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Articles 5311 - 5340 of 5495

Full-Text Articles in Epidemiology

Perceived Smoking Environment And Smoking Initiation Among Multi-Ethnic Urban Girls, Tracy R. Nichols, Amanda Birnbaum, Sara Birnel, Gilbert J. Botvin Apr 2006

Perceived Smoking Environment And Smoking Initiation Among Multi-Ethnic Urban Girls, Tracy R. Nichols, Amanda Birnbaum, Sara Birnel, Gilbert J. Botvin

Department of Public Health Scholarship and Creative Works

Purpose

To examine associations between the perceived smoking environment and smoking initiation among urban multi-ethnic adolescent girls in New York City.

Methods

Self-report surveys completed in grades 7, 8, and 9 assessed girls’ (n = 858) smoking initiation, and perceived smoking environment (family smoking, friends’ smoking, smoking norms, and cigarette availability). Carbon monoxide breath samples were collected from girls using a variation of the bogus pipeline procedure.

Results

Differences were found in smoking prevalence with white girls reporting the highest prevalence of smoking at baseline and the greatest increase in smoking prevalence from seventh to eighth grade. Black girls reported …


Different Public Health Interventions Have Varying Effects, Paula Diehr, Anne B. Newman, Liming Cai, Ann Derleth Feb 2006

Different Public Health Interventions Have Varying Effects, Paula Diehr, Anne B. Newman, Liming Cai, Ann Derleth

UW Biostatistics Working Paper Series

Objective: To compare performance of one-time health interventions to those that change the probability of transitioning from one health state to another. Study Design and Setting: We used multi-state life table methods to estimate the impact of eight types of interventions on several outcomes. Results: In a cohort beginning at age 65, curing all the sick persons at baseline would increase life expectancy by 0.23 years and increase years of healthy life by .54 years. An equal amount of improvement could be obtained with a 12% decrease in the probability of getting sick, a 16% increase in the probability of …


Tag Snp Selection For Finnish Individuals Based On The Ceph Utah Hapmap Database, Cristen J. Willer, Laura J. Scott, Lori L. Bonnycastle Feb 2006

Tag Snp Selection For Finnish Individuals Based On The Ceph Utah Hapmap Database, Cristen J. Willer, Laura J. Scott, Lori L. Bonnycastle

University Faculty Publications and Creative Works

The pattern and nature of linkage disequilibrium in the human genome is being studied and catalogued as part of the International HapMap Project [2003: Nature 426:789-796]. A key goal of the HapMap Project is to enable identification of tag single nucleotide polymorphisms (SNPs) that capture a substantial portion of common human genetic variability while requiring only a small fraction of SNPs to be genotyped [International HapMap Consortium, 2005: Nature 437:1299-1320]. In the current study, we examined the effectiveness of using the CEU HapMap database to select tag SNPs for a Finnish sample. We selected SNPs in a 17.9-Mb region of …


Gpnn: Power Studies And Applications Of A Neural Network Method For Detecting Gene-Gene Interactions In Studies Of Human Disease, Alison A. Motsinger, Stephen L. Lee, George Mellick, Marylyn D. Ritchie Jan 2006

Gpnn: Power Studies And Applications Of A Neural Network Method For Detecting Gene-Gene Interactions In Studies Of Human Disease, Alison A. Motsinger, Stephen L. Lee, George Mellick, Marylyn D. Ritchie

Dartmouth Scholarship

The identification and characterization of genes that influence the risk of common, complex multifactorial disease primarily through interactions with other genes and environmental factors remains a statistical and computational challenge in genetic epidemiology. We have previously introduced a genetic programming optimized neural network (GPNN) as a method for optimizing the architecture of a neural network to improve the identification of gene combinations associated with disease risk. The goal of this study was to evaluate the power of GPNN for identifying high-order gene-gene interactions. We were also interested in applying GPNN to a real data analysis in Parkinson's disease.


