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Among women who experience a recurrence after postmastectomy radiation therapy irradiation is not associated with more aggressive local recurrence or reduced survival.

https://arctichealth.org/en/permalink/ahliterature144754
Source
Breast Cancer Res Treat. 2010 Sep;123(2):597-605
Publication Type
Article
Date
Sep-2010
Author
Wendy A Woodward
Pauline T Truong
Tse-Kuan Yu
Welela Tereffe
Julia Oh
George Perkins
Eric Strom
Funda Meric-Bernstam
Ana-Maria Gonzalez-Angulo
Caroline Speers
Joseph Ragaz
Thomas A Buchholz
Author Affiliation
Department of Radiation Oncology, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA. wwoodward@mdanderson.org
Source
Breast Cancer Res Treat. 2010 Sep;123(2):597-605
Date
Sep-2010
Language
English
Publication Type
Article
Keywords
Adult
Breast Neoplasms - mortality - secondary - therapy
British Columbia
Chemotherapy, Adjuvant
Chi-Square Distribution
Clinical Trials as Topic
Disease-Free Survival
Female
Humans
Kaplan-Meier Estimate
Mastectomy
Middle Aged
Neoplasm Recurrence, Local - etiology - mortality - pathology
Neoplasm Staging
Radiotherapy, Adjuvant - adverse effects - mortality
Retrospective Studies
Risk assessment
Risk factors
Survival Rate
Texas
Time Factors
Treatment Outcome
Abstract
Recent pre-clinical models suggest that radiation can promote tumor aggressiveness. We hypothesized that if this were occurring clinically, locoregional recurrences (LRRs) after postmastectomy radiation therapy (PMRT) would lead to lower survival than LRR after mastectomy alone. This study used two independent datasets to compare survival after LRR in women treated with versus without PMRT. Data from 229 LRR cases among 1,500 patients enrolled on prospective trials at the MD Anderson Cancer Center (MDA), and 66 LRR cases among 318 patients enrolled in the British Columbia Cancer Agency (BCCA) PMRT randomized trial were analyzed. In the MDA non-randomized dataset, 189/1031 had LRR after mastectomy alone and 40/469 had LRR after PMRT. In the randomized BC trial dataset, 52/158 had LRR after mastectomy alone and 14/160 had LRR after PMRT. In both datasets, survival was calculated from the time of LRR to death. Analysis of MDA data shows that in all LRR cases regardless of distant metastasis (DM), 5/10-year OS were 50/34% without PMRT and 27/19% after PMRT (P = 0.006). However, PMRT-treated patients had increased risk factors for DM (advanced T and N stages) and more PMRT-treated patients developed DM prior to LRR (63 vs. 34%, P = 0.005). Analyzing only patients will an isolated LRR (without previous or simultaneous, DMV), there was no OS difference between groups (P = 0.33). Analysis of BCCA data shows that distributions of T and N stages were similar in patients with LRR after mastectomy alone versus after PMRT. DM free survival after any LRR and after isolated LRR were similar in mastectomy alone versus PMRT-treated patients (P = 0.75, P = 0.26, respectively). Overall survival after any LRR and after isolated LRR were also similar in the two groups (P = 0.93, P = 0.28, respectively). Patients who develop LRR after mastectomy alone have high rates of DM and poor OS but these rates are not affected by the use of PMRT at the time of primary treatment. These data do not support the hypothesis that irradiation promotes biologically aggressive local recurrences.
PubMed ID
20306128 View in PubMed
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Amyotrophic lateral sclerosis mortality rates in Harris County, Texas.

https://arctichealth.org/en/permalink/ahliterature227318
Source
Adv Neurol. 1991;56:239-43
Publication Type
Article
Date
1991
Author
J F Annegers
S H Appel
P. Perkins
J. Lee
Author Affiliation
University of Texas Health Science Center, School of Public Health, Houston 77030.
Source
Adv Neurol. 1991;56:239-43
Date
1991
Language
English
Publication Type
Article
Keywords
Adult
Age Factors
Aged
Amyotrophic Lateral Sclerosis - mortality
Denmark
Female
Finland
France
Humans
Male
Middle Aged
Sex Factors
Texas
PubMed ID
1853760 View in PubMed
Less detail

