Viral clearance as a surrogate of clinical efficacy for COVID-19 therapies in outpatients: a systematic review and meta-analysis.

BACKGROUND: Surrogates of antiviral efficacy are needed for COVID-19. We aimed to investigate the relationship between the virological effect of treatment and clinical efficacy as measured by progression to severe disease in outpatients treated for mild-to-moderate COVID-19. METHODS: In this systematic review and meta-analysis, we searched PubMed, Scopus, and medRxiv from database inception to Aug 16, 2023, for randomised placebo-controlled trials that tested virus-directed treatments (ie, any monoclonal antibodies, convalescent plasma, or antivirals) in non-hospitalised individuals with COVID-19. We only included studies that reported both clinical outcomes (ie, rate of disease progression to hospitalisation or death) and virological outcomes (ie, viral load within the first 7 days of treatment). We extracted summary data from eligible reports, with discrepancies resolved through discussion. We used an established meta-regression model with random effects to assess the association between clinical efficacy and virological treatment effect, and calculated I2 to quantify residual study heterogeneity. FINDINGS: We identified 1718 unique studies, of which 22 (with a total of 16 684 participants) met the inclusion criteria, and were in primarily unvaccinated individuals. Risk of bias was assessed as low in 19 of 22 studies for clinical outcomes, whereas for virological outcomes, a high risk of bias was assessed in 11 studies, some risk in ten studies, and a low risk in one study. The unadjusted relative risk of disease progression for each extra log10 copies per mL reduction in viral load in treated compared with placebo groups was 0·12 (95% CI 0·04-0·34; p<0·0001) on day 3, 0·20 (0·08-0·50; p=0·0006) on day 5, and 0·53 (0·30-0·94; p=0·030) on day 7. The residual heterogeneity in our meta-regression was estimated as low (I2=0% [0-53] on day 3, 0% [0-71] on day 5, and 0% [0-43] on day 7). INTERPRETATION: Despite the aggregation of studies with differing designs, and evidence of risk of bias in some virological outcomes, this review provides evidence that treatment-induced acceleration of viral clearance within the first 5 days after treatment is a potential surrogate of clinical efficacy to prevent hospitalisation with COVID-19. This work supports the use of viral clearance as an early phase clinical trial endpoint of therapeutic efficacy. FUNDING: Australian Government Department of Health, Medical Research Future Fund, and Australian National Health and Medical Research Council.

Is it possible to make 'living' guidelines? An evaluation of the Australian Living Stroke Guidelines.

BACKGROUND: Keeping best practice guidelines up-to-date with rapidly emerging research evidence is challenging. 'Living guidelines' approaches enable continual incorporation of new research, assisting healthcare professionals to apply the latest evidence to their clinical practice. However, information about how living guidelines are developed, maintained and applied is limited. The Stroke Foundation in Australia was one of the first organisations to apply living guideline development methods for their Living Stroke Guidelines (LSGs), presenting a unique opportunity to evaluate the process and impact of this novel approach. METHODS: A mixed-methods study was conducted to understand the experience of LSGs developers and end-users. We used thematic analysis of one-on-one semi-structured interview and online survey data to determine the feasibility, acceptability, and facilitators and barriers of the LSGs. Website analytics data were also reviewed to understand usage. RESULTS: Overall, the living guidelines approach was both feasible and acceptable to developers and users. Facilitators to use included collaboration with multidisciplinary clinicians and stroke survivors or carers. Increased workload for developers, workload unpredictability, and limited information sharing, and interoperability of technological platforms were identified as barriers. Users indicated increased trust in the LSGs (69%), likelihood of following the LSGs (66%), and frequency of access (58%), compared with previous static versions. Web analytics data showed individual access by 16,517 users in 2016 rising to 53,154 users in 2020, a threefold increase. There was also a fourfold increase in unique LSG pageviews from 2016 to 2020. CONCLUSIONS: This study, the first evaluation of living guidelines, demonstrates that this approach to stroke guideline development is feasible and acceptable, that these approaches may add value to developers and users, and may increase guideline use. Future evaluations should be embedded along with guideline implementation to capture data prospectively.

