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https://www.readbyqxmd.com/read/29133282/effectiveness-of-a-web-2-0-intervention-to-increase-physical-activity-in-real-world-settings-randomized-ecological-trial
#1
Corneel Vandelanotte, Gregory S Kolt, Cristina M Caperchione, Trevor N Savage, Richard R Rosenkranz, Anthony J Maeder, Anetta Van Itallie, Rhys Tague, Christopher Oldmeadow, W Kerry Mummery, Mitch J Duncan
BACKGROUND: The translation of Web-based physical activity intervention research into the real world is lacking and becoming increasingly important. OBJECTIVE: To compare usage and effectiveness, in real-world settings, of a traditional Web 1.0 Web-based physical activity intervention, providing limited interactivity, to a Web 2.0 Web-based physical activity intervention that includes interactive features, such as social networking (ie, status updates, online "friends," and personalized profile pages), blogs, and Google Maps mash-ups...
November 13, 2017: Journal of Medical Internet Research
https://www.readbyqxmd.com/read/29127621/how-well-is-the-medical-home-working-for-latino-and-black-children
#2
Alma D Guerrero, Xinkai Zhou, Paul J Chung
Objective To examine the benefits of having a medical home among Latino and Black school-aged children, both with and without special health care needs (CSHCN). Methods Data from the 2011-2012 National Survey of Children's Health (NSCH) were analyzed to examine the associations of preventive dental and medical care, unmet dental or medical care, or missed school days with having a medical home among Latino and Black children compared to White children. Multivariate logistic regression with survey weights was used to adjust for child, parent, home, and geographic characteristics and an interaction term to estimate differences in outcomes among Black or Latino children receiving care in a medical home compared to White children with a medical home...
November 10, 2017: Maternal and Child Health Journal
https://www.readbyqxmd.com/read/29118795/cost-analysis-of-the-addition-of-hyperacute-magnetic-resonance-imaging-for-selection-of-patients-for-endovascular-stroke-therapy
#3
Seby John, Nicolas R Thompson, Terry Lesko, Nancy Papesh, Nancy Obuchowski, Dan Tomic, Dolora Wisco, Zeshaun Khawaja, Ken Uchino, Shumei Man, Esteban Cheng-Ching, Gabor Toth, Thomas Masaryk, Paul Ruggieri, Michael Modic, Muhammad Shazam Hussain
Background and Purpose: Patient selection is important to determine the best candidates for endovascular stroke therapy. In application of a hyperacute magnetic resonance imaging (MRI) protocol for patient selection, we have shown decreased utilization with improved outcomes. A cost analysis comparing the pre- and post-MRI protocol time periods was performed to determine if the previous findings translated into cost opportunities. Materials and Methods: We retrospectively identified individuals considered for endovascular stroke therapy from January 2008 to August 2012 who were ≤8 h from stroke symptoms onset...
October 2017: Interventional Neurology
https://www.readbyqxmd.com/read/29108137/multi-arm-trials-with-multiple-primary-endpoints-and-missing-values
#4
Mario Hasler, Ludwig A Hothorn
We present an extension of multiple contrast tests for multiple endpoints to the case of missing values. The endpoints are assumed to be normally distributed and correlated and to have equal covariance matrices for the different treatments. Different multivariate t distributions will be applied, differing in endpoint-specific degrees of freedom. In contrast to competing methods, the familywise error type I is maintained in the strong sense in an admissible range, and the problem of different marginal errors type I is avoided...
November 6, 2017: Statistics in Medicine
https://www.readbyqxmd.com/read/29097879/predicting-disease-risk-by-transformation-models-in-the-presence-of-unspecified-subgroup-membership
#5
Qianqian Wang, Yanyuan Ma, Yuanjia Wang
Some biomedical studies lead to mixture data. When a discrete covariate defining subgroup membership is missing for some of the subjects in a study, the distribution of the outcome follows a mixture distribution of the subgroup-specific distributions. Taking into account the uncertain distribution of the group membership and the covariates, we model the relation between the disease onset time and the covariates through transformation models in each sub-population, and develop a nonparametric maximum likelihood based estimation implemented through EM algorithm along with its inference procedure...
