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    Benefit and harm of low-dose aspirin in well-treated hypertensives at different baseline cardiovascular risk

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    BACKGROUND: The effects of aspirin in subjects without cardiovascular disease are controversial. In the intensively treated patients of the Hypertension Optimal Treatment (HOT) Study, randomization to low-dose aspirin (75 mg daily) versus placebo significantly reduced cardiovascular events (-15%) and myocardial infarction (-36%), but increased major bleedings (+65%). The present analyses of HOT Study data aim at identifying subgroups of hypertensives with different benefit-to-harm ratios from aspirin, in order to provide recommendations about the use of aspirin in hypertension. METHODS: The 18 790 hypertensive patients (aspirin 9399, placebo 9391; average treatment duration 3.8 years) were stratified for global cardiovascular risk and for individual risk factors. Subgroup-treatment interaction analyses (end points: cardiovascular events, myocardial infarction, major bleedings) were performed by a Cox proportional hazard model. Relative and absolute benefits and harms were calculated. RESULTS: Interaction analyses indicated that of all subgroups, only patients with serum creatinine > 1.3 mg/dl had a significantly greater reduction of cardiovascular events and myocardial infarction (-13 and -7/1000 patient-years), while risk of bleeding was not significantly different between subgroups. In addition to patients with higher creatinine, a favourable balance between benefit and harm of aspirin was found in subgroups of patients at higher global baseline risk and baseline systolic pressure > or = 180 or diastolic pressure > or = 107 mmHg. CONCLUSIONS: Low-dose aspirin should be recommended to well-treated hypertensive patients with even moderate increase in serum creatinine. Aspirin may also be recommended in well-treated hypertensives at higher global cardiovascular risk or higher initial blood pressures

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    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

    Risk assessment and treatment benefit in intensively treated hypertensive patients of the Hypertension Optimal Treatment (HOT) study

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    BACKGROUND: The Hypertension Optimal Treatment (HOT) Study provided information about cardiovascular events in 18,790 hypertensives, subjected to pronounced blood pressure lowering for a mean of 3.8 years. METHODS AND RESULTS: The HOT Study data have been further analysed after risk stratification of the patients (1999 World Health Organization and International Society of Hypertension guidelines criteria): (i) no patients of the HOT Study were classified as low risk, 50% were classified as medium risk, 20.2% as high risk and 29.8% as very high risk; (ii) incidence of cardiovascular events in these patients with excellent blood pressure control [92% had diastolic blood pressure (DBP) < or = 90 mmHg] remained proportional to pretreatment risk. The relative risk of very high- versus medium-risk strata was between two and three both when HOT Study patients were considered independently of, or within the DBP target group they had been randomized to; and (iii) event rates in all risk strata were calculated to be much lower (possibly 60% lower) than rates expected from baseline risk calculated approximately by the Framingham equation. CONCLUSIONS: The low event rate in HOT Study patients is likely to result from pronounced blood pressure lowering, and is not explained by a lower risk profile than in previous controlled trials of antihypertensive treatment. The persistence of a risk gradient despite intensive blood pressure lowering suggests a combination of blood pressure control with other strategies of risk correction and the need to initiate antihypertensive therapy before complications develop

    Variations on the Author

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    “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

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    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

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    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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    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
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