A Systematic Map of Non-Clinical Evidence Syntheses Published Globally on COVID-19.

STUDY OBJECTIVE: Evidence syntheses perform rigorous investigations of the primary literature and they have played a vital role in generating evidence-based recommendations for governments worldwide during the Covid-19 pandemic. However, there has not yet been an attempt to organize them by topic and other characteristics. This study performed a systematic mapping exercise of non-clinical evidence syntheses pertaining to Covid-19. METHODS: This study conducted a systematic search on December 5, 2020 across 10 databases and servers: CINAHL (EBSCO Information Services, Ipswich, Massachusetts, United States), Embase (Elsevier, Aalborg, Denmark), Global Health (EBSCO Information Services, Ipswich, Massachusetts, United States), Healthstar (NICHSR and AHA, Bethesda, United States), MEDLINE (NLM, Bethesda, United States), PsychINFO (APA, Washington, DC, United States), Web of Science (Clarivate Analytics, London, UK), Research Square (Research Square, Durham, North Carolina), MEDRxiv (Cold Spring Harbor Laboratory, New York, United States), and PROSPERO (NIHR, York, United Kingdom). Only full evidence syntheses published in a peer-reviewed journal or preprint server were included. RESULTS: This study classified all evidence syntheses in the following topics: health service delivery (n = 280), prevention and behavior (n = 201), mental health (n = 140), social epidemiology (n = 31), economy (n = 22), and environment (n = 19). This study provides a comprehensive resource of all evidence syntheses categorized according to topic. CONCLUSIONS: This study proposes the following research priorities: governance, the impact of Covid-19 on different populations, the effectiveness of prevention and control methods across contexts, mental health, and vaccine hesitancy.

Viscosupplementation for knee osteoarthritis: systematic review and meta-analysis.

OBJECTIVE: To evaluate the effectiveness and safety of viscosupplementation for pain and function in patients with knee osteoarthritis. DESIGN: Systematic review and meta-analysis of randomised trials. DATA SOURCES: Searches were conducted of Medline, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL) databases from inception to 11 September 2021. Unpublished trials were identified from the grey literature and trial registries. ELIGIBILITY CRITERIA FOR STUDY SELECTION: Randomised trials comparing viscosupplementation with placebo or no intervention for knee osteoarthritis treatment. MAIN OUTCOME MEASURES: The prespecified primary outcome was pain intensity. Secondary outcomes were function and serious adverse events. Pain and function were analysed as standardised mean differences (SMDs). The prespecified minimal clinically important between group difference was -0.37 SMD. Serious adverse events were analysed as relative risks. METHODS: Two reviewers independently extracted relevant data and assessed the risk of bias of trials using the Cochrane risk of bias tool. The predefined main analysis was based only on large, placebo controlled trials with ≥100 participants per group. Summary results were obtained through a random effects meta-analysis model. Cumulative meta-analysis and trial sequential analysis under a random effects model were also performed. RESULTS: 169 trials provided data on 21 163 randomised participants. Evidence of small study effects and publication biases was observed for pain and function (Egger's tests with P<0.001 and asymmetric funnel plots). Twenty four large, placebo controlled trials (8997 randomised participants) included in the main analysis of pain indicated that viscosupplementation was associated with a small reduction in pain intensity compared with placebo (SMD -0.08, 95% confidence interval -0.15 to -0.02), with the lower bound of the 95% confidence interval excluding the minimal clinically important between group difference. This effect corresponds to a difference in pain scores of -2.0 mm (95% confidence interval -3.8 to -0.5 mm) on a 100 mm visual analogue scale. Trial sequential analysis for pain indicated that since 2009 there has been conclusive evidence of clinical equivalence between viscosupplementation and placebo. Similar conclusions were obtained for function. Based on 15 large, placebo controlled trials on 6462 randomised participants, viscosupplementation was associated with a statistically significant higher risk of serious adverse events than placebo (relative risk 1.49, 95% confidence interval 1.12 to 1.98). CONCLUSION: Strong conclusive evidence indicates that viscosupplementation leads to a small reduction in knee osteoarthritis pain compared with placebo, but the difference is less than the minimal clinically important between group difference. Strong conclusive evidence indicates that viscosupplementation is also associated with an increased risk of serious adverse events compared with placebo. The findings do not support broad use of viscosupplementation for the treatment of knee osteoarthritis. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42021236894.

Drug treatments for covid-19: living systematic review and network meta-analysis

OBJECTIVE: To compare the effects of treatments for coronavirus disease 2019 (covid-19). DESIGN: Living systematic review and network meta-analysis. DATA SOURCES: WHO covid-19 database, a comprehensive multilingual source of global covid-19 literature, up to 3 December 2021 and six additional Chinese databases up to 20 February 2021. Studies identified as of 1 December 2021 were included in the analysis. STUDY SELECTION: Randomised clinical trials in which people with suspected, probable, or confirmed covid-19 were randomised to drug treatment or to standard care or placebo. Pairs of reviewers independently screened potentially eligible articles. METHODS: After duplicate data abstraction, a bayesian network meta-analysis was conducted. Risk of bias of the included studies was assessed using a modification of the Cochrane risk of bias 2.0 tool, and the certainty of the evidence using the grading of recommendations assessment, development, and evaluation (GRADE) approach. For each outcome, interventions were classified in groups from the most to the least beneficial or harmful following GRADE guidance. RESULTS: 463 trials enrolling 166 581 patients were included; 267 (57.7%) trials and 89 814 (53.9%) patients are new from the previous iteration; 265 (57.2%) trials evaluating treatments with at least 100 patients or 20 events met the threshold for inclusion in the analyses. Compared with standard care, three drugs reduced mortality in patients with mostly severe disease with at least moderate certainty: systemic corticosteroids (risk difference 23 fewer per 1000 patients, 95% credible interval 40 fewer to 7 fewer, moderate certainty), interleukin-6 receptor antagonists when given with corticosteroids (23 fewer per 1000, 36 fewer to 7 fewer, moderate certainty), and Janus kinase inhibitors (44 fewer per 1000, 64 fewer to 20 fewer, high certainty). Compared with standard care, two drugs probably reduce hospital admission in patients with non-severe disease: nirmatrelvir/ritonavir (36 fewer per 1000, 41 fewer to 26 fewer, moderate certainty) and molnupiravir (19 fewer per 1000, 29 fewer to 5 fewer, moderate certainty). Remdesivir may reduce hospital admission (29 fewer per 1000, 40 fewer to 6 fewer, low certainty). Only molnupiravir had at least moderate quality evidence of a reduction in time to symptom resolution (3.3 days fewer, 4.8 fewer to 1.6 fewer, moderate certainty); several others showed a possible benefit. Several drugs may increase the risk of adverse effects leading to drug discontinuation; hydroxychloroquine probably increases the risk of mechanical ventilation (moderate certainty). CONCLUSION: Corticosteroids, interleukin-6 receptor antagonists, and Janus kinase inhibitors probably reduce mortality and confer other important benefits in patients with severe covid-19. Molnupiravir and nirmatrelvir/ritonavir probably reduce admission to hospital in patients with non-severe covid-19. SYSTEMATIC REVIEW REGISTRATION: This review was not registered. The protocol is publicly available in the supplementary material. READERS' NOTE: This article is a living systematic review that will be updated to reflect emerging evidence. Updates may occur for up to two years from the date of original publication. This is the fifth version of the original article published on 30 July 2020 (BMJ 2020;370:m2980), and previous versions can be found as data supplements. When citing this paper please consider adding the version number and date of access for clarity.