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Fadel M Megahed L Allison Jones-Farmer Yinjiao Ma Steven E Rigdon 《JMIR Public Health and Surveillance》2022,8(7)
BackgroundSocially vulnerable communities are at increased risk for adverse health outcomes during a pandemic. Although this association has been established for H1N1, Middle East respiratory syndrome (MERS), and COVID-19 outbreaks, understanding the factors influencing the outbreak pattern for different communities remains limited.ObjectiveOur 3 objectives are to determine how many distinct clusters of time series there are for COVID-19 deaths in 3108 contiguous counties in the United States, how the clusters are geographically distributed, and what factors influence the probability of cluster membership.MethodsWe proposed a 2-stage data analytic framework that can account for different levels of temporal aggregation for the pandemic outcomes and community-level predictors. Specifically, we used time-series clustering to identify clusters with similar outcome patterns for the 3108 contiguous US counties. Multinomial logistic regression was used to explain the relationship between community-level predictors and cluster assignment. We analyzed county-level confirmed COVID-19 deaths from Sunday, March 1, 2020, to Saturday, February 27, 2021.ResultsFour distinct patterns of deaths were observed across the contiguous US counties. The multinomial regression model correctly classified 1904 (61.25%) of the counties’ outbreak patterns/clusters.ConclusionsOur results provide evidence that county-level patterns of COVID-19 deaths are different and can be explained in part by social and political predictors. 相似文献
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Lee TK Wang W O'Brien KF Johnke RM Wang T Allison RR Diaz AL 《Phytotherapy research : PTR》2008,22(12):1614-1622
To explore the radioprotective effect of a standardized North American ginseng extract (NAGE) on human peripheral blood lymphocytes (PBL), a micronuclei (MN) assay was conducted in PBL obtained from 12 volunteers. NAGE (50-1000 microg/mL) and WR-1065 (1 mM and 3 mM) were applied to PBL cultures at 0 h and 90 min post-irradiation. It was found that (1) the baseline MN yield of PBL ranged from 14.4 +/- 1.5 to 15.9 +/- 1.5 per 1000 binucleated cells (p > 0.05); after irradiation (1 Gy and 2 Gy), the MN yield increased sharply; (2) MN yields declined with increasing concentrations of NAGE and WR-1065. Even at 90 min post-irradiation of 1 Gy, the maximum level of MN reduction rate caused by NAGE and WR-1065 was 53.8% and 59.2%, respectively; after 2 Gy irradiation, it was 37.3% and 42%, respectively; (3) the MN distribution in PBL followed a non-Poisson distribution in all cases; and (4) both NAGE and WR-1065 showed no significant effect on the proliferation index of lymphocytes. The results indicate that NAGE is a relatively non-toxic natural product, which can be administered as a dietary supplement and has the potential to be a radiation countermeasure. 相似文献
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How Many Imputations are Really Needed? Some Practical Clarifications of Multiple Imputation Theory 总被引:1,自引:0,他引:1
Multiple imputation (MI) and full information maximum likelihood (FIML) are the two most common approaches to missing data
analysis. In theory, MI and FIML are equivalent when identical models are tested using the same variables, and when m, the number of imputations performed with MI, approaches infinity. However, it is important to know how many imputations
are necessary before MI and FIML are sufficiently equivalent in ways that are important to prevention scientists. MI theory
suggests that small values of m, even on the order of three to five imputations, yield excellent results. Previous guidelines for sufficient m are based on relative efficiency, which involves the fraction of missing information (γ) for the parameter being estimated, and m. In the present study, we used a Monte Carlo simulation to test MI models across several scenarios in which γ and m were varied. Standard errors and p-values for the regression coefficient of interest varied as a function of m, but not at the same rate as relative efficiency. Most importantly, statistical power for small effect sizes diminished as
m became smaller, and the rate of this power falloff was much greater than predicted by changes in relative efficiency. Based
our findings, we recommend that researchers using MI should perform many more imputations than previously considered sufficient.
These recommendations are based on γ, and take into consideration one’s tolerance for a preventable power falloff (compared to FIML) due to using too few imputations. 相似文献
66.
Dong Kyu Kim Allison McGeer Elizabeth Uleryk Brenda L. Coleman 《Influenza and other respiratory viruses》2022,16(4):632
BackgroundWhile the high burden of illness caused by seasonal influenza in children and the elderly is well recognize, less is known about the burden in adults 50–64 years of age. The lack of data for this age group is a key challenge in evaluating the cost‐effectiveness of immunization programs. We aimed to assess influenza‐associated hospitalization and mortality rates and case fatality rates for hospitalized cases among adults aged 50–64 years.MethodsThis rapid review was conducted according to the PRISMA; we searched MEDLINE, EMBASE, Cochrane, Web of Science, and grey literature for articles and reports published since 2010. Studies reporting rates of hospitalization and/or mortality associated with laboratory‐confirmed influenza among adults 50–64 or 45–64 years of age for the 2010–11 through 2019–20 seasons were included.ResultsTwenty studies from 13 countries were reviewed. Reported rates of hospitalization associated with laboratory‐confirmed influenza were 5.7 to 112.8 per 100,000. Rates tended to be higher in the 2015–2019 compared with the 2010–2014 seasons and were higher in studies reporting data from high‐income versus low and middle‐income countries. Mortality rates were reported in only one study, with rates ranging from 0.8 to 3.5 per 100,000 in four different seasons. The case fatality rate among those hospitalized with influenza, as reported by population‐based studies, ranged from 1.3% to 5.6%.ConclusionsSeasonal influenza imposes a significant burden of morbidity on adults 50–64 years of age but with high heterogeneity across seasons and geographic regions. Ongoing surveillance is required to improve estimates of burden to better inform influenza vaccination and other public health policies. 相似文献
67.
van Karnebeek Clara D. Blydt-Hansen Ingrid Matthews Allison M. Avramovic Vladimir Price Magda Drogemoller Britt Shyr Casper Lee Jessica Mwenifumbo Jill Ghani Aisha Stockler Sylvia Friedman Jan M. Lehman Anna Ross Colin J. Wasserman Wyeth W. Tarailo-Graovac Maja Horvath Gabriella A. 《Neurogenetics》2021,22(4):251-262
neurogenetics - Monoamine neurotransmitter disorders present predominantly with neurologic features, including dystonic or dyskinetic cerebral palsy and movement disorders. Genetic conditions that... 相似文献
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Bruce MacLeod James Phillips Allison E. Stone Aliya Walji John Koku Awoonor-Williams 《Online Journal of Public Health Informatics》2012,4(1)
This paper describes the software architecture of a system designed in response to the health development potential of two concomitant trends in poor countries: i) The rapid expansion of community health worker deployment, now estimated to involve over a million workers in Africa and Asia, and ii) the global proliferation of mobile technology coverage and use. Known as the Mobile Technology for Community Health (MoTeCH) Initiative, our system adapts and integrates existing software applications for mobile data collection, electronic medical records, and interactive voice response to bridge health information gaps in rural Africa. MoTeCH calculates the upcoming schedule of care for each client and, when care is due, notifies the client and community health workers responsible for that client. MoTeCH also automates the aggregation of health status and health service delivery information for routine reports. The paper concludes with a summary of lessons learned and future system development needs. 相似文献