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https://www.readbyqxmd.com/read/28633606/exact-bayesian-p-values-for-a-test-of-independence-in-a-2%C3%A2-%C3%A3-%C3%A2-2-contingency-table-with-missing-data
#1
Yan Lin, Stuart R Lipsitz, Debajyoti Sinha, Garrett Fitzmaurice, Steven Lipshultz
Altham (Altham PME. Exact Bayesian analysis of a 2 × 2 contingency table, and Fisher's "exact" significance test. J R Stat Soc B 1969; 31: 261-269) showed that a one-sided p-value from Fisher's exact test of independence in a 2 × 2 contingency table is equal to the posterior probability of negative association in the 2 × 2 contingency table under a Bayesian analysis using an improper prior. We derive an extension of Fisher's exact test p-value in the presence of missing data, assuming the missing data mechanism is ignorable (i...
January 1, 2017: Statistical Methods in Medical Research
https://www.readbyqxmd.com/read/28631331/missing-data-in-clinical-trials-control-based-mean-imputation-and-sensitivity-analysis
#2
Devan V Mehrotra, Fang Liu, Thomas Permutt
In some randomized (drug versus placebo) clinical trials, the estimand of interest is the between-treatment difference in population means of a clinical endpoint that is free from the confounding effects of "rescue" medication (e.g., HbA1c change from baseline at 24 weeks that would be observed without rescue medication regardless of whether or when the assigned treatment was discontinued). In such settings, a missing data problem arises if some patients prematurely discontinue from the trial or initiate rescue medication while in the trial, the latter necessitating the discarding of post-rescue data...
June 20, 2017: Pharmaceutical Statistics
https://www.readbyqxmd.com/read/28629879/prediction-of-cognition-in-parkinson-s-disease-with-a-clinical-genetic-score-a-longitudinal-analysis-of-nine-cohorts
#3
Ganqiang Liu, Joseph J Locascio, Jean-Christophe Corvol, Brendon Boot, Zhixiang Liao, Kara Page, Daly Franco, Kyle Burke, Iris E Jansen, Ana Trisini-Lipsanopoulos, Sophie Winder-Rhodes, Caroline M Tanner, Anthony E Lang, Shirley Eberly, Alexis Elbaz, Alexis Brice, Graziella Mangone, Bernard Ravina, Ira Shoulson, Florence Cormier-Dequaire, Peter Heutink, Jacobus J van Hilten, Roger A Barker, Caroline H Williams-Gray, Johan Marinus, Clemens R Scherzer
BACKGROUND: Cognitive decline is a debilitating manifestation of disease progression in Parkinson's disease. We aimed to develop a clinical-genetic score to predict global cognitive impairment in patients with the disease. METHODS: In this longitudinal analysis, we built a prediction algorithm for global cognitive impairment (defined as Mini Mental State Examination [MMSE] ≤25) using data from nine cohorts of patients with Parkinson's disease from North America and Europe assessed between 1986 and 2016...
June 16, 2017: Lancet Neurology
https://www.readbyqxmd.com/read/28628707/intensive-blood-pressure-reduction-and-spot-sign-in-intracerebral-hemorrhage-a-secondary-analysis-of-a-randomized-clinical-trial
#4
Andrea Morotti, H Bart Brouwers, Javier M Romero, Michael J Jessel, Anastasia Vashkevich, Kristin Schwab, Mohammad Rauf Afzal, Christy Cassarly, Steven M Greenberg, Renee Hebert Martin, Adnan I Qureshi, Jonathan Rosand, Joshua N Goldstein
Importance: The computed tomographic angiography (CTA) spot sign is associated with intracerebral hemorrhage (ICH) expansion and may mark those patients most likely to benefit from intensive blood pressure (BP) reduction. Objective: To investigate whether the spot sign is associated with ICH expansion across a wide range of centers and whether intensive BP reduction decreases hematoma expansion and improves outcome in patients with ICH and a spot sign. Design, Setting, and Participants: SCORE-IT (Spot Sign Score in Restricting ICH Growth) is a preplanned prospective observational study nested in the Antihypertensive Treatment of Acute Cerebral Hemorrhage II (ATACH-II) randomized clinical trial...
June 19, 2017: JAMA Neurology
https://www.readbyqxmd.com/read/28628480/kernel-based-measure-of-variable-importance-for-genetic-association-studies
#5
Vicente Gallego, M Luz Calle, Ramon Oller
The identification of genetic variants that are associated with disease risk is an important goal of genetic association studies. Standard approaches perform univariate analysis where each genetic variant, usually Single Nucleotide Polymorphisms (SNPs), is tested for association with disease status. Though many genetic variants have been identified and validated so far using this univariate approach, for most complex diseases a large part of their genetic component is still unknown, the so called missing heritability...