The Role Of Radiation Therapy On Medically Inoperable Clinically Localized Non-Small Cell Lung Patients: London Regional Cancer Program (Lrcp) Clinical Experience, Michael Lee, Edward Yu, Robert Ash, Patricia Tai, Larry Stitt, George Rodrigues, Rashid Dar, Mark Vincent, Richard Inculet, Richard Malthaner Jan 2006

The Role Of Radiation Therapy On Medically Inoperable Clinically Localized Non-Small Cell Lung Patients: London Regional Cancer Program (Lrcp) Clinical Experience, Michael Lee, Edward Yu, Robert Ash, Patricia Tai, Larry Stitt, George Rodrigues, Rashid Dar, Mark Vincent, Richard Inculet, Richard Malthaner

Oncology Presentations

Lung cancer is the most frequent cause of cancer death in both men and women in North America. In 2006, an estimated 22,700 Canadians will be diagnosed with lung cancer and 19,300 will die of it (Canadian Cancer Statistics 2006).

Approximately 15-20% of NSCLC patients present with early or localized disease.

Surgical resection of T1-2N0 NSCLC remains the treatment of choice for this population, and results in a 5-year survival rate of 50-70%.

Patients deemed medically inoperable have been treated with non-surgical therapies, such as radiation therapy(RT), while some patients have simply been observed without any tumor therapy because of …


Cyclosporin Versus Tacrolimus For Liver Transplanted Patients, Elizabeth Haddad, Vivian Mcalister, Elizabeth Renouf, Richard Malthaner, Mette S. Kjaer, Lise Lotte Gluud Jan 2006

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

Surgery Publications

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 …


Laboratory Diagnosis Of Tuberculosis In Primary Care, David Brett-Major, Thomas E. Walsh Jan 2006

Laboratory Diagnosis Of Tuberculosis In Primary Care, David Brett-Major, Thomas E. Walsh

Journal Articles: Epidemiology

No abstract provided.


Need For Cognition And Message Complexity In Motivating Fruit And Vegetable Intake Among Callers To The Cancer Information Service, Pamela Williams-Piehota, Judith Pizarro, Stephanie A. Navarro Silvera, Linda Mowad, Peter Salovey Jan 2006

Need For Cognition And Message Complexity In Motivating Fruit And Vegetable Intake Among Callers To The Cancer Information Service, Pamela Williams-Piehota, Judith Pizarro, Stephanie A. Navarro Silvera, Linda Mowad, Peter Salovey

Department of Public Health Scholarship and Creative Works

This field experiment examined the impact of an individual's need for cognition (NFC; the tendency to enjoy thinking deeply about issues), complex versus simple messages, and the interaction of NFC and message type on encouraging fruit and vegetable consumption. Callers to the Cancer Information Service of the National Cancer Institute (N = 517) were asked to participate in the experiment at the end of their call. Individual NFC was assessed, and participants were assigned randomly to receive a telephone message promoting fruit and vegetable consumption that was either complex and multifaceted or simple and straightforward. Similarly constructed brochures were mailed …


Determinants Of Dating Violence Among Youth In The U.S., Candace Hamm Jan 2006

Determinants Of Dating Violence Among Youth In The U.S., Candace Hamm

Theses and Dissertations

Background: Physical Dating Violence (PDV) victimization is a major public health concern among adolescents in the United States. Research has shown that determinants of PDV victimization are different for male and female adolescents. However, inconsistent findings entail that further research needs to be done using a representative sample of male and female adolescents.Objective: To identify gender-specific determinants of PDV victimization utilizing a nationally representative sample of high school adolescents.Methods: Data from the 2005 National Youth Risk Behavior Survey was used for this analysis. The study population included 6.951 male and 6,807 female students in grades 9 through 12. Bivariate and …


A Needs Assessment For Annual Physical Examination For Selected Richmond Public School Children, Aimee Gibbs Jan 2006

A Needs Assessment For Annual Physical Examination For Selected Richmond Public School Children, Aimee Gibbs

Theses and Dissertations

Introduction: The following risk factors have found to be associated with inadequate health care and have been found to affect the well-being of children: racial or ethnic minority, poverty status, median family income, family structure of household, maternal education level, and parental employment status. Also, there has found to be health indicators including, teen pregnancy, asthma hospitalization, and lead poisoning cases that affect the well-being of a child and are associated with the presence of these risk factors in a population. Objectives: The objectives of this study is to (1) compare the presence of risk factors and health indicators in …


Predictors Of Primary Elective Cesarean Delivery Among Apparently Healthy Pregnant Women In Virginia, Brooke W. Rossheim Jan 2006

Predictors Of Primary Elective Cesarean Delivery Among Apparently Healthy Pregnant Women In Virginia, Brooke W. Rossheim

