1,721,209 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
Heart failure: optimizing early detection and subsequent drug treatment in older people
No full textHeart failure (HF) is a progressive syndrome mainly and often encountered in older people, and has been called ‘the cardiovascular epidemic of the 21st century’. With extrapolation of the results of our literature review about the prevalence of HF in the older population at large, we even think the prevalence is underestimated.
The majority of patients with HF is diagnosed and managed in primary care, however, underdiagnosis and suboptimal treatment are common.
The overall aim of this thesis was to assess the effect of a diagnostic-therapeutic approach for HF in older persons who presented to the general practitioner (GP) with shortness of breath on exertion in the previous year.
We performed a selective screening study in which 585 patients aged 65 years or over who presented themselves to the GP in the previous 12 months with shortness of breath on exertion underwent diagnostic investigations. Presence or absence of HF was established by an expert panel. The prevalence was similar for men and women (16.5% and 15.0% (p = 0.62), respectively. Prevalence rates were 2.9% (95% CI 1.8-4.7) for HF with reduced ejection fraction, 12.0% (95% CI 9.5-14.9) for HF with preserved ejection fraction, and 0.9% (95% CI 0.3-2.1) for isolated right-sided HF.
Then we developed a clinical prediction rule based on an existing one created in community-dwelling elderly with a GP’s diagnosis of chronic obstructive pulmonary disease. We validated, updated and extended the original model according to a standardised state-of-the-art stepwise approach in our population of community-dwelling elderly with shortness of breath. The final model with nine predictors resulted in a very good C-statistic of 0.88 (range 0.85 to 0.90), and a net reclassification improvement of 31.0%. We constructed a risk score for practical use. This risk score showed high accuracy with a negative predictive value of 87%, and a positive predictive value of 73%.
In addition, we performed a randomized clinical trial in which only the patients with newly detected HF participated. Randomization was on the level of the GP. Sixteen GPs were randomized to the care as usual group and 14 to the intervention group. The GPs in the latter arm received a single half-day interactive training in the management of HF. At baseline and after six months of follow-up, patients in both the intervention group (n=46) and care as usual group (n=46) were assessed on medication uptake, functionality, health status, and number of health care visits.After six months, uptake of HF medication and health status were similar in the two groups. Interestingly, patients in the intervention group had a longer walking distance with the six-minute walk test than those in the care as usual group (mean difference in all-type heart failure 28.0 (95% CI 2.9 to 53.1) meters). They also had more HF-related GP visits (RR 1.8, 95% CI 1.3 to 2.5), but fewer visits to the cardiologist (RR 0.6, 95% CI 0.3 to 1.1). In both arms, a substantial proportion of patients with HF with reduced ejection fraction were not treated according to guideline recommendations
Differences and similarities in cardiovascular risk between Asian and Caucasian populations
No full textCardiovascular disease (CVD) is the leading cause of death worldwide. Once thought to be a Western disease, CVD has emerged as a public health threat for many low- and middle-income countries. Successful decline of the burden of CVD in high income countries point towards an opportunity for developing countries to avert the rising epidemic of CVD. Given limited resources to allocate to CVD, developing countries like China will want to focus on the most cost-effective and influential prevention and treatment strategies. A first step to arrive at cost-effective interventions is to assess and understand the current cardiovascular risk profiles in these countries and to explore regional differences. Cardiovascular risk factors tend to cluster within individuals in many populations. With increasing numbers of risk factors, the risk for CVD and all-cause mortality increases substantially. However, little evidence is available on the clustering of risk factors and the impact of specific combinations of risk factors on the risk of cardiovascular events between different ethnic groups or regions. In this thesis, we explored the similarities and differences in cardiovascular risk between Asians and Caucasians, with emphasis on clustering of cardiovascular risk factors. Our findings indicate that risk factors have similar effects on CVD between Asian and Caucasian populations. Differences in the cardiovascular risk are likely driven by differences in the distributions of risk factors between regions. Prevention and treatment strategies should be developed according to local needs and priorities and adapted to social, cultural and economic environments before being implemented
