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Julia G. Poirier Laura L. Faye Apostolos Dimitromanolakis Andrew D. Paterson Lei Sun Shelley B. Bull 《Genetic epidemiology》2015,39(7):518-528
The “winner's curse” is a subtle and difficult problem in interpretation of genetic association, in which association estimates from large‐scale gene detection studies are larger in magnitude than those from subsequent replication studies. This is practically important because use of a biased estimate from the original study will yield an underestimate of sample size requirements for replication, leaving the investigators with an underpowered study. Motivated by investigation of the genetics of type 1 diabetes complications in a longitudinal cohort of participants in the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) Genetics Study, we apply a bootstrap resampling method in analysis of time to nephropathy under a Cox proportional hazards model, examining 1,213 single‐nucleotide polymorphisms (SNPs) in 201 candidate genes custom genotyped in 1,361 white probands. Among 15 top‐ranked SNPs, bias reduction in log hazard ratio estimates ranges from 43.1% to 80.5%. In simulation studies based on the observed DCCT/EDIC genotype data, genome‐wide bootstrap estimates for false‐positive SNPs and for true‐positive SNPs with low‐to‐moderate power are closer to the true values than uncorrected naïve estimates, but tend to overcorrect SNPs with high power. This bias‐reduction technique is generally applicable for complex trait studies including quantitative, binary, and time‐to‐event traits. 相似文献
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Melissa Sattler Laura Hopkins Elizabeth Anderson Steeves Angelica Cristello Morgan Mccloskey Joel Gittelsohn 《Ecology of food and nutrition》2015,54(4):380-396
This study explores food preparation behaviors, including types of food prepared, methods of preparation, and frequency of preparation of low-income urban African American youth ages 9–15 in Baltimore City (n = 289) and analyzes a potential association to diet quality as measured through Healthy Eating Index 2010 (HEI) scores. Overall, the youth prepared their own food 6.7 ± 0.33 times per week without significant differences between age groups or genders as measured through pairwise comparison of means. Cereal, noodles, and sandwiches were amongst the foods prepared most frequently. Linear regression analysis found youth food preparation frequency was not significantly associated with total HEI (p = 0.59), sodium (p = 0.58), empty calories (p = 0.96), or dairy scores (p = 0.12). Younger age was associated with higher total HEI scores (p = 0.012) and higher dairy scores (p = 0.01) and female gender was associated with higher total HEI scores (p = 0.03), higher sodium scores (p = 0.03), and lower dairy scores (p = 0.008). 相似文献
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Background
Further efforts are warranted to identify innovative approaches to best implement competencies in nursing education. To bridge the gap between competency-based education, practice, and implementation of knowledge, skills, and attitudes, one emerging approach is entrustable professional activities (EPAs).Purpose
The objective of this study was to introduce the concept of EPAs as a framework for curriculum and assessment in graduate nursing education and training.Methods
Seven steps are provided to develop EPAs for nurses through the example of a quality and safety EPA. The example incorporates the Quality and Safety Education for Nurses (QSEN) patient safety competencies and evidence-based literature.Findings
EPAs provide a practical approach to integrating competencies in nursing as quality and safety are the cornerstones of nursing practice, education, and research.Discussion
Introducing the EPA concept in nursing is timely as we look to identify opportunities to enhance nurse practitioner (NP) training models and implement nurse residency programs. 相似文献996.
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Successful management of severe red blood cell alloimmunization in pregnancy with a combination of therapeutic plasma exchange,intravenous immune globulin,and intrauterine transfusion 下载免费PDF全文
Laura C. Nwogu Kenneth J. Moise Jr Kimberly L. Klein Hlaing Tint Brian Castillo Yu Bai 《Transfusion》2018,58(3):677-684
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