Theses and Dissertations

Objectives. The purpose of this cross-sectional study was to evaluate whether certain maternal variables were associated with the performance of a primary cesarean delivery rather than a spontaneous vaginal delivery among apparently healthy pregnant women in the Commonwealth of Virginia.Methods. This study utilized the 2004 Virginia Statistics File for Live Births which contained 103,830 records. From this dataset, the following groups of women were excluded: multiparous women, women who had had a previous delivery by any method, women with medical and obstetric problems, women with any labor and delivery complications, women with premature births and women with multiple gestations. The …


The Effect Of Advertising On Attitudes Toward Tobacco Use And Decisions About Smoking Among Virginia Adolescents, John Rosser Matthews Iii Jan 2006

The Effect Of Advertising On Attitudes Toward Tobacco Use And Decisions About Smoking Among Virginia Adolescents, John Rosser Matthews Iii

Theses and Dissertations

Purpose: This study seeks to determine 1) whether the type of advertising exposure is associated with adolescent health perceptions of tobacco use, and 2) whether the type of media exposure is associated with initiation plans (non-smokers) or quitting plans (smokers). Methods: This was a cross-sectional survey of middle school students (n=l1,128).Psychosocial variables were knowledge of the risks of tobacco use (range: 3-15) and benefits of being tobacco free (range: 7-35) with higher scores indicating greater understanding. Intentions to quit or initiate were construed as binary variables. Exposure variables were tobacco advertisements or anti-tobacco media messages. Covariates were gender, race, grade …


Knowledge And Perceived Ambiguity Of Physical Activity Recommendations And Physical Activity In Men And Women In The United States, Laura G. Kiken Jan 2006

Knowledge And Perceived Ambiguity Of Physical Activity Recommendations And Physical Activity In Men And Women In The United States, Laura G. Kiken

Theses and Dissertations

Background: The majority of Americans - especially women - do not meet physical activity recommendations. Having physical activity goals has been associated with physical activity participation, and physical activity recommendations set by public health experts can be viewed as externally set goals. However, past research has shown that goals that are specific rather than ambiguous are more likely to be achieved, and variations in recommendations over time and across sources may have created perceived goal ambiguity.Objectives: This study aimed to (1) examine the extent of physical activity recommendation knowledge among adults in the United States, (2) quantify perceptions of the …


Cutaneous And Presumed Visceral Leishmaniasis In A Soldier Deployed To Afghanistan, James P. Woodrow, Joshua D. Hartzell, Jim Czarnik, David Brett-Major, Glenn Wortmann Jan 2006

Cutaneous And Presumed Visceral Leishmaniasis In A Soldier Deployed To Afghanistan, James P. Woodrow, Joshua D. Hartzell, Jim Czarnik, David Brett-Major, Glenn Wortmann

Journal Articles: Epidemiology

Leishmaniasis has been frequently diagnosed in US military personnel returning from duty in Southwest Asia. The majority of cases have demonstrated cutaneous disease, although a few cases of visceral disease have been documented. We present the case of an immunocompetent, HIV-negative, US Army soldier who suffered both visceral and cutaneous manifestations of leishmaniasis after returning from deployment in Afghanistan. Overlap of cutaneous and visceral involvement is rare and has not been reported in our cohort. Latent Plasmodium vivax infection may have been an exacerbating cofactor. We discuss this case and present a review of the literature.


C - Reactive Protein, Coronary Heart Disease And Ischemic Stroke In The Elderly: The Cardiovascular Health Study, Xia Li Jan 2006

C - Reactive Protein, Coronary Heart Disease And Ischemic Stroke In The Elderly: The Cardiovascular Health Study, Xia Li

Theses and Dissertations

Background: C-reactive protein (CRP) has been associated with increased risk of coronary heart disease (CHD) and stroke, but much of the research had focused on middle-aged populations with, limited prospective, population-based, longitudinal data. In this study, we examined data from an elderly population and described the distribution of CRP concentrations and the prevalence of elevated CRP levels (>3 mg/l), examined the association between CRP levels and incidence of CHD or ischemic stroke, and assessed the potential interaction of CRP with sex or race on the incidence of CHD or ischemic stroke.Methods: Baseline CRP levels were measured in a cohort …


Lack Of Knowledge Of Mother-To-Child Transmission In Kenya Among Women Ages 15-49, Nisha Warrier Jan 2006

