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https://www.readbyqxmd.com/read/27921315/imputing-estrogen-receptor-er-status-in-a-population-based-cancer-registry-a-sensitivity-analysis
#1
Rebecca Andridge, Anne-Michelle Noone, Nadia Howlader
Breast cancers are clinically heterogeneous based on tumor markers. The National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) Program provides baseline data on these tumor markers for reporting cancer burden and trends over time in the US general population. These tumor markers, however, are often prone to missing observations. In particular, estrogen receptor (ER) status, a key biomarker in the study of breast cancer, has been collected since 1992 but historically was not well-reported, with missingness rates as high as 25% in early years...
December 5, 2016: Statistics in Medicine
https://www.readbyqxmd.com/read/27919246/adjacent-sequences-disclose-potential-for-intra-genomic-dispersal-of-satellite-dna-repeats-and-suggest-a-complex-network-with-transposable-elements
#2
Eva Satović, Tanja Vojvoda Zeljko, Andrea Luchetti, Barbara Mantovani, Miroslav Plohl
BACKGROUND: Satellite DNA (satDNA) sequences are typically arranged as arrays of tandemly repeated monomers. Due to the similarity among monomers, their organizational pattern and abundance, satDNAs are hardly accessible to structural and functional studies and still represent the most obscure genome component. Although many satDNA arrays of diverse length and even single monomers exist in the genome, surprisingly little is known about transition from satDNAs to other sequences. Studying satDNA monomers at junctions and identifying DNA sequences adjacent to them can help to understand the processes that (re)distribute satDNAs and significance that evolution of these sequence elements might have in creating the genomic landscape...
December 6, 2016: BMC Genomics
https://www.readbyqxmd.com/read/27915317/initiating-retinopathy-of-prematurity-screening-before-discharge-from-the-neonatal-care-unit-effect-on-enrolment-in-rural-india
#3
Anand Vinekar, Chaitra Jayadev, Shwetha Mangalesh, Mathew Kurian, Mangat Dogra, Noel Bauer, Bhujang Shetty
OBJECTIVE: To compare the benefits of initiating Retinopathy of Prematurity (ROP) screening at first contact with the admitted infant prior to hospital discharge ('early screening') with screening performed between 21 and 28 days after birth ('conventional screening') in rural India. DESIGN: Prospective study. SETTING: Two Level II neonatal intensive care units (NICU), from two district headquarters in Karnataka state. PARTICIPANTS: Participants: 329 infants admitted in the two NICUs...
November 7, 2016: Indian Pediatrics
https://www.readbyqxmd.com/read/27911621/exergaming-for-health-a-randomized-study-of-community-based-exergaming-curriculum-in-pediatric-weight-management
#4
Amy L Christison, Tyler A Evans, Brandon B Bleess, Huaping Wang, Jean C Aldag, Helen J Binns
OBJECTIVE: To evaluate the effectiveness and sustainable impact of a multifaceted community-based weight intervention program for children, including exergaming curriculum. METHODS: Eighty overweight or obese children, aged 8-12 years, were randomly assigned in a 2:1 ratio to an Exergaming for Health intervention group, comprising both exergaming and classroom curriculum, or to a control group with classroom curriculum alone. Outcome measures included body mass index (BMI), z-score change, and shuttle runs to assess cardiorespiratory endurance...
December 2, 2016: Games for Health
https://www.readbyqxmd.com/read/27910217/disentangling-estimands-and-the-intention-to-treat-principle
#5
Ann-Kristin Leuchs, Andreas Brandt, Jörg Zinserling, Norbert Benda
Randomized controlled trials (RCTs) aim at providing reliable estimates of treatment benefit. Missing data and nonadherence to treatment are distinct problems that can substantially impede this task. In practice, the fact that the handling of missing data due to nonadherence affects the question that is addressed is often ignored. Estimands allow precisely predefining the question of interest. Estimands are definitions of that which is being estimated with regard to population, endpoint, and handling of postrandomization events (eg, nonadherence)...
