bims-evares Biomed News
on Evaluation of research
Issue of 2019–06–02
twenty papers selected by
Thomas Krichel, Open Library Society



  1. Gigascience. 2019 Jun 01. pii: giz053. [Epub ahead of print]8(6):
       BACKGROUND: The academic publishing world is changing significantly, with ever-growing numbers of publications each year and shifting publishing patterns. However, the metrics used to measure academic success, such as the number of publications, citation number, and impact factor, have not changed for decades. Moreover, recent studies indicate that these metrics have become targets and follow Goodhart's Law, according to which, "when a measure becomes a target, it ceases to be a good measure."
    RESULTS: In this study, we analyzed >120 million papers to examine how the academic publishing world has evolved over the last century, with a deeper look into the specific field of biology. Our study shows that the validity of citation-based measures is being compromised and their usefulness is lessening. In particular, the number of publications has ceased to be a good metric as a result of longer author lists, shorter papers, and surging publication numbers. Citation-based metrics, such citation number and h-index, are likewise affected by the flood of papers, self-citations, and lengthy reference lists. Measures such as a journal's impact factor have also ceased to be good metrics due to the soaring numbers of papers that are published in top journals, particularly from the same pool of authors. Moreover, by analyzing properties of >2,600 research fields, we observed that citation-based metrics are not beneficial for comparing researchers in different fields, or even in the same department.
    CONCLUSIONS: Academic publishing has changed considerably; now we need to reconsider how we measure success.
    Keywords:  Goodhart’s Law; academic publishing metrics; big data; data science; science of science; scientometrics
    DOI:  https://doi.org/10.1093/gigascience/giz053
  2. BMC Med Res Methodol. 2019 May 31. 19(1): 112
       BACKGROUND: From 2005 to 2010, we conducted 2 randomized studies on a journal (Medicina Clínica), where we took manuscripts received for publication and randomly assigned them to either the standard editorial process or to additional processes. Both studies were based on the use of methodological reviewers and reporting guidelines (RG). Those interventions slightly improved the items reported on the Manuscript Quality Assessment Instrument (MQAI), which assesses the quality of the research report. However, masked evaluators were able to guess the allocated group in 62% (56/90) of the papers, thus presenting a risk of detection bias. In this post-hoc study, we analyse whether those interventions that were originally designed for improving the completeness of manuscript reporting may have had an effect on the number of citations, which is the measured outcome that we used.
    METHODS: Masked to the intervention group, one of us used the Web of Science (WoS) to quantify the number of citations that the participating manuscripts received up December 2016. We calculated the mean citation ratio between intervention arms and then quantified the uncertainty of it by means of the Jackknife method, which avoids assumptions about the distribution shape.
    RESULTS: Our study included 191 articles (99 and 92, respectively) from the two previous studies, which all together received 1336 citations. In both studies, the groups subjected to additional processes showed higher averages, standard deviations and annual rates. The intervention effect was similar in both studies, with a combined estimate of a 43% (95% CI: 3 to 98%) increase in the number of citations.
    CONCLUSIONS: We interpret that those effects are driven mainly by introducing into the editorial process a senior methodologist to find missing RG items. Those results are promising, but not definitive due to the exploratory nature of the study and some important caveats such as: the limitations of using the number of citations as a measure of scientific impact; and the fact that our study is based on a single journal. We invite journals to perform their own studies to ascertain whether or not scientific repercussion is increased by adhering to reporting guidelines and further involving statisticians in the editorial process.
    Keywords:  Number of citations; Peer-review; Reporting guidelines; Reproducibility; Transparency
    DOI:  https://doi.org/10.1186/s12874-019-0746-4
  3. J Clin Epidemiol. 2019 May 28. pii: S0895-4356(18)31114-4. [Epub ahead of print]
       OBJECTIVES: To investigate the general characteristics, methodological and reporting quality of network meta-analyses (NMAs) published in the Cochrane library.
    STUDY DESIGN AND SETTING: We conducted a comprehensive search of the Cochrane library in April 2018 and included 42 NMAs. We used AMSTAR 2 to assess methodological quality and PRISMA-NMA for reporting quality. Stratified analysis and correlation analysis were conducted to explore the factors that might affect quality.
