Sarah Chapman highlights Cochrane Reviews are systematic reviews. In systematic reviews we search for and summarize studies that answer a specific research question (e.g. is paracetamol effective and safe for treating back pain?). The studies are identified, assessed, and summarized by using a systematic and predefined approach. They inform recommendations for healthcare and research. on COVID-19 and other health effects of the pandemic, with links to reviews, blogs and other Cochrane resources.
While we’ve all been adapting to huge and sudden changes in our lives and healthcare workers have been meeting unprecedented challenges, scientists have scrambled to produce research evidence relevant to the pandemic. Cochrane is responding by producing rapid reviews of this new evidence on priority topics, and these are updated as new evidence emerges. They show that much of the research that has been done so far leaves us with more unanswered questions than answers, but we must hope that this changes as new studies are available to add to the reviews.
Here’s a round-up of some of the Cochrane evidence so far.
Signs and symptoms of COVID-19
We’re hearing a lot about temperature checks, which in many places are being used determine whether someone may enter a care home, hairdressers or other building. But what’s the evidence? We’ve blogged about a Cochrane Review, published in July 2020, on the accuracy of any signs and symptoms, either alone or in combination, for diagnosing COVID‐19.
You can read the blog: “Signs and symptoms of COVID-19: new Cochrane evidence“. There is also a podcast and a Cochrane Clinical Answer.
Antibody tests for COVID-19
Antibody tests have the potential to identify people who have had COVID-19. A Cochrane Review ‘Antibody tests for identification of current and past infection with SARS-CoV-2′ was published in June 2020 and we have blogged about it: “Antibody tests for COVID-19: new evidence on test accuracy and some considerations“.
Rapid tests for COVID-19, done during a health care visit
Tests to detect COVID-19 that can give a result ‘while you wait’ (within a couple of hours) could be really useful, helping people isolate quickly to reduce the spread of infection. A Cochrane Review on Rapid, point‐of‐care antigen and molecular‐based tests for diagnosis of SARS‐CoV‐2 infection was published in August 2020. The review authors anticipate that they will have an update of the review this autumn and lead author Jacqueline Dinnes is going to blog about the updated review here.
Screening for COVID-19
Screening people who have mild or no symptoms but have COVID-19, to find out if someone’s infected, is another strategy that has potential to help reduce the spread of infection, as those who are found to have the virus could then isolate, for example. A Cochrane A rapid review is a simplified systematic review that can be done in a few weeks to produce timely evidence for decision-making. on universal screening for SARS‐CoV‐2 infection was published in September 2020. The evidence base is currently very limited and highlights uncertainty about the The ability of an intervention (for example a drug, surgery, or exercise) to produce a desired effect, such as reduce symptoms. of screening for COVID-19. The review finds that:
“One‐time screening in apparently healthy people is likely to miss people who are infected. We are unsure whether combined screenings, repeated symptom assessment, or rapid laboratory tests are useful.
As more people become infected, screening will identify more cases. However, because screening can miss people who are infected, public health measures such as face coverings, physical distancing, and quarantine for those who are apparently healthy, continue to be very important.”
Here is a video summary.
Thoracic imaging tests for COVID-19
A Cochrane Review was published in September 2020 on thoracic imaging tests for the diagnosis of COVID-19. This brings together evidence on the diagnostic accuracy of chest (thoracic) imaging (computed tomography (CT), X‐ray and ultrasound) in people with suspected or confirmed COVID‐19. This is one of a suite of Cochrane ‘living systematic reviews’ summarising evidence on the accuracy of different imaging tests and diagnostic features in people regardless of their symptoms, grouped according to the research questions and settings.
The review includes 84 studies, 71 of those recruiting only people with confirmed COVID-19 and the rest involving people with suspected COVID-19. The evidence available so far leaves much uncertainty. The review finds that chest CT and chest X‐ray may be good tests for confirming COVID‐19 diagnosis in people who have been diagnosed with COVID‐19 infection using another test, but that CT scans may be less accurate in confirming or ruling out infection in people with only suspected COVID‐19.