June 17, 2017: International Journal of Biostatistics
https://www.readbyqxmd.com/read/28628154/-morphological-changes-on-cochlear-hair-cells-of-rats-in-simulated-weightlessness-and-inboard-noise
#6
(no author information available yet)
OBJECTIVE: To observe the morphological changes on cochlear hair cells of rats in simulated weightlessness and inboard noise and to investigate the different changes in three turns of hair cells. METHODS: Thirty-two healthy SD rats, all males, were randomly divided into four groups: control group, weightlessness group, noise group and weightlessness+noise groups (n=8). Then rats were exposed to -30° head down tilt as simulated weightlessness and inboard noise including steady-state noise which was (72±2) dB SPL and impulse noise up to 160 dB SPL in spaceship environment...
June 18, 2017: Beijing da Xue Xue Bao. Yi Xue Ban, Journal of Peking University. Health Sciences
https://www.readbyqxmd.com/read/28624395/statin-trials-cardiovascular-events-and%C3%A2-coronary-artery-calcification-implications-for-a-trial-based-approach-to-statin-therapy-in%C3%A2-mesa
#7
Martin Bødtker Mortensen, Erling Falk, Dong Li, Khurram Nasir, Michael J Blaha, Veit Sandfort, Carlos Jose Rodriguez, Pamela Ouyang, Matthew Budoff
OBJECTIVES: This study sought to determine whether coronary artery calcium (CAC) could be used to optimize statin allocation among individuals for whom trial-based evidence supports efficacy of statin therapy. BACKGROUND: Recently, allocation of statins was proposed for primary prevention of atherosclerotic cardiovascular disease (ASCVD) based on proven efficacy from randomized controlled trials (RCTs) of statin therapy, a so-called trial-based approach. METHODS: The study used data from MESA (Multi-Ethnic Study of Atherosclerosis) with 5,600 men and women, 45 to 84 years of age, and free of clinical ASCVD, lipid-lowering therapy, or missing information for risk factors at baseline examination...
June 9, 2017: JACC. Cardiovascular Imaging
https://www.readbyqxmd.com/read/28624294/patient-decision-aids-for-patients-considering-total-joint-replacement-a-cost-effectiveness-analysis-alongside-a-randomised-controlled-trial
#8
Logan Trenaman, Dawn Stacey, Stirling Bryan, Monica Taljaard, Gillian Hawker, Geoff Dervin, Peter Tugwell, Nick Bansback
BACKGROUND: Shared decision-making (SDM) is a key priority to improve patient-centred care, and can play an important role in helping patients decide whether to undergo total joint arthroplasty (TJA). Patient decision aids can support SDM; however, they may incur an upfront cost. We aimed to estimate the health and economic effects of patient decision aids for TJA. METHODS: A cost-effectiveness analysis of a randomised controlled trial with 2-year follow-up. 343 patients were recruited from two orthopedic screening clinics in Ottawa, Canada...
June 14, 2017: Osteoarthritis and Cartilage
https://www.readbyqxmd.com/read/28623185/a-web-based-data-collection-platform-for-multisite-randomized-behavioral-intervention-trials-development-key-software-features-and-results-of-a-user-survey
#9
Riddhi A Modi, Michael J Mugavero, Rivet K Amico, Jeanne Keruly, Evelyn Byrd Quinlivan, Heidi M Crane, Alfredo Guzman, Anne Zinski, Solange Montue, Katya Roytburd, Anna Church, James H Willig
BACKGROUND: Meticulous tracking of study data must begin early in the study recruitment phase and must account for regulatory compliance, minimize missing data, and provide high information integrity and/or reduction of errors. In behavioral intervention trials, participants typically complete several study procedures at different time points. Among HIV-infected patients, behavioral interventions can favorably affect health outcomes. In order to empower newly diagnosed HIV positive individuals to learn skills to enhance retention in HIV care, we developed the behavioral health intervention Integrating ENGagement and Adherence Goals upon Entry (iENGAGE) funded by the National Institute of Allergy and Infectious Diseases (NIAID), where we deployed an in-clinic behavioral health intervention in 4 urban HIV outpatient clinics in the United States...
June 16, 2017: JMIR Research Protocols
https://www.readbyqxmd.com/read/28622361/prevalence-trend-and-risk-factors-for-antiretroviral-therapy-discontinuation-among-hiv-infected-adults-in-ethiopia-in-2003-2015
#10
Hailay Abrha Gesesew, Paul Ward, Kifle Woldemichael, Lillian Mwanri
BACKGROUND: It is well acknowledged that antiretroviral therapy (ART) discontinuation hampers the progress towards achieving the UNAIDS treatment targets that aim to treat 90% of HIV diagnosed patients and achieve viral suppression for 90% of those on treatment. Nevertheless, the magnitude, trend and risk factors for ART discontinuation have not been explored extensively. We carried out a retrospective data analysis to assess prevalence, trend and risk factors for ART discontinuation among adults in Southwest Ethiopia...
