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https://www.readbyqxmd.com/read/28923700/venous-thromboembolism-risk-in-patients-with-locoregional-urothelial-tract-tumors
#1
Jorge D Ramos, Jonathan T Wingate, Roman Gulati, Elizabeth R Plimack, Lauren C Harshman, Thomas Powles, Simon J Crabb, Guenter Niegisch, Joaquim Bellmunt, Sylvain Ladoire, Ugo De Giorgi, Syed Hussain, Ajjai S Alva, Jack Baniel, Neeraj Agarwal, Jonathan E Rosenberg, Ulka N Vaishampayan, Matthew D Galsky, Evan Y Yu
BACKGROUND: Venous thromboembolism (VTE) is common in cancer patients, but there is limited data on patients with urothelial tract tumors (UTT). We previously identified several associative factors for increased VTE rates in patients with metastatic UTT. In this study, we assessed the frequency, associative factors, and impact on survival of VTE in patients with locoregional UTT. METHODS: Patients with locoregional bladder, upper urinary tract, or urethral cancer were included in this multi-center study from 29 academic institutions...
August 24, 2017: Clinical Genitourinary Cancer
https://www.readbyqxmd.com/read/28910499/joint-model-selection-of-marginal-mean-regression-and-correlation-structure-for-longitudinal-data-with-missing-outcome-and-covariates
#2
Chung-Wei Shen, Yi-Hau Chen
This work develops a joint model selection criterion for simultaneously selecting the marginal mean regression and the correlation/covariance structure in longitudinal data analysis where both the outcome and the covariate variables may be subject to general intermittent patterns of missingness under the missing at random mechanism. The new proposal, termed "joint longitudinal information criterion" (JLIC), is based on the expected quadratic error for assessing model adequacy, and the second-order weighted generalized estimating equation (WGEE) estimation for mean and covariance models...
September 14, 2017: Biometrical Journal. Biometrische Zeitschrift
https://www.readbyqxmd.com/read/28880204/is-the-effect-of-body-mass-index-on-hypertension-modified-by-the-elevation-a-cross-sectional-study-of-rural-areas-in-japan
#3
Tsuyoshi Hamano, Yoshiya Shiotani, Miwako Takeda, Takafumi Abe, Kristina Sundquist, Toru Nabika
Obesity is an established independent risk factor for developing hypertension. A recent study showed that the effect of obesity on hypertension varies by the elevation of the residence area. Thus, we hypothesized that the interaction effect of body mass index (BMI) and elevation has a significant association with hypertension. The first aim of this cross-sectional study was to examine whether BMI was associated with hypertension, after adjustment for covariates. The second aim was to examine whether the interaction term between BMI and elevation was associated with hypertension, after adjustment for covariates...
September 7, 2017: International Journal of Environmental Research and Public Health
https://www.readbyqxmd.com/read/28878928/evaluation-of-a-guided-continuous-quality-improvement-program-in-community-pharmacies
#4
Chanadda Chinthammit, Michael T Rupp, Edward P Armstrong, Tara Modisett, Rebecca P Snead, Terri L Warholak
BACKGROUND: The importance of creating and sustaining a strong culture of patient safety has been recognized as a critical component of safe medication use. This study aims to assess changes in attitudes toward patient safety culture and frequency of quality-related event (QRE) reporting after guided implementation of a continuous quality improvement (CQI) program in a panel of community pharmacies in the United States (U.S.). METHODS: Twenty-one community pharmacies volunteered to participate in the project and were randomly assigned to intervention or control groups...
2017: Journal of Pharmaceutical Policy and Practice
https://www.readbyqxmd.com/read/28868630/a-model-based-conditional-power-assessment-for-decision-making-in-randomized-controlled-trial-studies
#5
Baiming Zou, Jianwen Cai, Gary G Koch, Haibo Zhou, Fei Zou
Conditional power based on summary statistic by comparing outcomes (such as the sample mean) directly between 2 groups is a convenient tool for decision making in randomized controlled trial studies. In this paper, we extend the traditional summary statistic-based conditional power with a general model-based assessment strategy, where the test statistic is based on a regression model. Asymptotic relationships between parameter estimates based on the observed interim data and final unobserved data are established, from which we develop an analytic model-based conditional power assessment for both Gaussian and non-Gaussian data...
