Cochrane Belgium, together with TranspariMED, Test Aankoop and Kom op tegen Kanker, recently released a report detailing the status of clinical trial transparency in Belgium.
The report used data collected on the EU Trials Tracker, which monitors the status of clinical trials recorded in the EU Clinical Trials Register. According to EU legislation, clinical trial sponsors must post summary results to the register within one year of a study ending (or six months for paediatric trials).
Several clinical trial sponsors in Belgium with overdue results were reminded last year to update the registry. While some then took significant steps to upload missing data, others have made little progress.
22% of verifiably due trials were found to have not yet posted results on the registry. However, it is likely that far more trials are still missing results, since only 292 of 1,098 registered trials are marked as complete – including several which started over 10 years ago and are likely not still ongoing. Results from trials sponsored by universities and hospitals were also found to be missing more often than trials with commercial sponsors.
The paper also calls upon the Belgian medicines regulator, AFMPS, to ensure that information on trials is kept up to date and recommends that research funders in Belgium monitor trial reporting.
A follow-up report is planned in six months to track further progress on this issue.
Cochrane supports clinical trial transparency. We rely on the availability of results from clinical trials to produce high quality and relevant systematic reviews. When trial results are not published, it is not possible to make truly evidence-informed decisions about healthcare, and people can be put at risk of harm.
Interested in learning more on this issue? Free webinar on 16 June
Cochrane Sweden and Lund University are hosting a webinar on clinical trial registration and reporting on 16 June at 13:30-15:30 (CEST).
The session will be an opportunity to learn more about the ethical and legal requirements around trial transparency.
This Evidently Cochrane blog (originally posted here) is for all those involved in clinical trials. Katie Gillies and Derek Stewart, from the Trials Methodology Research Partnership and the Health Research Board Trials Methodology Research Network, highlight the need for focussed research on trial retention to help fill the evidence gaps identified in a national research agenda on retention to clinical trials developed and prioritised by all relevant stakeholders.
What do we know about the best ways to keep people involved in clinical trials? Frankly, not a lot.
Clinical trials can provide evidence about which treatments work. Clinical trials are research studies that involve people and compare different groups of people receiving different treatments and look at which treatments improve outcomes (like pain) the most. During the design of a trial, calculations are made about how many people need to join the trial and complete all of the data collection requirements (which might be, for example, a questionnaire or a clinic appointment). These calculations allow the researchers to be confident in the results at the end of the trial.
If there are problems with keeping people involved in a clinical trial this can often result in a delay in completing the trial or problems in using the results to make informed decisions about clinical care. Identifying ways to keep people involved in trials, i.e. they provide all of the data or measurements that the trial needs, has been identified as one of the top priorities for research into the design and delivery of clinical trials.What is already known about retention to clinical trials?
So, we don’t know a lot about how to keep people in trials but we do know a little. What we do know focuses on how to get trial participants to return postal questionnaires. Evidence from a recent Cochrane Review Strategies to improve retention in randomised trials (March 2021) suggests that some approaches may improve return rates of postal questionnaires. However, we we are not able to say with confidence that any of the results we found is a true effect and not caused by other factors, such as flaws with the design of the studies. As such, the effect of ways to encourage people to stay involved in trials is still not clear and more research is needed to see if these retention methods really do work. Of the 70 relevant articles we identified only two of those investigated how best to encourage people to attend clinical visits as part of the trial follow up. Of the studies included in the Cochrane Review on strategies to improve retention to RCTs only a handful included patients as partners in their design – this needs to change. We should be involving trial participants in decision-making about how best to improve retention.Where should research teams focus efforts?
The Cochrane review did, however, identify key strategies that research teams should focus on. The first set of priorities requires replication of evaluations of existing interventions using high quality evaluations of to provide evidence as to whether such strategies are effective or not. These four strategies all focus on are:
- Monetary incentives: specifically, does giving a £5 gift voucher at same time as sending the questionnaire improve response to postal questionnaires.
- Return postage: several return postage strategies have been evaluated to improve response of postal questionnaire e.g. reply paid compared to second class stamps, business post etc. Ensuring participants are not out of pocket is key, but which strategy to evaluate could be decided by the patient partners involved in the trial.
- Pens: A number of studies have evaluated the inclusion of a pen with a postal questionnaire to improve response. It looks promising but further studies, specifically in trials that include younger populations with participants who are men are required.
- Electronic reminders: emails or text messages reminding people (so sent in advance of the questionnaire) may also have an effect on postal questionnaire return. High quality replications are required.
These evaluations will help to provide evidence for trial teams as to what works to improve responses to postal questionnaires. They will begin to answer some of the questions identified as the top priorities for trials methodology retention research from a priority setting partnership (PSP) designed and delivered in association with the James Lind Alliance (JLA), the PRioRiTY II project. These prioritisation exercises help researchers and funders to focus on what matters most to all of those involved and ultimately contributes to global efforts to minimise waste in research by focussing activities. Future efforts to improve retention in trials should aim to target at least one of these stakeholder agreed priorities.
The past year has shone a bright light on the importance of clinical trials to provide evidence to inform health care decision making, But trials are only valuable if they recruit and retain enough people so that meaningful conclusions can be drawn from the results. Focussing efforts on keeping people in trials is effort well spent and will result in more valid and reliable result son which to base decisions for all.
- Join in the conversation on Twitter with @GilliesKatie @DerekCStewart @CochraneUK
- Leave a comment on the Evidently Cochrane blog post
- Read the Cochrane Review 'Strategies to improve retention in randomised trials'
- References [PDF]
Lifeology’s tagline is ‘The place where science and art converge’. They offer a platform that brings together scientists, artists, and storytellers to help people better understand and engage with science and health information and research. One of the main ways they meet their objectives is through beautifully illustrated, science-backed, bite-sized ‘flashcard’ courses about science and health-related topics aimed at the general public and students. We spoke to Paige Jarreau, VP of Science Communication at LifeOmic and co-founder of Lifeology more about their work.
Can you tell us a bit more about yourself?
My name is Paige Jarreau and I am VP of Science Communication at LifeOmic, a health software company. I am the co-founder of Lifeology (a LifeOmic product) along with Doryan Algarra, the VP of Design at LifeOmic.