    RESULTS: 42 NMAs investigated 29 topics. The compliance of PRISMA-NMA was moderate. Only 26.2% NMAs described the geometry of network, 64.3% presented the network plot, and 33.3% assessed the inconsistency. The overall methodological quality was low. Only 11.9% NMAs explained the selection of study designs, and 40.5% investigated the publication bias. The compliance of PRISMA-NMA was higher with the increase of the AMSTAR 2 compliance rates (Spearman's ρ = 0.630, P=0.000). NMAs with statistical or epidemiological authors often better reported the titles (P=0.032). Compared with non-funding NMAs, non-industry funding NMAs often better reported data collection process (P=0.028), planned methods of analysis (P=0.034), and synthesis of results (P=0.028).
    CONCLUSION: The quality still needs to be further improved, especially referring to the assessment of publication bias, the geometry of network, assessment and exploration of inconsistency.
    Keywords:  AMSTAR 2; Cochrane library; Meta-epidemiology; Network meta-analyses; PRISMA-NMA; Quality
    DOI:  https://doi.org/10.1016/j.jclinepi.2019.05.022
  4. Int J Methods Psychiatr Res. 2019 May 27. e1784
       OBJECTIVES: The article aims to evaluate how study designs and data analysis methods in psychiatric studies have changed over the last 22 years.
    METHODS: This study involved a total of 320 papers published in 1996 and 2018 in the American Journal of Psychiatry, Acta Psychiatrica Scandinavica, British Journal of Psychiatry, and JAMA Psychiatry. We manually reviewed the articles to determine the way in which they reported the study characteristics and the methods applied in data analysis.
    RESULTS: The statistical intensity in psychiatric journals has changed over the past 20 years. Traditional methods of testing statistical significance were widely used both in 1996 and in 2018. In 2018, there was an increase in reporting more complex methods, such as multivariable regression models, multilevel modelling, and intracluster correlation methods. However, computationally complex data mining or machine learning procedures were not adopted by psychiatric researchers.
    CONCLUSION: The increase in statistical intensity in the literature suggests that readers of prominent psychiatric journals must possess a substantial level of statistical expertise if they wish to critically evaluate the findings published in these journals. It is essential to include an awareness of this substantial change in data analysis methods in psychiatric undergraduate and postgraduate education.
    Keywords:  data analysis; psychiatry; publications; statistics
    DOI:  https://doi.org/10.1002/mpr.1784
  5. J Clin Epidemiol. 2019 May 24. pii: S0895-4356(18)30857-6. [Epub ahead of print]
       OBJECTIVE: To systematically survey the methodological literature and collect suggested criteria for assessing the credibility of effect modification and associated rationales.
    STUDY DESIGN: We searched MEDLINE, Embase, textbook chapters to March 2018 for publications providing guidance for assessing the credibility of effect modification identified in randomized trials or meta-analyses. Teams of two investigators independently identified eligible publications and extracted credibility criteria and authors' rationale, reaching consensus through discussion. We created a taxonomy of criteria that we iteratively refined during data abstraction.
    RESULTS: We identified 150 eligible publications that provided 36 criteria and associated rationales. Frequent criteria included: significant test for interaction (n=54); a priori hypothesis (n=49); providing a causal explanation (n=47); accounting for multiplicity (n=45); testing a small number of effect modifiers (n=38); and pre-specification of analytic details (n=39). For some criteria, we found more than one rationale; some criteria were connected through a common rationale. For some criteria, experts disagreed regarding their suitability (e.g. added value of stratified randomization; trustworthiness of biologic rationales).
    CONCLUSION: Methodologists have expended substantial intellectual energy providing criteria for critical appraisal of apparent effect modification. Our survey highlights popular criteria, expert agreement and disagreement, and where more work is needed, including testing criteria in practice.
    Keywords:  Clinical Trials as Topic (MeSH); Epidemiologic Methods (MeSH); Health Care Evaluation Mechanisms (MeSH); Meta-Analysis as Topic (MeSH); precision medicine (MeSH); subgroup analysis
    DOI:  https://doi.org/10.1016/j.jclinepi.2019.05.014
  6. Healthc Inform Res. 2019 Apr;25(2): 61-72
       Objectives: This paper aims to provide a theoretical clarification of the health informatics field by conducting a quantitative review analysis of the health informatics literature. And this paper aims to map scientific networks; to uncover the explicit and hidden patterns, knowledge structures, and sub-structures in scientific networks; to track the flow and burst of scientific topics; and to discover what effects they have on the scientific growth of health informatics.