October 2017: Statistica Sinica
https://www.readbyqxmd.com/read/29091198/cd4-cell-count-response-to-first-line-combination-art-in-hiv-2-patients-compared-with-hiv-1-patients-a-multinational-multicohort-european-study
#6
Linda Wittkop, Julie Arsandaux, Ana Trevino, Maarten Schim van der Loeff, Jane Anderson, Ard van Sighem, Jürg Böni, Françoise Brun-Vezinet, Vicente Soriano, Faroudy Boufassa, Norbert Brockmeyer, Alexandra Calmy, François Dabis, Inma Jarrin, Maria Dorrucci, Vitor Duque, Gerd Fätkenheuer, Robert Zangerle, Elena Ferrer, Kholoud Porter, Ali Judd, Nikolaos V Sipsas, Olivier Lambotte, Leah Shepherd, Catherine Leport, Charles Morrison, Cristina Mussini, Niels Obel, Jean Ruelle, Carolyne Schwarze-Zander, Anders Sonnerborg, Ramon Teira, Carlo Torti, Emilia Valadas, Celine Colin, Nina Friis-Møller, Dominique Costagliola, Rodolphe Thiebaut, Geneviève Chene, Sophie Matheron
Background: CD4 cell recovery following first-line combination ART (cART) is poorer in HIV-2+ than in HIV-1+ patients. Only large comparisons may allow adjustments for demographic and pretreatment plasma viral load (pVL). Methods: ART-naive HIV+ adults from two European multicohort collaborations, COHERE (HIV-1 alone) and ACHIeV2e (HIV-2 alone), were included, if they started first-line cART (without NNRTIs or fusion inhibitors) between 1997 and 2011. Patients without at least one CD4 cell count before start of cART, without a pretreatment pVL and with missing a priori-defined covariables were excluded...
October 1, 2017: Journal of Antimicrobial Chemotherapy
https://www.readbyqxmd.com/read/29081743/the-propagation-of-movement-variability-in-time-a-methodological-approach-for-discrete-movements-with-multiple-degrees-of-freedom
#7
Melanie Krüger, Andreas Straube, Thomas Eggert
In recent years, theory-building in motor neuroscience and our understanding of the synergistic control of the redundant human motor system has significantly profited from the emergence of a range of different mathematical approaches to analyze the structure of movement variability. Approaches such as the Uncontrolled Manifold method or the Noise-Tolerance-Covariance decomposition method allow to detect and interpret changes in movement coordination due to e.g., learning, external task constraints or disease, by analyzing the structure of within-subject, inter-trial movement variability...
2017: Frontiers in Computational Neuroscience
https://www.readbyqxmd.com/read/29069967/bayesian-imputation-of-time-varying-covariates-in-linear-mixed-models
#8
Nicole S Erler, Dimitris Rizopoulos, Vincent Wv Jaddoe, Oscar H Franco, Emmanuel Meh Lesaffre
Studies involving large observational datasets commonly face the challenge of dealing with multiple missing values. The most popular approach to overcome this challenge, multiple imputation using chained equations, however, has been shown to be sub-optimal in complex settings, specifically in settings with longitudinal outcomes, which cannot be easily and adequately included in the imputation models. Bayesian methods avoid this difficulty by specification of a joint distribution and thus offer an alternative...
January 1, 2017: Statistical Methods in Medical Research
https://www.readbyqxmd.com/read/29067429/association-of-prehospital-blood-product-transfusion-during-medical-evacuation-of-combat-casualties-in-afghanistan-with-acute-and-30-day-survival
#9
Stacy A Shackelford, Deborah J Del Junco, Nicole Powell-Dunford, Edward L Mazuchowski, Jeffrey T Howard, Russ S Kotwal, Jennifer Gurney, Frank K Butler, Kirby Gross, Zsolt T Stockinger
Importance: Prehospital blood product transfusion in trauma care remains controversial due to poor-quality evidence and cost. Sequential expansion of blood transfusion capability after 2012 to deployed military medical evacuation (MEDEVAC) units enabled a concurrent cohort study to focus on the timing as well as the location of the initial transfusion. Objective: To examine the association of prehospital transfusion and time to initial transfusion with injury survival...
October 24, 2017: JAMA: the Journal of the American Medical Association
https://www.readbyqxmd.com/read/29064910/a-molecular-pathway-analysis-informs-the-genetic-risk-for-arrhythmias-during-antipsychotic-treatment
#10
Ellen Kure Fischer, Antonio Drago
Arrhythmias are a frequent and potentially fatal side effect of antipsychotic treatment. Strict ECG monitoring and clinical interviews are the standards used to prevent arrhythmias. A biologic predictive tool is missing. The identification of a genetic makeup at risk of antipsychotic-induced arrhythmias is the aim of the present investigation. The aim of this study was to identify a molecular pathway enriched in single nucleotide polymorphisms associated with antipsychotic-induced QTc modifications. In total, 661 schizophrenic individuals from the CATIE study, M=486 (73...
