Temporal trends in the impact factor of European versus USA biomedical journals

Temporal Trends (1999-2015) in the Impact Factor of Biomedical Journals Published by US and EU Scientific Societies

OBJECTIVE

The impact factor has emerged as the most popular index of scientific journals' resonance. In this study we aimed to examine the impact factor trends of journals published by scientific bodies in the United States of America (USA) and Europe (EU).

METHODS

We randomly chose 11 categories of Journal of Citation Reports and created three research classes: clinical medicine, laboratory medicine, and basic science. The impact factor values for the years 1999-2015 were abstracted, and the impact factor of US and EU journals was studied through the years.

RESULTS

A total of 265 journals were included in the final analysis. The impact factor of US journals was higher than that of EU journals throughout the study period. In addition, for both US and EU journals the median impact factor increased throughout the study period. The rate of annual change in the impact factor throughout the study period was lower for US than EU journals (1.85% versus 3.55%, P=0.019). A higher median annual increase was seen in the impact factor during the period 1999-2008 compared to the period 2009-2015 for both US (P<0.001) and EU (P=0.001) journals. In fact, during the second period the US median impact factor value did not show significant changes (P=0.31), while the EU median impact factor continued to increase (P<0.001).

CONCLUSION

The impact factor of EU journals increased at a significantly higher rate than and approached that of the US journals during the last 16 years.

The Journal Impact Factor: Moving Toward an Alternative and Combined Scientometric Approach

The Journal Impact Factor (JIF) is a single citation metric, which is widely employed for ranking journals and choosing target journals, but is also misused as the proxy of the quality of individual articles and academic achievements of authors. This article analyzes Scopus-based publication activity on the JIF and overviews some of the numerous misuses of the JIF, global initiatives to overcome the 'obsession' with impact factors, and emerging strategies to revise the concept of the scholarly impact. The growing number of articles on the JIF, most of which are in English, reflects interest of experts in journal editing and scientometrics toward its uses, misuses, and options to overcome related problems. Solely displaying values of the JIFs on the journal websites is criticized by experts as these average metrics do not reflect skewness of citation distribution of individual articles. Emerging strategies suggest to complement the JIFs with citation plots and alternative metrics, reflecting uses of individual articles in terms of downloads and distribution of related information through social media and networking platforms. It is also proposed to revise the original formula of the JIF calculation and embrace the concept of the impact and importance of individual articles. The latter is largely dependent on ethical soundness of the journal instructions, proper editing and structuring of articles, efforts to promote related information through social media, and endorsements of professional societies.

A bibliometric analysis of diets and breast cancer research

Breast cancer is the most common cancer among women worldwide. The primary aim of this work was to provide an in-depth evaluation of research publications in the field of diets and breast cancer. The impact of economic outcome on national academic productivity was also investigated. Data were retrieved using Pubmed for English-language publications. The search included all research for which articles included words relating to "diets and breast cancer". Population and national income data were obtained from publicly available databases. Impact factors for journals were obtained from Journal Citation Reports® (Thomson Scientific). There were 2,396 publications from 60 countries in 384 journals with an impact factor. Among them, 1,652 (68.94%) publications were Original articles. The United States had the highest quantity (51% of total) and highest of mean impact factor (8.852) for publication. Sweden had the highest productivity of publication when adjusted for number of population (6 publications per million population). Publications from the Asian nation increased from 5.3% in 2006 to 14.6% in 2012. The Original article type was also associated with geography (p<0.001; OR=2.183; 95%CI=1.526-3.123), Asian countries produced more proportion of Original articles (82%) than those of rest of the world (67.6%). Diets and breast cancer-associated research output continues to increase annually worldwide including publications from Asian countries. Although the United States produced the most publications, European nations per capita were higher in publication output.

Impact of article language in multi-language medical journals--a bibliometric analysis of self-citations and impact factor

Background

In times of globalization there is an increasing use of English in the medical literature. The aim of this study was to analyze the influence of English-language articles in multi-language medical journals on their international recognition – as measured by a lower rate of self-citations and higher impact factor (IF).

Methods and Findings

We analyzed publications in multi-language journals in 2008 and 2009 using the Web of Science (WoS) of Thomson Reuters (former Institute of Scientific Information) and PubMed as sources of information. The proportion of English-language articles during the period was compared with both the share of self-citations in the year 2010 and the IF with and without self-citations. Multivariable linear regression analysis was performed to analyze these factors as well as the influence of the journals‘ countries of origin and of the other language(s) used in publications besides English.

We identified 168 multi-language journals that were listed in WoS as well as in PubMed and met our criteria. We found a significant positive correlation of the share of English articles in 2008 and 2009 with the IF calculated without self-citations (Pearson r=0.56, p = <0.0001), a correlation with the overall IF (Pearson r = 0.47, p = <0.0001) and with the cites to years of IF calculation (Pearson r = 0.34, p = <0.0001), and a weak negative correlation with the share of self-citations (Pearson r = -0.2, p = 0.009). The IF without self-citations also correlated with the journal‘s country of origin – North American journals had a higher IF compared to Middle and South American or European journals.