Lack Of Knowledge Of Mother-To-Child Transmission In Kenya Among Women Ages 15-49, Nisha Warrier

Theses and Dissertations

Purpose: The epidemic of mother-to-child transmission (MTCT) of HIV/AIDS in resource-poor countries is dramatic; it is responsible for nearly 90% of childhood infections. The primary purpose of analysis was to understand the distribution of factors and their association with lack of knowledge of MTCT in Kenya. In parallel, another aim was to identify the relationship between media, particularly frequency of radio exposure, and lack of knowledge.Methods: This study used the 2003 Kenya Demographic and Health Survey (DHS) collected for 8,195 women, ages 15-49. Descriptive analysis, univariate analysis, and logistic regression were completed on SPSS 14 software.Results: In the sample, 1151 …


The Association Between Breast Feeding And Being Overweight In Children, Naja Jamil Eldanaf Jan 2006

The Association Between Breast Feeding And Being Overweight In Children, Naja Jamil Eldanaf

Theses and Dissertations

Purpose: Obesity/Overweight in children is an epidemic and the most common disorder of childhood in the developed world. Prevalence is increasing, leading to short- and long-term complications. Breastfeeding may protect against childhood obesity, but the debate is ongoing. The main purpose of this project was to assess the relationship between breastfeeding and being overweight in early childhood.Methods: Data were collected from the State and Local Area Integrated Telephone survey; National Survey of Children's Health, 2003. Overall, 16,358 children, ages 3 to 5, were included in the sample. SPSS Complex Sample software was utilized to generate for all analyses. Complex samples …


Machismo As A Determinant For Hiv/Std Risk Behavior Among Latino Msm, Jacqueline L. Sears Jan 2006

Machismo As A Determinant For Hiv/Std Risk Behavior Among Latino Msm, Jacqueline L. Sears

Theses and Dissertations

Objective: Male-to-male sexual contact is the most common mode of transmission for HIV among Latino men. Psychosocial factors such as machismo, homophobic discrimination, and internalized homophobia have been hypothesized to greatly impact sexual behaviors among Latinos. However, studies investigating the relationship between these psychosocial factors and risky sexual behaviors are limited. This study examined the impact of machismo on risky sexual behaviors among Latino Male who have Sex with Men (MSM).Methods: This study utilized data collected from 254 Latino MSM in 1999 from selected cities within Virginia. The analysis focused on respondent demographic characteristics, psychosocial factors, acculturation, and sexual risky …


Association Between Smoking, Chemical Exposure And Hearing Loss In An Occupational Setting, Darlene W. Olive Jan 2006

Association Between Smoking, Chemical Exposure And Hearing Loss In An Occupational Setting, Darlene W. Olive

Theses and Dissertations

Objective: Twenty-two million Americans or roughly 8% of the population are hearing impaired. This affects more than just the ability for one to hear. In the last three decades, younger Americans have shown a sharp increase in hearing impairment. Hearing loss affects social and emotional well being and thus has the ability to decrease one's quality of life. This study was designed to examine the association between smoking, workplace chemical exposure, and hearing loss.Methods: This cross-sectional population-based study was conducted in an occupational health clinic setting in Virginia. The study population consisted of employees from local businesses who visited the …


Factors Associated With High Sexual Risk Behavior In Single Women, Thomas B. M. Leecost Jan 2006

Factors Associated With High Sexual Risk Behavior In Single Women, Thomas B. M. Leecost

Theses and Dissertations

Objective: This study was to identify factors associated with High Sexual Risk Behavior (HSRB) in single Afro American women seen in an Epidemiology/Sexual transmitted disease (EPID/STD) Clinic in Richmond, Virginia from January 2006 through April 2006.Method: Participants were 154 single women (no history of marriage) between the ages of 18-30 visiting the EPID/STD clinic for the first time.Demographic information was obtained from their records. A volunteer interview was given that contained 101 variables to evaluate for High Sexual Risk Behavior (HSRB). HSRB was defined to response 'yes' to the question, "During the past 3 months did you have sex with …