I am a scientist turned storyteller and science communication scholar. When I was a child, the first thing I ever wanted to be when I grew up was a poet (or a science fiction writer!). As I got older I settled on a more “practical” career path as a doctor or a biomedical engineer - I imagined creating artificial organs and implants. But many years later I was enrolled in a PhD program in biomedical engineering when I realized that writing and creative expression needed to become my priority again, for my own mental health and fulfillment. From there, I never looked back. I started science blogging and ultimately got my PhD in Mass Communication studying science communication in new media environments.
Over the past decade, my interest in creative science communication has slowly morphed from primarily written to visual methods and formats. For example, I became interested in how scientists’ “selfies” on Instagram could help people see them as more human and trustworthy! I became interested in how art could make science more relatable to people. Meeting and collaborating with Doryan at LifeOmic was a turning point in my change in perspective of what good science communication looks like. We founded Lifeology on the idea that art is a critical, foundational aspect of engaging and accessible science communication - but that scientists struggle to create this art on their own.
How did Lifeology get started?
Lifeology, a platform that combines science and art, was the brainchild of my friend and coworker Doryan Algarra, VP of Design at LifeOmic. Over the course of his time at LifeOmic, Doryan has worked on the design of all kinds of products that facilitate precision medicine and wellness. In this work, he has realized that science and health information is often presented in overly complex and technical ways, or in outdated ways such as doctors’ office brochures that are not accessible and inclusive, much less interesting and beautiful to look at. Before developing the idea of Lifeology, Doryan had also been inspired by a book he was reading on epigenetics, of all things. Doryan generally felt that the book was complex and hard to follow. But he remembers one particular chapter to this day that helped the concept of epigenetics finally “click” for him. The chapter started with a question and then told a story about how some bees become queens and the rest become workers - based on different diets that affect the expression of their DNA! This got Doryan thinking about how even small storytelling devices and metaphors could help him understand and remember science that he thought was too difficult and niche for him to understand, let alone enjoy! As a designer, he quickly began imagining how these metaphors, and the “invisible” factors of epigenetics, could be made visual for even more impact.
Fast forward a few months, and Doryan had designed a prototype of what we know as Lifeology “flashcard” courses today. By giving art and science the same “real estate” on each “flashard” and making these courses easy to access and fun to interactively navigate on a phone, he hoped to make science and health information less intimidating and more inviting. He hoped to make science and health information more accessible to all people, including people who might be distrustful of or put off by science.
When Doryan showed me his Lifeology prototype, I was in awe. Like Doryan, I saw in these flashcard courses an innovative and fun way of delivering science information to broad audiences. But in talking through how courses would be created, we also began to see an opportunity to bring scientists and artists together to create the content as a team. Working together (a designer with a science communicator!) we became convinced that sci-art collaboration had to be a core feature of Lifeology courses. Today, we and the rest of the Lifeology team are baking collaboration tools and community into our platform to allow scientists, storytellers and artists to easily work together in the creation of Lifeology courses for broader audiences. We do this through cloud-based software collaboration tools but also processes and educational materials that help scientists and artists successfully collaborate to create better science communication.
What does Lifeology do?
Lifeology is a platform and communication tool that engages broader audiences in science, health and research in a fun, accessible way. We do this by bringing together science and art in our bite-sized digital “flashcard” courses. We designed these courses and their creation process to engage populations underserved by many science communication efforts - people with low literacy for example, and populations who tend to mistrust healthcare, science and government. Self-paced learning, empathetic storytelling and inclusive visuals are some of our key elements.
But we also believe that science communication in any format, including our flashcard courses, is far better when it is the product of collaboration between scientists and professional creatives like storytellers and artists. That is why we embedded within the Lifeology platform a growing community of storytellers, translators and artists from all over the world who want to collaborate with scientists. We have over 800 members in this community today! Our Lifeology platform guides scientists and other experts through successful collaborations with storytellers and artists as they create Lifeology courses together.
Teaching people the skillset to communicate science seems important to Lifeology. Can you tell us more?
Absolutely. While there are many tools out there that try to make it easier for scientists to create visual content to communicate their work, no tool can replace the need for collaboration and empathetic storytelling. To help scientists be successful in creating engaging, accessible and inclusive Lifeology courses (or other other science communication products!), we try to teach them key science communication skills, from knowing their audience, to how to tell a story, to how to be inclusive, to how to work with artists. One way we are doing this is through our Lifeology University SciComm Program, a free series of Lifeology courses and activities that help scientists become better communicators!
What advice do you have for researchers who want to communicate their review findings out?
Our most important piece of advice is to collaborate! Collaborate with members of the communities you are trying to reach with communication of your findings. Get to know your audience and involve them in the creation of culturally relevant content. Collaborate with community leaders. Collaborate with storytellers and artists who excel at creating content that connects with people on an emotional as well as a cognitive level.
The World Health Organization has said that in addition to dealing with a global COVID-19 Pandemic we are also dealing with a Pandemic with all the misinformation being spread. What do you think about this?
Misinformation around COVID-19 has certainly become its own pandemic or “infodemic.” The uncertainty, anxiety and fear that have surrounded the spread of COVID-19 have only accelerated this spread of misinformation. Uncertainty, anxiety and fear drove people to seek their own answers to questions that science didn’t have clear answers to yet.
In my mind, the only way to deal with this, from a science communication perspective, is through transparency, empathy and storytelling that is driven by data but also by local knowledge systems. It takes two-way communication and not making people feel bad for falling for misinformation, while also clearly and accessible presenting what we know now and solutions that people can actually put into practice locally.
There is also plenty that each of us can do to double-check what we read online and to prevent spreading misinformation.
Plans are in the works for some future collaborations between Cochrane and Lifeology. What are your thoughts on this?
We are so excited to collaborate! We hope to produce beautifully illustrated and accessible educational content around the topic of infodemics and what we can all do to prevent the appearance and spread of misinformation.
If you would like to learn more about Lifeology:
If you would like to learn more about knowledge translation and disseminating evidence at Cochrane:
Featured review: Reducing nausea and vomiting in women having a caesarean birth with regional anaesthesia
Featured review: What are the benefits and risks of a single injection of ketorolac (an anti‐inflammation medicine) for relieving short‐term pain after surgery in adults
Specifications: Part time or Fulltime considered (Fixed term/ Secondment/ Consultancy role)
Salary: circa £45,000 per annum full time equivalent
Application Closing Date: 29 May 2021
Assist with the provision and delivery of commissioned systematic reviews and review tasks for Cochrane Response, Cochrane’s evidence consultancy unit.
