, Saudi Arabia, Yemen and Madagascar, proving it to be a virus able to invade ecologically diverse regions (Gaff, 2007). The potential introduction of Rift Valley fever into the United States suggests the potential for human infection and major economic disruption. It is important to understand the role environmental variables have played in historical outbreaks …

Effects Of Leas And Mecury On The Blood Proteome Of Children, Robert E. Birsall, Michael P. Kiley, Zaneer M. Segu, Christopher D. Palmer, Milan Madera, Brooks B. Gump

Falk College Research Center

Heavy metal exposure in children has been associated with a variety of physiological and neurological problems. The goal of this study was to utilize proteomics to enhance the understanding of biochemical interactions responsible for the health problems related to lead and mercury exposure at concentrations well below CDC guidelines. Blood plasma and serum samples from 34 children were depleted of their most abundant proteins using antibody-based affinity columns and analyzed using two different methods, LC-MS/MS and 2-D electrophoresis coupled with MALDI-TOF/MS and tandem mass spectrometry. Apolipoprotein E demonstrated an inverse significant association with lead concentrations (average being one microgram/deciliter) as …

Identifikasi Penyebab Diare Di Kabupaten Karangasem, Bali, I N. Sujaya, N.P. Desy Aryantini, N.W. Nursini, S.G. Purnama, N.M.U. Dwipayanti, I G. Artawan, I M. Sutarga

Kesmas

Pada Februari hingga Maret 2008 terjadi kejadian luar biasa muntah berak (diare) di Kabupaten Karangasem Bali. Tercatat sekitar 600 orang mengalami muntaber dan 5 orang meninggal dunia. Ini merupakan kejadian KLB muntaber pertama kali di Bali serta belum diketahui patogen penyebab diare tersebut. Tujuan penelitian ini adalah mengidentifikasi penyebab diare di Karangasem serta kemungkinan rantai penularannya. Penelusuran penyebab KLB dilakukan dengan menganalisis sampel air yang diambil dari sumber air umum, cubang/sumur penduduk, bahan makanan, serta rectal swab penderita dengan kombinasi teknik pemupukan kuman dan PCR spesifik dengan target gen pembentuk toksin pada Escherichia coli. Dengan melakukan kultur pada sampel makanan …

Malaria And Helminth Co-Infections In Outpatients Of Alaba Kulito Health Center, Southern Ethiopia: A Cross Sectional Study, Abraham Degarege, Abebe Animut, Mengistu Legesse, Berhanu Erko

Journal Articles: Epidemiology

BACKGROUND: Distribution of malaria and intestinal helminths is known to overlap in developing tropical countries of the world. Co-infections with helminth and malaria parasites cause a significant and additive problem against the host. The aim of this study was to asses the prevalence of malaria/helminth co-infection and the associated problems among febrile outpatients that attended Alaba Kulito Health Center, southern Ethiopia November and December 2007. A total of 1802 acute febrile patients were diagnosed for malaria. 458 Giemsa-stained thick and thin blood films were used for identification of Plasmodium species and Stool samples prepared using Kato-Katz technique were used to …

Recent Diarrhea Is Associated With Elevated Salivary Igg Responses To Cryptosporidium In Residents Of An Eastern Massachusetts Community, A. I. Egorov, L. M. Montuori Trimble, L. Ascolillo, H. D. Ward, Deborah A. Levy, R. D. Morris, E. N. Naumova, J. K. Griffiths

Journal Articles: Epidemiology

BACKGROUND: Serological data suggest that Cryptosporidium infections are common but underreported. The invasiveness of blood sampling limits the application of serology in epidemiological surveillance. We pilot-tested a non-invasive salivary anti-Cryptosporidium antibody assay in a community survey involving children and adults.

MATERIALS AND METHODS: Families with children were recruited in a Massachusetts community in July; symptoms data were collected at 3 monthly follow-up mail surveys. One saliva sample per person (n = 349) was collected via mail, with the last survey in October. Samples were analyzed for IgG and IgA responses to a recombinant C. hominis gp15 sporozoite protein using a …

Risk Factors For Development Of High Blood Pressure And Obesity Among African American Adolescents, Monique Shanta White

Walden Dissertations and Doctoral Studies

Childhood obesity has reached epidemic proportions in the United States and has been linked to hypertension, especially among African American youth. Optimistic bias leads youth to underestimate their susceptibility to negative health outcomes. Public health officials want to reduce risk factors to result in significant long term reduction in cardiovascular disease. The purpose of this study was to explore adolescent behavior practices in a school district and prevalence of high blood pressure and obesity in that population. The health belief model guided the framework for this study. Research questions examined relationship between individual health risk practices and optimistic bias on …