    Methods: This study was a quantitative literature review of the health informatics field, employing text mining and bibliometric research methods. This paper reviews 30,115 articles with health informatics as their topic, which are indexed in the Web of Science Core Collection Database from 1974 to 2018. This study analyzed and mapped four networks: author co-citation network, co-occurring author keywords and keywords plus, co-occurring subject categories, and country co-citation network. We used CiteSpace 5.3 and VOSviewer to analyze data, and we used Gephi 0.9.2 and VOSviewer to visualize the networks.
    Results: This study found that the three major themes of the literature from 1974 to 2018 were the utilization of computer science in healthcare, the impact of health informatics on patient safety and the quality of healthcare, and decision support systems. The study found that, since 2016, health informatics has entered a new era to provide predictive, preventative, personalized, and participatory healthcare systems.
    Conclusions: This study found that the future strands of research may be patient-generated health data, deep learning algorithms, quantified self and self-tracking tools, and Internet of Things based decision support systems.
    Keywords:  Algorithms; Data Mining; Machine Learning; Medical Informatics; Publications
    DOI:  https://doi.org/10.4258/hir.2019.25.2.61
  7. Clin Orthop Relat Res. 2019 May 13.
       BACKGROUND: In general, journals can be divided in three categories: subscription-model, open-access, and hybrid (that is, open-access by choice). One measure of an article's impact is the number of citations it receives after publication. Open-access publishing may make articles more widely available because there is no financial barrier to a reader seeing the full-text version. As a result, we wondered whether articles published in fully open-access journals would be more likely to be cited than articles in other kinds of journals.
    QUESTIONS/PURPOSES: We assessed the yearly number and proportion of poorly cited articles published in orthopaedic journals and compared the proportion of poorly cited articles that were published in subscription-model journals with the proportion of poorly cited articles that were published in open-access and hybrid journals.
    METHODS: We identified all original articles (n = 135,029) published in orthopaedic peer-reviewed journals (n = 204) that were active from 2002 to 2012 and indexed in the Scopus® citation database. For each journal, we recorded the type of access (subscription-model, open-access, or hybrid journal), their most-recent CiteScore, the number of well- and poorly cited articles per year (more than five versus five or fewer citations after publication) calculated from the date of publication until December 31, 2017 (data collection April 2018), and then calculated if the journals themselves were poorly cited per year (defined as journals that published 75% or more articles ranked as poorly cited per year). We compared the proportion of poorly cited articles in subscription-model journals with the proportion of poorly cited articles in open-access journals. Additionally, we compared these with hybrid journals.
    RESULTS: In total, 48,133 (36%) articles were classified as poorly cited. The total number and proportion of poorly cited articles increased over the years, from 2121 of 7860 (27%) in 2002 to 6927 of 16,282 (43%) in 2012. The proportion of poorly cited articles in subscription-model journals increased from 226 of 395 (57%) in 2002 to 411 of 578 (71%) in 2012. The proportion of poorly cited articles in open-access journals decreased from 264 of 434 (61%) in 2002 to 296 of 801 (37%) in 2006, and then increased again to 1387 of 2259 (61%) in 2012. When we compared yearly proportions of poorly cited articles in subscription-model versus open-access journals using Mann-Whitney U tests, we only found a difference in 2012, with a higher proportion of poorly cited articles in subscription-model journals that year (median [IQR] of poorly cited article proportions for open-access, 0.61; IQR, 0.38-0.96 and subscription-model journals, 0.92; IQR, 0.54-1.0; p = 0.049). Comparisons of poorly cited articles for all three types of access showed lower proportions of poorly cited articles in hybrid journals for each year, with the lowest proportion found in 2002 (0.20; IQR, 0.09-0.67; p = 0.003).
    CONCLUSIONS: We found no difference in the likelihood that an article would be cited based on whether the article appeared was published in a subscription-model journal or an open-access journal. A future study might compare open-access and paywall articles on similar topics published in the same journal or investigate the characteristics of poorly cited articles, so that researchers and editorial staffs might understand which topics are more impactful and to determine if any important work is less-well appreciated. Additionally, an article-by-article analysis will provide more insight in citation rates for articles published within hybrid journals.
    LEVEL OF EVIDENCE: Level III, therapeutic study.
