Emma J Welsh

When and how to update systematic reviews: consensus and checklist.

Updating of systematic reviews is generally more efficient than starting all over again when new evidence emerges, but to date there has been no clear guidance on how to do this. This guidance helps authors of systematic reviews, commissioners, and editors decide when to update a systematic review, and then how to go about updating the review.

Cochrane Airways Group reviews were prioritized for updating using a pragmatic approach.

OBJECTIVES Cochrane Reviews should address the most important questions for guideline writers, clinicians, and the public. It is not possible to keep all reviews up-to-date, so the Cochrane Airways Group (CAG) decided to prioritize updates and new reviews without requesting additional resources. The aim of the objective was to develop pragmatic and transparent prioritization techniques to identify 25 to 35 high-priority updates from a total of 270 CAG Reviews and become more selective over which new reviews we publish. STUDY DESIGN AND SETTING We used elements from existing prioritization processes, including existing health care uncertainties, expert opinion, and a decision tool. We did not conduct a full face-to-face workshop or an iterative group decision-making process. RESULTS We prioritized 30 reviews in need of updating and aimed to update these within 2 years. Within the first 18 months, nine of these have been published. CONCLUSION A pragmatic approach to prioritization can indicate priority reviews without an excessive drain on time and resources. The steps provide us with better control over the reviews in our scope and can be built on in the future.

Assessing the methodological quality of systematic reviews

Dear Sirs, We read with interest the paper by Ho et al,1 which used the AMSTAR tool to assess the methodological quality of systematic reviews (SRs) on chronic obstructive pulmonary disease (COPD). As staff at the Cochrane Airways Group with the responsibility of producing high-quality SRs for airway conditions, including COPD, we are always happy to hear how we could improve. However, there are some methodological issues within the study. The abstract states that the methodological quality of the reviews was disappointing and emphasises the more negative findings, neglecting the positive results (e.g., a priori design in 67% SRs, comprehensive literature search in 97% and scientific quality assessed and documented in 85%). The authors did not complete the AMSTAR ratings in duplicate; yet, duplicate data extraction is a mark of a good SR. Our experience with this tool is that the discussion between two or more people helps reach a fair judgement.2 It would have been helpful to see the AMSTAR ratings per review so that the work could be replicated and evaluated. We noted the lack of discussion about the choice to limit the study to SRs that include a meta-analysis. Choosing not to perform a meta-analysis when there is a lot of heterogeneity between studies is a valid decision. The authors highlighted that non-English databases were searched infrequently. This is not an AMSTAR criterion; have the authors suggested that this be incorporated in any update of the tool? Cochrane does not require that non-English language databases be searched and this is usually done only when we expect that this will yield additional relevant trials. We agree that multilingual SR teams are advantageous and we would be grateful if people who wish to translate the trial reports for inclusion in Cochrane reviews contact us. We take the authors’ point about being clearer about reviewers’ support, and making a statement about publication bias in the results section as well as the methods section when there are too few studies to permit a funnel plot. As highlighted in the paper, the quality of SRs has improved significantly in recent years through the development of methods and improved implementation.3,4 It would have been helpful to highlight this important point in the conclusions and abstract.

How to make sense of a Cochrane systematic review

More and more papers are published in medical journals every day, so how do you decide which ones to read and, having read a paper, how do you decide whether to change your practice as a result of what you have read? Perhaps the paper was atypical in some way. What does the other research on the topic say? The purpose of systematic reviews is to summarise all the available, high-quality evidence that can be found on a particular topic. A narrative review, in which an expert can cite a selection of papers that support a particular viewpoint, says very little about the papers that do not. In contrast, a systematic review involves a search for all available literature, whatever the findings may be. Systematic reviews start with a well-defined clinical question, and aim to identify, appraise, synthesise and then apply all the available good-quality evidence that can be found (published or unpublished) that is relevant to the question. In particular, Cochrane systematic reviews have to meet a defined set of quality standards and the authors and editors set out to make them the best around. They are the current gold standard in the systematic review field. The Cochrane Collaboration is an international group which is now 20 years old. The collaboration depends upon the voluntary contribution of thousands of authors and is supported by editorial bases and methodologists. In the UK, these bases are supported by funding from the National Institute of Health Research (NIHR), and any funding for editorial bases must be free from commercial interests. Review groups are divided up into areas of clinical interest and, within the respiratory field, there are groups for lung cancer (based in France), acute respiratory infections (based in Australia), cystic fibrosis (based in the UK) and airways (based in the UK …

“Asthma can take over your life but having the right support makes that easier to deal with.” Informing research priorities by exploring the barriers and facilitators to asthma control: a qualitative analysis of survey data

BackgroundInvolving patients and the public in research prioritisation is important. Cochrane Airways works with authors to produce systematic reviews of evidence related to chronic airways disease. Cochrane Airways has undertaken activities to identify research priorities, including workshops with stakeholders and consultation with experts. We present the findings of an online survey, designed to align our work with the priorities of people affected by asthma.MethodsWe promoted a survey comprising open-ended questions via social media to people affected by asthma. We compiled the free-text responses and conducted an exploratory thematic analysis to identify important barriers and facilitators to asthma control. We triangulated findings with other research prioritisation activities to produce new review questions.ResultsWe received 57 survey responses. Eight main themes emerged, most encompassing both facilitators and barriers: attitudes and knowledge; financial costs; environmental factors and triggers; healthcare systems; lifestyle factors; medication; self-care; and support. Barriers were more frequently mentioned than facilitators and many related to healthcare systems.ConclusionsThese findings offer valuable insights into the challenges faced by individuals affected by asthma in the UK, and possibly further afield. We developed a list of priority reviews based on what was said by people in this survey and at a workshop. This demonstrates the real impact that people affected by asthma have on the research agenda of Cochrane Airways. Over the next 2–3 years we will produce reviews that address some of these questions hopefully leading to health benefits.

20 Years of Cochrane Glancing backwards – Moving ahead: a tale of two Cochrane Review Groups

The Cochrane Collaboration is widely recognised as setting the gold standard for assessing and reporting research to determine the effectiveness of different healthcare treatments and interventions. It is a not-for-profit, global network of approximately 28,000 contributors in more than 120 countries, the majority of whom are volunteers (there are only 500 paid staff). There are over 22,500 contributing review authors; and approximately 5100 of Cochrane contributors are located in countries with lowand middle-income economies. Currently over 5400 reviews are published in The Cochrane Library, with another 2300 reviews underway. More than half the world’s population already has one-click access to Cochrane Review content through licenses or free access through the lowand middle-income countries programme. All Cochrane Reviews and updates published from February 2013 will be available on an open access basis 12 months after publication in The Cochrane Library. With over 75 trials published each day, staying on top of the most up-to-date literature is an impossible task. For over 20 years The Cochrane Collaboration has produced systematic reviews to address questions that clinicians are asking about their practice. Cochrane Reviews distil information from all the relevant clinical trials and combine the results trying to minimise bias at each step.

Leukotriene receptor antagonists for exacerbations of asthma

Emergency department visits and hospital admissions for acute asthma represent a considerable burden on health services worldwide. Many patients presenting with acute asthma do not respond fully to standard therapy of beta2agonists, corticosteroids and oxygen so additional therapies are required. Fast-acting LTRAs may potentially be helpful but guidelines report insufficient evidence to support their use during an asthma exacerbation. This Cochrane Review looked at whether adding LTRAs to standard treatment for people having an asthma attacks in the emergency department was beneficial or not. The primary outcome was hospital admissions. We identified six trials randomising 470 children to receive monteleukast or placebo in addition to standard care (nebulised