Facing dengue in pediatrics: studies in a highly endemic region: Dengue in pediatrics
No full textAn overview of dengue epidemiology in Indonesia over 45 years showed an increase in dengue infections in the adolescent age group since 1999. Clinical and laboratory manifestations in children were mostly fever, petechiae, epistaxis, hepatomegaly, and thrombocytopenia. Encephalopathy and gastrointestinal bleeding were found only in dengue shock syndrome (DSS). Subsequent study demonstrated that in our tertiary care hospital, one third of hospitalized children with dengue fever progressed to DSS, and of dengue hemorrhagic fever (DHF) cases, 6% progressed to DSS. Only fever duration was significantly associated with clinical progression, suggesting that the disease course of dengue in children is predictable and stressing the importance of close clinical monitoring of patients. Further study of the profile and clinical signs in infants with confirmed dengue in a 10-year period showed that two strong indicators of DSS in infants were liver enlargement and fluid accumulation. Diarrhea and cough as atypical clinical presentations were found in one third of dengue in infants. The diagnostic value of warning signs in different age groups of children was also explored, to help clinicians facing dengue in endemic countries. Infants with the warning signs of liver enlargement and clinical fluid accumulation are more likely to progress to severe dengue, while in younger children and adolescents, the warning signs are firstly an increase in hematocrit with concurrent rapid decrease in platelet count, followed by abdominal pain, vomiting, or fluid accumulation. A long-term follow-up study of pediatric DHF patients assessed Carotid intima-media thickness (cIMT) and arterial stiffness to detect preclinical atherosclerosis, comparing a post-DHF group and a control group. The result showed no differences in arterial stiffness; longer follow-up studies are warranted
Effects of heart failure management programmes
No full textAbstract of the thesis “Effects of heart failure management programmes” The main purpose of the studies presented in this thesis, was to assess whether an intensive 1-year intervention at a heart failure clinic for patients with heart failure, NYHA classification III or IV, reduces the incidence of hospitalisation for worsening heart failure and/or all cause mortality and improves functional status and quality of life at acceptable costs and whether the observed effects may be (partly) attributable to beneficial changes in patient adherence to drug therapy. Important differences with many previous studies were that our heart failure clinic was directed by a combination of a clinician and a heart failure nurse and that the study was performed in a country with a relatively strong primary care health-care system. In a systematic review in the beginning of the thesis, the results of previous studies on heart failure management programmes are reviewed critically and their applicability to countries, such as the Netherlands, with well-structured primary care facilities is discussed. In the core chapters of the thesis the main results of the Deventer-Alkmaar Heart Failure study (DEAL-HF study) are presented first: the number of admissions for worsening heart failure and/or all-cause deaths in the intervention group was lower than in the control group (23 vs. 47; relative risk(RR) 0.49; 95% confidence interval 0.30 to 0.81; p= 0.001). There also was an improvement of the left ventricular ejection fraction (LVEF) in the intervention group (plus 2.6%) compared with a decrease in the usual care group (minus 3.1%; p=0.004). Patients in the intervention group were hospitalised for a total of 359 days, compared with 644 days for those in the usual care group. Beneficial effects were also observed on NYHA functional class, quality of life, self-care behaviour and health care costs. Then, several sub-studies within the DEAL-HF population are presented. First, we assessed the effect of the heart failure management programme on adherence of prescribers and patients to the medication regimes: beta-blocker dosaging and the number of patients using spironolactone increased. This may have been an important contributor to the observed improved clinical outcomes. Then we investigated the correlation between the change in a biochemical parameter, NT-proBNP, and the change in quality of life and functional class during the follow-up of the main study. Long-term changes in NT-proBNP were indeed accompanied by similar changes in quality of life, functional status and echo parameters. Finally we studied the costs of the heart failure management programme in relation to the observed effects. This more detailed analysis of the costs and effects of the heart failure management programme studied in the DEAL HF study confirms that such a programme exerts beneficial clinical benefit and saves costs
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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