October 23, 2017: International Clinical Psychopharmacology
https://www.readbyqxmd.com/read/29064477/earlier-bmi-rebound-and-lower-pre-rebound-bmi-as-risk-of-obesity-among-japanese-preschool-children
#11
N Kato, T Isojima, S Yokoya, T Tanaka, A Ono, H Yokomichi, Z Yamagata, S Tanaka, H Matsubara, M Ishikuro, M Kikuya, S Chida, M Hosoya, S Kuriyama, S Kure
OBJECTIVES: Longitudinal growth data of children were analyzed to clarify the relationship between the timing of body mass index (BMI) rebound and obesity risk in later ages. SUBJECTS/METHODS: Of 54 558 children born between April 2004 and March 2005 and longitudinally measured in April and October every year in the preschool period, 15 255 children were analyzed wherein no longitudinal measurement is missing after 1 year of age. BMI rebound age was determined as the age with smallest BMI value across longitudinal individual data after 1 year of age...
October 3, 2017: International Journal of Obesity: Journal of the International Association for the Study of Obesity
https://www.readbyqxmd.com/read/29058049/bayesian-estimation-and-use-of-high-throughput-remote-sensing-indices-for-quantitative-genetic-analyses-of-leaf-growth
#12
Robert L Baker, Wen Fung Leong, Nan An, Marcus T Brock, Matthew J Rubin, Stephen Welch, Cynthia Weinig
We develop Bayesian function-valued trait models that mathematically isolate genetic mechanisms underlying leaf growth trajectories by factoring out genotype-specific differences in photosynthesis. Remote sensing data can be used instead of leaf-level physiological measurements. Characterizing the genetic basis of traits that vary during ontogeny and affect plant performance is a major goal in evolutionary biology and agronomy. Describing genetic programs that specifically regulate morphological traits can be complicated by genotypic differences in physiological traits...
October 20, 2017: TAG. Theoretical and Applied Genetics. Theoretische und Angewandte Genetik
https://www.readbyqxmd.com/read/29048993/personalized-risk-prediction-in-clinical-oncology-research-applications-and-practical-issues-using-survival-trees-and-random-forests
#13
Chen Hu, Jon Arni Steingrimsson
A crucial component of making individualized treatment decisions is to accurately predict each patient's disease risk. In clinical oncology, disease risks are often measured through time-to-event data, such as overall survival and progression/recurrence-free survival, and are often subject to censoring. Risk prediction models based on recursive partitioning methods are becoming increasingly popular largely due to their ability to handle nonlinear relationships, higher-order interactions, and/or high-dimensional covariates...
October 19, 2017: Journal of Biopharmaceutical Statistics
https://www.readbyqxmd.com/read/29040396/survival-analysis-with-time-dependent-covariates-subject-to-missing-data-or-measurement-error-multiple-imputation-for-joint-modeling-mijm
#14
Margarita Moreno-Betancur, John B Carlin, Samuel L Brilleman, Stephanie K Tanamas, Anna Peeters, Rory Wolfe
Modern epidemiological studies collect data on time-varying individual-specific characteristics, such as body mass index and blood pressure. Incorporation of such time-dependent covariates in time-to-event models is of great interest, but raises some challenges. Of specific concern are measurement error, and the non-synchronous updating of covariates across individuals, due for example to missing data. It is well known that in the presence of either of these issues the last observation carried forward (LOCF) approach traditionally used leads to bias...
October 12, 2017: Biostatistics
https://www.readbyqxmd.com/read/29023246/effect-of-various-durations-of-smoking-cessation-on-postoperative-outcomes-a-retrospective-cohort-analysis
#15
Alparslan Turan, Onur Koyuncu, Cameron Egan, Jing You, Kurt Ruetzler, Daniel I Sessler, Jacek B Cywinski
BACKGROUND: Preoperative smoking cessation is commonly advised in an effort to improve postoperative outcomes. However, it remains unclear for how long smoking cessation is necessary, and even whether a brief preoperative period of abstinence is helpful and well tolerated. OBJECTIVE: We evaluated associations between various periods of preoperative smoking cessation and major morbidity and death. DESIGN: Retrospective cohort analysis. SETTING: Adults who had noncardiac surgery at the Cleveland Clinic Main Campus between May 2007 and December 2013...
