1,721,007 research outputs found
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
In ‘real world’ patients with COPD, exacerbation history, and not blood eosinophils, is the most reliable predictor of future exacerbations
No full textINTRODUCTION: There is an interest in the role of blood eosinophils for predicting inhaled corticosteroid (ICS) response in chronic obstructive pulmonary disease (COPD). Most data are from interventional clinical studies; data from unselected real-world populations may help better inform treatment decisions. DACCORD is a non-interventional real-world study. Cohort 3 recruited patients with COPD who had received triple therapy for ≥ 6 months; prior to entry patients either continued triple therapy, or switched to a long-acting muscarinic antagonist/long-acting beta(2)-agonist (LABA/LAMA), and were followed for 12 months. METHODS: For these post-hoc analyses, patients were divided into four groups based on exacerbation history and baseline blood eosinophil count ( 300 cells/µL). Exacerbation rates were calculated overall and for the two treatments. RESULTS: Among the 430 patients in the current analyses, the largest groups had low exacerbation history with high (44.2%) or low eosinophils (36.7%). Most patients did not exacerbate during follow-up (68.8% overall; 83.2% and 63.7% with LABA/LAMA and triple therapy). The highest exacerbation rates were in groups with high exacerbation history, differing significantly in the overall analyses from those with low exacerbation history (matched by eosinophil count); rates did not differ when grouped by eosinophil count (matched by exacerbation history). CONCLUSIONS: Although most patients in these analyses did not exacerbate during follow-up, whereas exacerbation history is a predictor of future exacerbations, blood eosinophil count is not. This suggests that although eosinophil count may help to guide ICS initiation, this is less of a consideration when ‘stepping-down’ from triple therapy to a LABA/LAM
COPD Assessment Test Changes from Baseline Correlate with COPD Exacerbations: A Longitudinal Analysis of the DACCORD Observational Study
No full textAbstract Purpose A number of analyses have shown the immediate impact of COPD exacerbations on health status. However, none evaluated the long-term correlation between health status and the occurrence of exacerbations. Methods DACCORD is an observational study in patients with COPD recruited across Germany following initiation or change in COPD maintenance medication. Data collected include COPD Assessment Test (CAT) total score on entry and after 1 and 2 years, and the occurrence of exacerbations. We analysed the correlation between change from baseline in CAT total score and exacerbations, after excluding patients who exacerbated during the quarter immediately prior to the CAT assessment of interest. Results The initial correlation analysis was performed in 6075 patients, 28% with ≥ 1 exacerbation over the 2-year follow-up, and 58% with a clinically relevant CAT improvement. There was a significant correlation between exacerbations over 2 years and CAT change from baseline at Year 2 ( p = 0.0041). The Spearman’s correlation coefficient was 0.03711, indicating very weak correlation—potentially driven by the high proportion of non-exacerbating patients. In a subsequent logistic regression, the probability of experiencing frequent (≥ 2 per year) or severe exacerbations was higher in patients with worsening in CAT total score ( p < 0.001). However, the probability of a patient exacerbating in Year 1 or Year 2 did not correlate with CAT change. Conclusions In this population (initiating or changing maintenance COPD medication), patients with frequent or severe exacerbations had a long-term worsening in health status (beyond the acute effect of an exacerbation) compared with patients who do not exacerbate
The ‘real-life’ COPD patient in Germany: The DACCORD study
No full textAbstractIntroductionDACCORD is an ongoing, longitudinal, non-interventional study within the German COPD National Prospective Registry. This manuscript describes the baseline characteristics of the first 5924 participants, recruited between November 2012 and November 2013.MethodsThe main inclusion criteria are a physician diagnosis of COPD, age ≥40 years, and initiating or changing COPD maintenance medication. Data collected included: Demographic and disease characteristics; prescribed medication; symptoms; COPD Assessment Test (CAT); modified Medical Research Council dyspnoea score (mMRC); exacerbations; comorbidities; and forced expiratory volume in 1 s (FEV1).ResultsApproximately 60% of the population are male, with mean age of 65.7 years and FEV1 61.6% predicted. On entry to the study the majority of patients reported symptoms, most commonly exertional dyspnoea (85.9%) and cough (65.7%). According to GOLD 2010, 48.6% of patients were classified as GOLD II. GOLD 2011 classification was influenced by the symptoms criterion: 43.7 and 45.3% of patients were classified as GOLD B or D using CAT, compared with 26.4 and 34.0%, respectively, using mMRC. The majority of patients were receiving a LAMA-containing regimen, with 39.4% overall receiving ICS. A total of 78.3% of patients reported at least one comorbidity, most commonly cardiovascular.ConclusionIn conclusion, DACCORD is a large, prospective, non-interventional study that provides an informative and intriguing picture of the typical COPD patient in Germany
Impact of switching from triple therapy to dual bronchodilation in COPD: the DACCORD ‘real world’ study
No full textINTRODUCTION: Chronic obstructive pulmonary disease (COPD) guidelines recommend reserving triple therapy of inhaled corticosteroid (ICS), long-acting β(2)-agonist (LABA) and long-acting muscarinic antagonist (LAMA) for patients with exacerbations despite dual therapy. However, many patients receive triple therapy without a clear indication. For these patients, it would be useful to know whether ICS can be withdrawn. METHODS: DACCORD was a longitudinal, non-interventional ‘real-world’ study in three cohorts. This manuscript describes the results of Cohort 3, which recruited patients with COPD who had received triple therapy for ≥ 6 months. Prior to entry, each patient’s physician decided to continue triple therapy, or switch to a LABA/LAMA; patients were then followed for 12 months, with exacerbations and COPD Assessment Test (CAT) data recorded every 3 months. The primary endpoint was the time until COPD worsening, defined as the occurrence of a moderate/severe exacerbation or clinically relevant CAT worsening. RESULTS: Of the 1192 patients recruited into the study, 967 completed the end-of-study visit and ≥ 2 of the three interim visits, 292 and 675 receiving LABA/LAMA and triple therapy, respectively. Most baseline demographics were similar between the two groups. A lower proportion of patients in the LABA/LAMA group had COPD worsening than with triple therapy (32.5% vs 55.7% at 12 months), with the time to worsening extended in the LABA/LAMA group (hazard ratio 2.004, p < 0.001). In addition, a significantly lower proportion of patients in the LABA/LAMA group exacerbated (18.5% vs 28.7%; p < 0.001), accompanied by a greater improvement from baseline in CAT total score. Overall, fewer patients in the LABA/LAMA group reported adverse events than in the triple therapy group (12.9% vs 15.1%). CONCLUSIONS: These results suggest that in a real world setting physicians are able to identify patients who can be ‘stepped down’ from triple therapy to LABA/LAMA. Following step down, there was no overall decline in COPD—indeed, some patients had better outcomes
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
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