Predictors of Citations in Neurosurgical Research: A 5-Year Follow-Up

Citation of updated and co-published Cochrane Methodology Reviews

BACKGROUND

To evaluate the number of citations for Cochrane Methodology Reviews after they have been updated or co-published in another journal, and the effect of co-publishing the review on the co-publishing journal's impact factor (IF).

METHODS

We identified all Cochrane Methodology Reviews published in the Cochrane Database of Systematic Reviews (CDSR) before 2018 and searched for co-published versions in the Web of Science Core Collection database up to 16 August 2022. The included reviews were in two cohorts: those that had been published and updated in CDSR and those that had been published in CDSR and co-published in another journal. The primary outcome measured the citation number to updated and original reviews in the first five years after publication of the updated review, and assessed the citation number of co-published and non-co-published reviews in the first five years after publication of the co-published version. The secondary outcome was the ratio of an adjusted IF and the actual IF of the co-publishing journal.

RESULTS

Eight updated and six original reviews were identified for the updated cohort of reviews, and four co-published reviews were included in the co-published cohort. The original reviews continued to be cited after the update was published but the median for the total number of citations was non-significantly higher for the updated reviews than for their original version[161 (Interquartile range (IQR) 85, 198) versus 113 (IQR 15, 433)]. The median number of total citations [362 (IQR 179, 840) versus 145 (IQR 75, 445)] and the median number of citations to the review in the first five years after co-publication combined and in each of those years was higher in the co-published group than in the non-co-published group. One of the three journals that co-published Reviews in the first year and two journals in the second year had a lower IF after co-publication.

CONCLUSIONS

Earlier versions of Cochrane Methodology Reviews continue to be cited after an update is published, which raises doubts about whether those citing are using the most recent evidence or are aware of the update. Co-publication facilitates broader application and dissemination of Cochrane methodology evidence.

Predictors of Citations for Original Research in Ophthalmology

There is a dearth of literature on factors associated with citation of publications in ophthalmology. We investigated predictors of citations for original ophthalmologic research articles based on author, study, and journal characteristics. In accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PRISMA), we extracted articles that studied the leading cause of vision impairment in the United States (cataract, diabetic retinopathy, age-related macular degeneration, and glaucoma) and were published in the top fifteen ophthalmology journals with the highest impact factors that accepted original research. Descriptive statistics, one-way analysis of variance (ANOVA) tests, and negative binomial regression were used to compare citation counts based on author, study, and journal characteristics. In this study, author research productivity, journal impact factor, study funding, and location in high-income countries were predictors of increased citation in ophthalmology.

Contribution of Saudi Neurosurgeons to the International Neurosurgical Literature: a Bibliometric Analysis of Trends Over the Last Three Decades

This review is a bibliometric analysis of the contribution of neurosurgeons from the Kingdom of Saudi Arabia (KSA) to the international neurosurgical literature over the last three decades. The study aimed at determining changes in publication trends over time and assessing the impact of these changes on citation numbers. All publications in the PubMed-indexed neurosurgical journals that were authored by at least one Saudi neurosurgeon were selected. The articles were divided into two study groups according to publication year whether during the last decade (2011- 2020) or the previous two decades (1991- 2010). Changes in publication trends were determined by comparing the bibliometric characteristics of the articles in both groups. The impact of the changes on citation numbers was assessed by correlating the annual citation rates for the articles with their bibliometric qualities. A total of 352 publications were suitable for the review (200 articles published during 2011- 2020, and 152 during 1991- 2010). Temporal changes in the publishing journals and first authors' centres and regions were observed. The articles that were published in the last decade were associated with a significantly higher annual publication rate, a greater number of authors, centres, and countries, and a larger sample size compared to those published in the previous two decades. They also had a lower percentage of Saudi total and first authorship as well as a smaller proportion of case reports. The annual citation rate was significantly impacted by the duration from publication, sample size, and study type during both study periods. However, only during the last decade, the annual citation rate was positively influenced by the journal's impact factor, number of authors, centres, countries, and percentage of Saudi authorship. We conclude that KSA neurosurgeons' contribution to international neurosurgical journals had increased considerably over the last decade. The publications were authored by neurosurgeons from a wider range of centres and regions than in the past. A bigger portion of publications had become more multi-authored, multi-centred, and multi-national as well as reported larger sample sizes and lesser rates of case reports. The changes in publication trends correlated positively with the articles' annual citation rates. The findings could be considered encouraging.