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https://www.readbyqxmd.com/read/28426258/improvements-in-out-of-hospital-cardiac-arrest-survival-from-1998-to-2013
#1
Yutaka Yamaguchi, Jeff A Woodin, Koichiro Gibo, Dana M Zive, Mohamud R Daya
OBJECTIVES: Out-of-hospital cardiac arrest (OHCA) remains a major public health burden. Aggregate OHCA survival to hospital discharge has reportedly remained unchanged at 7.6% for almost 30 years from 1970 to 2008. We examined the trends in adult OHCA survival over a 16-year period from 1998 to 2013 within a single EMS agency. METHODS: Observational cohort study of adult OHCA patients treated by Tualatin Valley Fire & Rescue (TVF&R) from 1998 to 2013. This is an ALS first response fire agency that maintains an active Utstein style cardiac arrest registry and serves a population of approximately 450,000 in 9 incorporated cities in Oregon...
April 20, 2017: Prehospital Emergency Care
https://www.readbyqxmd.com/read/28417689/a-bayesian-hierarchical-model-for-discrete-choice-data-in-health-care
#2
Anna Liza M Antonio, Robert E Weiss, Christopher S Saigal, Ely Dahan, Catherine M Crespi
In discrete choice experiments, patients are presented with sets of health states described by various attributes and asked to make choices from among them. Discrete choice experiments allow health care researchers to study the preferences of individual patients by eliciting trade-offs between different aspects of health-related quality of life. However, many discrete choice experiments yield data with incomplete ranking information and sparsity due to the limited number of choice sets presented to each patient, making it challenging to estimate patient preferences...
January 1, 2017: Statistical Methods in Medical Research
https://www.readbyqxmd.com/read/28404658/association-of-glycemic-variability-in-type-1-diabetes-with-progression-of-microvascular-outcomes-in-the-diabetes-control-and-complications-trial
#3
John M Lachin, Ionut Bebu, Richard M Bergenstal, Rodica Pop-Busui, F John Service, Bernard Zinman, David M Nathan
OBJECTIVE: The Diabetes Control and Complications Trial (DCCT) demonstrated the beneficial effects of intensive versus conventional therapy on the development and progression of microvascular complications of type 1 diabetes. These beneficial effects were almost completely explained by the difference between groups in the levels of HbA1c, which in turn were associated with the risk of these complications. We assessed the association of glucose variability within and between quarterly 7-point glucose profiles with the development and progression of retinopathy, nephropathy, and cardiovascular autonomic neuropathy during the DCCT...
April 12, 2017: Diabetes Care
https://www.readbyqxmd.com/read/28404475/exploring-the-short-term-impact-of-community-water-fluoridation-cessation-on-children-s-dental-caries-a-natural-experiment-in-alberta-canada
#4
L McLaren, S Patterson, S Thawer, P Faris, D McNeil, M L Potestio, L Shwart
OBJECTIVES: Dental caries (tooth decay) is common and can be serious. Dental caries is preventable, and community water fluoridation is one means of prevention. There is limited current research on the implications of fluoridation cessation for children's dental caries. Our objective was to explore the short-term impact of community water fluoridation cessation on children's dental caries, by examining change in caries experience in population-based samples of schoolchildren in two Canadian cities, one that discontinued community water fluoridation and one that retained it...
February 7, 2017: Public Health
https://www.readbyqxmd.com/read/28397352/effects-of-expanding-the-look-back-period-to-all-available-data-in-the-assessment-of-covariates
#5
Sonja S Nakasian, Jeremy A Rassen, Jessica M Franklin
BACKGROUND: A fixed baseline period has been a common covariate assessment approach in pharmacoepidemiological studies from claims but may lead to high levels of covariate misclassification. Simulation studies have recommended expanding the look-back approach to all available data (AAD) for binary indicators of diagnoses, procedures, and medications, but there have been few real data analyses using this approach. OBJECTIVE: The objective of the study is to explore the impact on treatment effect estimates and covariate prevalence of expanding the look-back period within five validated studies in the Aetion system, a rapid cycle analytics platform...