An updated inhalation unit risk factor for arsenic and inorganic arsenic compounds based on a combined analysis of epidemiology studies.

https://arctichealth.org/en/permalink/ahliterature122457
Source
Regul Toxicol Pharmacol. 2012 Nov;64(2):329-41
Publication Type
Article
Date
Nov-2012
Author
Neeraja K Erraguntla
Robert L Sielken
Ciriaco Valdez-Flores
Roberta L Grant
Author Affiliation
Texas Commission on Environmental Quality, Toxicology Division, P.O. Box 13087, MC-168, Austin, TX 78711-3087, United States. neeraja.erraguntla@tceq.texas.gov
Source
Regul Toxicol Pharmacol. 2012 Nov;64(2):329-41
Date
Nov-2012
Language
English
Publication Type
Article
Keywords
Arsenic - standards - toxicity
Arsenicals - standards
Female
Humans
Inhalation Exposure - adverse effects - standards
Lung Neoplasms - chemically induced - epidemiology
Male
Metallurgy
Montana
Occupational Diseases - chemically induced - epidemiology
Occupational Exposure - adverse effects - standards
Reference Values
Risk assessment
Sweden
Texas
Abstract
The United States Environmental Protection Agency (USEPA) developed an inhalation unit risk factor (URF) of 4.3E-03 per µg/m(3) for arsenic in 1984 for excess lung cancer mortality based on epidemiological studies of workers at two smelters: the Asarco smelter in Tacoma, Washington and the Anaconda smelter in Montana. Since the USEPA assessment, new studies have been published and exposure estimates were updated at the Asarco and Anaconda smelters and additional years of follow-up evaluated. The Texas Commission on Environmental Quality (TCEQ) has developed an inhalation URF for lung cancer mortality from exposures to arsenic and inorganic arsenic compounds based on a newer epidemiology study of Swedish workers and the updates of the Asarco and Anaconda epidemiology studies. Using a combined analysis approach, the TCEQ weighted the individual URFs from these three epidemiology cohort studies, to calculate a final inhalation URF of 1.5E-04 per µg/m(3). In addition, the TCEQ also conducted a sensitivity analysis, in which they calculated a URF based on a type of meta-analysis, and these results compared well with the results of the combined analysis. The no significant concentration level (i.e., air concentration at 1 in 100,000 excess lung cancer mortality) is 0.067µg/m(3). This value will be used to evaluate ambient air monitoring data so the general public in Texas is protected against adverse health effects from chronic exposure to arsenic.
PubMed ID
22813725 View in PubMed
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Application of finite mixture of negative binomial regression models with varying weight parameters for vehicle crash data analysis.

https://arctichealth.org/en/permalink/ahliterature120275
Source
Accid Anal Prev. 2013 Jan;50:1042-51
Publication Type
Article
Date
Jan-2013
Author
Yajie Zou
Yunlong Zhang
Dominique Lord
Author Affiliation
Zachry Department of Civil Engineering, Texas A&M University, 3136 TAMU, College Station, TX 77843-3136, United States. yajiezou@tamu.edu
Source
Accid Anal Prev. 2013 Jan;50:1042-51
Date
Jan-2013
Language
English
Publication Type
Article
Keywords
Accidents, Traffic - statistics & numerical data
Humans
Models, Statistical
Ontario
Rural Population
Texas
Urban Population
Abstract
Recently, a finite mixture of negative binomial (NB) regression models has been proposed to address the unobserved heterogeneity problem in vehicle crash data. This approach can provide useful information about features of the population under study. For a standard finite mixture of regression models, previous studies have used a fixed weight parameter that is applied to the entire dataset. However, various studies suggest modeling the weight parameter as a function of the explanatory variables in the data. The objective of this study is to investigate the differences on the modeling and fitting results between the two-component finite mixture of NB regression models with fixed weight parameters (FMNB-2) and the two-component finite mixture of NB regression models with varying weight parameters (GFMNB-2), and compare the group classification from both models. To accomplish the objective of this study, the FMNB-2 and GFMNB-2 models are applied to two crash datasets. The important findings can be summarized as follows: first, the GFMNB-2 models can provide more reasonable classification results, as well as better statistical fitting performance than the FMNB-2 models; second, the GFMNB-2 models can be used to better reveal the source of dispersion observed in the crash data than the FMNB-2 models. Therefore, it is concluded that in many cases the GFMNB-2 models may be a better alternative to the FMNB-2 models for explaining the heterogeneity and the nature of the dispersion in the crash data.
PubMed ID
23022076 View in PubMed
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Application of the Conway-Maxwell-Poisson generalized linear model for analyzing motor vehicle crashes.