September 4, 2017: Statistics in Medicine
https://www.readbyqxmd.com/read/28867223/protein-protein-interaction-site-predictions-with-minimum-covariance-determinant-and-mahalanobis-distance
#6
Zhijun Qiu, Bo Zhou, Jiangfeng Yuan
Protein-protein interaction site (PPIS) prediction must deal with the diversity of interaction sites that limits their prediction accuracy. Use of proteins with unknown or unidentified interactions can also lead to missing interfaces. Such data errors are often brought into the training dataset. In response to these two problems, we used the minimum covariance determinant (MCD) method to refine the training data to build a predictor with better performance, utilizing its ability of removing outliers. In order to predict test data in practice, a method based on Mahalanobis distance was devised to select proper test data as input for the predictor...
September 1, 2017: Journal of Theoretical Biology
https://www.readbyqxmd.com/read/28841080/gains-of-continuing-resuscitation-in-refractory-out-of-hospital-cardiac-arrest-a-model-based-analysis-to-identify-deaths-due-to-intra-arrest-prognostication
#7
Brian Grunau, Joseph Puyat, Hubert Wong, Frank X Scheuermeyer, Joshua C Reynolds, Takahisa Kawano, Joel Singer, William Dick, James Christenson
OBJECTIVE: Prognostication bias, in which a clinician predicts a negative outcome and terminates resuscitation (TR) thereby ensuring a poor outcome, is a rarely identified limitation of out-of-hospital cardiac arrest (OHCA) research. We sought to estimate the number of deaths due to intra-arrest prognostication in a cohort of OHCA's, and use this data to estimate the incremental benefit of continuing resuscitation. METHODS: This study examined a cohort of consecutive non-traumatic EMS-treated OHCAs from a provincial ambulance service, between 2007 and 2011 inclusive...
August 25, 2017: Prehospital Emergency Care
https://www.readbyqxmd.com/read/28840258/individualised-variable-interval-risk-based-screening-for-sight-threatening-diabetic-retinopathy-the-liverpool-risk-calculation-engine
#8
Antonio Eleuteri, Anthony C Fisher, Deborah M Broadbent, Marta García-Fiñana, Christopher P Cheyne, Amu Wang, Irene M Stratton, Mark Gabbay, Daniel Seddon, Simon P Harding
AIMS/HYPOTHESIS: Individualised variable-interval risk-based screening offers better targeting and improved cost-effectiveness in screening for diabetic retinopathy. We developed a generalisable risk calculation engine (RCE) to assign personalised intervals linked to local population characteristics, and explored differences in assignment compared with current practice. METHODS: Data from 5 years of photographic screening and primary care for people with diabetes, screen negative at the first of > 1 episode, were combined in a purpose-built near-real-time warehouse...
August 24, 2017: Diabetologia
https://www.readbyqxmd.com/read/28830466/methods-for-significance-testing-of-categorical-covariates-in-logistic-regression-models-after-multiple-imputation-power-and-applicability-analysis
#9
Iris Eekhout, Mark A van de Wiel, Martijn W Heymans
BACKGROUND: Multiple imputation is a recommended method to handle missing data. For significance testing after multiple imputation, Rubin's Rules (RR) are easily applied to pool parameter estimates. In a logistic regression model, to consider whether a categorical covariate with more than two levels significantly contributes to the model, different methods are available. For example pooling chi-square tests with multiple degrees of freedom, pooling likelihood ratio test statistics, and pooling based on the covariance matrix of the regression model...
August 22, 2017: BMC Medical Research Methodology
https://www.readbyqxmd.com/read/28815032/pain-may-be-an-important-factor-to-consider-in-inflammatory-bowel-disease-patients-troubled-by-fatigue
#10
Lars-Petter Jelsness-Jørgensen, Svein-Oskar Frigstad, Bjørn Moum, Tore Grimstad, Randi Opheim, Jørgen Jahnsen, Tomm Bernklev
BACKGROUND: Pain has been associated with fatigue in many chronic diseases, but data are not available for inflammatory bowel disease (IBD). The aim of this study was to investigate whether fatigue is associated with pain in IBD after adjusting for the relevant covariates. METHODS: Participants were recruited from nine hospitals in the south-eastern and western part of Norway. Socio-demographic variables were self-reported by patients. Disease activity was assessed by disease activity indices and faecal calprotectin...
