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Full-Text Articles in Medicine and Health Sciences

Dynapenic Obesity And The Effect On Long-Term Physical Function And Quality Of Life: Data From The Osteoarthritis Initiative, John A. Batsis, Alicia J. Zbehlik, Dawna Pidgeon, Stephen J. Bartels Oct 2015

Dynapenic Obesity And The Effect On Long-Term Physical Function And Quality Of Life: Data From The Osteoarthritis Initiative, John A. Batsis, Alicia J. Zbehlik, Dawna Pidgeon, Stephen J. Bartels

Dartmouth Scholarship

Obesity is associated with functional impairment, institutionalization, and increased mortality risk in elders. Dynapenia is defined as reduced muscle strength and is a known independent predictor of adverse events and disability. The synergy between dynapenia and obesity leads to worse outcomes than either independently. We identified the impact of dynapenic obesity in a cohort at risk for and with knee osteoarthritis on function.


Spectral Gene Set Enrichment (Sgse), H Robert Frost, Zhigang Li, Jason H. Moore Mar 2015

Spectral Gene Set Enrichment (Sgse), H Robert Frost, Zhigang Li, Jason H. Moore

Dartmouth Scholarship

Gene set testing is typically performed in a supervised context to quantify the association between groups of genes and a clinical phenotype. In many cases, however, a gene set-based interpretation of genomic data is desired in the absence of a phenotype variable. Although methods exist for unsupervised gene set testing, they predominantly compute enrichment relative to clusters of the genomic variables with performance strongly dependent on the clustering algorithm and number of clusters. We propose a novel method, spectral gene set enrichment (SGSE), for unsupervised competitive testing of the association between gene sets and empirical data sources. SGSE first computes …


Gene Expression Changes Reflect Clinical Response In A Placebo-Controlled Randomized Trial Of Abatacept In Patients With Diffuse Cutaneous Systemic Sclerosis, Eliza F. Chakravarty, Viktor Martyanov, David Fiorentino, Tammara A. Wood, David J. Haddon, Justin A. Jarrell, Paul Utz, Mark Genovese, Michael Whitfield, Lorinda Chung Jan 2015

Gene Expression Changes Reflect Clinical Response In A Placebo-Controlled Randomized Trial Of Abatacept In Patients With Diffuse Cutaneous Systemic Sclerosis, Eliza F. Chakravarty, Viktor Martyanov, David Fiorentino, Tammara A. Wood, David J. Haddon, Justin A. Jarrell, Paul Utz, Mark Genovese, Michael Whitfield, Lorinda Chung

Dartmouth Scholarship

Systemic sclerosis is an autoimmune disease characterized by inflammation and fibrosis of the skin and internal organs. We sought to assess the clinical and molecular effects associated with response to intravenous abatacept in patients with diffuse cutaneous systemic.


Wordless Intervention For Epilepsy In Learning Disabilities (Wield): Study Protocol For A Randomized Controlled Feasibility Trial, Marie-Anne Durand, Bob Gates, Georgina Parkes, Asif Zia Nov 2014

Wordless Intervention For Epilepsy In Learning Disabilities (Wield): Study Protocol For A Randomized Controlled Feasibility Trial, Marie-Anne Durand, Bob Gates, Georgina Parkes, Asif Zia

Dartmouth Scholarship

Epilepsy is the most common neurological problem that affects people with learning disabilities. The high seizure frequency, resistance to treatments, associated skills deficit and co-morbidities make the management of epilepsy particularly challenging for people with learning disabilities. The Books Beyond Words booklet for epilepsy uses images to help people with learning disabilities manage their condition and improve quality of life. Our aim is to conduct a randomized controlled feasibility trial exploring key methodological, design and acceptability issues, in order to subsequently undertake a large-scale randomized controlled trial of the Books Beyond Words booklet for epilepsy.