April 11, 2017: Pharmacoepidemiology and Drug Safety
https://www.readbyqxmd.com/read/28393570/tafamidis-delays-disease-progression-in-patients-with-early-stage-transthyretin-familial-amyloid-polyneuropathy-additional-supportive-analyses-from-the-pivotal-trial
#6
Denis Keohane, Jeffrey Schwartz, Balarama Gundapaneni, Michelle Stewart, Leslie Amass
BACKGROUND: Tafamidis, a non-NSAID highly specific transthyretin stabilizer, delayed neurologic disease progression as measured by Neuropathy Impairment Score-Lower Limbs (NIS-LL) in an 18-month, double-blind, placebo-controlled randomized trial in 128 patients with early-stage transthyretin V30M familial amyloid polyneuropathy (ATTRV30M-FAP). The current post hoc analyses aimed to further evaluate the effects of tafamidis in delaying ATTRV30M-FAP progression in this trial. METHODS: Pre-specified, repeated-measures analysis of change from baseline in NIS-LL in this trial (ClinicalTrials...
April 10, 2017: Amyloid: the International Journal of Experimental and Clinical Investigation
https://www.readbyqxmd.com/read/28391107/the-relationship-between-work-engagement-and-psychological-distress-of-hospital-nurses-and-the-perceived-communication-behaviors-of-their-nurse-managers-a-cross-sectional-survey
#7
Keiko Kunie, Norito Kawakami, Akihito Shimazu, Yuki Yonekura, Yuki Miyamoto
BACKGROUND: Communication between nurse managers and nurses is important for mental health of hospital nurses. OBJECTIVE: The aim of the present study was to investigate the relationship between managers' communication behaviors toward nurses, and work engagement and psychological distress among hospital nurses using a multilevel model. DESIGN: The present study was a cross-sectional questionnaire survey. SETTINGS: The participants were nurses working at three hospitals in Japan...
March 29, 2017: International Journal of Nursing Studies
https://www.readbyqxmd.com/read/28389609/mortality-reduction-for-fever-hyperglycemia-and-swallowing-nurse-initiated-stroke-intervention-qasc-trial-quality-in-acute-stroke-care-follow-up
#8
Sandy Middleton, Kelly Coughlan, George Mnatzaganian, Nancy Low Choy, Simeon Dale, Asmara Jammali-Blasi, Chris Levi, Jeremy M Grimshaw, Jeanette Ward, Dominique A Cadilhac, Patrick McElduff, Janet E Hiller, Catherine D'Este
BACKGROUND AND PURPOSE: Implementation of nurse-initiated protocols to manage fever, hyperglycemia, and swallowing dysfunction decreased death and disability 90 days poststroke in the QASC trial (Quality in Acute Stroke Care) conducted in 19 Australian acute stroke units (2005-2010). We now examine long-term all-cause mortality. METHODS: Mortality was ascertained using Australia's National Death Index. Cox proportional hazards regression compared time to death adjusting for correlation within stroke units using the cluster sandwich (Huber-White estimator) method...
April 7, 2017: Stroke; a Journal of Cerebral Circulation
https://www.readbyqxmd.com/read/28384342/assessing-gene-environment-interaction-effects-of-fto-mc4r-and-lifestyle-factors-on-obesity-using-an-extreme-phenotype-sampling-design-results-from-the-hunt-study
#9
Thea Bjørnland, Mette Langaas, Valdemar Grill, Ingrid Løvold Mostad
BACKGROUND: Our aim was to assess the influence of age, gender and lifestyle factors on the effect of the obesity-promoting alleles of FTO and MCR4. METHODS: The HUNT study comprises health information on the population of Nord-Trøndelag county, Norway. Extreme phenotype participants (gender-wise lower and upper quartiles of waist-hip-ratio and BMI ≥ 35 kg/m2) in the third survey, HUNT3 (2006-08), were genotyped for the single-nucleotide polymorphisms rs9939609 (FTO) and rs17782313 (MC4R); 25686 participants were successfully genotyped...