Cochrane Response provides a broad range of literature review and evidence synthesis services to international policy makers and guideline developers to support evidence informed healthcare decision making. We work closely with Cochrane networks to increase Cochrane’s capacity to respond to requests for commissioned evidence reviews and tailored evidence services.
In line with Cochrane’s Goal 4 of the Strategy to 2020: to support building an effective and sustainable organisation by ensuring the success of Cochrane Response as a business unit that produces relevant information to guide healthcare decisions and responds to the needs of our stakeholders.
As a Systematic Reviewer, you will assist with the provision and delivery of commissioned systematic reviews and review tasks for Cochrane Response, Cochrane’s evidence consultancy unit.
Cochrane is a global, independent network of health practitioners, researchers, patient advocates and others, responding to the challenge of making vast amounts of research evidence useful for informing decisions about health. We do this by synthesizing research findings to produce the best available evidence on what can work, what might harm and where more research is needed. Our work is recognised as the international gold standard for high quality, trusted information. An understanding of Cochrane’s work and health research more generally is an advantage, but not essential.
The majority of Cochrane Central Executive staff are located in London, UK, however flexible location or a part-time appointment are possible for the right candidate.
How to apply
- For further information on the role and how to apply, please click here
- The deadline to receive your application is by 29 May 2021
- The supporting statement should indicate why you are applying for the post, and how far you meet the requirements, using specific examples.
- Note that we will assess applications as they are received, and therefore may fill the post before the deadline.
Pressure ulcers, also known as pressure sores or bed sores, are wounds to the skin and underlying tissue caused by prolonged pressure or rubbing. People who have mobility problems or who lie in bed for long periods are at risk of developing pressure ulcers.
Cochrane Wounds has recently published a suite of reviews on this topic, lead author Chunhu Shi tells us about these reviews.
How did this suite of reviews come about?
The relative effectiveness of different types of beds and mattresses (support surfaces) for preventing pressure ulcers prevention came out as a “top uncertainty” in a priory setting exercise involving patients, carers and health care professionals. We were awarded funding from the National Institute for Health Research to review the research on this topic.
In the beginning, we thought we would update an existing, large Cochrane review, Support surfaces for pressure ulcer prevention. This review was one of our most downloaded, with 11,835 downloads in 2019. However, we were concerned that the existing review was too large and difficult for readers to navigate. Furthermore, its size and complexity made it difficult to update. We therefore decided to split the review into four new review titles plus an overview that would include a network meta-analysis, to pull all comparisons together.
Before embarking on the splitting and restructure of the review, we consulted users of our reviews via an online survey. In the survey we explained the rationale for splitting the review and outlined our suggested new review titles and comparisons. Our stakeholders were positive about the plan so we proceeded to split the original review into four new reviews plus an overview.
Whilst addressing the evidence for pressure ulcer prevention we decided to also update our review of the effects of support surfaces for the treatment of pressure ulcers and include these data in the overview. In doing this we hoped to create a “one-stop-shop” on the evidence for support surfaces.
What led to these topics being picked?
Support surfaces such as beds and mattresses are widely-used and the focus of recommendations in pressure injury guidelines globally. However, decision-makers are faced with a confusing array of devices to choose from and consequent uncertainty. In splitting the review, we aimed to ensure each new review was as clinically comprehensive and relevant as possible. We used the support surface classification of the (US) National Pressure Injury Advisory Panel to structure our reviews, ensuring international, as well as national relevance.
Tell us about the prioritisation exercise
Full details about the priority setting exercise can be found here. Briefly, The James Lind Alliance approach is open and participatory. Patients, carers and health care professionals worked together to identify and rank the key ‘uncertainties’ that would benefit from research (including systematic reviews). More than 450 uncertainties were submitted to the Pressure Ulcer Partnership and these were crystallised into a top 12. Support surfaces for pressure ulcer prevention was ranked at number four.
Who are the reviews particularly useful for? Does any of the evidence stand out as useful for those caring for people with pressure ulcers, or those who have ulcers themselves?
We think these Cochrane reviews plus the overview are relevant to anyone making choices about using support surfaces to prevent and treat pressure ulcers, including carers and people at risk of (or who already have) pressure ulcers.
- Visit the Wounds Group page here
- View the full reviews here:
- Beds, overlays and mattresses for treating pressure ulcers
- Alternating pressure (active) air surfaces for preventing pressure ulcers
- Alternative reactive support surfaces (non-foam and non-air-filled) for preventing pressure ulcers
- Foam surfaces for preventing pressure ulcers
- Reactive air surfaces for preventing pressure ulcers
Featured review: Internet-based cognitive and behavioural therapies for post-traumatic stress disorder (PTSD)
Why was this review important?
Post-traumatic stress disorder, or PTSD, is a common mental illness that can occur after a serious traumatic event. Symptoms include re-experiencing the trauma as nightmares, flashbacks, and distressing thoughts; avoiding reminders of the traumatic event; experiencing negative changes to thoughts and mood; and hyperarousal, which includes feeling on edge, being easily startled, feeling angry, having difficulties sleeping, and problems concentrating. PTSD can be treated effectively with talking therapies that focus on the trauma. Some of the most effective therapies are those based on cognitive behavioural therapy (CBT). Unfortunately, there are a limited number of qualified therapists who can deliver these therapies. There are also other factors that limit access to treatment, such as the need to take time off work to attend appointments, and transportation issues.
An alternative is to deliver psychological therapy on the Internet, with or without guidance from a therapist. Internet-based cognitive and behavioural therapies (I-C/BT) have received a great deal of attention and are now used routinely to treat depression and anxiety. There have been fewer studies of I-C/BT for PTSD, yet research is expanding and there is a growing evidence base for their efficacy.
We spoke to lead author; Natalie Simpson who said "We’re living through unprecedented times, and whilst we cannot yet be sure of the full impact of the COVID-19 pandemic, an increase in PTSD lived experience is expected. Literature highlights the COVID-19 pandemic as a turning point for increased e-Health, though a drive towards improving access to psychological therapies was of course evident pre-pandemic, with an increasing number of internet-based interventions in use to treat mental health conditions, including PTSD.
