A global exploratory comparison of country self-citations 1996-2019

From Solo to Collaborative: The Global Increase in Neuroscience Authors Over Two Decades

The increase in the number of authors per article is a well-documented phenomenon across various academic disciplines. While prior studies have examined this trend in specific fields and countries, they in most cases did not compare the increase in the number of authors between countries. While it has previously shown that the number of authors in neuroscience publications has risen in the G10 countries, no study has yet addressed whether it reflects a global trend in the field. To address this gap, we quantified the global trend in the number of authors in neuroscience publications from 2001 to 2022. Our findings reveal a consistent increase in authorship across nearly all the countries examined. Italy ranks highest in terms of average authorship per article, while Ukraine ranks the lowest. On the other hand, China shows the largest increase in authorship over the years, followed by Norway and Egypt. South Korea is the only country showing a slight decreasing trend rather than growth. These results contribute to a better understanding of authorship patterns in neuroscience and can stimulate further investigations on the reasons behind such an increase in terms of socio-economic factors, the need for collaborative efforts in some fields, or, on the negative side, the effect of utilitarian reasons to meet career evaluation criteria.

Self-citation pattern among world's top 2 % of the scientists

Although self-citation is a common practice among scholars, its impact and significance remain under scrutiny within the academic community. The current study aimed to provide a detailed analysis and ranking of the top 2 % scientists on self-citation, ranked by Stanford University researchers. Data extraction and organisation were performed between January and February 2024. Self-citation percentages were collected for authors belonging to 20 fields and 174 subfields using Excel spreadsheets. Entities were categorised into quartiles based on their self-citation percentages and rankings were assigned accordingly. Comparative analyses were conducted to assess the impact of self-citations on overall rankings. The study focused on data published by a group of researchers from Stanford University regarding the top 2 % of researchers, analysing the career-long records of 204,643 scholars and 210,198 scholars for the most recent year, 2022. Notably, in the single-year analysis, among the top 20 countries, approximately eight (40 %) exhibited self-citation percentages exceeding the average of 25.96 %. The self-citation percentages ranged from 4.47 % in Economics and Business to 20.88 % in Physics and Astronomy. Regarding career-long analysis, the percentage of self-citations ranged from 22.84 % in Poland to 41.31 % in Armenia, with significant drop in rankings among most entities when self-citations were excluded. These findings highlight the dramatic impact of self-citation exclusion on the rankings of the top 2 % of the researchers, underscoring the critical importance of accounting for self-citation in ranking assessments.

The increasing authorship trend in neuroscience: A scientometric analysis across 11 countries

Previous studies have demonstrated an increasing trend of the number of authors across various fields over the years. This trend has been attributed to the necessity for larger collaborations and, at times, to ethical issues regarding authorship attribution. Our study focuses on the evolution of authorship trends in the field of Neuroscience. We conducted our analysis based on a dataset containing 580,782 neuroscience publications produced from 2000 to 2022, focusing on the publications within the Group of ten (G10) countries. Using a matrix-based methodology, we extracted and analyzed the average number of authors per country. Our findings reveal a consistent rise in authorship across all G10 countries over the past two decades. Italy emerged with the highest average number of authors, while France stood out for experiencing the most significant increase, particularly in the last decade. The countries with the lowest number of authors per publication were the USA, UK and Canada. Differences between countries could result from variations in the size of collaboration between researchers in different countries. Additionally, these differences may depend on utilitarian considerations aimed at receiving higher scores in the individual evaluation of their own work. We propose that a normalization procedure for the number of authors should be implemented to ensure a fair evaluation of researchers.