December 2, 2016: Pharmaceutical Statistics
https://www.readbyqxmd.com/read/27900667/should-domperidone-be-used-as-a-galactagogue-possible-safety-implications-for-mother-and-child
#6
Luc M Hondeghem, Noël H Logghe
Domperidone has been used as a galactagogue; however, solid evidence from an adequate sized randomized clinical trial is missing. Optimal dosage, start of treatment, length of treatment and scope of patients who can benefit also remain unknown. Although milk obtained after domperidone administration has not been shown to have untoward effects on newborns, no sufficiently large randomized clinical trial has been done to establish safety. Domperidone has repeatedly been shown to produce sudden cardiac death, starting at 30 mg/day...
November 29, 2016: Drug Safety: An International Journal of Medical Toxicology and Drug Experience
https://www.readbyqxmd.com/read/27900652/mobile-based-mhgap-ig-depression-screening-in-kenya
#7
Christine W Musyimi, Victoria N Mutiso, Zahra R Haji, Erick S Nandoya, David M Ndetei
We aimed to determine the prevalence and determinants of depression using mobile based mental health Global Action Programme Intervention guide (mhGAP-IG) in remote health care settings where most priority mental health problems are managed by non-mental health specialists and evaluate the feasibility of the application. Adult patients were recruited from four rural public health facilities in Kenya using systematic random sampling and screened for depression. There were no missing items since the application prevented saving of data unless all the items were answered...
November 30, 2016: Community Mental Health Journal
https://www.readbyqxmd.com/read/27898706/prediction-of-body-mass-index-using-concurrently-self-reported-or-previously-measured-height-and-weight
#8
Zhaohui Cui, June Stevens, Kimberly P Truesdale, Donglin Zeng, Simone French, Penny Gordon-Larsen
OBJECTIVE: To compare alternative models for the imputation of BMIM (measured weight in kilograms/measured height in meters squared) in a longitudinal study. METHODS: We used data from 11,008 adults examined at wave III (2001-2002) and wave IV (2007-2008) in the National Longitudinal Study of Adolescent to Adult Health. Participants were asked their height and weight before being measured. Equations to predict wave IV BMIM were developed in an 80% random subsample and evaluated in the remaining participants...
2016: PloS One
https://www.readbyqxmd.com/read/27898181/endovenous-ablation-therapy-laser-or-radiofrequency-or-foam-sclerotherapy-versus-conventional-surgical-repair-for-short-saphenous-varicose-veins
#9
REVIEW
Sharath Chandra Vikram Paravastu, Margaret Horne, P Dominic F Dodd
BACKGROUND: Short (or small) saphenous vein (SSV) varices occur as a result of an incompetent sapheno-popliteal junction, where the SSV joins the popliteal vein, resulting in reflux in the SSV; they account for about 15% of varicose veins. Untreated varicose veins may sometimes lead to ulceration of the leg, which is difficult to manage. Traditionally, treatment was restricted to surgery or conservative management. Since the 1990s, however, a number of minimally invasive techniques have been developed; these do not normally require a general anaesthetic, are day-case procedures with a quicker return to normal activities and avoid the risk of wound infection which may occur following surgery...
November 29, 2016: Cochrane Database of Systematic Reviews
https://www.readbyqxmd.com/read/27896976/missing-data-imputation-in-the-electronic-health-record-using-deeply-learned-autoencoders
#10
Brett K Beaulieu-Jones, Jason H Moore
Electronic health records (EHRs) have become a vital source of patient outcome data but the widespread prevalence of missing data presents a major challenge. Different causes of missing data in the EHR data may introduce unintentional bias. Here, we compare the effectiveness of popular multiple imputation strategies with a deeply learned autoencoder using the Pooled Resource Open-Access ALS Clinical Trials Database (PRO-ACT). To evaluate performance, we examined imputation accuracy for known values simulated to be either missing completely at random or missing not at random...