    DOI:  https://doi.org/10.1097/CORR.0000000000000727
  8. Plast Reconstr Surg. 2019 Jun;143(6): 1798-1806
       BACKGROUND: Participation in scientific meetings yields multiple benefits, yet participation opportunities may not be equally afforded to men and women. The authors' primary goal was to evaluate the representation of men and women at five major academic plastic surgery meetings in 2017. Secondarily, the authors used bibliometric data to compare academic productivity between male and female physician invited speakers or moderators.
    METHODS: The authors compiled information regarding male and female invited speakers from meeting programs. Bibliometric data (h-index, m-value) and metrics of academic productivity (numbers of career publications, publications in 2015 to 2016, career peer-reviewed publications, first and senior author publications) for invited speakers were extracted from Scopus and analyzed.
    RESULTS: There were 282 academic physician invited speakers at the five 2017 meetings. Women constituted 14.5 percent. Univariate analysis showed no differences in h-index, m-value, or numbers of total career publications or first and last author publications at the assistant and associate professor ranks, but higher values for men at the professor level. A model of academic rank based on bibliometric and demographic variables showed male gender significantly associated with increased probability of holding a professor title, even when controlling for academic achievement markers (OR, 2.17; 95 percent CI, 1.61 to 2.92).
    CONCLUSIONS: Although the impact of women's published work was no different than that of men among junior and midcareer faculty, women constitute a minority of invited speakers at academic plastic surgery meetings. Sponsorship is imperative for achieving gender balance within plastic surgery and to ultimately create more diverse and effective teams to improve patient care.
    DOI:  https://doi.org/10.1097/PRS.0000000000005672
  9. J Glob Health. 2019 Jun;9(1): 010425
       Background: The high disease burden of respiratory syncytial virus (RSV) infection and renewed focus on developing a vaccine has led to sustained interest in published RSV-related research. The majority of this research comes from Europe and North/Central America and this landscape review aimed to identify and characterize RSV-related research published during 2011-2015 in these geographical areas.
    Methods: We conducted a literature review on electronic databases Scopus and Web of Science to identify published studies investigating RSV throughout Europe and North/Central America. We stratified RSV-related publications between 2011-2015 by study type, country, research institution and funding body.
    Results: The annual published output of RSV-related research has increased by 29% over the period 2011-2015. Eighty seven percent (13/15) of the most highly cited papers on RSV during this period were from North America. US universities with the highest number of RSV-related publications included Emory (n = 23), Vanderbilt (n = 23), University of Michigan (n = 21) and Ohio State (n = 20). The UK (n = 125), Netherlands (n = 97) and Spain (n = 76) were major European contributors to RSV-related publications. University Medical Centre Utrecht (n = 40) and Imperial College London (n = 28) were the European universities with the largest number of RSV-related publications. The National Institutes of Health provided funding for one quarter of all RSV-related publications. However, few countries in Eastern Europe, Central America and the Caribbean published RSV-related research. Few epidemiological studies focused on adult populations over 18 years old (n = 28, 7%) with only five publications specifically investigating elderly populations over 65.
    Conclusions: This review identifies key regions and research institutions which contributed to RSV-related research during 2011-2015 as well as the donor agencies which supported this research. Further research investment is required in a number of countries. More research in the elderly and in high-risk adults is required given the lack of studies pertaining to these populations. Researchers and those commissioning research can use the data from this review to identify productive research institutions and geographical gaps in RSV research.
    DOI:  https://doi.org/10.7189/jogh.09.010425
  10. Comput Biol Med. 2019 Apr 16. pii: S0010-4825(19)30116-7. [Epub ahead of print]109 322-332
       BACKGROUND: A large number of neurology case reports have been published, but it is a challenging task for human medical experts to explore all of these publications. Text mining offers a computational approach to investigate neurology literature and capture meaningful patterns. The overarching goal of this study is to provide a new perspective on case reports of neurological disease and syndrome analysis over the last six decades using text mining.
    METHODS: We extracted diseases and syndromes (DsSs) from more than 65,000 neurology case reports from 66 journals in PubMed over the last six decades from 1955 to 2017. Text mining was applied to reports on the detected DsSs to investigate high-frequency DsSs, categorize them, and explore the linear trends over the 63-year time frame.
    RESULTS: The text mining methods explored high-frequency neurologic DsSs and the relationships between them from 1955 to 2017. We detected more than 18,000 unique DsSs and found 10 categories of neurologic DsSs. While the trend analysis showed the increasing trends in the case reports for top-10 high-frequency DsSs, the categories had mixed trends.
