ABSTRACT
With the global spread of the COVID-19 pandemic, scientists from various disciplines responded quickly to this historical public health emergency. The sudden boom of COVID-19-related papers in a short period of time may bring unexpected influence to some commonly used bibliometric indicators. By a large-scale investigation using Science Citation Index Expanded and Social Sciences Citation Index, this brief communication confirms the citation advantage of COVID-19-related papers empirically through the lens of Essential Science Indicators' highly cited paper. More than 8% of COVID-19-related papers published during 2020 and 2021 were selected as Essential Science Indicators highly cited papers, which was much higher than the set global benchmark value of 1%. The citation advantage of COVID-19-related papers for different Web of Science categories/countries/journal impact factor quartiles was also demonstrated. The distortions of COVID-19-related papers' citation advantage to some bibliometric indicators such as journal impact factor were discussed at the end of this brief communication.
ABSTRACT
Background The COVID-19 pandemic seriously affects human health and life. COVID-19 has been reportedly associated with a high risk of thrombotic events, which are closely associated with stroke. Objective To assess the effect and possible mechanism of COVID-19 on stroke morbidity, providing a reliable theoretical basis for scientific prevention and treatment of COVID-19 in stroke. Methods We searched databases of Web of Science, PubMed, EmBase, Cochrane Library, CNKI and Wanfang Data for cohort studies and case-control studies related to COVID-19 and stroke published from December 2019 to January 2022. Two researchers conducted literature screening and data extraction separately. The Newcastle-Ottawa Scale was used to assess the quality of included studies. Meta-analysis was used to evaluate the impact of COVID-19 on stroke mortality. Funnel plot was used to evaluate the potential publication bias. Results A total of 18 studies were included, 12 of them were of good quality, and other 6 were of fair quality. Meta-analysis showed that stroke patients with COVID-19 had higher mortality 〔RR=4.16, 95%CI(2.82, 6.13), P<0.000 01〕, prolonged prothrombin time (PT) 〔MD=0.78, 95%CI (0.35, 1.20), P=0.000 3〕, higher D-dimer level 〔MD=1.34, 95%CI(0.83, 1.84), P<0.000 01〕 and higher NIHSS score 〔MD=6.66, 95%CI (4.54, 8.79), P<0.000 01〕, as well as younger age 〔MD=-2.04, 95%CI(-3.48, -0.61), P=0.005〕 than those without COVID-19. There was no statistically significant difference in activated partial thromboplastin time between stroke patients with and without COVID-19 〔MD=2.51, 95%CI(-2.69, 7.71), P=0.34〕. Funnel plot assessing potential publication bias in the impact of COVID-19 on stroke mortality was basically symmetrical. Conclusion COVID-19 could increase the risk of stroke mortality, which may be related to alterations in the coagulation system manifested by abnormal PT and D-dimer level and so on. And the outcomes of stroke patients with COVID-19 were associated with age and NIHSS score at admission. © 2023 Chinese General Practice. All rights reserved.
ABSTRACT
Background The COVID-19 pandemic seriously affects human health and life. COVID-19 has been reportedly associated with a high risk of thrombotic events, which are closely associated with stroke. Objective To assess the effect and possible mechanism of COVID-19 on stroke morbidity, providing a reliable theoretical basis for scientific prevention and treatment of COVID-19 in stroke. Methods We searched databases of Web of Science, PubMed, EmBase, Cochrane Library, CNKI and Wanfang Data for cohort studies and case-control studies related to COVID-19 and stroke published from December 2019 to January 2022. Two researchers conducted literature screening and data extraction separately. The Newcastle-Ottawa Scale was used to assess the quality of included studies. Meta-analysis was used to evaluate the impact of COVID-19 on stroke mortality. Funnel plot was used to evaluate the potential publication bias. Results A total of 18 studies were included, 12 of them were of good quality, and other 6 were of fair quality. Meta-analysis showed that stroke patients with COVID-19 had higher mortality 〔RR=4.16, 95%CI(2.82, 6.13), P<0.000 01〕, prolonged prothrombin time (PT) 〔MD=0.78, 95%CI (0.35, 1.20), P=0.000 3〕, higher D-dimer level 〔MD=1.34, 95%CI(0.83, 1.84), P<0.000 01〕 and higher NIHSS score 〔MD=6.66, 95%CI (4.54, 8.79), P<0.000 01〕, as well as younger age 〔MD=-2.04, 95%CI(-3.48, -0.61), P=0.005〕 than those without COVID-19. There was no statistically significant difference in activated partial thromboplastin time between stroke patients with and without COVID-19 〔MD=2.51, 95%CI(-2.69, 7.71), P=0.34〕. Funnel plot assessing potential publication bias in the impact of COVID-19 on stroke mortality was basically symmetrical. Conclusion COVID-19 could increase the risk of stroke mortality, which may be related to alterations in the coagulation system manifested by abnormal PT and D-dimer level and so on. And the outcomes of stroke patients with COVID-19 were associated with age and NIHSS score at admission. © 2023 Chinese General Practice. All rights reserved.