2016: Pacific Symposium on Biocomputing
https://www.readbyqxmd.com/read/27896858/efficacy-and-safety-of-simeprevir-and-sofosbuvir-with-and-without-ribavirin-in-subjects-with-recurrent-genotype-1-hepatitis-c-post-orthotopic-liver-transplant-the-randomized-galaxy-study
#11
Jacqueline G O'Leary, Robert J Fontana, Kimberly Brown, James R Burton, Roberto Firpi-Morell, Andrew Muir, Christopher O'Brien, Mordechai Rabinovitz, K Rajender Reddy, Robert Ryan, Adam Shprecher, Shirley Villadiego, Avinash Prabhakar, Robert S Brown
This prospective, randomized, phase 2 study in subjects with recurrent hepatitis C virus (HCV) genotype 1 post-orthotopic liver transplant evaluated once-daily simeprevir 150mg+sofosbuvir 400mg, with and without ribavirin 1,000mg. Primary endpoint was proportion of subjects with Week 12 sustained virologic response (SVR12). Thirty-three subjects without cirrhosis were randomized 1:1:1 into three arms (stratified by geno/subtype and Q80K): Arm 1, simeprevir+sofosbuvir+ribavirin, 12 weeks; Arm 2, simeprevir+sofosbuvir, 12 weeks; Arm 3, simeprevir+sofosbuvir, 24 weeks; 13 additional subjects (2 with cirrhosis, 11 without cirrhosis) entered Arm 3...
November 29, 2016: Transplant International: Official Journal of the European Society for Organ Transplantation
https://www.readbyqxmd.com/read/27894541/assessment-of-the-changes-in-arch-perimeter-and%C3%A2-irregularity-in-the-mandibular-arch-during-initial-alignment-with-the-acceledent-aura-appliance-vs-no-appliance-in-adolescents-a-single-blind-randomized-clinical-trial
#12
Peter Miles, Elizabeth Fisher
INTRODUCTION: The purpose of this 2-arm parallel trial was to assess the effects of the AcceleDent Aura (OrthoAccel Technologies, Houston, Tex) appliance on the increase in mandibular anterior arch perimeter, the reduction in mandibular arch irregularity, and the amount of discomfort during initial alignment of the mandibular arch with fixed appliances. METHODS: Forty Class II adolescent patients with full fixed appliances and treated with maxillary premolar extractions and no extractions in the mandibular arch participated in this randomized clinical trial...
December 2016: American Journal of Orthodontics and Dentofacial Orthopedics
https://www.readbyqxmd.com/read/27887652/limitations-of-malaria-reactive-case-detection-in-an-area-of-low-and-unstable-transmission-on-the-myanmar-thailand-border
#13
Daniel M Parker, Jordi Landier, Lorenz von Seidlein, Arjen Dondorp, Lisa White, Borimas Hanboonkunupakarn, Richard J Maude, François H Nosten
BACKGROUND: Reactive case detection is an approach that has been proposed as a tool for malaria elimination in low-transmission settings. It is an intuitively justified approach based on the concept of space-time clustering of malaria cases. When an index malaria clinical case is detected, it triggers reactive screening and treatment in the index house and neighbouring houses. However, the efficacy of this approach at varying screening radii and malaria prevalence remains ill defined...
November 25, 2016: Malaria Journal
https://www.readbyqxmd.com/read/27887601/protocol-for-a-prospective-randomized-study-on-neurophysiological-assessment-of-lower-urinary-tract-function-in-a-healthy-cohort
#14
Stéphanie van der Lely, Martina Stefanovic, Melanie R Schmidhalter, Marta Pittavino, Reinhard Furrer, Martina D Liechti, Martin Schubert, Thomas M Kessler, Ulrich Mehnert
BACKGROUND: Lower urinary tract symptoms are highly prevalent and a large proportion of these symptoms are known to be associated with a dysfunction of the afferent pathways. Diagnostic tools for an objective and reproducible assessment of afferent nerve function of the lower urinary tract are missing. Previous studies showed first feasibility results of sensory evoked potential recordings following electrical stimulation of the lower urinary tract in healthy subjects and patients. Nevertheless, a refinement of the methodology is necessary...
November 25, 2016: BMC Urology
https://www.readbyqxmd.com/read/27886712/a-sas-macro-for-the-joint-modeling-of-longitudinal-outcomes-and-multiple-competing-risk-dropouts
#15
Wei Wang, Wanmei Wang, Thomas H Mosley, Michael E Griswold
BACKGROUND AND OBJECTIVES: The joint modeling of longitudinal and survival data to assess effects of multiple informative dropout mechanisms on longitudinal outcomes inference has received considerable attention during recent years; related statistical programs to apply these methods have been lacking. This paper provides a SAS macro implementation of a shared parameter model to accommodate the analysis of longitudinal outcomes in the presence of multiple competing survival/dropout events...
