The 100 most-cited articles in COVID-19: a bibliometric analysis.

Corona virus disease 2019 (COVID-19) pandemic, sparked by the emergence of a novel coronavirus in early 2020, has prompted a surge in published articles. This study aims to systematically analyse the characteristics and trends of impactful research in the field. The 100 most-cited publications associated with COVID-19 were identified by two independent reviewers using the 'Web of Science' database across all available journals up to the year 2023. Data collected include country, citation count, subject, level of evidence (using Oxford Centre for Evidence-Based Medicine System 2011), impact factor, funding, and study design. We identified 394 038 publications, and the 100 most-cited publications were ranked. These were cited by a total of 283 034 articles (median citation = 767), median impact factor of 66.9 and 72 articles with fundings. China (n = 44), USA (n = 19), and UK (n = 13) were the three highest contributors (n = 220 505). Most articles were level 5 evidence (n = 48), followed by level 3 (n = 28), 4 (n = 14), 2 (n = 7), and 1 (n = 3). The main subjects were mechanism of action and structures of SARS-CoV-2 virus (n = 18) and impact of COVID-19 on public health (n = 18). Publications in 2022 and 2023 predominantly focused on the impact of COVID-19. Majority of the highly cited studies were of low-to-moderate quality, with only 10 consisting of randomized controlled trials or systematic reviews with or without meta-analysis. These findings reflect a growing interest in understanding the impact of COVID-19 pandemic on public and mental health. This analysis found the potential for future double-blinded randomized controlled trials to validate existing findings.

Obex position is associated with syringomyelia and use of posterior fossa decompression among patients with Chiari I malformation.

OBJECTIVE: Chiari I malformation (CM-I) has traditionally been defined by measuring the position of the cerebellar tonsils relative to the foramen magnum. The relationships of tonsillar position to clinical presentation, syringomyelia, scoliosis, and the use of posterior fossa decompression (PFD) surgery have been studied extensively and yielded inconsistent results. Obex position has been proposed as a useful adjunctive descriptor for CM-I and may be associated with clinical disease severity. METHODS: A retrospective chart review was performed of 442 CM-I patients with MRI who presented for clinical evaluation between 2003 and 2018. Clinical and radiological variables were measured for all patients, including presence/location of headaches, Chiari Severity Index (CSI) grade, tonsil position, obex position, clival canal angle, pB-C2 distance, occipitalization of the atlas, basilar invagination, syringomyelia, syrinx diameter, scoliosis, and use of PFD. Radiological measurements were then used to predict clinical characteristics using regression and survival analyses, with performing PFD, the presence of a syrinx, and scoliosis as outcome variables. RESULTS: Among the radiological measurements, tonsil position, obex position, and syringomyelia were each independently associated with use of PFD. Together, obex position, tonsil position, and syringomyelia (area under the curve [AUC] 89%) or obex position and tonsil position (AUC 85.4%) were more strongly associated with use of PFD than tonsil position alone (AUC 76%) (Pdiff = 3.4 × 10-6 and 6 × 10-4, respectively) but were only slightly more associated than obex position alone (AUC 82%) (Pdiff = 0.01 and 0.18, respectively). Additionally, obex position was significantly associated with occipital headaches, CSI grade, syringomyelia, and scoliosis, independent of tonsil position. Tonsil position was associated with each of these traits when analyzed alone but did not remain significantly associated with use of PFD when included in multivariate analyses with obex position. CONCLUSIONS: Compared with tonsil position alone, obex position is more strongly associated with symptomatic CM-I, as measured by presence of a syrinx, scoliosis, or use of PFD surgery. These results support the role of obex position as a useful radiological measurement to inform the evaluation and potentially the management of CM-I.