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Full-Text Articles in Biostatistics

Aggressive Diuresis And Severity-Adjusted Length Of Hospital Stay In Acute Congestive Heart Failure Patients., Muhammad U. Butt M.D. Apr 2018

Aggressive Diuresis And Severity-Adjusted Length Of Hospital Stay In Acute Congestive Heart Failure Patients., Muhammad U. Butt M.D.

Muhammad Umer Butt M.D., MSCRD

To see if aggressive diuresis in 1st 24 hours is associated with a comparable number of total days in the hospital as compared to non-aggressive diuresis.  In this retrospective cohort study, we compared the length of hospital stay of consecutive patients admitted in one year based on their diuresis during the first twenty-four hours of hospitalization: aggressive diuresis (group 1) i.e. >2400mL versus non-aggressive diuresis (group 2) i.e. ≤ 2400mL urine output. Patients were excluded if in cardiogenic shock, had creatinine level above 3 mg/dL on admission, or on dialysis. A total of 194 patients were enrolled (29 in group …


Screening For Elder Mistreatment Among Older Adults Seeking Legal Assistance Services, Sheryl M. Strasser, Megan Smith, Scott Weaver, Shimin Zheng, Yan Cao May 2017

Screening For Elder Mistreatment Among Older Adults Seeking Legal Assistance Services, Sheryl M. Strasser, Megan Smith, Scott Weaver, Shimin Zheng, Yan Cao

Shimin Zheng

Introduction: The aging population is a rapidly growing demographic in the United States. Isolation, limited autonomy, and declining physical and mental health render many older adults vulnerable to elder mistreatment (EM). The purpose of this study was to assess the prevalence and correlates of EM among a sample of older adults using legal assistance services in Atlanta, Georgia. Methods: Researchers administered surveys to consenting older adults (aged 60þ) in 5 metro Atlanta community centers that hosted legal assistance information sessions as part of the Elderly Legal Assistance Program. The surveys screened for risk factors and prevalence of EM risk using …


Predictors Of Treatments Acceptable To Patients For Late-Life Depression, Gerald J. Jogerst, Shimin Zheng, Erik Vanderlip May 2017

Predictors Of Treatments Acceptable To Patients For Late-Life Depression, Gerald J. Jogerst, Shimin Zheng, Erik Vanderlip

Shimin Zheng

Objectives. Describe older patients’ perceptions about depression and characteristics associated with acceptance of treatments. Design. Cross-sectional study. Setting. Three primary care clinics in Iowa. Participants. Consecutive sample of 529 primary care patients. Measurements. Depression screening tool (a 9-item patient health questionnaire [PHQ-9]) and questionnaire including sociodemographic data, patient attitudes about depression, and acceptability of different treatments. Results. Mean age was 71.9 years (range 60–93 years), 314 (59%) female. Among the 529 participants, 93 (17.5%) had history of depression and 60 (11.3%) had PHQ-9 scores of 10 or greater. Participants believed depression is a disease for which they would use medication …


Neoadjuvant Or Adjuvant Therapy For Resectable Esophageal Cancer: A Systematic Review And Meta-Analysis, Richard Malthaner, Rebecca Wong, R. Rumble, Lisa Zuraw Jul 2015

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 Jul 2015

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 …


Neoadjuvant Or Adjuvant Therapy For Resectable Esophageal Cancer: A Systematic Review And Meta-Analysis, Richard Malthaner, Rebecca Wong, R. Rumble, Lisa Zuraw Jul 2015

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 Jul 2015

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 …


Leukoaraiosis Predicts Poor 90-Day Outcome After Acute Large Cerebral Artery Occlusion, Nils Henninger, Eugene Lin, Stephen Baker, Ajay Wakhloo, Deepak Takhtani, Majaz Moonis Apr 2015

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 Dec 2014

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 …


Bayesian Joint Selection Of Genes And Pathways: Applications In Multiple Myeloma Genomics, Lin Zhang, Jeffrey S. Morris, Jiexin Zhang, Robert Orlowski, Veerabhadran Baladandayuthapani Jan 2014

Bayesian Joint Selection Of Genes And Pathways: Applications In Multiple Myeloma Genomics, Lin Zhang, Jeffrey S. Morris, Jiexin Zhang, Robert Orlowski, Veerabhadran Baladandayuthapani

Jeffrey S. Morris

It is well-established that the development of a disease, especially cancer, is a complex process that results from the joint effects of multiple genes involved in various molecular signaling pathways. In this article, we propose methods to discover genes and molecular pathways significantly associ- ated with clinical outcomes in cancer samples. We exploit the natural hierarchal structure of genes related to a given pathway as a group of interacting genes to conduct selection of both pathways and genes. We posit the problem in a hierarchical structured variable selection (HSVS) framework to analyze the corresponding gene expression data. HSVS methods conduct …