Observer-Dependent Model For Analyzing Subjective Parameters In Epidemiology, Milad Zarei

Open Access Theses & Dissertations

Although medical technologies for preventing the contagion and spread of infectious diseases have improved steadily throughout the last century, new infectious diseases are still emerging and spreading swiftly. The modeling of infectious disease spread is crucial in addressing the lack of predictive ability in epidemiology. Managing the spread of infectious diseases requires processing quantitative epidemiological data and the ability to capture the dynamics of the infectious disease in order to provide a measure of control.

In this thesis, I have introducing cognitive biases in diseases spread modeling. For the first time, to the author's knowledge, the human subjective experience has …

Safety Assessment For Tipranavir : A Protease Inhibitor Treatment For Hiv Infected Adults, Jaromir Mikl

Legacy Theses & Dissertations (2009 - 2024)

Dose-limiting adverse events associated with anti-retroviral therapy (ART) generally include gastro-intestinal (GI) issues such as vomiting and nausea. However, serious adverse events (SAEs) do occur, the most frequent of which include liver toxicities and renal impairment as well as recent evidence of cardio-vascular disease (CVD) risk.

Respondent Driven Sampling : Feasibility, Validation And Its Potential Use For Estimating Health Indicators For Large General Populations, Robin Lee

Legacy Theses & Dissertations (2009 - 2024)

BACKGROUND: Researchers use many methods to collect population-based health indicator data. Random digit dial (RDD) is one frequently used method; however decreasing sample coverage and non-response bias have researchers searching for alternative methods. We hypothesize that respondent driven sampling (RDS) is a cost effective alternative. In accordance with this hypothesis we propose three objectives: 1) assess the mechanics, feasibility, and representativeness of RDS in producing valid estimates of health indicator data; 2) evaluate the feasibility in using RDS in comparison to RDD to collect health indicator data from a general population; and 3) report on data collected using RDS, specifically …

The Utility Of The Behavioral Risk Factor Surveillance System In Testing Quality Of Life Theory : An Evaluation Using Structural Equation Modeling, Evelyn Marie Kintner

Legacy Theses & Dissertations (2009 - 2024)

This study is a secondary data analysis that uses structural equation modeling (SEM) to assess the utility of the Behavioral Risk Factor Surveillance System (BRFSS)--the Centers for Disease Control's premier surveillance tool for monitoring behavioral risk factors--in predicting health related quality of life (HRQoL). Employing the statistical package SPSS/AMOS (version 7), the study utilizes New York State data extracted from the 2007 BRFSS national dataset to assess how well the observed pattern of variances and covariances of the state level data fit with a well-known HRQoL model developed by Wilson and Cleary (1995). Interaction effects are examined, utilizing a multigroup …

Prevention Of Human Papillomavirus (Hpv) Infection And Hpv-Related Diseases : Barriers To Hpv Vaccine Coverage Among University Women In The U.S., And Initial Steps In Integrating Cervical Cytology Testing Into Primary Care In The Republic Of Georgia, Robert Bednarczyk

Legacy Theses & Dissertations (2009 - 2024)

Worldwide, cervical cancer is second only to breast cancer in incidence. Screening for pre-cancerous abnormalities can reduce cervical cancer incidence and mortality, though this is not uniformly used worldwide. Recently, a vaccine against human papillomavirus (HPV), a necessary cause of cervical cancer, was approved for preventive use in the United States.

Immigration And Obesity In African American Adults Residing In The United States, Julius N. Ade

Walden Dissertations and Doctoral Studies

Obesity increases risk for heart disease, hypertension and other chronic diseases, and it affects minority ethnic groups disproportionately. However, it is unknown if African American immigrant adults, an increasing segment of the population, are at higher risk for obesity than African American non-immigrant adults residing in the United States. This study examined the association of obesity and immigrant status by comparing African American immigrant adults now residing in the United States to the general population of African American adults. The socio-ecological model provided the conceptual framework for this study. This study used a cross-sectional quantitative self-administered web-based survey to collect …

The Relationship Between Mosquito Abundance And Rice Field Density In The Republic Of Korea, Erin E. Richards, Penny Masuoka, David Brett-Major, Matthew Smith, Terry A. Klein, Heung Chul Kim, Assaf Anyamba, John Grieco

