Background: The research community reacted rapidly to the emergence of COVID-19. We aimed to assess characteristics of journal articles, preprint articles, and registered trial protocols about COVID-19 and its causal agent SARS-CoV-2. Methods: We analyzed characteristics of journal articles with original data indexed by March 19, 2020, in World Health Organization (WHO) COVID-19 collection, articles published on preprint servers medRxiv and bioRxiv by April 3, 2010. Additionally, we assessed characteristics of clinical trials indexed in the WHO International Clinical Trials Registry Platform (WHO ICTRP) by April 7, 2020. Results: Among the first 2118 articles on COVID-19 published in scholarly journals, 533 (25%) contained original data. The majority was published by authors from China (75%) and funded by Chinese sponsors (75%); a quarter was published in the Chinese language. Among 312 articles that self-reported study design, the most frequent were retrospective studies (N = 88; 28%) and case reports (N = 86; 28%), analyzing patients' characteristics (38%). Median Journal Impact Factor of journals where articles were published was 5.099. Among 1088 analyzed preprint articles, the majority came from authors affiliated in China (51%) and were funded by sources in China (46%). Less than half reported study design; the majority were modeling studies (62%), and analyzed transmission/risk/prevalence (43%). Of the 927 analyzed registered trials, the majority were interventional (58%). Half were already recruiting participants. The location for the conduct of the trial in the majority was China (N = 522; 63%). The median number of planned participants was 140 (range: 1 to 15,000,000). Registered intervention trials used highly heterogeneous primary outcomes and tested highly heterogeneous interventions; the most frequently studied interventions were hydroxychloroquine (N = 39; 7.2%) and chloroquine (N = 16; 3%).

Celecoxib may improve clinical symptoms, alleviate pain and contribute to little or no difference in physical function compared with placebo. Celecoxib was associated with fewer numbers of participant withdrawals. Results for incidence of gastroduodenal ulcers (≥ 3 mm) and short-term serious adverse events were uncertain; however, there were few reported events for either.Celecoxib may slightly improve clinical symptoms compared with tNSAIDs. Results for reduced pain and improved physical function were uncertain. Particpants taking celecoxib had lower incidence of gastroduodenal ulcers (≥ 3 mm) and there were fewer withdrawals from trials. Results for cardiovascular events and short-term serious adverse events were also uncertain.Uncertainty about the rate of cardiovascular events between celecoxib and tNSAIDs could be due to risk of bias; another factor is that these were small, short-term trials. It has been reported previously that both celecoxib and tNSAIDs increase cardiovascular event rates. Our confidence in results about harms is therefore low. Larger head-to-head clinical trials comparing celecoxib to other tNSAIDs is needed to better inform clinical practice.

Background A crucial element in the systematic review (SR) methodology is the appraisal of included primary studies, using tools for assessment of methodological quality or risk of bias (RoB). SR authors can conduct sensitivity analyses to explore whether their results are sensitive to exclusion of low quality studies or a high RoB. However, it is unknown which tools do SR authors use for assessing quality/RoB, and how they set threshold for quality/RoB in sensitivity analyses. The aim of this study was to assess quality/RoB assessment tools, the types of sensitivity analyses and quality/RoB thresholds for sensitivity analyses used within SRs published in high-impact pain/anesthesiology journals. Methods This was a methodological study. We analyzed SRs published from January 2005 to June 2018 in the 25% highest-ranking journals within the Journal Citation Reports (JCR) “Anesthesiology” category. We retrieved the SRs from PubMed. Two authors independently screened records, full texts, and extracted data on quality/RoB tools and sensitivity analyses. We extracted data about quality/RoB tools, types of sensitivity analyses and the thresholds for quality/RoB used in them. Results Out of 678 analyzed SRs, 513 (76%) reported the use of quality/RoB assessments. The most commonly reported tools for assessing quality/RoB in the studies were the Cochrane tool for risk of bias assessment (N = 251; 37%) and Jadad scale (N = 99; 15%). Meta-analysis was conducted in 451 (66%) of SRs and sensitivity analysis in 219/451 (49%). Most commonly, sensitivity analysis was conducted to explore the influence of study quality/RoB (90/219; 41%) on the results. Quality/RoB thresholds used for sensitivity analysis for those studies were clearly reported in 47 (52%) articles that used them. The quality/RoB thresholds used for sensitivity analyses were highly heterogeneous and inconsistent, even when the same tool was used. Conclusions A quarter of SRs reported using quality/RoB assessments, and some of them cited tools that are not meant for assessing quality/RoB. Authors who use quality/RoB to explore the robustness of their results in meta-analyses use highly heterogeneous quality/RoB thresholds in sensitivity analyses. Better methodological consistency for quality/RoB sensitivity analyses is needed.