The findings of this review are therefore important to understand the growing evidence base of internet-based therapies for PTSD, and particularly timely given the necessities to provide ‘COVID-proof’ treatment options, and alternatives to face-to-face therapies. The efficacy of internet-based cognitive and behavioural therapies for PTSD is evident, with guided, rather than non-guided interventions, and trauma-focused, rather than non-trauma-focused interventions, found to be more effective in reducing PTSD symptoms.
Further studies are however needed and it was encouraging to find many planned and ongoing studies."
Who will be interested in this review?
- People with PTSD and their families and friends
- Professionals working in mental health services
- General practitioners
What questions did this review try to answer?
In adults with PTSD, we tried to find out if I-C/BT:
- was more effective than no therapy (wait list);
- was as effective as psychological therapies delivered by a therapist;
- was more effective than other psychological therapies delivered online; or
- was more effective than education about the condition delivered online, at reducing symptoms of PTSD, and improving quality of life; or
- was cost effective, compared to face-to-face therapy?
Which studies did the review include?
We searched for randomised controlled trials (clinical studies where people are randomly put into one of two or more treatment groups) that examined I-C/BT for adults with PTSD, published between 1970 and 5 June 2020.
We included 13 studies with 808 participants.
What did the evidence from the review tell us?
- Analyses including 10 studies found that I-C/BT was more effective than no therapy (waiting list), at reducing PTSD. However, the quality of the evidence was very low, which means we have very little confidence in this finding.
- Analyses including two studies found there was no difference between I-C/BT and another type of psychological therapy delivered online. However, the quality of the evidence was very low, which means we have very little confidence in this finding.
- One study found that face-to-face non-CBT was more effective than I-C/BT. However, baseline levels of PTSD symptoms were not controlled for and the quality of this evidence was very low, which limits our confidence in this finding.
- We found no studies using standardised or validated measures of acceptability to tell us whether people who received I-C/BT felt it was an acceptable treatment.
- We found no studies that reported the cost-effectiveness of I-C/BT.
What should happen next?
The current evidence base is growing but still small. More studies are needed to decide if I-C/BT should be used routinely for the treatment of PTSD.
In this author interview we find out more about this recently published Network Meta-analysis, New generation antidepressants for depression in children and adolescents. Authors Dr. Sarah Hetrick and Nick Meader tell us about this work.
What were you trying to find out with this Network Meta-Analysis?
We were trying to find out how well newer generation antidepressants work compared with placebo and if some are more effective than others. We wanted to know how these antidepressants affect:
- symptoms of depression;
- recovery: no longer meeting diagnostic criteria for major depressive disorder;
- response or remission: scores on a scale indicating an important reduction in depression or no longer experiencing depression;
- ability to function in daily life;
- suicide-related outcomes; and
- whether they cause any unwanted effects in children and adolescents.
What is included in this review?
The review includes randomised controlled trials that test the efficacy of newer generation antidepressants compared with placebo in children and adolescents with depression. New generation antidepressants are those that have been developed recently. They are sometimes referred to as ‘second-‘ and ‘third-generation’ antidepressants; they do not include older formulations (tricyclic antidepressants or monoamine oxidase inhibitors).
Who will be most interested in this research?
People who support young people with depression, including both family and informal supports as well as clinicians who provide therapy and those who are able to prescribe medication.
In summary, what does the evidence in this review tell us?
Most newer antidepressants probably reduce depression symptoms better than a placebo (a 'dummy' treatment that does not contain any medicine but looks identical to the medicine being tested). However, the reduction is small and may not be experienced as important by children and adolescents, their parents and caregivers, or clinicians. When different medications are compared against each other, there may be only small and unimportant differences between most of them for the reduction of symptoms.
Our findings reflect what happens on average to individuals, but some individuals may experience a greater response. It is also the case that some people may experience a small change as important. This might lead to recommendations being made for the use of antidepressants for some individuals in some circumstances. Our findings suggest that sertraline, escitalopram, duloxetine, and fluoxetine can be used if medication is being considered.
We found small and probably negligible improvements in depression symptoms for newer antidepressants compared with placebo. We found differences between newer antidepressants were also probably negligible.
The evidence, as a whole, was limited. But for the effects of newer antidepressants on suicidal behaviour, there was even greater uncertainty. Firstly, children and young people at risk of suicide were often not included in these studies. So we can't be confident how newer antidepressants effect this group. Secondly, because suicidal behaviour is quite rare, future studies need to include more people before we can make firmer conclusions.
We found that selective serotonin reuptake inhibitor (SSRI) and serotonin-norepinephrine reuptake inhibitor (SNRI) classes of newer antidepressants may increase the risk of suicidal behaviour. But the impact on suicidal behaviour of most other newer antidepressant classes and most individual newer antidepressants was unclear.
How will this impact guidance and existing guidelines?
Our findings suggest sertraline, escitalopram, duloxetine, as well as fluoxetine (which is currently the only treatment recommended for first-line prescribing) could be considered as a first option. This larger range of first line options is a new finding and has implications for existing guidelines. This is in the context of the above findings of the reduction in depression being small and our uncertainty about how this reduction will be experience (as important or not) by young people taking the medication.
Guideline recommendations vary. For example, in the UK, NICE has recommended since 2005 that if an antidepressant is prescribed for children or young people, it should be fluoxetine.
However, our systematic review suggests there may now be negligible differences between fluoxetine and a number of newer antidepressants such as sertraline, escitalopram, and duloxetine. So these new findings may have implications for guidance in the future.
But these are complex judgements. Guideline groups will ultimately have to weigh up whether this new evidence sufficiently changes the balance of benefits and risks to warrant a change in practice. Similarly, we don't yet know whether differences we have judged to be small and unimportant are perceived that way by young people prescribed these medications.
For a clinician or parent making a decision about treatment, it’s a complicated area, especially if risk of suicide is being considered. How can this help people making these decisions?
It is important that those considering medication (including young people, their parents/families, and clinicians) understand that they may only experience a small change in their depression as a result of medication. It is also important that they know that there are several medications that they could try. What is very important is that if they do decide to take one of these medications, the impact of medication on depression symptoms should be closely monitored by those prescribing the medication, especially as suicide-related thinking and behaviour may be increased in those taking these medications. Close monitoring of suicide-related behaviours is vital in those treated with new generation antidepressants.
In this recently published Cochrane review, authors explored the effects of treating acute ischaemic stroke with endovascular thrombectomy and intra-arterial interventions.