https://arctichealth.org/en/permalink/ahliterature157326
Source
Accid Anal Prev. 2008 May;40(3):1123-34
Publication Type
Article
Date
May-2008
Author
Dominique Lord
Seth D Guikema
Srinivas Reddy Geedipally
Author Affiliation
Zachry Department of Civil Engineering, Texas A&M University, 3136 TAMU, College Station, TX 77843-3136, USA. d-lord@tamu.edu
Source
Accid Anal Prev. 2008 May;40(3):1123-34
Date
May-2008
Language
English
Publication Type
Article
Keywords
Accidents, Traffic - statistics & numerical data
Bayes Theorem
Binomial Distribution
Humans
Likelihood Functions
Linear Models
Models, Statistical
Ontario
Poisson Distribution
Texas
Abstract
This paper documents the application of the Conway-Maxwell-Poisson (COM-Poisson) generalized linear model (GLM) for modeling motor vehicle crashes. The COM-Poisson distribution, originally developed in 1962, has recently been re-introduced by statisticians for analyzing count data subjected to over- and under-dispersion. This innovative distribution is an extension of the Poisson distribution. The objectives of this study were to evaluate the application of the COM-Poisson GLM for analyzing motor vehicle crashes and compare the results with the traditional negative binomial (NB) model. The comparison analysis was carried out using the most common functional forms employed by transportation safety analysts, which link crashes to the entering flows at intersections or on segments. To accomplish the objectives of the study, several NB and COM-Poisson GLMs were developed and compared using two datasets. The first dataset contained crash data collected at signalized four-legged intersections in Toronto, Ont. The second dataset included data collected for rural four-lane divided and undivided highways in Texas. Several methods were used to assess the statistical fit and predictive performance of the models. The results of this study show that COM-Poisson GLMs perform as well as NB models in terms of GOF statistics and predictive performance. Given the fact the COM-Poisson distribution can also handle under-dispersed data (while the NB distribution cannot or has difficulties converging), which have sometimes been observed in crash databases, the COM-Poisson GLM offers a better alternative over the NB model for modeling motor vehicle crashes, especially given the important limitations recently documented in the safety literature about the latter type of model.
PubMed ID
18460381 View in PubMed
Less detail

Asphyxial games or "the choking game": a potentially fatal risk behaviour.

https://arctichealth.org/en/permalink/ahliterature152799
Source
Inj Prev. 2009 Feb;15(1):45-9
Publication Type
Article
Date
Feb-2009
Author
A J Macnab
M. Deevska
F. Gagnon
W G Cannon
T. Andrew
Author Affiliation
Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada. amacnab@cw.bc.ca
Source
Inj Prev. 2009 Feb;15(1):45-9
Date
Feb-2009
Language
English
Publication Type
Article
Keywords
Adolescent
Asphyxia - epidemiology
Child
Female
Humans
Male
Ontario - epidemiology
Recreation
Risk-Taking
Self-Injurious Behavior - epidemiology
Texas - epidemiology
Abstract
To determine the prevalence of knowledge about and participation in asphyxial games, sometimes called "the choking game", and how best to raise awareness of this risk-taking behaviour and provide preventive education.
Questionnaire; collaborative research model; lay advocacy group/university researchers.
8 middle and high schools in Texas (six) and Ontario (two). A recent death from playing the choking game had occurred in one Texas school, and two other fatalities had occurred within the state.
Students in grades 4-12, aged 9-18 years.
None.
Of 2762 surveys distributed, 2504 (90.7%) were completed. The mean (SD) age of the responders was 13.7 (2.2) years. 68% of children had heard about the game, 45% knew somebody who played it, and 6.6% had tried it, 93.9% of those with someone else. Forty percent of children perceived no risk. Information that playing the game could result in death or brain damage was reported as most likely to influence behaviour. The most respected source of a preventive education message was parents for pre-adolescents (43%) or victim/victim's family (36%) for older adolescents.
Knowledge of and participation in self-asphyxial behaviour is not unusual among schoolchildren. The age of the child probably determines the best source (parents or victim/victim's family) of preventive education.
PubMed ID
19190276 View in PubMed
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Assessment of cerebral autoregulation: the quandary of quantification.