A Hybrid Model For Reducing Ecological Bias, Ruth Salway, Jon Wakefield Dec 2005

A Hybrid Model For Reducing Ecological Bias, Ruth Salway, Jon Wakefield

UW Biostatistics Working Paper Series

A major drawback of epidemiological ecological studies, in which the association between area-level summaries of risk and exposure are used to make inference about individual risk, is the difficulty in characterising within-area variability in exposure and confounder variables. To avoid ecological bias, samples of individual exposure/confounder data within each area are required. Unfortunately these may be difficult or expensive to obtain, particularly if large samples are required. In this paper we propose a new approach suitable for use with small samples. We combine a Bayesian non-parametric Dirichlet process prior with an estimating functions approach, and show that this model gives …


Health-Exposure Modelling And The Ecological Fallacy, Jon Wakefield, Gavin Shaddick Dec 2005

Health-Exposure Modelling And The Ecological Fallacy, Jon Wakefield, Gavin Shaddick

UW Biostatistics Working Paper Series

Recently there has been increased interest in modelling the association between aggregate disease counts and environmental exposures measured, for example via air pollution monitors, at point locations. This paper has two aims: first we develop a model for such data in order to avoid ecological bias; second we illustrate that modelling the exposure surface and estimating exposures may lead to bias in estimation of health effects. Design issues are also briefly considered, in particular the loss of information in moving from individual to ecological data, and the at-risk populations to consider in relation to the pollution monitor locations. The approach …


Ua12/2/1 College Heights Herald, Vol. 81, No. 23 [25], Wku Student Affairs Dec 2005

Ua12/2/1 College Heights Herald, Vol. 81, No. 23 [25], Wku Student Affairs

WKU Administration Documents

WKU campus newspaper reporting campus, athletic and Bowling Green, Kentucky news. Articles in this issue:

  • Leslie, Joey. More Students Tested During AIDS Day
  • Hupman, Samantha. J-term More Popular than Anticipated
  • Fontana, Alex. Student Government Association Proposes New Bicycles for Police
  • Bosken, Nina. Students Dodge, Duck, Dive for Charity and Prizes – Special Olympics
  • Richardson, Kelly. Kentucky Community Technical College System Requests Funding – KCTCS
  • Taking the Next Step – Cultural Diversity
  • Eoff, Allison. Pass on Adderall
  • Gabler, R. XXX Ads Disappointing
  • Williams, Suzanne. A Woman’s Heart
  • Hupman, Samantha. Two Fights Reported on Hill
  • Paul, Corey. Kwanzaa to Be Celebrated Today …


History-Adjusted Marginal Structural Models To Estimate Time-Varying Effect Modification , Maya L. Petersen, Steven G. Deeks, Jeffrey N. Martin, Mark J. Van Der Laan Dec 2005

History-Adjusted Marginal Structural Models To Estimate Time-Varying Effect Modification , Maya L. Petersen, Steven G. Deeks, Jeffrey N. Martin, Mark J. Van Der Laan

U.C. Berkeley Division of Biostatistics Working Paper Series

Much of epidemiology and clinical medicine is focused on the estimation of treatments or interventions administered over time. In such settings of longitudinal treatment, time-dependent confounding is often an important source of bias. Marginal structural models are a powerful tool for estimating the causal effect of a treatment using observational data, particularly when time-dependent confounding is present. Recent statistical work presented a generalization of marginal structural models, called history-adjusted marginal structural models. Unlike standard marginal structural models, history-adjusted marginal structural models can be used to estimate modification of treatment effects by time-varying covariates. Estimation of time-dependent causal effect modification is …


Chaotic Desynchronization Of Multistrain Diseases, Ira Schwartz, Leah Shaw, Derek Cummings, Lora Billings, Marie Mccrary, Donald Burke Dec 2005

Chaotic Desynchronization Of Multistrain Diseases, Ira Schwartz, Leah Shaw, Derek Cummings, Lora Billings, Marie Mccrary, Donald Burke

Department of Mathematics Faculty Scholarship and Creative Works

Multistrain diseases are diseases that consist of several strains, or serotypes. The serotypes may interact by antibody-dependent enhancement rADE, in which infection with a single serotype is asymptomatic, but infection with a second serotype leads to serious illness accompanied by greater infectivity. It has been observed from serotype data of dengue hemorrhagic fever that outbreaks of the four serotypes occur asynchronously. Both autonomous and seasonally driven outbreaks were studied in a model containing ADE. For sufficiently small ADE, the number of infectives of each serotype synchronizes, with outbreaks occurring in phase. When the ADE increases past a threshold, the system …


Population Intervention Models In Causal Inference, Alan E. Hubbard, Mark J. Van Der Laan Oct 2005