Successful Mdr-Tb Treatment Regimens Including Amikacin Are Associated With High Rates Of Hearing Loss, Chawangwa Modongo, Rafal S. Sobota, Boikobo Kesenogile, Ronald Ncube Oct 2014

Successful Mdr-Tb Treatment Regimens Including Amikacin Are Associated With High Rates Of Hearing Loss, Chawangwa Modongo, Rafal S. Sobota, Boikobo Kesenogile, Ronald Ncube

Dartmouth Scholarship

Aminoglycosides are a critical component of multidrug-resistant tuberculosis (MDR-TB) treatment but data on their efficacy and adverse effects in Botswana is scarce. We determined the effect of amikacin on treatment outcomes and development of hearing loss in MDR-TB patients. Patients started on MDR-TB treatment between 2006 and 2012 were included. Multivariate analysis was used to determine the effect of amikacin on treatment outcomes and development of hearing loss.


New Malignancies After Squamous Cell Carcinoma And Melanomas: A Population-Based Study From Norway, Trude E. Robsahm, Margaret R. Karagas, Judy R. Rees, Astri Syse Mar 2014

New Malignancies After Squamous Cell Carcinoma And Melanomas: A Population-Based Study From Norway, Trude E. Robsahm, Margaret R. Karagas, Judy R. Rees, Astri Syse

Dartmouth Scholarship

Skin cancer survivors experience an increased risk for subsequent malignancies but the associated risk factors are poorly understood. This study examined the risk of a new primary cancer following an initial skin cancer and assessed risk factors associated with second primary cancers.


Balancing The Presentation Of Information And Options In Patient Decision Aids: An Updated Review, Purva Abhyankar, Robert J. Volk, Jennifer Blumenthal-Barby, Paulina Bravo, Angela Buchholz, Elissa Ozanne, Dale C. Vidal, Nananda Col, Peep Stalmeier Nov 2013

Balancing The Presentation Of Information And Options In Patient Decision Aids: An Updated Review, Purva Abhyankar, Robert J. Volk, Jennifer Blumenthal-Barby, Paulina Bravo, Angela Buchholz, Elissa Ozanne, Dale C. Vidal, Nananda Col, Peep Stalmeier

Dartmouth Scholarship

Standards for patient decision aids require that information and options be presented in a balanced manner; this requirement is based on the argument that balanced presentation is essential to foster informed decision making. If information is presented in an incomplete/non-neutral manner, it can stimulate cognitive biases that can unduly affect individuals’ knowledge, perceptions of risks and benefits, and, ultimately, preferences. However, there is little clarity about what constitutes balance, and how it can be determined and enhanced. We conducted a literature review to examine the theoretical and empirical evidence related to balancing the presentation of information and options.


Ensemble-Based Methods For Forecasting Census In Hospital Units, Devin C. Koestler, Hernando Ombao, Jesse Bender May 2013

Ensemble-Based Methods For Forecasting Census In Hospital Units, Devin C. Koestler, Hernando Ombao, Jesse Bender

Dartmouth Scholarship

The ability to accurately forecast census counts in hospital departments has considerable implications for hospital resource allocation. In recent years several different methods have been proposed forecasting census counts, however many of these approaches do not use available patient-specific information. In this paper we present an ensemble-based methodology for forecasting the census under a framework that simultaneously incorporates both (i) arrival trends over time and (ii) patient-specific baseline and time-varying information. The proposed model for predicting census has three components, namely: current census count, number of daily arrivals and number of daily departures. To model the number of daily arrivals, …


Pilot Comparative Effectiveness Study Of Surface Perturbation Treadmill Training To Prevent Falls In Older Adults, Jon D. Lurie, Alexandra B. Zagaria, Dawna M. Pidgeon, Judith L. Forman, Kevin Spratt May 2013

Pilot Comparative Effectiveness Study Of Surface Perturbation Treadmill Training To Prevent Falls In Older Adults, Jon D. Lurie, Alexandra B. Zagaria, Dawna M. Pidgeon, Judith L. Forman, Kevin Spratt

