1,721,110 research outputs found
Study design and statistical analysis of data in human population studies with the micronucleus assay
No full textThe most common study design performed in population studies based on the micronucleus (MN) assay, is the cross-sectional study, which is largely performed to evaluate the DNA damaging effects of exposure to genotoxic agents in the workplace, in the environment, as well as from diet or lifestyle factors. Sample size is still a critical issue in the design of MN studies since most recent studies considering gene-environment interaction, often require a sample size of several hundred subjects, which is in many cases difficult to achieve. The control of confounding is another major threat to the validity of causal inference. The most popular confounders considered in population studies using MN are age, gender and smoking habit. Extensive attention is given to the assessment of effect modification, given the increasing inclusion of biomarkers of genetic susceptibility in the study design. Selected issues concerning the statistical treatment of data have been addressed in this mini-review, starting from data description, which is a critical step of statistical analysis, since it allows to detect possible errors in the dataset to be analysed and to check the validity of assumptions required for more complex analyses. Basic issues dealing with statistical analysis of biomarkers are extensively evaluated, including methods to explore the dose-response relationship among two continuous variables and inferential analysis. A critical approach to the use of parametric and non-parametric methods is presented, before addressing the issue of most suitable multivariate models to fit MN data. In the last decade, the quality of statistical analysis of MN data has certainly evolved, although even nowadays only a small number of studies apply the Poisson model, which is the most suitable method for the analysis of MN data. © The Author 2010. Published by Oxford University Press on behalf of the UK Environmental Mutagen Society. All rights reserved
Harmonisation of the micronucleus assay in human buccal cells - a Human Micronucleus (HUMN) project (www.humn.org) initiative commencing in 2007
No full textFenech, Michael; Bolognesi, Claudia; Kirsch-volders, Micheline; Bonassi, Stefano; Zeiger, Errol; Knasmüller, Siegfried; Holland, Nin
The first report of the Italian Migraine Registry (I-GRAINE)
No full textItalian Migraine Registry (I-GRAINE) is a multicenter (n = 38), prospective, observational, non-interventional study aimed at providing big data on migraine to ensure proper clinical disease management, according to scientific, and sustainability criteria. We enrolled consecutive patients affected by episodic or chronic migraine according to the systematic random method. Information on sociodemographic characteristics, lifestyle, migraine features, patient's journey, and healthcare resource use were gathered using face-to-face interviews.On the date of 31 December 2021, we enrolled 231 patients at 12 headache centers. Most of them were women (84.4%), with high migraine frequency (9.6 ± 6.9 days/month) and severe disability (MIDAS score: 43.0 ± 40.8; HIT-6 score: 60.4 ± 10.6). Only a minority of patients (38.1%) had previously visited a headache center.A clear-cut difference emerged in the proportion of responders to nonspecific acute treatments (43.5-66.7%) compared to triptans (76.3%) and in responders to unspecific prophylaxis (5.4-35%) compared to anti-CGRP monoclonal antibodies (69.2-78.6%). Most patients underwent ≥ 1 specialist visit (66.9%) or diagnostic investigation (77.4%) over the last 3 years-mostly subsidized by our national health system-inappropriate in 64.9% and 25% of the cases, respectively.The I-GRAINE registry is expected to provide a large and exponentially increasing collection of clinical, biological, and epidemiologic information and will contribute to moving migraine out of the shadow cone of marginalization, which has been often relegated up to now
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
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