August 2017: United European Gastroenterology Journal
https://www.readbyqxmd.com/read/28809768/missed-opportunities-for-chlamydia-screening-in-title-x-family-planning-clinics
#11
Sarah Goldenkranz Salomon, Elizabeth Torrone, Wendy Nakatsukasa-Ono, David N Fine
BACKGROUND: Annual chlamydia (CT) screening is recommended for women younger than 25 years, yet less than half of young women seeking health care are screened annually. We analyzed Title X family planning service data from the Northwest United States to assess factors associated with missed opportunities for CT screening. Our primary hypothesis was screening coverage is higher during annual preventive health visits compared to other visit types. Study objectives were: (1) identify gaps in screening coverage by patient demographics, visit characteristics, and clinic measures; and (2) examine the association between visit type and CT screening by controlling for other covariates and stratifying by state...
September 2017: Sexually Transmitted Diseases
https://www.readbyqxmd.com/read/28802694/exposure-to-ambient-particulate-matter-is-associated-with-accelerated-functional-decline-in-idiopathic-pulmonary-fibrosis
#12
Christopher J Winterbottom, Rupal J Shah, Karen C Patterson, Maryl E Kreider, Reynold A Panettieri, Belinda Rivera-Lebron, Wallace T Miller, Leslie A Litzky, Trevor M Penning, Krista Heinlen, Tara Jackson, A Russell Localio, Jason D Christie
BACKGROUND: Idiopathic pulmonary fibrosis (IPF), a progressive disease with an unknown pathogenesis, may be due in part to an abnormal response to injurious stimuli by alveolar epithelial cells. Air pollution and particulate inhalation of matter evoke a wide variety of pulmonary and systemic inflammatory diseases. We therefore hypothesized that increased average ambient particulate matter (PM) concentrations would be associated with an accelerated rate of decline in FVC in IPF. METHODS: We identified a cohort of subjects seen at a single university referral center from 2007 to 2013...
August 9, 2017: Chest
https://www.readbyqxmd.com/read/28794391/labor-factor-barriers-to-seeking-medical-services-among-metropolitan-workers-a-cross-sectional-analysis-by-sex-using-the-j-shine-study
#13
Liying Pei, Satoshi Toyokawa, Yasuki Kobayashi
OBJECTIVES: There is limited evidence on the relationship between labor factors and the decision to refrain from seeking medical services. This study aimed to examine how labor factors are related to medical service access among male and female workers in Tokyo and surrounding areas. METHODS: We used data from 4,385 respondents to the survey in the Japanese Study on Stratification, Health, Income, and Neighborhood (J-SHINE), an ongoing epidemiologic household panel study...
August 8, 2017: Journal of Occupational Health
https://www.readbyqxmd.com/read/28791798/cost-effectiveness-analysis-of-potentially-curative-and-combination-treatments-for-hepatocellular-carcinoma-with-person-level-data-in-a-canadian-setting
#14
Hla-Hla Thein, Wanrudee Isaranuwatchai, Yao Qiao, Kenny Wong, Gonzalo Sapisochin, Kelvin K W Chan, Eric M Yoshida, Craig C Earle
Patients with early-stage hepatocellular carcinoma (HCC) are potential candidates for curative treatments such as radiofrequency ablation (RFA), surgical resection (SR), or liver transplantation (LT), which have demonstrated a significant survival benefit. We aimed to estimate the cost-effectiveness of curative and combination treatment strategies among patients diagnosed with HCC during 2002-2010. This study used Ontario Cancer Registry-linked administrative data to estimate effectiveness and costs (2013 USD) of the treatment strategies from the healthcare payer's perspective...
August 8, 2017: Cancer Medicine
https://www.readbyqxmd.com/read/28768841/association-of-parathyroid-hormone-with-20-year-cognitive-decline-the-aric-study
#15
MULTICENTER STUDY
Samuel M Kim, Di Zhao, Andrea L C Schneider, Sai Krishna Korada, Pamela L Lutsey, Eliseo Guallar, Alvaro Alonso, B Gwen Windham, Rebecca F Gottesman, Erin D Michos
OBJECTIVE: We hypothesized that elevated parathyroid hormone (PTH) levels will be independently associated with 20-year cognitive decline in a large population-based cohort. METHODS: We studied 12,964 middle-aged white and black ARIC participants without a history of prior stroke who, in 1990-1992 (baseline), had serum PTH levels measured and cognitive function testing, with repeat cognitive testing performed at up to 2 follow-up visits. Cognitive testing included the Delayed Word Recall, the Digit Symbol Substitution, and the Word Fluency tests, which were summed as a global Z score...