    CONCLUSION: Our study provided new insights into the application of text mining methods to investigate DsSs in a large number of medical case reports that occur over several decades. The proposed approach can be used to provide a macro level analysis of medical literature by discovering interesting patterns and tracking them over several years to help physicians explore these case reports more efficiently.
    Keywords:  Medical case report; Neurology; Syndrome; Text mining; Topic modeling: disease
    DOI:  https://doi.org/10.1016/j.compbiomed.2019.04.008
  11. Int J Food Sci Nutr. 2019 May 29. 1-9
      Total-scale quantitative research literature analysis on the food toxicology scientific field has yet to be conducted. In this work, we identified and analysed food toxicology publications in the existing scientific literature. A literature search was performed with the online Web of Science database. Full records and cited references of the 73,099 identified manuscripts were imported into VOSviewer software for analysis. This research field has been growing steadily since the 1990s. Article to review ratio was 7.4:1. The publications were mainly related to toxicology, environmental sciences, food science and technology, pharmacology/pharmacy and biochemistry/molecular biology. The United States and China are major contributors to food toxicology research, followed by other European and Asian countries. The prolific authors have formed three major clusters within a citation network. Toxic or hazardous chemicals related to food with high citations included aflatoxin, dioxin, fumonisin, malondialdehyde, mycotoxin, ochratoxin, phthalate, and polychlorinated biphenyl.
    Keywords:  Food toxicology; aflatoxin; dioxin; fumonisin; malondialdehyde; mycotoxin
    DOI:  https://doi.org/10.1080/09637486.2019.1620184
  12. Environ Sci Pollut Res Int. 2019 May 26.
      Waste electrical and electronic equipment (WEEE) contains both toxic and valuable materials. Due to rapid development of information and communication technologies (ICT), a large amount of WEEE have been produced, leading to increasing academic efforts in this field. This study aims to depict the trends and features of WEEE-related studies through a bibliometric analysis. The results show that the total number of WEEE-related publications had sharply increased, with China as the leading country. University of Chinese Academy of Sciences is the most productive WEEE-related research institution, while Mai BX is the most productive author. As such, Waste Management, Journal of Cleaner Production, and Environmental Science & Technology are the most influential journals. The research hotspots of WEEE mainly focus on the recycling and treatment technologies, environmental impacts, and relevant policies of WEEE. By tracing the evolutionary pathway of WEEE research, it is clear that the research frontiers have switched from electronic equipment, extended producer responsibility, sediment, environment and design, risk assessment to life cycle assessment, mobile phone, and behaviors. This study provides valuable insights to those WEEE-related scholars so that they can identify their own research topics and partners. This paper is one of the first studies in WEEE research field that offers critical discussions and suggestions related to research development and future trends, and used visualized tools to present the holistic picture of this field.
    Keywords:  Bibliometric analysis; Governance; Trends and features; Waste electrical and electronic equipment (WEEE); Web of science
    DOI:  https://doi.org/10.1007/s11356-019-05409-2
  13. JAMA Netw Open. 2019 May 03. 2(5): e195000
       Importance: Underrepresentation of female authors in research publications is prevalent, but it is unclear whether this is attributable to sex disparities in research conduct or authorship practices. Case reports are a poorly understood component of the biomedical corpus, and the production of anecdotal observations is not confounded by factors associated with disparities in female representation in research publications. Whether female authorship disparities exist in nonresearch publications of clinical information is unknown.
    Objectives: To examine the authorship of case reports and elucidate factors associated with sex disparity.
    Design and Setting: Cross-sectional study of all case reports published by US authors in 2014 and 2015 indexed in PubMed performed from July 2015 to July 2018.
    Main Outcomes and Measures: The primary outcome measure was the proportion of female first authors. The secondary outcome measures were the proportion of female last authors and female authorship representation among different clinical specialties.
