1,720,959 research outputs found

    A systematic review of evidence for the appropriateness of neonatal screening programmes for inborn errors of metabolism

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    Background: developments in screening technology and increased understanding of the natural history and treatment of inborn errors of metabolism (IEMs) have produced pressure to extend neonatal screening programmes. This review aims to assess the evidence for the appropriateness of such programmes. Methods: a formal systematic literature review was conducted. Exclusion and inclusion criteria were used to select papers for critical appraisal by pairs of reviewers. Standard criteria were used to assess the appropriateness of neonatal screening for various IEMs. Site visits were conducted to assess new technologies for newborn screening. Results: a total of 1866 papers were identified and 407 systematically selected for full critical appraisal. Published evidence confirmed that universal newborn screening for phenylketonuria (PKU) meets all of the screening criteria and justifies the expense and infrastructure necessary for the collection and testing of neonatal blood spots. There was insufficient evidence in the literature to assess the cost-effectiveness of screening for any other IEMs. There was reasonable evidence to support inclusion in extended neonatal screening of four other IEMs: biotinidase deficiency, congenital adrenal hyperplasia (CAH), medium-chain acyl CoA dehydrogenase (MCAD) deficiency and glutaric aciduria type 1 (GA1). Conclusions: large-scale trials of screening for biotinidase, CAH, MCAD and GA1 should be conducted, with careful evaluation to establish their clinical effectiveness and cost-effectiveness in practice. Screening for the latter two disorders would be dependent upon the use of tandem mass spectrometry (tandem MS). The application of tandem MS to newborn screening requires further evaluation. The extension of neonatal screening programmes to other IEMs is not currently justifie

    Secondary analysis of economic data: a review of cost-benefit studies of neonatal screening for phenylketonuria

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    Study objective: to estimate the net financial benefit of neonatal screening for phenylketonuria (PKU): by a simple pooling of cost data from the literature; and by a more complex modelling approach. Design: a systematic literature review was conducted to identify papers containing data on the monetary costs and benefits of neonatal screening for PKU. The methodological quality of the studies was appraised, and data were extracted on resource use and expenditure. Monetary data were converted to common currency units, and standardised to UK incidence rates. Net benefits were calculated for median, best case and worst case scenarios, and the effect of excluding poor quality studies and data was tested. The net benefit was also estimated from a model based on data from the literature and assumptions appropriate for the current UK situation. Extensive sensitivity analysis was conducted.Main results: the direct net benefit of screening based on the median costs and benefits from the 13 studies identified was 143,400 Pounds per case detected and treated (39,000 Pounds and 241,800 Pounds for worst case and best case scenarios respectively). The direct net benefit obtained by the modelling approach was lower at 93,400 Pounds per case detected and treated. Screening remained cost saving under sensitivity analysis, except with low residential care costs (less than 12,300 Pounds per annum), or very low incidence rates (less than 1 in 27,000). Conclusions: the economic literature on PKU screening is of variable quality. The two methods of secondary analysis lead to the same conclusion: that neonatal PKU screening is worthwhile in financial terms alone in the UK, and that it justifies the infrastructure for collecting and testing neonatal blood samples. This result cannot necessarily be extrapolated to other countrie

    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

    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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    Newborn screening for inborn errors of metabolism: a systematic review

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    Objectives: to establish a database of literature and other evidence on neonatal screening programmes and technologies for inborn errors of metabolism. To undertake a systematic review of the data as a basis for evaluation of newborn screening for inborn errors of metabolism. To prepare an objective summary of the evidence on the appropriateness and need for various existing and possible neonatal screening programmes for inborn errors of metabolism in relation to the natural history of these diseases. To identify gaps in existing knowledge and make recommendations for required primary research. To make recommendations for the future development and organisation of neonatal screening for inborn errors of metabolism in the UK. How the research was conducted: there were three parts to the research. A systematic review of the literature on inborn errors of metabolism, neonatal screening programmes, new technologies for screening and economic factors. Inclusion and exclusion criteria were applied, and a working database of relevant papers was established. All selected papers were read by two or three experts and were critically appraised using a standard format. Seven criteria for a screening programme, based on the principles formulated by Wilson and Jungner (WHO, 1968), were used to summarise the evidence. These were as follows. Clinically and biochemically well-defined disorder. Known incidence in populations relevant to the UK. Disorder associated with significant morbidity or mortality. Effective treatment available. Period before onset during which intervention improves outcome. Ethical, safe, simple and robust screening test. Cost-effectiveness of screening. A questionnaire which was sent to all newborn screening laboratories in the UK. Site visits to assess new methodologies for newborn screening. The classical definition of an inborn error of metabolism was used (i.e., a monogenic disease resulting in deficient activity in a single enzyme in a pathway of intermediary metabolism). Research findings: inborn errors of metabolism. Phenylketonuria (PKU) (incidence 1:12,000) fulfilled all the screening criteria and could be used as the 'gold standard' against which to review other disorders despite significant variation in methodologies, sample collection and timing of screening and inadequacies in the infrastructure for notification and continued care of identified patients. Of the many disorders of organic acid and fatty acid metabolism, a case can only be made for the introduction of newborn screening for glutaric aciduria type 1 (GA1; estimated incidence 1:40,000) and medium-chain acyl CoA dehydrogenase (MCAD) deficiency (estimated incidence 1:8000-1:15,000). Therapeutic advances for GA1 offer prevention of neurological damage but further investigation is required into the costs and benefits of screening for this disorder. MCAD deficiency is simply and cheaply treatable, preventing possible early death and neurological handicap. Neonatal screening for these diseases is dependent upon the introduction of tandem mass spectrometry (tandem MS). This screening could however also simultaneously detect some other commonly-encountered disorders of organic acid metabolism with a collective incidence of 1:15,00

    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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