Quarantine for controlling COVID-19
A Cochrane rapid review on quarantine alone or in combination with other public health measures to control COVID-19 was published in April 2020 and updated in September 2020. It is the focus of this blog: “Quarantine for controlling COVID-19 (coronavirus). New Cochrane evidence.”
Watch a video of the lead author summarising the review’s findings. You might also be interested in this blog ““Stay at home” rules: what makes people more likely to stick to quarantine?“, which looks at two non-Cochrane rapid reviews from researchers at King’s College London.
Contact tracing aims to reduce transmission of infection by identifying people who have been in contact with someone who has it, so that they can isolate. A Cochrane rapid review published in August 2020 looked at evidence on digital contact tracing technologies in epidemics.
The review highlights an evidence gap, the authors concluding that “the effectiveness of digital solutions is largely unproven as there are very few published Data is the information collected through research. in real‐world outbreak settings.”
Personal Protective Equipment (PPE) for healthcare workers
Two Cochrane Reviews are systematic reviews. In systematic reviews we search for and summarize studies that answer a specific research question (e.g. is paracetamol effective and safe for treating back pain?). The studies are identified, assessed, and summarized by using a systematic and predefined approach. They inform recommendations for healthcare and research. contribute to the evidence base on PPE for healthcare workers and we have a blog about these: “Personal protective equipment (PPE) for healthcare workers: new Cochrane evidence“. They look at Personal protective equipment for preventing highly infectious diseases due to exposure to contaminated body fluids in healthcare staff (May 2020) and Barriers and facilitators to healthcare workers’ adherence with infection prevention and control (IPC) guidelines for respiratory infectious diseases: a rapid qualitative evidence synthesis (April 2020).
For the review on PPE there is a Cochrane Clinical Answer. For the review on barriers and facilitators there is podcast and a Cochrane Clinical Answer. Evidence Synthesis Ireland and Cochrane Ireland have also created an infographic summarising key messages.
Antimicrobial mouthrinses and nasal sprays to protect healthcare workers and patients at risk of COVID-19
Antimicrobial mouthrinses and nasal sprays have the potential to help people with COVID-19 fight infection and prevent them infecting healthcare workers who care for them. They might also offer some protection to healthcare workers, especially if they use them before doing aerosol-generating procedures, such as drilling teeth.
Three new Cochrane Reviews were published in September 2020 looking at different aspects of this. There is a helpful summary of all three in this Cochrane Oral Health Editorial base blog Antimicrobial mouthrinses and nasal sprays to protect healthcare workers and patients at risk of COVID-19, which also has links to each of the reviews. No completed studies were found for any of the reviews, so this is currently an evidence gap, but there are ongoing studies for two of these three reviews and all will be updated.
A Cochrane rapid review, published in September 2020, has looked at travel-related control measures to contain the COVID-19 pandemic. Not surprisingly, it highlights uncertainty about their effectiveness and a lack of reliable and ‘real-life’ evidence, but the authors will update the review soon and hope there may be better evidence to include. You can read about the review in this blog “Travel-related measures for controlling the spread of COVID-19: New Cochrane evidence“.
Convalescent plasma – a possible treatment for COVID-19?
Many Clinical trials are research studies involving people who use healthcare services. They often compare a new or different treatment with the best treatment currently available. This is to test whether the new or different treatment is safe, effective and any better than what is currently used. No matter how promising a new treatment may appear during tests in a laboratory, it must go through clinical trials before its benefits and risks can really be known. are being done to investigate the potential benefits or harms of using plasma from people who have recovered from COVID-19 to treat people who are currently ill with it. This blog: “Convalescent plasma to treat people with COVID-19: the evidence so far” looks at a Cochrane rapid review on convalescent plasma to treat people with COVID-19, updated for the second time in October 2020 and highlights continued uncertainty about the potential effectiveness and Refers to serious adverse effects, such as those that threaten life, require or prolong hospitalization, result in permanent disability, or cause birth defects. of this Something done with the aim of improving health or relieving suffering. For example, medicines, surgery, psychological and physical therapies, diet and exercise changes..