https://arctichealth.org/en/permalink/ahliterature122399
Source
Am J Physiol Heart Circ Physiol. 2012 Sep 15;303(6):H658-71
Publication Type
Article
Date
Sep-15-2012
Author
Y C Tzeng
P N Ainslie
W H Cooke
K C Peebles
C K Willie
B A MacRae
J D Smirl
H M Horsman
C A Rickards
Author Affiliation
Cardiovascular Systems Laboratory, University of Otago, Wellington South, New Zealand. shieak.tzeng@otago.ac.nz
Source
Am J Physiol Heart Circ Physiol. 2012 Sep 15;303(6):H658-71
Date
Sep-15-2012
Language
English
Publication Type
Article
Keywords
Adult
Blood Flow Velocity
Blood pressure
British Columbia
Cerebrovascular Circulation
Exercise
Female
Fourier Analysis
Heart rate
Homeostasis
Humans
Hypercapnia - physiopathology
Hypocapnia - physiopathology
Linear Models
Male
Middle Cerebral Artery - physiopathology - ultrasonography
Models, Cardiovascular
New Zealand
Observer Variation
Prospective Studies
Regional Blood Flow
Reproducibility of Results
Respiration
Retrospective Studies
Supine Position
Texas
Tourniquets
Ultrasonography, Doppler, Pulsed
Ultrasonography, Doppler, Transcranial
Young Adult
Abstract
We assessed the convergent validity of commonly applied metrics of cerebral autoregulation (CA) to determine the extent to which the metrics can be used interchangeably. To examine between-subject relationships among low-frequency (LF; 0.07-0.2 Hz) and very-low-frequency (VLF; 0.02-0.07 Hz) transfer function coherence, phase, gain, and normalized gain, we performed retrospective transfer function analysis on spontaneous blood pressure and middle cerebral artery blood velocity recordings from 105 individuals. We characterized the relationships (n = 29) among spontaneous transfer function metrics and the rate of regulation index and autoregulatory index derived from bilateral thigh-cuff deflation tests. In addition, we analyzed data from subjects (n = 29) who underwent a repeated squat-to-stand protocol to determine the relationships between transfer function metrics during forced blood pressure fluctuations. Finally, data from subjects (n = 16) who underwent step changes in end-tidal P(CO2) (P(ET)(CO2) were analyzed to determine whether transfer function metrics could reliably track the modulation of CA within individuals. CA metrics were generally unrelated or showed only weak to moderate correlations. Changes in P(ET)(CO2) were positively related to coherence [LF: ß = 0.0065 arbitrary units (AU)/mmHg and VLF: ß = 0.011 AU/mmHg, both P
PubMed ID
22821992 View in PubMed
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Attitudes towards war, killing, and punishment of children among young people in Estonia, Finland, Romania, the Russian Federation, and the USA.

https://arctichealth.org/en/permalink/ahliterature194294
Source
Bull World Health Organ. 2001;79(5):382-7
Publication Type
Article
Date
2001
Author
A. McAlister
P. Sandström
P. Puska
A. Veijo
R. Chereches
L T Heidmets
Author Affiliation
University of Texas (Houston) School of Public Health, Houston, TX, USA.
Source
Bull World Health Organ. 2001;79(5):382-7
Date
2001
Language
English
Publication Type
Article
Keywords
Adolescent
Adult
Attitude
Child
Child Rearing - psychology
Cross-Cultural Comparison
Estonia
Female
Finland
Homicide - psychology
Humans
Male
Punishment
Questionnaires
Romania
Russia
Texas
Violence - psychology
War
Abstract
To study the cultural differences in moral disengagement, which lends support to attitudes used to justify violence.
We carried out classroom surveys of a total of 3122 students in the USA (Houston, TX, and Washington, DC) and in four European countries--Estonia (Tartu), Finland (Helsinki), Romania (Satu Mare) and the Russian Federation (St Petersburg). Data were also taken from a random sample telephone survey of 341 young adults (aged 18-35 years) in Texas, USA. Ten distinct groups were studied. Seven questions were common to all the surveys, using identical statements about the participants' agreement with attitudes relating to war, diplomacy, killing, and the punishment of children.
The US students were more likely than those in Europe to agree with the following statements: "War is necessary" (20% vs 9%), "A person has the right to kill to defend property" (54% vs 17%), and "Physical punishment is necessary for children" (27% vs 10%). Justification of war and killing was less common among females than males in all groups; other differences within the US groups and the European groups were smaller than the differences between the US and European groups.
The results confirm the gap between the US and European groups in moral disengagement attitudes and tendencies that could lead to deadly violence.
PubMed ID
11417032 View in PubMed
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Bayesian ranking of sites for engineering safety improvements: decision parameter, treatability concept, statistical criterion, and spatial dependence.