First author Melinda Roaldsen said: "This review of endovascular thrombectomy for acute ischaemic stroke strongly reinforces the efficacy and safety of endovascular interventions. Endovascular thrombectomy is a treatment modality in rapid development and continues to gain significance in acute stroke care. This review finds high evidence that endovascular thrombectomy improves functional and neurological outcomes without increasing intracerebral haemorrhage or death. The benefit was seen with and without intravenous thrombolysis and was unrelated to age, sex, and time to treatment (though most trials are within 6 hours). Benefits were greater with more severe stroke. It is important to continue working towards making endovascular thrombectomy readily available for larger parts of the population."
This review addressed whether endovascular thrombectomy (removal of a blood clot in a blood vessel using a mechanical device) or intra-arterial thrombolysis (injecting clot-dissolving drugs directly into the clot), or both, provide better outcomes than standard treatment alone in stroke caused by a blocked blood vessel.
The majority of disabling strokes are due to a blockage of a large blood vessel by a blood clot in the brain. Such strokes lead to brain tissue damage because of oxygen deprivation. An ischaemic stroke is a stroke where the restriction of blood flow causes damage and death to the surrounding tissue due to oxygen shortage. For these patients, the most intuitive means of treatment is removal of the blockage by either injecting clot-dissolving drugs directly into the clot or removal of the blood clot using a mechanical device, or both. Prompt treatment can restore blood flow before major brain damage has occurred, leading to a good recovery. However, these treatments can also cause bleeding in the brain, which can result in poorer outcomes. The authors searched for randomised controlled trials (studies in which participants are assigned to one of two or more treatment groups using a random method) of both endovascular mechanical thrombectomy and intra-arterial thrombolysis to establish whether they are safe and effective treatments for stroke caused by a blocked blood vessel.
Search date: 1 September 2020
Randomised controlled trials of endovascular thrombectomy or intra-arterial thrombolysis, or both, plus routine medical treatment compared with routine medical treatment alone in people with a definite acute ischaemic stroke.
Study funding sources
No funding sources
Review authors found 19 trials involving a total of 3793 participants. Treatment with endovascular thrombectomy can improve patients’ chance of survival with the ability to function well without increasing the risk of bleeding in the brain or death. It is still unclear what the optimal time window is within which treatment is beneficial and whether treatment is effective in the posterior (supplying the rear part of the brain) circulation. There is also a need to study whether a strategy of primary endovascular thrombectomy or intra-arterial thrombolysis, or both, is superior to a strategy where intravenous (injected into the vein) clot-dissolving treatment is provided first in a local centre followed by transfer of selected patients to hospitals able to perform mechanical thrombectomy or intra-arterial thrombolysis, or both.
Certainty of the evidence
The authors judged the available trials to be at low or unclear risk of bias, and so overall the evidence is reported to be of high certainty.
Cochrane, together with a range of other civil society organisations, has written to a group of medicines agencies in Europe asking that they take action to ensure trial transparency.
Despite an EU legislation requiring that results from clinical trials be published on the EU Clinical Trials Register within 12 months of a study ending, this information has not been shared for almost 30% of applicable trials.
The letter calls on the Heads of Medicines Agencies (HMA), a body of national regulators in Europe, to take action to address this serious issue and gives recommendations on how to improve the situation. This includes relatively simple steps like writing to the clinical trial sponsors whose results are overdue to remind them of their obligation to share a summary of their findings.
Dr Karla Soares-Weiser, Editor in Chief of The Cochrane Library and Acting CEO of Cochrane, said:
“Cochrane strongly supports efforts to ensure that data from all clinical trials are available and encourages HMA to take action on these recommendations. Without access to reliable information from all clinical trials, the evidence base on which to make judgements is incomplete – this limits the scientific community’s ability to learn from research findings and can lead to patients being harmed.”
Specifications: Full Time, 40hr/week
Location: Flexible location - ideally US-based but open to international candidates.
Application Closing Date: TBD
The Cochrane Neonatal Managing Editor (ME) ensures the efficient and effective operation of the editorial base and manages the editorial process for systematic reviews. This involves supporting and providing specialized editorial and technical support to review authors, editors, and associate editors. The ME works in conjunction with the coordinating editor to strategize the direction and priorities of Cochrane Neonatal and acts as a liaison with international guideline developers, such as the WHO, and performs executive and innovative functions within Cochrane. Currently, members of the Cochrane Neonatal editorial team can be found in Canada, Colombia, the United Kingdom, Australia, Malaysia, and the United States. Cochrane Neonatal consists of over 1000 review authors from 45 countries around the world.
The World Health Organization (WHO) and International Coalition of Medicines Regulatory Authorities (ICMRA) have issued a joint statement calling on the pharmaceutical industry to increase transparency and access to clinical data for all new medicines and vaccines.
Dr Karla Soares-Weiser, Editor in Chief of The Cochrane Library and Acting CEO of Cochrane, said:
“Cochrane is an advocate for greater clinical trial transparency and supports the statement issued by WHO and ICMRA calling on the pharmaceutical industry to provide wider access to research data for new medicines.
COVID-19 has highlighted the importance of timely access to detailed clinical trial data for building public trust and for assessing the quality of studies. Sharing this information has clear benefits to public health and research integrity.
When trial results are not published, or are overly redacted, the ability to make truly evidence-informed decisions about healthcare is jeopardised. This puts people at risk of harm and contributes to research waste.”
Featured Review: The impact of medications with anticholinergic effects on future problems with memory and thinking
In this recently published Cochrane review, the author team explored whether taking a certain type of medication could make older people more likely to develop dementia.
Discussing the review, Terry Quinn, senior author, said: "Almost every week we see a newspaper headline describing something new that allegedly causes or protects against dementia. These features attract attention as we all want to protect our brain health, but there is often little science behind the headlines.
There has been a lot of recent interest around whether certain prescribed medications can cause dementia. A class of medication frequently implicated in causing dementia are the ‘anticholinergics’. Medications with anticholinergic effects are commonly prescribed for conditions like hayfever, asthma, and urinary problems.
In this review we collated all the published evidence around anticholinergic prescribing and future risk of dementia. We found that taking anticholinergic medication long-term is associated with an increased risk of future dementia, and the more anticholinergic medications taken, the bigger the risk.
Reviews that look at whether a factor can predict future health require a different approach to the standard systematic review. These prognosis reviews are a relatively new method for Cochrane but are incredibly important for the dementia field.