Oxygen therapy for adults in intensive care with acute respiratory distress syndrome
A Cochrane rapid review on oxygen targets in the intensive care unit during mechanical ventilation for acute respiratory distress syndrome has brought together evidence on this topic. The review authors explain the context:
“A health condition (or episodes of a health condition) that comes on quickly and is short-lived. respiratory distress syndrome (ARDS) is a very severe breathing problem with a high death The speed or frequency of occurrence of an event, usually expressed with respect to time. For instance, a mortality rate might be the number of deaths per year, per 100,000 people. (chance of dying). It has many potential causes, including viral infections such as COVID‐19, and there are no specific treatments for it except for giving patients oxygen via a ventilator (artificial breathing machine) on an intensive care unit, often for long periods of time. However, large amounts of oxygen (either a high concentration of oxygen or oxygen administered for a long period of time) are associated with increased harm due to other illnesses (e.g. heart attack or stroke).”
Here’s what they found:
Prophylactic anticoagulants for people hospitalised with COVID-19
COVID‐19 may predispose people to getting blood clots in the arteries, veins and lungs. Venous and arterial thromboembolic complications affect 16% of people hospitalised with COVID‐19 and 31% to 49% of people with COVID‐19 in intensive care units, with 90% of such cases being venous thromboembolism. A Cochrane Review, Prophylactic anticoagulants for people hospitalised with COVID‐19, has looked for evidence on the effects of using blood thinning drugs to prevent this in people hospitalised with COVID-19.
As yet, there are no published Randomization is the process of randomly dividing into groups the people taking part in a trial. One group (the intervention group) will be given the intervention being tested (for example a drug, surgery, or exercise) and compared with a group which does not receive the intervention (the control group). trials and the authors conclude that there is insufficient evidence to determine the risks and benefits of prophylactic anticoagulants in this The group of people being studied. Populations may be defined by any characteristics e.g. where they live, age group, certain diseases.. However, they found 22 studies in progress which plan to evaluate 15,000 people, which will be considered for future updates of the review.
Interventions for heavy menstrual bleeding
Pandemics disrupt healthcare provision. With this in mind, a Cochrane Overviews of reviews (Overviews) are intended to summarize multiple Cochrane Reviews addressing the effects of two or more potential interventions (for example a drug, surgery, or exercise) for a single condition or health problem. (July 2020) has been done on interventions commonly available during pandemics for heavy menstrual bleeding. You can see summaries of the review here, including an infographic to help women make choices about treatment. There is also a podcast about this review and two Cochrane Clinical Answers.
Routine vaccinations during the pandemic
The World Health Organization (WHO) has emphasized the importance of keeping up with routine vaccinations during the pandemic, advice endorsed by Public Health England. A Cochrane Review on vaccines for measles, mumps, rubella and varicella in children (published April 2020) was discussed in this blog: “MMR vaccines: do they work and are they safe?“.
There are two Cochrane Clinical Answers related to this review.
Social isolation and loneliness in older people
With restrictions imposed during the pandemic increasing isolation for many, a Cochrane rapid review (May 2020) looked for evidence on video calls for reducing social isolation and loneliness in older people. We discuss the review in this blog: “Loneliness in older people: could video calls help?”
Quitting smoking to improve respiratory health
Given the current threat from COVID-19, an acute respiratory infection, there has never been a better time to stop smoking, and the World Health Organization is urging people to do so. We have looked at evidence from a new Cochrane Special Collection, COVID-19: Effective options for quitting smoking during the pandemic, in this blog: “Smoking and coronavirus (COVID-19): time to quit.”
The Special Collection on quitting smoking during the pandemic is one of seven Cochrane Special Collections on COVID-19. Developed with experts from our global Cochrane network, they are based on World Health Organization interim guidance, and continuously updated.
Like the reviews themselves, we update our blogs to reflect the latest evidence. There are new reviews coming up, as well as updates of existing reviews, so check back for additions to this blog.
Keeping up to date
As well as coming back to this blog, you can find Cochrane resources and news on COVID-19 here and this will also be continually updated.
What COVID-19 evidence have you found useful and what would you like to see in the future? Please complete this Cochrane survey to let us know. Thank you.
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Editor’s note: This blog was last updated on 12 October 2020.