August 29, 2017: Neurology
https://www.readbyqxmd.com/read/28764411/adaptive-filtering-for-hidden-node-detection-and-tracking-in-networks
#16
Franz Hamilton, Beverly Setzer, Sergio Chavez, Hien Tran, Alun L Lloyd
The identification of network connectivity from noisy time series is of great interest in the study of network dynamics. This connectivity estimation problem becomes more complicated when we consider the possibility of hidden nodes within the network. These hidden nodes act as unknown drivers on our network and their presence can lead to the identification of false connections, resulting in incorrect network inference. Detecting the parts of the network they are acting on is thus critical. Here, we propose a novel method for hidden node detection based on an adaptive filtering framework with specific application to neuronal networks...
July 2017: Chaos
https://www.readbyqxmd.com/read/28755837/missed-opportunities-for-catch-up-human-papillomavirus-vaccination-among-university-undergraduates-identifying-health-decision-making-behaviors-and-uptake-barriers
#17
Kathleen R Ragan, Robert A Bednarczyk, Scott M Butler, Saad B Omer
BACKGROUND: Suboptimal adolescent human papillomavirus (HPV) vaccine rates in the US highlight the need for catch-up vaccination. When teenagers enter college, there may be a shift in healthcare decision-making from parents and guardians to the students themselves. Little is known about factors influencing college students' healthcare decision-making processes. STUDY DESIGN: We evaluated HPV vaccine decision-making among 18-to-26-year-old college students through a self-administered, anonymous, cross-sectional survey...
July 26, 2017: Vaccine
https://www.readbyqxmd.com/read/28744883/doubly-robust-inference-for-targeted-minimum-loss-based-estimation-in-randomized-trials-with-missing-outcome-data
#18
Iván Díaz, Mark J van der Laan
Missing outcome data is a crucial threat to the validity of treatment effect estimates from randomized trials. The outcome distributions of participants with missing and observed data are often different, which increases bias. Causal inference methods may aid in reducing the bias and improving efficiency by incorporating baseline variables into the analysis. In particular, doubly robust estimators incorporate 2 nuisance parameters: the outcome regression and the missingness mechanism (ie, the probability of missingness conditional on treatment assignment and baseline variables), to adjust for differences in the observed and unobserved groups that can be explained by observed covariates...
July 25, 2017: Statistics in Medicine
https://www.readbyqxmd.com/read/28743256/a-comparison-of-multiple-imputation-methods-for-handling-missing-values-in-longitudinal-data-in-the-presence-of-a-time-varying-covariate-with-a-non-linear-association-with-time-a-simulation-study
#19
Anurika Priyanjali De Silva, Margarita Moreno-Betancur, Alysha Madhu De Livera, Katherine Jane Lee, Julie Anne Simpson
BACKGROUND: Missing data is a common problem in epidemiological studies, and is particularly prominent in longitudinal data, which involve multiple waves of data collection. Traditional multiple imputation (MI) methods (fully conditional specification (FCS) and multivariate normal imputation (MVNI)) treat repeated measurements of the same time-dependent variable as just another 'distinct' variable for imputation and therefore do not make the most of the longitudinal structure of the data...
July 25, 2017: BMC Medical Research Methodology
https://www.readbyqxmd.com/read/28721839/branched-chain-amino-acid-meat-intake-and-risk-of-type-2-diabetes-in-the-women-s-health-initiative
#20
Masoud Isanejad, Andrea Z LaCroix, Cynthia A Thomson, Lesley Tinker, Joseph C Larson, Qibin Qi, Lihong Qi, Rhonda M Cooper-DeHoff, Lawrence S Phillips, Ross L Prentice, Jeannette M Beasley
Knowledge regarding association of dietary branched-chain amino acid (BCAA) and type 2 diabetes (T2D), and the contribution of BCAA from meat to the risk of T2D are scarce. We evaluated associations between dietary BCAA intake, meat intake, interaction between BCAA and meat intake and risk of T2D. Data analyses were performed for 74 155 participants aged 50-79 years at baseline from the Women's Health Initiative for up to 15 years of follow-up. We excluded from analysis participants with treated T2D, and factors potentially associated with T2D or missing covariate data...
June 2017: British Journal of Nutrition
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