Poor reporting limited consideration of EDI in the Australian guidelines for the clinical care of people with COVID-19.

OBJECTIVES: Actively addressing issues of equity, diversity, and inclusion (EDI) in healthcare guidelines provides an important avenue ensure that individuals and communities receive high-quality healthcare that meets their needs. In 2020, the National Clinical Evidence Taskforce was charged with developing Australian living guidelines for COVID-19 (the Guidelines). It was intended that the Guidelines would consider the biological and social determinants of health (BSDH) underpinning evidence-based recommendations for of the treatment of COVID-19. The objective of this paper is to describe the evidence available on BSDH that is reported in published trials of disease-modifying therapies for COVID-19. STUDY DESIGN AND SETTING: Published papers of randomized controlled trials that informed clinical recommendations (for and against drug therapies for COVID-19) in the Guidelines were reviewed retrospectively using a case series design. We extracted reported characteristics relating to BSDH. These included age, sex, gender, geographical location, ethnicity (including indigenous), disability, migrant status, income, education, employment, and social support. A descriptive analysis was conducted to illustrate the characteristics available for use in guideline development. RESULTS: A total of 115 peer-reviewed papers describing randomized control trials of drug interventions for the treatment of COVID-19 were included. BSDH characteristics were poorly reported. Geographical location of the study was the only category reported in all papers. While age and sex were reported in most papers (n = 109 and 108, respectively), ethnicity was reported in only one-third of papers (n = 40), social support was reported in only three papers, and employment in one paper. No paper reported on gender, disability, migrant status, income, or education. CONCLUSION: Consideration of EDI issues is a crucial component of guideline development. Although these issues were widely recognized to impact on health outcomes from COVID-19, reporting of these characteristics was poor in COVID trials. Urgent action is needed to improve reporting of EDI characteristics if they are to be meaningfully considered in guideline processes, and health inequity is overcome.

Electronic cigarettes for smoking cessation.