Journal Articles: Epidemiology

BACKGROUND: Japanese encephalitis virus (JEV), the causative agent of Japanese encephalitis (JE), is endemic to the Republic of Korea (ROK) where unvaccinated United States (U.S.) military Service members, civilians and family members are stationed. The primary vector of the JEV in the ROK is Culex tritaeniorhynchus. The ecological relationship between Culex spp. and rice fields has been studied extensively; rice fields have been shown to increase the prevalence of Cx. tritaeniorhynchus. This research was conducted to determine if the quantification of rice field land cover surrounding U.S. military installations in the ROK should be used as a parameter in a …

Prevalence Of Oral Mucosal Lesions And Related Risk Habits In Outpatient Dental Clinics In Malaysia And Yemen., Raji M. S. Hajeb

Student Works (2010-2019)

The purpose of this study is to determine and compare the prevalence of oral mucosal lesions (OML) and related risk habits and the influence of these habits on oral mucosal lesion prevalence among dental outpatients in Malaysia and Yemen during the period from May to October 2009. A total of 554 and 520 dental outpatients from Malaysia and Yemen with mean ages of 41.9± 17.04 years and 36.6±15.62 years respectively were interviewed and examined. The prevalence of OML namely (oral malignant lesions, potentially malignant disorders and other lesions) in Malaysia was 23.29% while the prevalence of oral mucosal lesions in …

Social Capital Variables As Predictors Of Hiv Risk-Taking Behaviors Among Sub-Saharan African Immigrants In The United States, Gbadebo Ogundiran Ogungbade

Walden Dissertations and Doctoral Studies

Vulnerable populations, including immigrants, are often at risk for human immunodeficiency virus (HIV) infection because of their risk-taking behaviors. This study investigated risk-taking behavior for HIV infection among Sub-Saharan African (SSA) immigrants in United States. Using social capital as a theoretical foundation, the study aimed to address the question, is there any association between social capital assets of educational opportunity, employment, and eligibility for social assistance and HIV risk-taking behavior, defined as condom use before sex (CUBS) among SSA immigrant in the U.S? Potential participants were recruited through religious and social organizations in a southwestern US state. The survey generated …

The Effect Of Direct Contact On Public Attitudes Towards People Living With Human Immunodeficiency Virus (Hiv) And Acquired Immune Deficiency Syndrome (Aids) In Zimbabweans, Mavis Mashingaidze

Walden Dissertations and Doctoral Studies

Stigma surrounding HIV and AIDS poses a significant threat to the curtailing of the epidemic by acting as a barrier to HIV testing and disclosure of serostatus. Previous research in the United States found personal knowledge of someone with HIV/AIDS to be a predictor of lower levels of HIV/AIDS-related stigma. However, no study to date has examined this relationship in Zimbabweans. Allport's contact hypothesis was hypothesis was the theoretical frame used to assess the effect of direct contact on public attitudes towards people living with the human immunodeficiency virus (HIV) and acquired immune deficiency syndrome (AIDS) in Zimbabweans with the …

The Latina/O Mental Health Paradox Or Racial/Ethnic Disparities? Depression Among New Immigrants To The U.S, Sandra Iveth Ramirez

Open Access Theses & Dissertations

The Latino/a Mental Health Paradox states that the foreign-born immigrants have better mental health outcomes when compared with native-born groups of various ethno-racial backgrounds, with the gap in mental stress minimizing overtime. The objective of this study is to examine whether Latina/os immigrants suffer an ethno-racial disparity in mental health or if they have favorable mental health outcomes as predicted by the Paradox. Expanding on the Latina/o Mental Health Paradox, rather than comparing Latina/o immigrants with native-born, this study will compare depression among recently legalized Latina/os with recent legalized European immigrants.

The Mediating Role Of Psychological Distress In The Relationship Between Adverse Childhood Experiences And Adult Smoking, Tara Wynn Strine

Walden Dissertations and Doctoral Studies

While research has indicated that impaired mental health partially mediates the relationship between adverse childhood experiences (ACEs) and alcohol and illicit drug use, little research has examined potential mediators in the relationship between ACEs and smoking, the number one cause of preventable mortality in the United States. Accordingly, this study examined the potential mediating effect of psychological distress on the relationship between ACES and smoking using data from Wave II of the ACE Study, a cross-sectional study completed between June and October of 1997 on a sample of adult health maintenance organization members (N = 7,211). The theoretical underpinnings for …