https://arctichealth.org/en/permalink/ahliterature174350
Source
Accid Anal Prev. 2005 Jul;37(4):699-720
Publication Type
Article
Date
Jul-2005
Author
Shaw-Pin Miaou
Joon Jin Song
Author Affiliation
Texas Transportation Institute, Texas A&M University System, 3135 TAMU, College Station, TX 77843-3135, USA. s-miaou@tamu.edu
Source
Accid Anal Prev. 2005 Jul;37(4):699-720
Date
Jul-2005
Language
English
Publication Type
Article
Keywords
Accidents, Traffic - prevention & control - statistics & numerical data
Bayes Theorem
Decision Support Techniques
Human Engineering - methods
Humans
Models, Statistical
Multivariate Analysis
Ontario
Poisson Distribution
Regression Analysis
Risk Assessment - methods
Safety - statistics & numerical data
Texas
Abstract
In recent years, there has been a renewed interest in applying statistical ranking criteria to identify sites on a road network, which potentially present high traffic crash risks or are over-represented in certain type of crashes, for further engineering evaluation and safety improvement. This requires that good estimates of ranks of crash risks be obtained at individual intersections or road segments, or some analysis zones. The nature of this site ranking problem in roadway safety is related to two well-established statistical problems known as the small area (or domain) estimation problem and the disease mapping problem. The former arises in the context of providing estimates using sample survey data for a small geographical area or a small socio-demographic group in a large area, while the latter stems from estimating rare disease incidences for typically small geographical areas. The statistical problem is such that direct estimates of certain parameters associated with a site (or a group of sites) with adequate precision cannot be produced, due to a small available sample size, the rareness of the event of interest, and/or a small exposed population or sub-population in question. Model based approaches have offered several advantages to these estimation problems, including increased precision by "borrowing strengths" across the various sites based on available auxiliary variables, including their relative locations in space. Within the model based approach, generalized linear mixed models (GLMM) have played key roles in addressing these problems for many years. The objective of the study, on which this paper is based, was to explore some of the issues raised in recent roadway safety studies regarding ranking methodologies in light of the recent statistical development in space-time GLMM. First, general ranking approaches are reviewed, which include naïve or raw crash-risk ranking, scan based ranking, and model based ranking. Through simulations, the limitation of using the naïve approach in ranking is illustrated. Second, following the model based approach, the choice of decision parameters and consideration of treatability are discussed. Third, several statistical ranking criteria that have been used in biomedical, health, and other scientific studies are presented from a Bayesian perspective. Their applications in roadway safety are then demonstrated using two data sets: one for individual urban intersections and one for rural two-lane roads at the county level. As part of the demonstration, it is shown how multivariate spatial GLMM can be used to model traffic crashes of several injury severity types simultaneously and how the model can be used within a Bayesian framework to rank sites by crash cost per vehicle-mile traveled (instead of by crash frequency rate). Finally, the significant impact of spatial effects on the overall model goodness-of-fit and site ranking performances are discussed for the two data sets examined. The paper is concluded with a discussion on possible directions in which the study can be extended.
PubMed ID
15949462 View in PubMed
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The case of Samuel Golubchuk: the dangers of judicial deference and medical self-regulation.

https://arctichealth.org/en/permalink/ahliterature144874
Source
Am J Bioeth. 2010 Mar;10(3):59-61
Publication Type
Article
Date
Mar-2010

78 records – page 1 of 8.