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Concept: Citation index


Despite growing interest in Open Access (OA) to scholarly literature, there is an unmet need for large-scale, up-to-date, and reproducible studies assessing the prevalence and characteristics of OA. We address this need using oaDOI, an open online service that determines OA status for 67 million articles. We use three samples, each of 100,000 articles, to investigate OA in three populations: (1) all journal articles assigned a Crossref DOI, (2) recent journal articles indexed in Web of Science, and (3) articles viewed by users of Unpaywall, an open-source browser extension that lets users find OA articles using oaDOI. We estimate that at least 28% of the scholarly literature is OA (19M in total) and that this proportion is growing, driven particularly by growth in Gold and Hybrid. The most recent year analyzed (2015) also has the highest percentage of OA (45%). Because of this growth, and the fact that readers disproportionately access newer articles, we find that Unpaywall users encounter OA quite frequently: 47% of articles they view are OA. Notably, the most common mechanism for OA is not Gold, Green, or Hybrid OA, but rather an under-discussed category we dub Bronze: articles made free-to-read on the publisher website, without an explicit Open license. We also examine the citation impact of OA articles, corroborating the so-called open-access citation advantage: accounting for age and discipline, OA articles receive 18% more citations than average, an effect driven primarily by Green and Hybrid OA. We encourage further research using the free oaDOI service, as a way to inform OA policy and practice.

Concepts: Academic publishing, Peer review, Impact factor, Scientific journal, Open source, Open content, Open access, Citation index


BACKGROUND: Tuberculosis (TB) is known to disproportionately affect the most economically disadvantaged strata of society. Many studies have assessed the association between poverty and TB, but only a few have assessed the direct financial burden TB treatment and care can place on households. Patient costs can be particularly burdensome for TB-affected households in sub-Saharan Africa where poverty levels are high; these costs include the direct costs of medical and non-medical expenditures and the indirect costs of time utilizing healthcare or lost wages. In order to comprehensively assess the existing evidence on the costs that TB patients incur, we undertook a systematic review of the literature. METHODS: PubMed, EMBASE, Science Citation Index, Social Science Citation Index, EconLit, Dissertation Abstracts, CINAHL, and Sociological Abstracts databases were searched, and 5,114 articles were identified. Articles were included in the final review if they contained a quantitative measure of direct or indirect patient costs for treatment or care for pulmonary TB in sub-Saharan Africa and were published from January 1, 1994 to Dec 31, 2010. Cost data were extracted from each study and converted to 2010 international dollars (I$). RESULTS: Thirty articles met all of the inclusion criteria. Twenty-one studies reported both direct and indirect costs; eight studies reported only direct costs and one study reported only indirect costs. Depending on type of costs, costs varied from less than I$1 to almost I$600 or from a small fraction of mean monthly income for average annual income earners to over 10 times the annual income that the average person in the income-poorest 20% of the population earns. Out of the eleven types of TB patient costs identified in this review, the costs for hospitalization, medication, transportation, and care in the private sector were largest. CONCLUSION: TB patients and households in sub-Saharan Africa often incurred high costs when utilizing TB treatment and care, both within and outside of Directly Observed Therapy Short-course (DOTS) programs. It is likely that for many households, TB treatment and care-related costs were “catastrophic” because the TB patient costs commonly amounted to 10% or more of per-capita incomes in the countries where the primary studies included in this review were conducted. Our results suggest that policies to decrease direct and indirect TB patient costs are urgently needed to prevent poverty due to TB treatment and care for those affected by the disease.

Concepts: Africa, Tuberculosis, Cost, Science Citation Index, Household income in the United States, Citation index, Social Sciences Citation Index


BACKGROUND: Intravitreal injection therapy (IViT) for retinoblastoma has shown promise in the treatment of vitreous seeds; however, the potential for tumour dissemination following intravitreal penetration has limited its use. This review evaluates the risk of extraocular tumour spread in patients receiving therapeutic intravitreal injections for retinoblastoma. METHODS: PUBMED (1946-present), SCOPUS (all years), Science Citation Index (1900-present) and Conference Proceedings Citation Index-Science (1990-present) electronic databases were searched to identify all published reports of IViT for retinoblastoma in humans. RESULTS: 14 studies with original IViT data were included in this review. A total of 1304 intravitreal injections were given in 315 eyes of 304 patients, with one report of extraocular tumour spread and one patient in whom intravitreal treatment could not be excluded as a contributor to metastatic disease. The proportion of subjects with extraocular tumour spread potentially due to IViT in these combined reports was 0.007 (95% CI 0.0008 to 0.0236), with a mean follow-up of 72.1 months. In a subset of 61 patients receiving IViT via safety enhancing injection techniques (347 injections, 19.6 months mean follow-up), there were no reports of tumour spread. CONCLUSIONS: Local and systemic tumour spread following IViT in cases of retinoblastoma is rare, and this risk is potentially reduced by the use of safety enhancing injection techniques. These results suggest that the risk of tumour spread should not preclude IViT use for carefully selected patients as part of multi-modal globe salvaging therapy.