October 11, 2017: European Journal of Anaesthesiology
https://www.readbyqxmd.com/read/29020025/worry-about-racial-discrimination-a-missing-piece-of-the-puzzle-of-black-white-disparities-in-preterm-birth
#16
Paula Braveman, Katherine Heck, Susan Egerter, Tyan Parker Dominguez, Christine Rinki, Kristen S Marchi, Michael Curtis
OBJECTIVES: The causes of the large and persistent Black-White disparity in preterm birth (PTB) are unknown. It is biologically plausible that chronic stress across a woman's life course could be a contributor. Prior research suggests that chronic worry about experiencing racial discrimination could affect PTB through neuroendocrine, vascular, or immune mechanisms involved in both responses to stress and the initiation of labor. This study aimed to examine the role of chronic worry about racial discrimination in Black-White disparities in PTB...
2017: PloS One
https://www.readbyqxmd.com/read/29019805/do-obese-and-extremely-obese-patients-lose-weight-after-lumbar-spine-fusions-analysis-of-a-cohort-of-7303-patients-from-the-kaiser-national-spine-registry
#17
Paul T Akins, Maria Cs Inacio, Johannas A Bernbeck, Jessica Harris, Yuexin X Chen, Heather A Prentice, Kern H Guppy
STUDY DESIGN: A retrospective cohort study from the Kaiser Permanente Spine Registry OBJECTIVE.: Determine whether obese and extremely obese patients with lumbar spine fusions lost a clinically significant amount of weight (> 5%) 1 year after their surgery SUMMARY OF BACKGROUND DATA.: Obesity in the United States has a prevalence of 35% and is a global health issue. Obesity is associated with lumbar spine disease. There is limited evidence regarding post-surgical weight loss after spine surgery...
October 10, 2017: Spine
https://www.readbyqxmd.com/read/29018369/a-solution-to-modeling-multilevel-confirmatory-factor-analysis-with-data-obtained-from-complex-survey-sampling-to-avoid-conflated-parameter-estimates
#18
Jiun-Yu Wu, John J H Lin, Mei-Wen Nian, Yi-Cheng Hsiao
The issue of equality in the between-and within-level structures in Multilevel Confirmatory Factor Analysis (MCFA) models has been influential for obtaining unbiased parameter estimates and statistical inferences. A commonly seen condition is the inequality of factor loadings under equal level-varying structures. With mathematical investigation and Monte Carlo simulation, this study compared the robustness of five statistical models including two model-based (a true and a mis-specified models), one design-based, and two maximum models (two models where the full rank of variance-covariance matrix is estimated in between level and within level, respectively) in analyzing complex survey measurement data with level-varying factor loadings...
2017: Frontiers in Psychology
https://www.readbyqxmd.com/read/29016608/military-service-deployments-and-exposures-in-relation-to-amyotrophic-lateral-sclerosis-survival
#19
John D Beard, Lawrence S Engel, David B Richardson, Marilie D Gammon, Coleen Baird, David M Umbach, Kelli D Allen, Catherine L Stanwyck, Jean Keller, Dale P Sandler, Silke Schmidt, Freya Kamel
BACKGROUND: Military veterans may have higher rates of amyotrophic lateral sclerosis (ALS) mortality than non-veterans. Few studies, with sparse exposure information and mixed results, have studied relationships between military-related factors and ALS survival. We evaluated associations between military-related factors and ALS survival among U.S. military veteran cases. METHODS: We followed 616 medical record-confirmed cases from enrollment (2005-2010) in the Genes and Environmental Exposures in Veterans with Amyotrophic Lateral Sclerosis study until death or July 25, 2013, whichever came first...
2017: PloS One
https://www.readbyqxmd.com/read/28987392/shunt-failure-risk-factors-and-outcomes-an-analysis-of-the-society-of-thoracic-surgeons-congenital-heart-surgery-database
#20
Nhue Do, Kevin D Hill, Amelia S Wallace, Luca Vricella, Duke Cameron, James Quintessenza, Neil Goldenberg, Constantine Mavroudis, Tom Karl, Sara K Pasquali, Jeffrey P Jacobs, Marshall L Jacobs
BACKGROUND: Systemic-to-pulmonary shunt failure is a potentially catastrophic complication. We analyzed a large multicenter clinical registry to describe the prevalence and evaluate risk factors. METHODS: Infants (aged ≤365 days) undergoing shunt operations (systemic artery-to-pulmonary artery or systemic ventricle-to-pulmonary artery) in The Society of Thoracic Surgeons Congenital Heart Surgery Database (STS-CHSD) from 2010 to 2015 were included. Multivariable logistic regression was used to evaluate risk factors for in-hospital shunt failure...
October 4, 2017: Annals of Thoracic Surgery
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