Prediction Of Radiation Pneumonitis By Dose-Volume Histogram Parameters In Lung Cancer--A Systematic Review, George Rodrigues, Michael Lock, David D'Souza, Edward Yu, Jake Van Dyk Nov 2012

Prediction Of Radiation Pneumonitis By Dose-Volume Histogram Parameters In Lung Cancer--A Systematic Review, George Rodrigues, Michael Lock, David D'Souza, Edward Yu, Jake Van Dyk

Michael Lock

BACKGROUND AND PURPOSE: To perform a systematic review of the predictive ability of various dose-volume histogram (DVH) parameters (V(dose), mean lung dose (MLD), and normal tissue complication probability (NTCP)) in the incidence of radiation pneumonitis (RP) caused by external-beam radiation therapy.

METHODS AND MATERIALS: Studies assessing the relationship between CT-based DVH reduction parameters and RP rate in radically treated lung cancer were eligible for the review. Synonyms for RP, lung cancer, DVH and its associated parameters (NTCP, V(20), V(30), MLD) were combined in a search strategy involving electronic databases, secondary reference searching, and consultation with experts. Individual or group data …


Technology Assessment Of Automated Atlas Based Segmentation In Prostate Bed Contouring, Jeremiah Hwee, Alexander Louie, Stewart Gaede, Glenn Bauman, David D'Souza, Tracy Sexton, Michael Lock, Belal Ahmad, George Rodrigues Nov 2012

Technology Assessment Of Automated Atlas Based Segmentation In Prostate Bed Contouring, Jeremiah Hwee, Alexander Louie, Stewart Gaede, Glenn Bauman, David D'Souza, Tracy Sexton, Michael Lock, Belal Ahmad, George Rodrigues

Michael Lock

BACKGROUND: Prostate bed (PB) contouring is time consuming and associated with inter-observer variability. We evaluated an automated atlas-based segmentation (AABS) engine in its potential to reduce contouring time and inter-observer variability.

METHODS: An atlas builder (AB) manually contoured the prostate bed, rectum, left femoral head (LFH), right femoral head (RFH), bladder, and penile bulb of 75 post-prostatectomy cases to create an atlas according to the recent RTOG guidelines. 5 other Radiation Oncologists (RO) and the AABS contoured 5 new cases. A STAPLE contour for each of the 5 patients was generated. All contours were anonymized and sent back to the …


Advancing Stage Of Female Reproductive Life Associated With Bipolar Illness Exacerbation, Wendy K. Marsh, Terence Ketter, Sybil L. Crawford, Julia V. Johnson, Anthony J. Rothschild Sep 2011

Advancing Stage Of Female Reproductive Life Associated With Bipolar Illness Exacerbation, Wendy K. Marsh, Terence Ketter, Sybil L. Crawford, Julia V. Johnson, Anthony J. Rothschild

Sybil L. Crawford

Introduction: Perimenopause confers an increased risk of depression in the general population, yet bipolar disorder mood course remains unknown. Methods: Clinic visits in 519 premenopausal, 116 perimenopausal including 13 women transitioning from peri- to postmenopause, and 133 postmenopausal women with bipolar disorder who received naturalistic treatment in the multisite STEP-Bipolar Disorder study over 19.8 +/- 15.5 months were analyzed for mood state. Results: Advancing female reproductive stage was associated with significant decline in mood elevation; significant decline in euthymia; no significant difference in major depression; and symptomatic significant increase. Conclusions: Advancing stage of female reproductive life was associated with bipolar …


Body Mass Index, Treatment Practices, And Mortality In Patients With Acute Heart Failure, Timothy Fitzgibbons, Olga Hardy, Darleen Lessard, Joel Gore, Jorge Yarzebski, Robert Goldberg Jul 2010

Body Mass Index, Treatment Practices, And Mortality In Patients With Acute Heart Failure, Timothy Fitzgibbons, Olga Hardy, Darleen Lessard, Joel Gore, Jorge Yarzebski, Robert Goldberg

Jorge L. Yarzebski

OBJECTIVES: Obesity is associated with an increased risk of heart failure (HF). Among patients presenting with acute HF, however, differences in clinical characteristics, treatment regimens, and short-term prognosis of varying weights are largely unknown, particularly from a broader population-based perspective. METHODS: A total of 3722 patients admitted with acute HF to 11 greater Worcester (Massachusetts, USA) hospitals during 1995 and 2000 were categorized as being lean (n = 216), normal weight (n = 1465), overweight (n = 1007), or obese (n = 1034) at the time of hospitalization. RESULTS: Obese patients with decompensated HF were significantly younger (mean age = …