BackgroundThe aim of this study was to analyze whether Cochrane plain language summaries (PLSs) adhere to the Standards for the reporting of Plain Language Summaries in new Cochrane Intervention Reviews (PLEACS).MethodsA systematic analysis of adherence to the measurable PLEACS items was performed for Cochrane PLSs published from March 2013 to the end of January 2015. Duplicate independent data extraction was performed. An adherence score was calculated for each PLS and for the Cochrane Review Groups (CRGs) that published them.ResultsOf the 1738 analyzed PLSs, not a single one adhered fully to the measured PLEACS items. The highest adherence was found for absence of details of the search strategy (99 % adherence), and the lowest adherence for an item mandating to address quality according to the GRADE system (0.7 % adherence). Overall adherence percentage of PLSs reporting reviews with included studies was 57 %. Different CRGs had a wide range of adherence scores.ConclusionsCochrane plain language summaries are highly heterogeneous with a low adherence to the PLEACS standards. Therefore, there is much room for improving the content and consistency of the PLS. A standardization of PLSs is necessary to ensure delivery of proper and consistent information for consumers.Electronic supplementary materialThe online version of this article (doi:10.1186/s12874-016-0162-y) contains supplementary material, which is available to authorized users.

Background: The research community reacted rapidly to the emergence of COVID-19. We aimed to assess characteristics of journal articles, preprint articles, and registered trial protocols about COVID-19 and its causal agent SARS-CoV-2. Methods: We analyzed characteristics of journal articles with original data indexed by March 19, 2020, in World Health Organization (WHO) COVID-19 collection, articles published on preprint servers medRxiv and bioRxiv by April 3, 2010. Additionally, we assessed characteristics of clinical trials indexed in the WHO International Clinical Trials Registry Platform (WHO ICTRP) by April 7, 2020. Results: Among the first 2118 articles on COVID-19 published in scholarly journals, 533 (25%) contained original data. The majority was published by authors from China (75%) and funded by Chinese sponsors (75%); a quarter was published in the Chinese language. Among 312 articles that self-reported study design, the most frequent were retrospective studies (N=88; 28%) and case reports (N=86; 28%), analyzing patients’ characteristics (38%). Median Journal Impact Factor of journals where articles were published was 5.099.Among 1088 analyzed preprint articles, the majority came from authors affiliated in China (51%) and were funded by sources in China (46%). Less than half reported study design; the majority were modeling studies (62%), and analyzed transmission/risk/prevalence (43%).Of the 927 analyzed registered trials, the majority were interventional (58%). Half were already recruiting participants. The location for the conduct of the trial in the majority was China (N=522; 63%). The median number of planned participants was 140 (range: 1 to 15,000,000). Registered intervention trials used highly heterogeneous primary outcomes and tested highly heterogeneous interventions; the most frequently studied interventions were hydroxychloroquine (N=39; 7.2%) and chloroquine (N=16; 3%).Conclusions: Early articles on COVID-19 were predominantly retrospective case reports and modeling studies. The diversity of outcomes used in intervention trial protocols indicates the urgent need for defining a core outcome set for COVID-19 research. Chinese scholars had a head start in reporting about the new disease, but publishing articles in Chinese may limit their global reach. Mapping publications with original data can help finding gaps that will help us respond better to the new public health emergency.