So, should people taking anticholinergic medications be worried? At the individual level, the risk of dementia was small and many of the included studies had issues that weakened the credibility of the results. However, older adults taking anticholinergic medications may wish to discuss with their healthcare provider whether their anticholinergic medications are still needed."
What was the aim of this review?
Medicines can be classified by their ability to block the action of a chemical signalling system in the body called the cholinergic system. Medicines that do this are said to have anticholinergic effects. There are various measurement scales to quantify the effects of anticholinergic medicines. The overall anticholinergic effect caused by all the anticholinergic medications a person is taking is referred to as 'anticholinergic burden.'
We aimed to investigate if older people who have no problems with memory or thinking are more likely to develop dementia when prescribed anticholinergic medicines than people who are not prescribed these medicines.
Anticholinergic burden ratings can vary with the scale used because different scales score medicines in different ways. Therefore, we also wanted to know if any particular anticholinergic burden measurement scale was more strongly associated with increased risk of dementia than other scales.
There may be a link between anticholinergic medicine use and future risk of dementia. However, there are limitations in the published evidence, and we cannot say definitively if dementia is caused by the anticholinergic medicines themselves or by other factors. There were too few studies to allow us to compare the various anticholinergic measurement tools.
What was studied in the review?
There are more than 40 million older people worldwide living with dementia. These numbers are expected to rise to over 100 million by 2050 and at present there are very limited treatment options available. Therefore, it is important to identify factors that may increase the risk of dementia.
Because the cholinergic system in the brain plays an important role in learning and memory, there are theoretical reasons to believe that medications with anticholinergic effects could cause future dementia. Research has suggested that these medications may have unintended effects on memory and thinking, potentially resulting in dementia. If this is the case, one way to reduce the numbers of older people who develop dementia may be to avoid prescribing these medicines. Many commonly used medications have anticholinergic effects, for example medications for hay fever, insomnia (difficulty getting to sleep or staying asleep for long enough to feel refreshed), and depression.
In this review, the author team investigated the link between anticholinergic medicines, as measured by various measurement scales, and future dementia.
What were the main results of the review?
Review authors found 25 studies, including 968,428 people aged 50 years or more. Despite the relatively large number of studies, differences in design and methods only allowed authors to combine a few of them in analyses. They found that there is a consistent link between use of anticholinergic medicines and risk of future dementia. They cannot say if these medicines play a causal role; however, if they do, taking these medicines could potentially double a person's risk of dementia.
Of the anticholinergic measurement scales available, the author team could assess one commonly used tool – the 'Anticholinergic Cognitive Burden scale.' If this scale identified someone as having high anticholinergic burden, the risk of future dementia was more than two times higher than for someone with no anticholinergic burden.
The evidence included in this review was of a low quality overall and may have exaggerated the strength of the association between anticholinergic medicines and dementia. For example, anticholinergic medicines may be prescribed for the early symptoms of dementia. This would give a strong link but would not imply that the medicine caused the memory problems. Similarly, there is a risk that studies are only published when they show an association between anticholinergic medicines and future dementia. It may be that the only way to truly establish if anticholinergic medications are associated with future dementia would be to conduct a study where some people have their anticholinergic medications stopped or changed to an alternative and others continue their usual medications.
How up to date was this review?
The authors searched for studies published up to 24 March 2021.
In this author interview, lead authors Nick Meader and Andrew Moriarity tell us about this recently published Cochrane review, how they worked with a patient advisory group, and how they rose to the challenge of this being their first prognostic review, and the first of this type for Cochrane Common Mental Disorders.
Nick Meader: According to the World Health Organization (WHO), depression is the leading cause of disability worldwide and, during the pandemic, depression symptoms have increased in many countries.
We have effective treatments for depression (like antidepressants and cognitive behavioural therapy). So, a substantial number of people will no longer have symptoms of depression. But about half of those who improve will later experience a relapse or recurrence (become unwell again after an initial improvement). For most of these, relapse or recurrence occurs within a year of an improvement in symptoms.
We wanted to investigate whether there are methods to help identify which people are more likely to experience a relapse or recurrence.
Andrew Moriarty: As a GP, I routinely see the personal impacts of relapse and recurrence of depression. We want to provide strategies to prevent relapse for all patients, but in reality there are all sorts of reasons why this might not happen. Reasons might include resource availability, knowledge of health care professionals, or patient preferences, among others. So until we achieve optimal on-going depression management for all, at least if we can accurately and reliably identify those at higher risk, interventions could be more effectively targeted at those who need them most.
Researchers have started to try find ways to more accurately predict relapse and recurrence by developing prognostic models. Prognostic models combine information from several prognostic factors (also known as predictors) to provide individualised risk predictions. In practice, this would usually involve a healthcare professional entering the values for a number of different predictors – a patient’s age or details of their medical history, for example – and being provided with a risk prediction score for that patient as an output. It is essential for these risk predictions to be reliable, as otherwise wrong clinical decisions could be made based on a person’s predicted risk. This review aimed to identify all prognostic models developed to identify relapse or recurrence of depression.
What did you find out?
AM: We identified ten different prognostic models. These models had been developed across different settings (primary care, secondary care and community settings) with a whole range of different predictors included. Some of these were fairly established predictors (for example, history of previous relapse) and some were less common (such as blood test markers or results of psychological assessments). Only four of the models had undergone ‘external validation’, which means testing of their accuracy and reliability by making predictions in new groups of people and settings.
Some of the models appeared to be potentially good at predicting, but ten out of eleven studies had a high risk of bias, meaning that we need to be careful about how much we can trust the results due to concerns of methodology or gaps in information reported. At present, existing models are unlikely to reliably predict an individual’s risk of relapse or recurrence. There is a need for better quality prognostic model studies for relapse and recurrence of depression.
NM: For me, the surprising finding from our review was how little we can conclude from current research. This partly reflects that research is at an early stage, so we found only 11 studies. It’s also the case that methods are rapidly developing. So with these developments future studies will likely help us to be more confident in their findings.
Many of the studies had significant limitations. For example, studies often did not include enough people in their research. Another key problem was that only 4 studies provided an external validation of their prediction model. If you develop a prediction model from a particular group of people it may work very well on predicting relapse for these people. But what we really want to know is if the model works equally well if we use it to predict relapse in depression for a different group of people.
Without external validation, it is very difficult to know how well the model will apply when used in real life settings. This is a common limitation in prognostic modelling studies and we need more of these types of studies in the future.