Concepts: Medicine, Cancer, Metastasis, Oncology, Academic publishing, Science Citation Index, Citation index, Citation indices


This study is aimed at analysing the scientific literature related to physiological responses in synchronized swimmers, produced from 2006 to 2016. A systematic review was conducted using electronic databases (Google Scholar, PubMed, SportDiscus, Web Science, Scielo and Scopus) in national and international journals. The articles were selected using the following inclusion criteria: composed samples of synchronized swimmers of both sexes, articles in English, Spanish and Portuguese, published from 2006 to 2016. Ten studies were included. The concentration of the articles and their publication was as follows: Europe (77%) and North America (23%). The protocols used analyse physiological responses in synchronized swimmers athletes during competitions or laboratory tests, lactate measurements, heart rate, rates of perceived exertion, VO2 and lung volume. The subjects of 100% of the studies included in this review were athletes of junior and senior categories who volunteered. Only 03 of the 10 studies have compared the physiological responses in volunteers who were not synchronized swimmers to synchronized swimmer athletes. The studies were conducted using different methodologies, which makes it difficult to compare them, so the standardization of instruments and definitions is essential for the scientific advancement in this field. In addition, it would be interesting to expand the research of these physiological responses in synchronized swimmers using base level or beginners as sample.

Concepts: Lung, Science, Swimming, Open access, Citation index, Olympic sports, Synchronized swimming


ABSTRACT The publication of scientific information that derives from dual use research of concern (DURC) poses major problems for journals because it brings into conflict the benefits of free access to data and the need to prevent misuse of that information by others. Recently, a group of authors and a major scientific journal addressed the issue of publishing information on a newly discovered, highly lethal toxin that can be delivered to large populations and for which there are no available countermeasures. The journal addressed this conflict by permitting the redaction of information that is normally considered essential for publication. This action establishes a precedent for redaction of sensitive data that also provides an example of responsible scientific publishing. However, this precedent leaves many questions unanswered and suggests a need for a discussion by all stakeholders of scientific information so as to derive normative standards for the publication of DURC.

Concepts: Academic publishing, Science, Open access, Journal, Scientific literature, Citation index, Technical communication, Normative


On 5th December 2012, a scientific article reviewing a change in the feeding behaviour of the European catfish, one of the largest freshwater fish, was published in the American scientific journal, PLOS ONE, an open access journal, which also allows the mass publication of pictures and videos. Within a few days following the publication of this article, it was relayed by numerous web sites and generated a media craze. In this paper, we analyse the circulation of this scientific information in the sphere of Web-based media during the two months following its publication, by revealing the citation mechanisms of the original article and the logic of the Internet users participating in its diffusion. In addition, since the circulation of its informational content travelled beyond linguistic and geographical boundaries, we chose to compare the citation modalities and intertextual relationships of documents in the three countries where the article spread the most widely, namely: France, the United States and Great Britain. Even though our study shows that the media circulation of scientific papers operates in a traditional way, the intertextual analysis underlines the grand variety of participants (such as journalists, non-scientists, fishermen, technology enthusiasts and Internet users) involved in the diffusion of this information, each of them mobilizing different intertextual strategies, according to their various targets. They all transformed, reformulated and appropriated the scientific information according to their own, unique interests. This study also emphasizes the importance of journalistic websites as opinion relays. They were the first diffusers involved in spreading the information but this role was rarely acknowledged by the Internet users - through citations, for example. In contrast, we observed that amateurs' communities (communities of practices and communities of interest of fishermen or of buzz fans), which only became involved in a second temporal phase of the spreading, preferred to build up their credibility through citations of the original article. Finally, this research helps to rethink the mechanisms of the circulation of scientific information in the Web-based media, highlighting both the variety and the inventiveness of the interactions between the academic and public spheres.