2017: PloS One
https://www.readbyqxmd.com/read/28621925/kpic2-an-effective-framework-for-mass-spectrometry-based-metabolomics-using-pure-ion-chromatograms
#11
Hongchao Ji, Fanjuan Zeng, Yamei Xu, Hongmei Lu, Zhimin Zhang
Distilling accurate quantitation information of metabolites from liquid chromatography coupled with mass spectrometry (LC-MS) datasets is crucial for further statistical analysis and biomarker identification. However, it is still challenging due to the complexity of biological systems. The concept of pure ion chromatograms (PIC) is an effective way for extracting meaningful ions, but few toolboxes provide full processing workflow for LC-MS datasets based on PIC. In this study, an integrated framework, KPIC2, has been developed for metabolomics studies, which can detect pure ions accurately, align PICs across samples, group PICs to identify isotope and potential adducts, fill missing peaks and do multivariate pattern recognition...
June 16, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28616955/niacin-for-primary-and-secondary-prevention-of-cardiovascular-events
#12
REVIEW
Stefan Schandelmaier, Matthias Briel, Ramon Saccilotto, Kelechi K Olu, Armon Arpagaus, Lars G Hemkens, Alain J Nordmann
BACKGROUND: Nicotinic acid (niacin) is known to decrease LDL-cholesterol, and triglycerides, and increase HDL-cholesterol levels. The evidence of benefits with niacin monotherapy or add-on to statin-based therapy is controversial. OBJECTIVES: To assess the effectiveness of niacin therapy versus placebo, administered as monotherapy or add-on to statin-based therapy in people with or at risk of cardiovascular disease (CVD) in terms of mortality, CVD events, and side effects...
June 14, 2017: Cochrane Database of Systematic Reviews
https://www.readbyqxmd.com/read/28615760/use-of-mobile-phone-technology-to-improve-follow-up-at-a-community-mental-health-clinic-a-randomized-control-trial
#13
Gaurav Singh, Narayana Manjunatha, Sabina Rao, H N Shashidhara, Sydney Moirangthem, Rajendra K Madegowda, B Binukumar, Mathew Varghese
BACKGROUND: Mobile phone technology is being used worldwide to improve follow-ups in health care. AIM: Aim of the study is to evaluate whether the use of mobile technology will improve or not the follow-up of Indian patients from a community mental health center. MATERIALS AND METHODS: Patients or caregivers having mobile phones and consenting for study were enrolled, and sociodemographic and clinical details of patients were taken. Participants were randomized into two groups (short message service [SMS] vs...
May 2017: Indian Journal of Psychological Medicine
https://www.readbyqxmd.com/read/28615434/a-randomized-trial-of-telemedicine-efficacy-and-safety-for-nonacute-headaches
#14
Kai I Müller, Karl B Alstadhaug, Svein I Bekkelund
OBJECTIVE: To evaluate long-term treatment efficacy and safety of one-time telemedicine consultations for nonacute headaches. METHODS: We randomized, allocated, and consulted nonacute headache patients via telemedicine (n = 200) or in a traditional manner (n = 202) in a noninferiority trial. Efficacy endpoints, assessed by questionnaires at 3 and 12 months, included change from baseline in Headache Impact Test-6 (HIT-6) (primary endpoint) and pain intensity (visual analogue scale [VAS]) (secondary endpoint)...
June 14, 2017: Neurology
https://www.readbyqxmd.com/read/28614895/endocuff-assisted-vs-standard-colonoscopy-in-the-fecal-occult-blood-test-based-uk-bowel-cancer-screening-programme-e-cap-study-a-randomized-trial
#15
Rupam Bhattacharyya, Fergus Chedgy, Kesavan Kandiah, Carole Fogg, Bernard Higgins, Ben Haysom-Newport, Lisa Gadeke, Fergus Thursby-Pelham, Richard Ellis, Patrick Goggin, Gaius Longcroft-Wheaton, Pradeep Bhandari
Background and study aims Up to 25 % colorectal adenomas are missed during colonoscopy. The aim of this study was to investigate whether the endocuff could improve polyp detection in an organized bowel cancer screening program (BCSP). Patients and methods This parallel group, single-blinded, randomized controlled trial included patients with positive fecal occult blood test (FOBT) who were attending for BCSP colonoscopy. The primary outcome was the number of polyps per patient. Secondary outcomes included the number of adenomas per patient, adenoma and polyp detection rates, and withdrawal times...
