1,721,032 research outputs found
Why do we continue to use standardized mortality ratios for small area comparisons?
Public health practitioners are often faced with the necessity to compare the mortality experience of different geographical areas. Indirect standardization, producing a 'standardized mortality ratio' (SMR) is the most commonly used technique for doing this. However, as we show, indirect standardization is inappropriate for such comparisons, as SMRs for different geographical areas have different denominators. The fact that indirect standardization is usually chosen for this type of comparison is probably based on two beliefs: (1) that direct standardization yields only a rate rather than a more easily interpreted ratio or index; (2) that direct standardization cannot be carried out in many cases because the sub-group specific mortality rates in the groups to be compared are not available or, in at least some age classes, are based upon such small numbers as to be completely unreliable. In this paper we show that a simple index (the comparative mortality figure) can be calculated from the directly standardized rate in most cases. Using a comparison of the overall mortality experience of electoral wards in Sheffield between 1980 and 1987 we demonstrate also that the advantage gained by the smaller standard error of the SMR is outweighed by the bias inherent in its construction. We recommend that the SMR is used only when absolutely necessary, that is, in the rare circumstance when data are not available for the calculation of age- and sex-specific subgroup rates in the study population
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
The flow cytometric analysis of total p53 protein content and proliferation indices in colorectal cancer, in relation to clinical outcome
This study was undertaken to assess the value of how cytometric measurements of total p53 protein content and proliferation indices derived from in vivo halogenated pyrimidine labelling. Two series of colorectal cancer specimens were studied for which clinical outcome data were recorded. A series of 84 archival, ethanol-fixed, bromodeoxyuridine (BrdUrd) labelled colorectal tumours were analysed by flow cytometry for their total and cell cycle phase p53 protein content using the pAb1801 monoclonal antibody. A second series of 33 freshly obtained tumours was used for assay evaluation and for comparison with the archival material. In the archival series (n = 84), the median p53-pAb1801 LI was 81.9% (range: 11.1-99.8%). In only three tumours could significant amounts of p53 protein not be detected. The median phase specific p53-pAb1801 LI in G0/G1 was 71.6%, in S was 95.5%, and in G2/M was 98.5%. In the series of fresh tumours (n = 33), the median p53-pAb1801 labelling index (LI) was 94.6% (range: 17.9-99.9%). Only two tumours failed to express significant amounts of p53 protein. There was no significant difference in the generally high levels of p53 protein content between the fresh and archival series. Life-table analysis of the patients in the archival series failed to demonstrate a statistical difference in life expectancy in relation to Dukes' stage when rumours were stratified by the median total p53 labelling index. In this study, p53 content and proliferative indices measured by how cytometry do not have independent predictive value over Dukes' grading in determining the outcome of colorectal cancer. Flow cytometry is confirmed as a practical tool for multi-parametric and cell cycle analysis of oncoprotein expression in human tumour biopsies.</p
Variations on the Author
“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
We 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
We 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
We 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.
Author-wise bibliometric analysis based on entropy.</p
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