    Results: Bibliometric data was abstracted from 20 427 case reports published across 2538 journals. A total of 7252 (36%) and 4825 (25%) case reports had a female first and last author, respectively. In comparison, 44% and 34% of US trainees and physicians, respectively, were female in 2015. Among adult case reports, female authorship was more prevalent in academic environments compared with community settings (34.0% vs 28.2% for female first authors and 23.4% vs 19.7% for female last authors). Across states, the proportions of female first authors and last authors were universally less than the proportions of female trainees and active female physicians, respectively. Female first authorship was associated with larger author teams (odds ratio [OR], 1.02; 95% CI, 1.01-1.03), an academic affiliation (OR, 1.16; 95% CI, 1.06-1.27), and a female last author (OR, 1.58; 95% CI, 1.47-1.70). Relative to general internal medicine, specialties dominated by male clinicians were less frequently associated with female first authors. Several exceptions displaying a relatively equivalent tendency for male and female first authorship included oncology (OR, 0.97; 95% CI, 0.81-1.16), ophthalmology (OR, 0.87; 95% CI, 0.72-1.05), and radiation oncology (OR, 0.94 95% CI, 0.56-1.56).
    Conclusions and Relevance: The underrepresentation of women among first and last authors in publications of case reports underscores the pervasiveness of sex disparities in medicine. Collaboration and female mentors may be critical instruments in upsetting longstanding practices associated with sex bias. Not all clinical specialties were associated with lower-than-expected female authorship, and further exploration of specialty-specific norms in publication and mentorship may elucidate specific barriers to female authorship.
    DOI:  https://doi.org/10.1001/jamanetworkopen.2019.5000
  14. J Hypertens. 2019 May 06.
       OBJECTIVE: Hypertension, a major cardiovascular risk factor, may reach a global prevalence of 1.56 billion by 2025. Much research has been conducted in this field, but few bibliometric studies have been performed. We aimed to analyse the changes in scientific output relating to hypertension over the past two decades.
    METHODS: We analysed, via PubMed and Web of Science, the scientific output relating to hypertension from 1997 to 2016. Quantitative (number of publications) and citation (top 1 and 10%) analyses were performed for output globally and by major countries/regions, with a particular focus on the European Union.
    RESULTS: In total, 100 789 articles relating to hypertension were identified in Web of Science. The number of publications increased by 52.7% (3989 in 1997, 6092 in 2016). Of the 100 789 articles, 38% had authors from the European Union, 32.1% had authors from the USA, and 26.7% had authors from Asia, with a marked increase in contributions from China over the period analysed. Articles appeared in more than 400 journals and were cited nearly 2 556 000 times. The relative weights of different research fields have also changed over time.
    CONCLUSION: Combined use of PubMed and Web of Science enabled robust bibliometric analysis of the studies into hypertension published in the period 1997-2016, including assessment of the contributions from major countries, particularly those in the European Union. This study also allowed us to validate our methodology, which could be used to evaluate research policies and to promote international cooperation.This is an open access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal. http://creativecommons.org/licenses/by-nc-nd/4.0.
    DOI:  https://doi.org/10.1097/HJH.0000000000002143
  15. Oncotarget. 2019 May 14. 10(35): 3267-3275
      The global outputs of annual publication in long non-coding RNAs (lncRNAs) and chemotherapeutic resistance research exponentially increased from 2 in 2008 to 176 in 2017. Using Java application CiteSpace V and VOSviewer, this study assessed the publication model of lncRNAs and chemoresistance by bibliometric analysis. Totally, 2883 authors contributed 528 publications of lncRNAs and chemoresistance in 215 academic journals in the recent decade (2008-2018). Oncotarget in the 215 academic journals published the highest number of publications (60). China had the highest number of publication outputs (358). The leading institute was Nanjing Medical University. Wang Y was the most influential author (13 counts). Gupta RA had the most cited documents (87 counts). "Gene expression" and "poor prognosis" were identified as the hotspots. "Cancer stem cell", "HOTAIR" and "UCA1" were the frontiers of the fields in recent years. The increase of publications on lncRNAs and chemotherapeutic resistance will continue in the next years. HOTAIR and UCA1 with multiple roles in drug resistance may offer big opportunities for targeted chemoresistance in cancer therapy. These results may help us discover and explain the possible underlying laws of the subject.
    Keywords:  bibliometric analysis; chemotherapeutic resistance; citespace; lncRNA
    DOI:  https://doi.org/10.18632/oncotarget.26938
  16. BMC Health Serv Res. 2019 May 28. 19(1): 340
       BACKGROUND: Nursing and midwifery research activity is an important indicator of the quality of healthcare services and the status of nursing profession. The main aim of this study was to assess the research activity in nursing and midwifery field in Arab countries.