As a GP, what do you find most interesting about this study?
AM: Most people who seek help for depression are seen in primary care by GPs. Like most GPs, I feel very comfortable discussing options with people with depression and reaching shared decisions about care. The guidance and evidence is reasonably clear, with room for patient choice. The guidance around what should be offered to people once they have improved, to prevent a relapse, is much less clear. Information on how to identify people who are at higher risk is minimal and there are no evidence-based tools in practice to assist with this.
It’s interesting to me that there have been several efforts to develop prediction tools. It seems to me that such a tool would be very useful in primary care to be used by GPs. However, to be used successfully, a prediction tool must be practical and simple to implement in the real world. It would also need to avoid requiring GPs to spend time gathering a significant amount of extra information. Even if we could be more certain about how well the models identified in this review predict relapse, a lot of the predictors included in the models would not be available to GPs. The potential trade-offs between usability and accuracy are critical for me to consider as a GP. The rest of my fellowship is going to explore this further, and I am going to talk to people with a history of depression and GPs about the results.
I understand you worked with a patient advisory group. How were they involved and what did you take away from their involvement?
AM: An excellent patient advisory group has been involved in this project from the early days of applying for funding. They have kept us focussed on asking the right questions and thinking about how best to use the results. The patient advisory group also read and commented on our Plain Language Summary to ensure that the review is accessible to a lay audience and will continue to advise us on how to disseminate the results more widely. An early realisation for me in discussing this with the group was that, while the subject of prognosis and prognostic modelling is quite technical, the real world implications are potentially very tangible and would have a direct effect on patients. The discussion has been lively and the questions raised were: do such models exist? If so, do they work? And if they work, why are they not being used?
This review has not definitively answered the question of whether relapse prediction is possible, but has put us in stronger position to begin to address these questions. Some of the studies suggest it might be possible to develop a reliable tool and report potentially good predictive accuracy, but weaknesses in the methodology mean we can’t fully trust the results. It might be that we can’t predict relapse, in which case we should make sure that we are doing our best to prevent it from occurring. Our patient advisory group will continue to point us in the right direction.
This is one of the first prognosis reviews on this topic (and the first for Cochrane Common Mental Disorders). Methodologically, how did you find working on this?
I feel really lucky to have worked on one of the first Cochrane Prognosis reviews and it was particularly good fun working on the first for the Cochrane Common Mental Disorders group. Nick and I attended the Cochrane Prognosis Reviews course in Utrecht back in 2019, which was great and introduced us to the different way of thinking required for these reviews. We were also fortunate to get lots of help and support from the Cochrane Prognosis Methods Group, and collaborators in the Centre for Prognosis Research at Keele. For example, we have used the novel PROBAST tool for risk of bias assessment, which I think has worked really well in providing an objective way to assess the quality of each study.
Literature searching is trickier than for most interventions reviews as the prognostic model studies tend to be less consistently labelled. However, again there is a huge amount of work going on to improve methodological standards of prognosis research and we have been lucky to have guidance on searching for prognostic modelling studies available to us. I hope our review can be helpful to other authors considering undertaking a Cochrane Prognosis Review.
NM: I enjoyed the challenge of reviewing prognostic models. I’ve learnt a lot from this process – we went on a great course at the University of Utrecht. Applying these skills in our review has been very satisfying.
In many ways the methods are just an extension of those we use in more traditional reviews. But I’ve found it really fun grappling with the challenges of prognostic modelling studies which can be quite different from those faced in clinical trials.
I’ve also enjoyed working with Andrew on this, as he has the mind of a clinician and also a researcher. So as researchers, we often approach the question in a similar way, but we also have complementary skills (he’s a GP and I’m a statistician) so it’s worked well.
What research is needed in the future?
NM: I think this is an exciting area of research where the evidence is beginning to accumulate. There are probably two main areas of need in future studies.
First, I think we are seeing an improvement in methods over time in this area. We’d like to see future studies building on these improvements. For example, by planning to study enough people so that we can draw more confident conclusions about how well the model predicts relapse. We’d also like to see more external validations of these models.
Secondly, there is also a need for further work on identifying what are the key factors for predicting depression relapse. We hope to address some of the research needs in an upcoming study which Andrew is leading on as part of his Doctoral fellowship.
AM: Speaking from a clinical perspective, the important thing for me is that we find a way to improve outcomes and quality of life for patients. Part of that might involve improving the ability to predict relapse. If we find that we can reliably predict relapse, we also have to then be able to do something to prevent it. We’re likely to need to refine and develop existing interventions into something scalable that can be implemented into practice. In addition to the work we have planned attempting to improve risk prediction, Nick and I are going to work together with some of the wider team on a follow-up Cochrane review of interventions for preventing relapse in primary care – I’m looking forward to it!
This review forms part of Andrew’s National Institute for Health Research (NIHR) Doctoral Research Fellowship, which investigates relapse and recurrence of depression. It was a collaboration between colleagues at the University of York, the Hull York Medical School and Keele University.
The Basement Science is a podcast hosted by science students who share their excitement about science and science communication. They have conversations with scientists and other guests with the aim of making complicated ideas understandable to non-scientists, while showing why science matters.
They are speaking to members of Cochrane over three episodes:Episode 1 - Cochrane Reviews in times of COVID-19 with Dr John Lavis
Tomàs Garnier & Lea Urpa interview Dr. John Lavis. John is a member of the Cochrane editorial board, member of the Cochrane knowledge-translation advisory group, and founder and director of the McMaster Health Forum, which hosts COVID-END. John speaks about what we know about COVID-19 so far, the importance of evidence synthesis and Living Systematic Reviews, how the media covers science, and Cochrane's Plain Language Summaries, translation work, and how Cochrane works with patients and careers.
Next up in the series of podcasts with the Science Basement:
- Episode 2 - How scientists collect and filter information: What are systematic reviews and how they are made – with Cochrane author Fiona Stewart.
- Episode 3 - How can the audience filter information: How can non-scientists make a sense of all the information available – with Jack Nunn, member of Cochrane's Consumer Network Executive and part of our Cochrane Advocacy Advisory group.
Featured Review: Combination fixed-dose beta agonist and steroid inhaler as required for adults or children with mild asthma
Cochrane Airways works with authors (typically clinicians and researchers) to produce systematic reviews on chronic obstructive pulmonary disease (COPD), bronchiectasis and other lung diseases, and asthma.