Conclusion

Our findings suggest that a larger share of English articles in multi-language medical journals is associated with greater international recognition. Fewer self-citations were found in multi-language journals with a greater share of original articles in English.

Financial, nonfinancial and editors' conflicts of interest in high-impact biomedical journals

PURPOSE

To assess financial, nonfinancial and editors' conflicts of interest (COI) disclosure policies among the most influential biomedical journals publishing original research.

MATERIALS AND METHODS

We conducted a cross-sectional study of 399 high-impact biomedical journals in 27 biomedical categories of the Journal Citation Reports (JCR) in December 2011. Information relevant to COI and requirements for disclosures that was publicly available on journal websites was collected.

RESULTS

While financial COI disclosures were required by 358 (89.7%) and nonfinancial by 280 (70.2%) journals, 155 (38.8%) required editors' disclosures. Journals in the first decile of the JCR classification scored significantly higher than those in the second decile for all disclosure policies. Ninety (22.6%) journals were published by Elsevier and 59 (14.8%) by Wiley-Blackwell, with Elsevier scoring significantly better in financial disclosure policies (P = 0.022). Clinical journals scored significantly higher than basic journals for all disclosure policies. No differences were observed between open-access (n = 25) and nonopen-access (n = 374) journals for any type of disclosure. Somewhat incoherently, authors' disclosure statements were included in some published manuscript in 57.1% of journals without any COI disclosure policies.

CONCLUSIONS

Authors' financial COI disclosures were required by about 90% of high-impact clinical and basic journals publishing original research. Unlike recent studies showing a significantly lower prevalence of nonfinancial compared with financial disclosures, the former were required by about 70% of journals, suggesting that editors are increasingly concerned about nonfinancial competing interests. Only 40% of journals required disclosure of editors' COI, in conflict with the recommendations of the most influential editors' associations.

The evolution of academic performance in nine subspecialties of internal medicine: an analysis of journal citation reports from 1998 to 2010

BACKGROUND

Internal medicine includes several subspecialties. This study aimed to describe change trend of impact factors in different subspecialties of internal medicine during the past 12 years, as well as the developmental differences among each subspecialty, and the possible influencing factors behind these changes and differences.

METHODS

Nine subspecialties of internal medicine were chosen for comparison. All data were collected from the Science Citation Index Expanded and Journal Citation Reports database.

RESULTS

(1) Journal numbers in nine subspecialties increased significantly from 1998 to 2010, with an average increment of 80.23%, in which cardiac and cardiovascular system diseases increased 131.2% rank the first; hematology increased 45% rank the least. (2) Impact Factor in subspecialties of infectious disease, cardiac and cardiovascular system diseases, gastroenterology and hepatology, hematology, endocrinology and metabolism increased significantly (p<0.05), in which gastroenterology and hepatology had the largest increase of 65.4%. (3) Journal impact factor of 0-2 had the largest proportion in all subspecialties. Among the journals with high impact factor (IF>6), hematology had the maximum proportion of 10%, nephrology and respiratory system disease had the minimum of 4%. Among the journal with low impact factor (IF<2), journal in nephrology and allergy had the most (60%), while endocrinology and metabolism had the least (40%). There were differences in median number of IF among the different subspecialties (p<0.05), in which endocrinology and metabolism had the highest, nephrology had the lowest. (4) The highest IF had a correlation with journal numbers and total paper numbers in each field.

CONCLUSION

The IF of internal medicine journals showed an increasingly positive trend, in which gastroenterology and hepatology increase the most. Hematology had more high IF journals. Endocrinology and metabolism had higher average IF. Nephrology remained the lowest position. Numbers of journals and total papers were associated with the highest IF.

Biomedical publications profile and trends in gulf cooperation council countries

OBJECTIVES

There is a dearth of studies examining the relationship between research output and other socio-demographic indicators in the Gulf Cooperation Council (GCC) countries (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and the United Arab Emirates). The three interrelated aims of this study were, first, to ascertain the number of biomedical publications in the GCC from 1970 to 2010; second, to establish the rate of publication according population size during the same period and, third, to gauge the relationship between the number of publications and specific socio-economic parameters.

METHODS

The Medline database was searched in October 2010 by affiliation, year and publication type from 1970 to 2010. Data obtained were normalised to the number of publications per million of the population, gross domestic product, and the number of physicians in each country.

RESULTS

The number of articles from the GCC region published over this 40 year period was 25,561. Saudi Arabia had the highest number followed by Kuwait, UAE, and then Oman. Kuwait had the highest profile of publication when normalised to population size, followed by Qatar. Oman is the lowest in this ranking. Overall, the six countries showed a rising trend in publication numbers with Oman having a significant increase from 1990 to 2005. There was a significant relationship between the number of physicians and the number of publications.

CONCLUSION

The research productivity from GGC has experienced complex and fluctuating growth in the past 40 years. Future prospects for increasing research productivity are discussed with particular reference to the situation in Oman.