2017: PloS One
https://www.readbyqxmd.com/read/28371898/longitudinal-association-of-short-term-metronome-paced-heart-rate-variability-and-echocardiographically-assessed-cardiac-structure-at-a-4-year-follow-up-results-from-the-prospective-population-based-carla-cohort
#10
Daniel Medenwald, Cees A Swenne, Stefan Frantz, Sebastian Nuding, Jan A Kors, Diana Pietzner, Daniel Tiller, Karin H Greiser, Alexander Kluttig, Johannes Haerting
Aims: To assess the value of cardiac structure/function in predicting heart rate variability (HRV) and the possibly predictive value of HRV on cardiac parameters. Methods and results: Baseline and 4-year follow-up data from the population-based CARLA cohort were used (790 men, 646 women, aged 45-83 years at baseline and 50-87 years at follow-up). Echocardiographic and HRV recordings were performed at baseline and at follow-up. Linear regression models with a quadratic term were used...
March 23, 2017: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
https://www.readbyqxmd.com/read/28369661/doubly-robust-estimation-of-generalized-partial-linear-models-for-longitudinal-data-with-dropouts
#11
Huiming Lin, Bo Fu, Guoyou Qin, Zhongyi Zhu
We develop a doubly robust estimation of generalized partial linear models for longitudinal data with dropouts. Our method extends the highly efficient aggregate unbiased estimating function approach proposed in Qu et al. (2010) to a doubly robust one in the sense that under missing at random (MAR), our estimator is consistent when either the linear conditional mean condition is satisfied or a model for the dropout process is correctly specified. We begin with a generalized linear model for the marginal mean, and then move forward to a generalized partial linear model, allowing for nonparametric covariate effect by using the regression spline smoothing approximation...
April 3, 2017: Biometrics
https://www.readbyqxmd.com/read/28340126/association-between-socioeconomic-status-and-access-to-care-and-quitting-smoking-with-and-without-assistance
#12
Sarah A Edwards, Russell C Callaghan, Robert E Mann, Susan J Bondy
Introduction: Socio-economic disparities in smoking rates persist, in Ontario, despite public health care and universal tobacco control policies. Mechanisms for continuing disparities are not fully understood. Unequal access or utilization of assistance for cessation may contribute. The objective of this research was to use longitudinal data on smokers to examine the associations between socioeconomic status (SES) and access to care measures and assisted and unassisted quit attempts. Methods: Data were taken from 3578 smokers with at least one follow-up interview participating in the Ontario Tobacco Survey (OTS)...
March 10, 2017: Nicotine & Tobacco Research: Official Journal of the Society for Research on Nicotine and Tobacco
https://www.readbyqxmd.com/read/28338946/instrumental-variable-methods-for-continuous-outcomes-that-accommodate-nonignorable-missing-baseline-values
#13
Ashkan Ertefaie, James H Flory, Sean Hennessy, Dylan S Small
Instrumental variable (IV) methods provide unbiased treatment effect estimation in the presence of unmeasured confounders under certain assumptions. To provide valid estimates of treatment effect, treatment effect confounders that are associated with the IV (IV-confounders) must be included in the analysis, and not including observations with missing values may lead to bias. Missing covariate data are particularly problematic when the probability that a value is missing is related to the value itself, which is known as nonignorable missingness...
March 16, 2017: American Journal of Epidemiology
https://www.readbyqxmd.com/read/28338445/socioeconomic-status-and-outcomes-after-sport-related-concussion-a-preliminary-investigation
#14
Scott L Zuckerman, Brian Holt Zalneraitis, Douglas J Totten, Kolin E Rubel, Andrew W Kuhn, Aaron M Yengo-Kahn, Christopher M Bonfield, Allen K Sills, Gary S Solomon
OBJECTIVE A significant proportion of patients experience long-term symptoms after sport-related concussion (SRC), and several factors have been associated with this protracted recovery. Limited data exist on the role of socioeconomic status (SES) on SRC outcomes. The objective in this study was to conduct a preliminary investigation to determine the effect of SES on outcomes after SRC in student-athletes treated at a regional sports concussion center. METHODS A retrospective cohort study of 282 middle school, high school, and collegiate student-athletes was conducted...
March 24, 2017: Journal of Neurosurgery. Pediatrics
https://www.readbyqxmd.com/read/28334230/guided-bayesian-imputation-to-adjust-for-confounding-when-combining-heterogeneous-data-sources-in-comparative-effectiveness-research
#15
Joseph Antonelli, Corwin Zigler, Francesca Dominici
In comparative effectiveness research, we are often interested in the estimation of an average causal effect from large observational data (the main study). Often this data does not measure all the necessary confounders. In many occasions, an extensive set of additional covariates is measured for a smaller and non-representative population (the validation study). In this setting, standard approaches for missing data imputation might not be adequate due to the large number of missing covariates in the main data relative to the smaller sample size of the validation data...