BACKGROUND: Electronic cigarettes (ECs) are handheld electronic vaping devices which produce an aerosol by heating an e-liquid. People who smoke, healthcare providers and regulators want to know if ECs can help people quit smoking, and if they are safe to use for this purpose. This is a review update conducted as part of a living systematic review. OBJECTIVES: To examine the safety, tolerability and effectiveness of using electronic cigarettes (ECs) to help people who smoke tobacco achieve long-term smoking abstinence, in comparison to non-nicotine EC, other smoking cessation treatments and no treatment. SEARCH METHODS: We searched the Cochrane Tobacco Addiction Group's Specialized Register to 1 February 2023, and Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and PsycINFO to 1 July 2023, and reference-checked and contacted study authors. SELECTION CRITERIA: We included trials in which people who smoke were randomized to an EC or control condition. We also included uncontrolled intervention studies in which all participants received an EC intervention as these studies have the potential to provide further information on harms and longer-term use. Studies had to report an eligible outcome. DATA COLLECTION AND ANALYSIS: We followed standard Cochrane methods for screening and data extraction. Critical outcomes were abstinence from smoking after at least six months, adverse events (AEs), and serious adverse events (SAEs). We used a fixed-effect Mantel-Haenszel model to calculate risk ratios (RRs) with a 95% confidence interval (CI) for dichotomous outcomes. For continuous outcomes, we calculated mean differences. Where appropriate, we pooled data in pairwise and network meta-analyses (NMA). MAIN RESULTS: We included 88 completed studies (10 new to this update), representing 27,235 participants, of which 47 were randomized controlled trials (RCTs). Of the included studies, we rated ten (all but one contributing to our main comparisons) at low risk of bias overall, 58 at high risk overall (including all non-randomized studies), and the remainder at unclear risk. There is high certainty that nicotine EC increases quit rates compared to nicotine replacement therapy (NRT) (RR 1.59, 95% CI 1.29 to 1.93; I2 = 0%; 7 studies, 2544 participants). In absolute terms, this might translate to an additional four quitters per 100 (95% CI 2 to 6 more). There is moderate-certainty evidence (limited by imprecision) that the rate of occurrence of AEs is similar between groups (RR 1.03, 95% CI 0.91 to 1.17; I2 = 0%; 5 studies, 2052 participants). SAEs were rare, and there is insufficient evidence to determine whether rates differ between groups due to very serious imprecision (RR 1.20, 95% CI 0.90 to 1.60; I2 = 32%; 6 studies, 2761 participants; low-certainty evidence). There is moderate-certainty evidence, limited by imprecision, that nicotine EC increases quit rates compared to non-nicotine EC (RR 1.46, 95% CI 1.09 to 1.96; I2 = 4%; 6 studies, 1613 participants). In absolute terms, this might lead to an additional three quitters per 100 (95% CI 1 to 7 more). There is moderate-certainty evidence of no difference in the rate of AEs between these groups (RR 1.01, 95% CI 0.91 to 1.11; I2 = 0%; 5 studies, 1840 participants). There is insufficient evidence to determine whether rates of SAEs differ between groups, due to very serious imprecision (RR 1.00, 95% CI 0.56 to 1.79; I2 = 0%; 9 studies, 1412 participants; low-certainty evidence). Due to issues with risk of bias, there is low-certainty evidence that, compared to behavioural support only/no support, quit rates may be higher for participants randomized to nicotine EC (RR 1.88, 95% CI 1.56 to 2.25; I2 = 0%; 9 studies, 5024 participants). In absolute terms, this represents an additional four quitters per 100 (95% CI 2 to 5 more). There was some evidence that (non-serious) AEs may be more common in people randomized to nicotine EC (RR 1.22, 95% CI 1.12 to 1.32; I2 = 41%, low-certainty evidence; 4 studies, 765 participants) and, again, insufficient evidence to determine whether rates of SAEs differed between groups (RR 0.89, 95% CI 0.59 to 1.34; I2 = 23%; 10 studies, 3263 participants; very low-certainty evidence). Results from the NMA were consistent with those from pairwise meta-analyses for all critical outcomes, and there was no indication of inconsistency within the networks. Data from non-randomized studies were consistent with RCT data. The most commonly reported AEs were throat/mouth irritation, headache, cough, and nausea, which tended to dissipate with continued EC use. Very few studies reported data on other outcomes or comparisons, hence, evidence for these is limited, with CIs often encompassing both clinically significant harm and benefit. AUTHORS' CONCLUSIONS: There is high-certainty evidence that ECs with nicotine increase quit rates compared to NRT and moderate-certainty evidence that they increase quit rates compared to ECs without nicotine. Evidence comparing nicotine EC with usual care/no treatment also suggests benefit, but is less certain due to risk of bias inherent in the study design. Confidence intervals were for the most part wide for data on AEs, SAEs and other safety markers, with no difference in AEs between nicotine and non-nicotine ECs nor between nicotine ECs and NRT. Overall incidence of SAEs was low across all study arms. We did not detect evidence of serious harm from nicotine EC, but the longest follow-up was two years and the number of studies was small. The main limitation of the evidence base remains imprecision due to the small number of RCTs, often with low event rates. Further RCTs are underway. To ensure the review continues to provide up-to-date information to decision-makers, this review is a living systematic review. We run searches monthly, with the review updated when relevant new evidence becomes available. Please refer to the Cochrane Database of Systematic Reviews for the review's current status.

Barriers to and facilitators of living guidelines use in low-income and middle-income countries: a scoping review.