June 14, 2017: Endoscopy
https://www.readbyqxmd.com/read/28614357/risk-factors-that-may-be-driving-the-emergence-of-drug-resistance-in-tuberculosis-patients-treated-in-yangon-myanmar
#16
Mishal S Khan, Coll Hutchison, Richard J Coker
BACKGROUND: The majority of new tuberculosis cases emerging every year occur in low and middle-income countries where public health systems are often characterised by weak infrastructure and inadequate resources. This study investigates healthcare seeking behaviour, knowledge and treatment of tuberculosis patients in Myanmar-which is facing an acute drug-resistant tuberculosis epidemic-and identifies factors that may increase the risk of emergence of drug-resistant tuberculosis. METHODS: We randomly selected adult smear-positive pulmonary tuberculosis patients diagnosed between September 2014 and March 2015 at ten public township health centres in Yangon, the largest city in Myanmar...
2017: PloS One
https://www.readbyqxmd.com/read/28613398/fetal-and-umbilical-doppler-ultrasound-in-high-risk-pregnancies
#17
REVIEW
Zarko Alfirevic, Tamara Stampalija, Therese Dowswell
BACKGROUND: Abnormal blood flow patterns in fetal circulation detected by Doppler ultrasound may indicate poor fetal prognosis. It is also possible that false positive Doppler ultrasound findings could lead to adverse outcomes from unnecessary interventions, including preterm delivery. OBJECTIVES: The objective of this review was to assess the effects of Doppler ultrasound used to assess fetal well-being in high-risk pregnancies on obstetric care and fetal outcomes...
June 13, 2017: Cochrane Database of Systematic Reviews
https://www.readbyqxmd.com/read/28613202/-comparison-of-two-on-line-risk-calculators-versus-the-detection-of-circulating-prostate-cells-for-the-detection-of-high-risk-prostate-cancer-at-first-biopsy
#18
Nigel P Murray, Cynthia Fuentealba, Eduardo Reyes, Omar Jacob
OBJECTIVE: The limitations of total serum PSA values remains problematic; nomograms may improve the prediction of a positive prostate biopsy (PB). We compare in a prospective study of Chilean men with suspicion of prostate cancer due to an elevated total serum PSA and/or abnormal digital rectal examination, the use of two on-line nomograms with the detection of primary malignant circulating prostate cells (CPCs) to predict a positive PB for high risk prostate cancer. METHODS: Consecutive men with suspicion of prostate cancer underwent 12 core TRUS prostate biopsy...
June 2017: Archivos Españoles de Urología
https://www.readbyqxmd.com/read/28613154/seal-or-varnish-a-randomised-controlled-trial-to-determine-the-relative-cost-and-effectiveness-of-pit-and-fissure-sealant-and-fluoride-varnish-in-preventing-dental-decay
#19
Ivor Gordon Chestnutt, Simon Hutchings, Rebecca Playle, Sarah Morgan-Trimmer, Deborah Fitzsimmons, Nadine Aawar, Lianna Angel, Sharron Derrick, Cheney Drew, Ceri Hoddell, Kerenza Hood, Ioan Humphreys, Nigel Kirby, Tin Man Mandy Lau, Catherine Lisles, Maria Zeta Morgan, Simon Murphy, Jacqueline Nuttall, Kateryna Onishchenko, Ceri Phillips, Timothy Pickles, Charlotte Scoble, Julia Townson, Beverley Withers, Barbara Lesley Chadwick
BACKGROUND: Fissure sealant (FS) and fluoride varnish (FV) have been shown to be effective in preventing dental caries when tested against a no-treatment control. However, the relative clinical effectiveness and cost-effectiveness of these interventions is unknown. OBJECTIVE: To compare the clinical effectiveness and cost-effectiveness of FS and FV in preventing dental caries in first permanent molars (FPMs) in 6- and 7-year-olds and to determine their acceptability...
April 2017: Health Technology Assessment: HTA
https://www.readbyqxmd.com/read/28609532/effect-of-abdominal-ultrasound-on-clinical-care-outcomes-and-resource-use-among-children-with-blunt-torso-trauma-a-randomized-clinical-trial
#20
James F Holmes, Kenneth M Kelley, Sandra L Wootton-Gorges, Garth H Utter, Lisa P Abramson, John S Rose, Daniel J Tancredi, Nathan Kuppermann
Importance: The utility of the focused assessment with sonography for trauma (FAST) examination in children is unknown. Objective: To determine if the FAST examination during initial evaluation of injured children improves clinical care. Design, Setting, and Participants: A randomized clinical trial (April 2012-May 2015) that involved 975 hemodynamically stable children and adolescents younger than 18 years treated for blunt torso trauma at the University of California, Davis Medical Center, a level I trauma center...
June 13, 2017: JAMA: the Journal of the American Medical Association
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