We asked Dr Timothy Hinks, one of the Cochrane Review authors, about the findings of this recent review.
For those with mild asthma, there are different types of inhaler. What’s the difference?
There are two main types of inhaled medications for asthma. ‘Relievers’ treat just the symptoms by relaxing the constricted airways, these medicines are ‘beta-agonists’, some of which are fast-acting (FABA) and provide symptom relief within 5-10 minutes. ‘Preventers’ are inhaled corticosteroids, which treat the underlying inflammation causing asthma. Inhaled steroids are very effective in reducing severe attacks of asthma and asthma deaths, but they need to be taken for several days at a time before people begin to feel the effects. Both medications are important and helpful. These different types of medicines were originally given in two separate inhaler devices and someone with asthma needed to use two different inhalers. This caused a problem that many people depended too much on the reliever inhalers because they provide rapidly relief of symptoms, but this can lead some people not to take as much of the preventer inhalers as needed to effectively treat the underlying problem, increasing the risk of severe asthma attacks, and hospitalisation or death.
In recent years inhalers have become available which contain both the beta-agonist and the inhaled corticosteroids in a single device. Combination inhalers have proved very effective in moderate and severe asthma, but till now it was not known whether they might be the best way to treat people with mild asthma – who make up the majority of people who suffer from asthma.
Tell us more about this review; why did you think it was important to do it?
We looked at the use of combination inhalers in mild asthma using a strategy where the inhaler is only used when people experience symptoms. We compared this with two current approaches to treatment: just using a reliever when needed, or using a reliever when needed on top of regular daily use of a preventer. We chose to do this study now because several recent large clinical trials have reported in the last 3 years which directly addressed this question. Consequently several national and international guidelines are being revised to reflect the findings of the study. We aimed to provide an objective, global review of the available evidence to inform decision makers, clinicians and people with asthma.
What did the review find?
We found that combination inhalers used as-needed reduced severe exacerbations requiring tablet steroids and rates of emergency admission to hospital with asthma symptoms when compared with reliever-only treatment.
Combination inhalers used as-needed were as effective as daily preventative steroid inhalers. People using combination inhalers as-required had lower rates of hospital admission and overall used a lower total inhaled steroid dose.
What’s the core message for clinicians and patients?
These findings suggest that as-required use of combination inhalers is an effective and safe approach to the treatment of mild asthma, and could reduce the number of severe asthma attacks. This is important as asthma is a major cause of time off work, economic costs, and chronic ill health and it remains a largely preventable cause of death for 400,000 people per year globally. This approach also simplifies treatment regimes and could reduce contradictory or ambiguous messages to people with asthma. It would support adoption of this strategy in current guidelines. However cost frequently limits the availability of these inhalers in many low and middle income countries, who rely heavily on reliever therapies or tablet steroids instead. We need further pragmatic studies and healthcare cost assessments in such countries to support equitable access to affordable quality-assured asthma medicines.
Featured Review: Paying for performance to improve the delivery of healthcare services in low- and middle-income countries
A recently published review from Cochrane Effective Practice and Organisation of Care (EPOC) Group looks at the effects of ‘pay for performance’ strategies on the delivery of healthcare services in low- and middle-income countries.
Karin Diaconu, first author of this review, notes, "There is growing interest in paying for performance as a strategy for aligning the work of health providers and healthcare organizations with public health goals. The volume of schemes implementing paying for performance has increased over the last decade and so has the number of studies on the effectiveness of these strategies in low- and middle-income countries.
This review brings this evidence together and asks how successful schemes are in improving health care and health. The review notes that paying for performance may have some positive effects: it may lead to increased uptake of some health services, better quality of care, and improve the availability of resources as well as improving autonomy of involved healthcare organisations."
Pay for performance strategies may have both positive and negative effects on the health services they target. These strategies may also have positive effects on other health services that are not directly targeted and may have no unintended negative effects on these services. However, most of this evidence is of low certainty and we need more, well-conducted studies on this topic.
What is ‘pay for performance’?
In a 'pay for performance' approach, people are given money or other rewards if they carry out a particular task or meet a particular target. This strategy is usually directed at health workers or healthcare organizations. The health workers or healthcare organizations are rewarded if they offer particular services or deliver care that is of a certain quality, or if their patients use particular services and achieve better health as a result.
Planners use these strategies to target specific health problems and services that need improvement. But it is also possible that pay for performance strategies have positive or negative effects, including on other services that are not specifically targeted. For instance, these strategies could lead health workers to improve the quality of the other services they deliver. But it could also lead them to avoid services that do not give extra payment. To find out more, the review authors assessed the effects of paying for performance on both targeted and untargeted services. This included looking for any unintended effects of the strategies.
What are the main results of the review?
The review included 59 relevant studies. Most were from sub-Saharan Africa and Asia. Most of the pay for performance schemes in the studies were funded by national Ministries of Health, also with support of the World Bank.
Forty-nine studies compared health facilities that used pay for performance strategies to health facilities who were doing business as usual. Seventeen studies compared health facilities that used pay for performance strategies to facilities that used other strategies. In most of these studies, health facilities using pay for performance strategies were compared to facilities who were given the same amount of funds but without a pay for performance element.
The effects of paying for performance compared to business as usual
For health services that are specifically targeted, pay for performance strategies:
- may improve health outcomes, may improve service quality and probably increase the availability of health workers, medicines and well-functioning infrastructure and equipment
- but may have both positive and negative effects on the delivery and use of health services
For health services that are untargeted, pay for performance strategies:
- probably improve some health outcomes
- may improve the delivery, use and quality of some health services but may make little or no difference to others
- may have few or no unintended effects
- we don’t know what the effects of pay for performance are on the availability of medicines and other resources because the evidence was of very low certainty
The effects of paying for performance compared to other strategies
For health outcomes and services that are specifically targeted, pay for performance strategies:
- may improve service quality
- may make little or no difference to health outcomes
- may have mixed effects on the delivery and use of health services and on the availability of equipment and medicines, including both positive and negative effects
For health outcomes and services that are untargeted, pay for performance strategies:
- may make little or no difference to health outcomes and to the delivery and use of health services
- we don’t know what the effects of pay for performance are on service quality, on the availability of resources, and on unintended effects because the evidence was missing or of very low certainty
How up to date is this review?
The review authors included studies that had been published up to April 2018.