March 3, 2017: Biostatistics
https://www.readbyqxmd.com/read/28327265/association-between-body-mass-index-and-caries-experience-in-brazilian-children-and-adolescents
#16
Raquel Assed Bezerra da Silva, Driely Barreiros, Sara Oliveira, Lea Assed Bezerra da Silva, Paulo Nelson-Filho, Erika Calvano Küchler
PURPOSE: The purpose of this study was to evaluate the association between caries and body mass index (BMI) deviations in Brazilian schoolchildren and adolescents. METHODS: A total of 237 three- to 15-year-old children, all undergoing treatment in a university pediatric dental clinic, was evaluated. Caretakers answered a questionnaire on sociodemographic, ethnicity, oral hygiene, and dietary information. The children's height was measured in centimeters, the weight in kilograms, and BMIs were calculated...
September 15, 2016: Journal of Dentistry for Children
https://www.readbyqxmd.com/read/28281937/sensitivity-analysis-for-missing-dichotomous-outcome-data-in-multi-visit-randomized-clinical-trial-with-randomization-based-covariance-adjustment
#17
Siying Li, Gary G Koch, John S Preisser, Diana Lam, Matilde Sanchez-Kam
Dichotomous endpoints in clinical trials have only two possible outcomes, either directly or via categorization of an ordinal or continuous observation. It is common to have missing data for one or more visits during a multi-visit study. This paper presents a closed form method for sensitivity analysis of a randomized multi-visit clinical trial that possibly has missing not at random (MNAR) dichotomous data. Counts of missing data are redistributed to the favorable and unfavorable outcomes mathematically to address possibly informative missing data...
2017: Journal of Biopharmaceutical Statistics
https://www.readbyqxmd.com/read/28281895/randomization-based-adjustment-of-multiple-treatment-hazard-ratios-for-covariates-with-missing-data
#18
Diana Lam, Gary G Koch, John S Preisser, Benjamin R Saville, Michael A Hussey
Clinical trials are designed to compare treatment effects when applied to samples from the same population. Randomization is used so that the samples are not biased with respect to baseline covariates that may influence the efficacy of the treatment. We develop randomization-based covariance adjustment methodology to estimate the log hazard ratios and their confidence intervals of multiple treatments in a randomized clinical trial with time-to-event outcomes and missingness among the baseline covariates. The randomization-based covariance adjustment method is a computationally straight-forward method for handling missing baseline covariate values...
2017: Journal of Biopharmaceutical Statistics
https://www.readbyqxmd.com/read/28267796/multivariate-normative-comparisons-using-an-aggregated-database
#19
Joost A Agelink van Rentergem, Jaap M J Murre, Hilde M Huizenga
In multivariate normative comparisons, a patient's profile of test scores is compared to those in a normative sample. Recently, it has been shown that these multivariate normative comparisons enhance the sensitivity of neuropsychological assessment. However, multivariate normative comparisons require multivariate normative data, which are often unavailable. In this paper, we show how a multivariate normative database can be constructed by combining healthy control group data from published neuropsychological studies...
2017: PloS One
https://www.readbyqxmd.com/read/28258365/dosing-and-switching-strategies-for-paliperidone-palmitate-3-month-formulation-in-patients-with-schizophrenia-based-on-population-pharmacokinetic-modeling-and-simulation-and-clinical-trial-data
#20
REVIEW
Mats O Magnusson, Mahesh N Samtani, Elodie L Plan, E Niclas Jonsson, Stefaan Rossenu, An Vermeulen, Alberto Russu
Paliperidone palmitate 3-month formulation (PP3M), a long-acting injectable atypical antipsychotic, was recently approved in the US and Europe for the treatment of schizophrenia in adult patients who have already been treated with paliperidone palmitate 1-month formulation (PP1M) for ≥4 months. This article reviews the pharmacokinetic rationale for the approved dosing regimens for PP3M, dosing windows, management of missed doses and treatment discontinuation, switching to other formulations, and dosing in special populations...
March 4, 2017: CNS Drugs
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