Erroneous Measurement Of Intracranial Pressure Caused By Simultaneous Ventricular Drainage: A Hydrodynamic Model Study, H. Wilkinson, Jorge Yarzebski, E. Wilkinson, Frederick Anderson Jul 2010

Erroneous Measurement Of Intracranial Pressure Caused By Simultaneous Ventricular Drainage: A Hydrodynamic Model Study, H. Wilkinson, Jorge Yarzebski, E. Wilkinson, Frederick Anderson

Jorge L. Yarzebski

Intracranial pressure (ICP) is often measured from intraventricular catheters, a technique that allows therapeutic drainage of ventricular cerebrospinal fluid (CSF) as an aid in controlling ICP and circumventing obstruction. Drainage of CSF simultaneously with ongoing ICP measurement has been advocated as safe and efficient, and devices are commercially available to permit this practice; however, this concept has been seriously challenged, based on clinical observations. The inaccuracy induced by simultaneous CSF drainage and ICP monitoring is quantitated in this report in a mechanical brain model using a standard ventricular catheter. The following conclusions have been confirmed: 1) rapid CSF drainage induces …


T2 And T3 Sympathetic Ganglia In The Adult Human: A Cadaver And Clinical-Radiographic Study And Its Clinical Application, Jorge Yarzebski, H. Wilkinson Jul 2010

T2 And T3 Sympathetic Ganglia In The Adult Human: A Cadaver And Clinical-Radiographic Study And Its Clinical Application, Jorge Yarzebski, H. Wilkinson

Jorge L. Yarzebski

The technique of percutaneous radiofrequency (RF) upper thoracic sympathectomy mandates an exact knowledge of the anatomical location of the sympathetic ganglia. Because conflicting descriptions are given in anatomy texts, we examined the T2 and T3 sympathetic ganglia in 48 sympathetic chains in adult cadavers to measure the exact location of the ganglia. Measurements were made relative to their distances (a) dorsal to the ventral surface of the vertebral body and (b) rostral or caudal to the midpoint of the vertebral body. Median locations of T2 and T3 ganglia were 17 to 20 mm dorsal to the ventral surface of the …


Dosimetric Evaluation Of Helical Tomotherapy Treatment Planning For Non-Small Cell Lung Cancer, Karen Chu, George Rodrigues, Slav Yartsev, A. Rashid Dar, Edward Yu, Robert Ash, Brian Yaremko, Marc Mackenzie, Harvey Quon, Glenn Bauman, Wilson Roa Dec 2007

Dosimetric Evaluation Of Helical Tomotherapy Treatment Planning For Non-Small Cell Lung Cancer, Karen Chu, George Rodrigues, Slav Yartsev, A. Rashid Dar, Edward Yu, Robert Ash, Brian Yaremko, Marc Mackenzie, Harvey Quon, Glenn Bauman, Wilson Roa

Edward Yu

Helical tomotherapy (HT) is a novel technique to deliver intensity modulated radiation therapy guided by 3D megavoltage CT imaging. The purpose of our study is to assess the dosimetric parameters related to HT and 3DCRT in advanced non-small cell lung cancer (NSCLC). Eleven patients from the London Regional Cancer Centre and the Cross Cancer Institute with NSCLC underwent individualized treatment planning on both HT and 3DCRT. Corresponding HT and 3DCRT plans for each patient were analyzed using dose-volume histograms for GTV, PTV (median dose 60Gy/30 fractions), and critical structures (lung V5-30, esophageal V50-60, and spinal cord D1). Observed differences in …


Prediction Of Radiation Pneumonitis By Dose-Volume Histogram Parameters In Lung Cancer--A Systematic Review, George Rodrigues, Michael Lock, David D'Souza, Edward Yu, Jake Van Dyk Apr 2004

Prediction Of Radiation Pneumonitis By Dose-Volume Histogram Parameters In Lung Cancer--A Systematic Review, George Rodrigues, Michael Lock, David D'Souza, Edward Yu, Jake Van Dyk

Edward Yu

BACKGROUND AND PURPOSE: To perform a systematic review of the predictive ability of various dose-volume histogram (DVH) parameters (V(dose), mean lung dose (MLD), and normal tissue complication probability (NTCP)) in the incidence of radiation pneumonitis (RP) caused by external-beam radiation therapy. METHODS AND MATERIALS: Studies assessing the relationship between CT-based DVH reduction parameters and RP rate in radically treated lung cancer were eligible for the review. Synonyms for RP, lung cancer, DVH and its associated parameters (NTCP, V(20), V(30), MLD) were combined in a search strategy involving electronic databases, secondary reference searching, and consultation with experts. Individual or group data …