1,720,966 research outputs found
Multi-state modeling of hospitalized patient data for prediction, etiology, and burden analyses - from hospital-acquired infections to pandemic settings
No full textThis thesis addressed several strategies for avoiding bias and misinterpretationin the analysis of data on hospitalized patients. Specifically, the presentedmethods avoid competing risks, time-dependent, and selection biases. The firstpart of the work outlined how to conduct competing risks analyses in studies intothe epidemiology of S. aureus surgical site infection and pneumonia with complexsampling designs. In these settings, observation of infection as the main eventof interest was prevented by the competing risks of death and discharge alive inthe hospital. In addition to avoiding a competing risks bias, weights were used tomimic a population closer to the more generalizable target population. The estimates properly taking into account these challenges diverge greatly from results based on simpler, yet naive alternatives (non-competing risks, unweighted analyses). The results constitute an important contribution to identifying hospitalized patients who would benefit most from interventions against S. aureus infections.The second section focused on multi-state methodology applied to data onhospitalized COVID-19 patients. In these analyses, a model was used with oneor more intermediate states (e.g. ICU admission, mechanical ventilation, severedisease) along with the terminal states of discharge alive and death. In additionto averting competing risks biases, multi-state methods properly model thetime-varying nature of these intermediate states to avoid time-dependent biases.These models also enable the prediction of clinical courses and the duration ofclinically relevant states. The models were applied to publicly available data published early on during the pandemic that served as a template for analyses in awide range of COVID-19 research. A true strength of the methods is that theycan be performed in real-time, enabling swift analyses in quickly changing circumstances and avoiding a selection bias that can result from omitting currentcases. This aspect was highlighted in the demonstration of analyzing emergingpandemic variants.In the third section, strategies were presented for assessing changes in theburden of infection (modeled as an intermediate event in a multi-state model)after an intervention has been introduced. Previous research has focused onestimating the burden of a time-fixed exposure, or the reduction in burden resultingfrom the total elimination of a time-varying exposure. In this work, estimationfocused on the more likely situation that a prevention leads to a decrease in therate of a hospital-acquired infection. In addition to estimating a reduction in mortality, these methods can be linked with financial data to estimate cost reductions. A simple tool using R code was developed that requires only routinely collected data to estimate the burden.In summary, the methods detailed in this work constitute important optionsfor research on hospital data, whether for nosocomial infections, COVID-19, orfuture pandemics
Management und Behandlungsergebnisse von Patient:innen mit infektiöser Endokarditis am Universitätsklinikum Freiburg : erste Ergebnisse der DERIVE-Registerstudie
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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