    METHOD: The current study implemented bibliometric method using Scopus database. The search strategy used country affiliation or journal name or keywords as a strategy to retrieve the required documents. The study period was from 1950 to2017. Analysis included a presentation of bibliometric indicators and VOSviewer mapping of the retrieved data.
    RESULT: 2935 documents were retrieved making up less than 1% of global nursing and midwifery research output. Of the retrieved documents, 25% were published in high rank (first quartile = Q1) journals. The majority (56.7%) of the retrieved documents were published in the last five years of the study period. The retrieved documents received an average of 6.9 citations per document with an h-index of 47. The total number of authors who took part in publishing the retrieved documents was 10,572, giving an average of 3.6 authors per article. Jordan ranked first in research output. Researchers from Jordan took part in over than one third (1023; 34.9%) of the retrieved documents. Lebanon (35.5%) ranked first in the percentage of documents published in Q1 journals. The United Arab Emirates ranked first in the percentage (67.4%) of publications with international authors. The most active journal involved in publishing nursing research from Arab countries was Life Science Journal (158; 5.4%). The University of Jordan was the most productive institution while the American University of Beirut ranked first in the percentage (36.9%) of documents published in Q1 journals. Author keyword analysis and10 most cited articles showed that non-communicable diseases and nursing education were the focus of nursing research in Arab countries.
    CONCLUSIONS: Nursing and midwifery research activity in Arab countries has dramatically increased especially over the past five years. Despite this, nursing research is still in its infancy, lagging in quantity and quality compared to developed countries.
    Keywords:  Arab countries; Bibliometric analysis; Midwifery; Nursing
    DOI:  https://doi.org/10.1186/s12913-019-4178-y
  17. World Neurosurg. 2019 May 28. pii: S1878-8750(19)31456-1. [Epub ahead of print]
       BACKGROUND: Convection-enhanced delivery (CED) overcomes the blood brain barrier to deliver therapy within the central nervous system. Our aim was to evaluate citation and other bibliometric characteristics of the 100 most-cited articles about CED to the brain in order to better understand the state of current research efforts in the field.
    METHODS: Elsevier's Scopus database was searched for the 100 most-cited articles that focussed on CED to the brain. Articles were dichotomized as either primarily basic science (BSc) or clinical (CL) articles. Various bibliometric parameters were summarized, and BSc and CL articles were compared.
    RESULTS: Of the 100 most-cited articles, 64 (64%) were BSc and 36 (36%) were CL articles. The most common indications reported were brain tumors (59%) and Parkinson's disease (5%). Overall median values were as follows: citation count, 102 (range, 70-933); citation rate per year, 9.0 (3.7-49.4); number of authors 5 (1-25); publication year 2006 (1994-2015). Articles were published in a total of 48 different journals, and predominately originated in the US (n=78, 78%). BSc and CL articles were statistically comparable in terms of bibliometric parameters.
    CONCLUSIONS: In the 100 most-cited articles about CED to the brain, there was a greater number of BSc articles compared to CL articles, however they were comparable with respect to the reported bibliometric parameters. Given the peak year of publication of these articles was over a decade ago, we anticipate the field will shift towards greater CL articles once effective therapies to be delivered via CED are discovered.
    Keywords:  . Convection-enhanced delivery; CED; bibliometric; brain; glioma; most-cited
    DOI:  https://doi.org/10.1016/j.wneu.2019.05.179
  18. Environ Pollut. 2019 May 20. pii: S0269-7491(19)31301-6. [Epub ahead of print]252(Pt A): 74-83
      The application of nanoscale zero-valent iron is one of the most widely used remediation technologies; however, the potential environmental risks of this technology are largely unknown. In order to broaden the knowledge on this subject, the present work consists of a bibliometric study of all of publications related to the toxicity of zero-valent iron nanoparticles used in soil remediation available from the Scopus (Elsevier) and Web of Science (Thompson Reuters) databases. This study presents a temporal distribution of the publications, the most cited articles, the authors who have made the greatest contribution to the theme, and the institutions, countries, and scientific journals that have published the most on this subject. The use of bibliometrics has allowed for the visualization of a panorama of the publications, providing an appropriate analysis to guide new research towards an effective contribution to science by filling the existing gaps. In particular, the lack of studies in several countries reveals a promising area for the development of further research on this topic.
    Keywords:  Indicators; Review; Scopus; Web of science; nZVI
    DOI:  https://doi.org/10.1016/j.envpol.2019.05.092