Dartmouth Scholarship

Falls are the leading cause of fatal and non-fatal injuries among older adults. Exercise programs appear to reduce fall risk, but the optimal type, frequency, and duration of exercise is unknown. External perturbations such as tripping and slipping are a major contributor to falls, and task-specific perturbation training to enhance dynamic stability has emerged as a promising approach to modifying fall risk. The purpose of this pilot study was 1) to determine the feasibility of conducting a large pragmatic randomized trial comparing a multidimensional exercise program inclusive of the surface perturbation treadmill training (SPTT) to multidimensional exercise alone (Standard PT); …


Observational Intensity Bias Associated With Illness Adjustment: Cross Sectional Analysis Of Insurance Claims, J. E. Wennberg, D. O. Staiger, S. M. Sharp, D. J. Gottlieb Feb 2013

Observational Intensity Bias Associated With Illness Adjustment: Cross Sectional Analysis Of Insurance Claims, J. E. Wennberg, D. O. Staiger, S. M. Sharp, D. J. Gottlieb

Dartmouth Scholarship

Objective: To determine the bias associated with frequency of visits by physicians in adjusting for illness, using diagnoses recorded in administrative databases.

Setting: Claims data from the US Medicare program for services provided in 2007 among 306 US hospital referral regions.

Design: Cross sectional analysis. Participants 20% sample of fee for service Medicare beneficiaries residing in the United States in 2007 (n=5 153 877).


Multiple Subject Barycentric Discriminant Analysis (Musubada): How To Assign Scans To Categories Without Using Spatial Normalization, Hervé Abdi, Lynne J. Williams, Andrew C. Connolly, M. Ida Gobbini Dec 2012

Multiple Subject Barycentric Discriminant Analysis (Musubada): How To Assign Scans To Categories Without Using Spatial Normalization, Hervé Abdi, Lynne J. Williams, Andrew C. Connolly, M. Ida Gobbini

Dartmouth Scholarship

We present a new discriminant analysis (DA) method called Multiple Subject Barycentric Discriminant Analysis (MUSUBADA) suited for analyzing fMRI data because it handles datasets with multiple participants that each provides different number of variables (i.e., voxels) that are themselves grouped into regions of interest (ROIs). Like DA, MUSUBADA (1) assigns observations to predefined categories, (2) gives factorial maps displaying observations and categories, and (3) optimally assigns observations to categories. MUSUBADA handles cases with more variables than observations and can project portions of the data table (e.g., subtables, which can represent participants or ROIs) on the factorial maps. Therefore MUSUBADA can …


Dna Methylation Arrays As Surrogate Measures Of Cell Mixture Distribution, Eugene Houseman, William P. Accomando, Devin C. Koestler, Brock C. Christensen, Carmen J. Marsit May 2012

Dna Methylation Arrays As Surrogate Measures Of Cell Mixture Distribution, Eugene Houseman, William P. Accomando, Devin C. Koestler, Brock C. Christensen, Carmen J. Marsit

Dartmouth Scholarship

There has been a long-standing need in biomedical research for a method that quantifies the normally mixed composition of leukocytes beyond what is possible by simple histological or flow cytometric assessments. The latter is restricted by the labile nature of protein epitopes, requirements for cell processing, and timely cell analysis. In a diverse array of diseases and following numerous immune-toxic exposures, leukocyte composition will critically inform the underlying immuno-biology to most chronic medical conditions. Emerging research demonstrates that DNA methylation is responsible for cellular differentiation, and when measured in whole peripheral blood, serves to distinguish cancer cases from controls.