Concepts: Academic publishing, Science, Scientific journal, Open access, Scientific literature, Citation index, Open access journal, Public Library of Science


Research has tremendously contributed to the developments in both practical and fundamental aspects of limb prosthetics. These advancements are reflected in scientific articles, particularly in the most cited papers. This article aimed to identify the 100 top-cited articles in the field of limb prosthetics and to investigate their main characteristics. Articles related to the field of limb prosthetics and published in the Web of Knowledge database of the Institute for Scientific Information (ISI) from the period of 1980 to 2012. The 100 most cited articles in limb prosthetics were selected based on the citation index report. All types of articles except for proceedings and letters were included in the study. The study design and level of evidence were determined using Sackett’s initial rules of evidence. The level of evidence was categorized either as a systematic review or meta-analysis, randomized controlled trial, cohort study, case–control study, case series, expert opinion, or design and development. The top cited articles in prosthetics were published from 1980 to 2012 with a citation range of 11 to 90 times since publication. The mean citation rate was 24.43 (SD 16.7) times. Eighty-four percent of the articles were original publications and were most commonly prospective (76%) and case series studies (67%) that used human subjects (96%) providing level 4 evidence. Among the various fields, rehabilitation (47%), orthopedics (29%), and sport sciences (28%) were the most common fields of study. The study established that studies conducted in North America and were written in English had the highest citations. Top cited articles primarily dealt with lower limb prosthetics, specifically, on transtibial and transradial prosthetic limbs. Majority of the articles were experimental studies.

Concepts: Cohort study, Evidence-based medicine, Systematic review, Randomized controlled trial, Academic publishing, Science, Scientific literature, Citation index


Citation metrics and h indices differ using different bibliometric databases. We compiled the number of publications, number of citations, h index and year since the first publication from 340 soil researchers from all over the world. On average, Google Scholar has the highest h index, number of publications and citations per researcher, and the Web of Science the lowest. The number of papers in Google Scholar is on average 2.3 times higher and the number of citations is 1.9 times higher compared to the data in the Web of Science. Scopus metrics are slightly higher than that of the Web of Science. The h index in Google Scholar is on average 1.4 times larger than Web of Science, and the h index in Scopus is on average 1.1 times larger than Web of Science. Over time, the metrics increase in all three databases but fastest in Google Scholar. The h index of an individual soil scientist is about 0.7 times the number of years since his/her first publication. There is a large difference between the number of citations, number of publications and the h index using the three databases. From this analysis it can be concluded that the choice of the database affects widely-used citation and evaluation metrics but that bibliometric transfer functions exist to relate the metrics from these three databases. We also investigated the relationship between journal’s impact factor and Google Scholar’s h5-index. The h5-index is a better measure of a journal’s citation than the 2 or 5 year window impact factor.

Concepts: Academic publishing, Research, World Wide Web, Impact factor, Newspaper, Citation index, Hypertext, Citation impact


We propose a new method to assess the merit of any set of scientific papers in a given field based on the citations they receive. Given a field and a citation impact indicator, such as the mean citation or the [Formula: see text]-index, the merit of a given set of [Formula: see text] articles is identified with the probability that a randomly drawn set of [Formula: see text] articles from a given pool of articles in that field has a lower citation impact according to the indicator in question. The method allows for comparisons between sets of articles of different sizes and fields. Using a dataset acquired from Thomson Scientific that contains the articles published in the periodical literature in the period 1998-2007, we show that the novel approach yields rankings of research units different from those obtained by a direct application of the mean citation or the [Formula: see text]-index.

Concepts: Academic publishing, Science, Novel, Literature, Impact factor, Publishing, Scientific literature, Citation index


This article highlights the issue of wasteful publishing practices that primarily affect non-mainstream science countries and rapidly growing academic disciplines. Numerous start-up open access publishers with soft or nonexistent quality checks and huge commercial interests have created a global crisis in the publishing market. Their publishing practices have been thoroughly examined, leading to the blacklisting of many journals by Jeffrey Beall. However, it appears that some subscription journals are also falling short of adhering to the international recommendations of global editorial associations. Unethical editing agencies that promote their services in non-mainstream science countries create more problems for inexperienced authors. It is suggested to regularly monitor the quality of already indexed journals and upgrade criteria of covering new sources by the Emerging Sources Citation Index (Web of Science), Scopus, and specialist bibliographic databases. Regional awareness campaigns to inform stakeholders of science communication about the importance of ethical writing, transparency of editing services, and permanent archiving can be also helpful for eradicating unethical publishing practices.

Concepts: Academic publishing, Ethics, Writing, Bibliographic databases, Publishing, Editing, Bibliography, Citation index