January 2017: Computer Methods and Programs in Biomedicine
https://www.readbyqxmd.com/read/27867254/network-sampling-coverage-ii-the-effect-of-non-random-missing-data-on-network-measurement
#16
Jeffrey A Smith, James Moody, Jonathan Morgan
Missing data is an important, but often ignored, aspect of a network study. Measurement validity is affected by missing data, but the level of bias can be difficult to gauge. Here, we describe the effect of missing data on network measurement across widely different circumstances. In Part I of this study (Smith and Moody, 2013), we explored the effect of measurement bias due to randomly missing nodes. Here, we drop the assumption that data are missing at random: what happens to estimates of key network statistics when central nodes are more/less likely to be missing? We answer this question using a wide range of empirical networks and network measures...
January 2017: Social Networks
https://www.readbyqxmd.com/read/27867251/linear-increments-with-non-monotone-missing-data-and-measurement-error
#17
Shaun R Seaman, Daniel Farewell, Ian R White
Linear increments (LI) are used to analyse repeated outcome data with missing values. Previously, two LI methods have been proposed, one allowing non-monotone missingness but not independent measurement error and one allowing independent measurement error but only monotone missingness. In both, it was suggested that the expected increment could depend on current outcome. We show that LI can allow non-monotone missingness and either independent measurement error of unknown variance or dependence of expected increment on current outcome but not both...
December 2016: Scandinavian Journal of Statistics, Theory and Applications
https://www.readbyqxmd.com/read/27862700/rationale-for-and-design-of-the-true-ahf-trial-the-effects-of-ularitide-on-the-short-term-clinical-course-and-long-term-mortality-of-patients-with-acute-heart-failure
#18
Milton Packer, Richard Holcomb, William T Abraham, Stefan Anker, Kenneth Dickstein, Gerasimos Filippatos, Henry Krum, Aldo P Maggioni, John J V McMurray, Alexandre Mebazaa, Christopher O'Connor, Frank Peacock, Piotr Ponikowski, Frank Ruschitzka, Dirk J van Veldhuisen, Johannes Holzmeister
: The TRUE-AHF is a randomized, double-blind, parallel-group, placebo-controlled trial which is evaluating the effects of a 48-h infusion of ularitide (15 ng/kg/min) on the short- and long-term clinical course of patients with acute heart failure. Noteworthy features of the study include the early enrolment of patients following their initial clinical presentation (within 12 h), and entry blood pressure criteria and thresholds for the adjustment of drug infusion rates, which aim to minimize the risk of hypotension...
November 13, 2016: European Journal of Heart Failure
https://www.readbyqxmd.com/read/27862164/multiple-imputation-in-the-presence-of-non-normal-data
#19
Katherine J Lee, John B Carlin
Multiple imputation (MI) is becoming increasingly popular for handling missing data. Standard approaches for MI assume normality for continuous variables (conditionally on the other variables in the imputation model). However, it is unclear how to impute non-normally distributed continuous variables. Using simulation and a case study, we compared various transformations applied prior to imputation, including a novel non-parametric transformation, to imputation on the raw scale and using predictive mean matching (PMM) when imputing non-normal data...
November 15, 2016: Statistics in Medicine
https://www.readbyqxmd.com/read/27852718/high-intensity-interval-training-versus-moderate-intensity-steady-state-training-in-uk-cardiac-rehabilitation-programmes-hiit-or-miss-uk-study-protocol-for-a-multicentre-randomised-controlled-trial-and-economic-evaluation
#20
Gordon McGregor, Simon Nichols, Thomas Hamborg, Lucy Bryning, Rhiannon Tudor-Edwards, David Markland, Jenny Mercer, Stefan Birkett, Stuart Ennis, Richard Powell, Brian Begg, Mark J Haykowsky, Prithwish Banerjee, Lee Ingle, Rob Shave, Karianne Backx
INTRODUCTION: Current international guidelines for cardiac rehabilitation (CR) advocate moderate-intensity exercise training (MISS, moderate-intensity steady state). This recommendation predates significant advances in medical therapy for coronary heart disease (CHD) and may not be the most appropriate strategy for the 'modern' patient with CHD. High-intensity interval training (HIIT) appears to be a safe and effective alternative, resulting in greater improvements in peak oxygen uptake (VO2 peak)...
November 16, 2016: BMJ Open
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