Assessing Medicare Beneficiaries’ Strength‐Of‐Preference Scores For Health Care Options: How Engaging Does The Elicitation Technique Need To Be?, Trafford Crump, Hilary A. Llewellyn-Thomas Jul 2011

Assessing Medicare Beneficiaries’ Strength‐Of‐Preference Scores For Health Care Options: How Engaging Does The Elicitation Technique Need To Be?, Trafford Crump, Hilary A. Llewellyn-Thomas

Dartmouth Scholarship

The objective was to determine if participants’ strength‐of‐preference scores for elective health care interventions at the end‐of‐life (EOL) elicited using a non‐engaging technique are affected by their prior use of an engaging elicitation technique.


Smoking Enhances Risk For New External Genital Warts In Men, Dorothy J. Wiley, David Elashoff, Emmanuel V. Masongsong, Diane M. Harper Mar 2009

Smoking Enhances Risk For New External Genital Warts In Men, Dorothy J. Wiley, David Elashoff, Emmanuel V. Masongsong, Diane M. Harper

Dartmouth Scholarship

Repeat episodes of HPV-related external genital warts reflect recurring or new infections. No study before has been sufficiently powered to delineate how tobacco use, prior history of EGWs and HIV infection affect the risk for new EGWs. Behavioral, laboratory and examination data for 2,835 Multicenter AIDS Cohort Study participants examined at 21,519 semi-annual visits were evaluated. Fourteen percent (391/2835) of men reported or were diagnosed with EGWs at 3% (675/21,519) of study visits. Multivariate analyses showed smoking, prior episodes of EGWs, HIV infection and CD4+ T-lymphocyte count among the infected, each differentially influenced the risk for new EGWs.


Abstracts In High Profile Journals Often Fail To Report Harm, Enrique Bernal-Delgado, Elliot S. Fisher Mar 2008

Abstracts In High Profile Journals Often Fail To Report Harm, Enrique Bernal-Delgado, Elliot S. Fisher

Dartmouth Scholarship

To describe how frequently harm is reported in the abstract of high impact factor medical journals. We carried out a blinded structured review of a random sample of 363 Randomised Controlled Trials (RCTs) carried out on human beings, and published in high impact factor medical journals in 2003. Main endpoint: 1) Proportion of articles reporting harm in the abstract; and 2) Proportion of articles that reported harm in the abstract when harm was reported in the main body of the article. Analysis: Corrected Prevalence Ratio (cPR) and its exact confidence interval were calculated. Non-conditional logistic regression was used.


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.


Associations Among Hospital Capacity, Utilization, And Mortality Of Us Medicare Beneficiaries, Controlling For Sociodemographic Factors., E. S. Fisher, J. E. Wennberg, T. A. Stukel, J. S. Skinner, S. M. Sharp Feb 2000

Associations Among Hospital Capacity, Utilization, And Mortality Of Us Medicare Beneficiaries, Controlling For Sociodemographic Factors., E. S. Fisher, J. E. Wennberg, T. A. Stukel, J. S. Skinner, S. M. Sharp

Dartmouth Scholarship

To explore whether geographic variations in Medicare hospital utilization rates are due to differences in local hospital capacity, after controlling for socioeconomic status and disease burden, and to determine whether greater hospital capacity is associated with lower Medicare mortality rates.


A Longitudinal Study Of Hospitalization Rates For Patients With Chronic Disease: Results From The Medical Outcomes Study., Eugene C. Nelson, Colleen A. Mchorney, Willard G. Manning, W H. Rogers Mar 1998

A Longitudinal Study Of Hospitalization Rates For Patients With Chronic Disease: Results From The Medical Outcomes Study., Eugene C. Nelson, Colleen A. Mchorney, Willard G. Manning, W H. Rogers

Dartmouth Scholarship

To prospectively compare inpatient and outpatient utilization rates between prepaid (PPD) and fee-for-service (FFS) insurance coverage for patients with chronic disease. Data from the Medical Outcomes Study, a longitudinal observational study of chronic disease patients conducted in Boston, Chicago, and Los Angeles.A four-year prospective study of resource utilization among 1,681 patients under treatment for hypertension, diabetes, myocardial infarction, or congestive heart failure in the practices of 367 clinicians.