Population Intervention Models In Causal Inference, Alan E. Hubbard, Mark J. Van Der Laan

U.C. Berkeley Division of Biostatistics Working Paper Series

Marginal structural models (MSM) provide a powerful tool for estimating the causal effect of a] treatment variable or risk variable on the distribution of a disease in a population. These models, as originally introduced by Robins (e.g., Robins (2000a), Robins (2000b), van der Laan and Robins (2002)), model the marginal distributions of treatment-specific counterfactual outcomes, possibly conditional on a subset of the baseline covariates, and its dependence on treatment. Marginal structural models are particularly useful in the context of longitudinal data structures, in which each subject's treatment and covariate history are measured over time, and an outcome is recorded at …


Additive Hazards Models With Latent Treatment Effectiveness Lag Time, Ying Qing Chen, Charles A. Rohde, Mei-Cheng Wang Oct 2005

Additive Hazards Models With Latent Treatment Effectiveness Lag Time, Ying Qing Chen, Charles A. Rohde, Mei-Cheng Wang

Johns Hopkins University, Dept. of Biostatistics Working Papers

In many clinical trials to evaluate treatment efficacy, it is believed that there may exist latent treatment effectiveness lag times after which medical procedure or chemical compound would be in full effect. In this article, semiparametric regression models are proposed and studied to estimate the treatment effect accounting for such latent lag times. The new models take advantage of the invariance property of the additive hazards model in marginalizing over random effects, so parameters in the models are easy to be estimated and interpreted, while the flexibility without specifying baseline hazard function is kept. Monte Carlo simulation studies demonstrate the …


Gauss-Seidel Estimation Of Generalized Linear Mixed Models With Application To Poisson Modeling Of Spatially Varying Disease Rates, Subharup Guha, Louise Ryan Oct 2005

Gauss-Seidel Estimation Of Generalized Linear Mixed Models With Application To Poisson Modeling Of Spatially Varying Disease Rates, Subharup Guha, Louise Ryan

Harvard University Biostatistics Working Paper Series

Generalized linear mixed models (GLMMs) provide an elegant framework for the analysis of correlated data. Due to the non-closed form of the likelihood, GLMMs are often fit by computational procedures like penalized quasi-likelihood (PQL). Special cases of these models are generalized linear models (GLMs), which are often fit using algorithms like iterative weighted least squares (IWLS). High computational costs and memory space constraints often make it difficult to apply these iterative procedures to data sets with very large number of cases.

This paper proposes a computationally efficient strategy based on the Gauss-Seidel algorithm that iteratively fits sub-models of the GLMM …


Computational Techniques For Spatial Logistic Regression With Large Datasets, Christopher J. Paciorek, Louise Ryan Oct 2005

Computational Techniques For Spatial Logistic Regression With Large Datasets, Christopher J. Paciorek, Louise Ryan

Harvard University Biostatistics Working Paper Series

In epidemiological work, outcomes are frequently non-normal, sample sizes may be large, and effects are often small. To relate health outcomes to geographic risk factors, fast and powerful methods for fitting spatial models, particularly for non-normal data, are required. We focus on binary outcomes, with the risk surface a smooth function of space. We compare penalized likelihood models, including the penalized quasi-likelihood (PQL) approach, and Bayesian models based on fit, speed, and ease of implementation.

A Bayesian model using a spectral basis representation of the spatial surface provides the best tradeoff of sensitivity and specificity in simulations, detecting real spatial …


Estimation And Projection Of Indicence And Prevalence Based On Doubly Truncated Data With Application To Pharmacoepidemiological Databases, Henrik Stovring, Mei-Cheng Wang Oct 2005

Estimation And Projection Of Indicence And Prevalence Based On Doubly Truncated Data With Application To Pharmacoepidemiological Databases, Henrik Stovring, Mei-Cheng Wang

Johns Hopkins University, Dept. of Biostatistics Working Papers

Incidences of disease are of primary interest in any epidemiological analysis of disease spread in general populations. Ordinary estimates obtained from follow-up of an initially non-diseased cohort are costly, and so such estimates are not routinely available. In contrast, routine registers exist for many diseases with data on all detected cases within a given calendar time period, but lacking information on non-diseased. In the present work we show how this type of data supplemented with data on the past birth process can be analyzed to yield age specific incidence estimates as well as lifetime prevalence. A non-parametric model is studied …