INTRODUCTION: Living guidelines provide reliable, ongoing evidence surveillance and regularly updated recommendations for healthcare decision-making. As a relatively new concept, most of the initial application of living approaches has been undertaken in high-income countries. However, in this scoping review, we looked at what is currently known about how living guidelines were developed, used and applied in low-income and middle-income countries. METHODS: Searches for published literature were conducted in Medline, Global Health, Cochrane Library and Embase. Grey literature was identified using Google Scholar and the WHO website. In addition, the reference lists of included studies were checked for missing studies. Studies were included if they described or reflected on the development, application or utility of living guideline approaches for low-income and middle-income countries. RESULTS: After a full-text review, 21 studies were included in the review, reporting on the development and application of living recommendations in low-income and middle-income countries. Most studies reported living guideline activities conducted by the WHO (15, 71.4%), followed by China (4, 19%), Chile (1, 4.8%) and Lebanon (1, 4.8%). All studies based on WHO reports relate to living COVID-19 management guidelines. CONCLUSIONS: Most of the studies in this review were WHO-reported studies focusing solely on COVID-19 disease treatment living guidelines. However, there was no clear explanation of how living guidelines were used nor information on the prospects for and obstacles to the implementation of living guidelines in low-income and middle-income countries.

Exploring the use and impact of the Australian living guidelines for the clinical care of people with COVID-19: where to from here?

OBJECTIVES: The Australian National COVID-19 Clinical Evidence Taskforce has been developing, maintaining, and disseminating living guidelines and decision support tools (clinical flowcharts) for the care of people with suspected or confirmed COVID-19 since 2020. Living guidelines, a form of living evidence, are a relatively new approach; hence, more work is required to determine how to optimize their use to inform practice, policy, and decision-making and to explore implementation, uptake, and impact implications. An update of an earlier impact evaluation was conducted to understand sustained awareness and use of the guidelines; the factors that facilitate the widespread adoption of the guidelines and to explore the perceived strengths and opportunities for improvement of the guidelines. STUDY DESIGN AND SETTING: A mixed-methods impact evaluation was conducted. Surveys collected both quantitative and qualitative data and were supplemented with qualitative interviews. Participants included Australian healthcare practitioners providing care to individuals with suspected or confirmed COVID-19 and people involved in policy-making. Data were collected on awareness, use, impact, strengths, and opportunities for improvement of the guidelines and flow charts. RESULTS: A total of 148 participants completed the survey and 21 people were interviewed between January and March 2022. Awareness of the work of the Taskforce was high and more than 75% of participants reported that the guidelines were used within their workplace. Participants described the Taskforce website and guidelines as trustworthy, valuable, and reliable sources of up-to-date evidence-based information. The evaluation highlighted the varied ways the guidelines were being used across a range of settings and the diverse impacts they have from those at a clinical level to impacts at a policy level. Barriers to and enablers of impact and uptake of the guideline were explored. CONCLUSION: This evaluation highlights the value of living guidelines during a pandemic when the evidence base is rapidly changing and expanding. It presents useful understanding of the ways clinicians and others use living evidence to inform their clinical practice and decision-making and the diverse impacts the guidelines are having around Australia.

Optimizing process and methods for a living systematic review: 30 search updates and three review updates later.

OBJECTIVE: To describe the living systematic review (LSR) process and to share experience of planning, searches, screening, extraction, publishing and dissemination to inform and assist authors planning their own LSR. Many LSR do not publish more than one update, we hope this paper helps to increase this. STUDY DESIGN AND SETTING: A Cochrane LSR with an international author team that has been 'living' for two years, with monthly search updates and three full updates published in this time. LSRs are regularly updated systematic reviews that allow new evidence to be incorporated as it becomes available. LSR are ideally suited to policy-relevant topics where there is uncertainty and new evidence will likely impact the interpretation and/or certainty of outcomes. RESULTS: The key features of the process that require consideration are: specifying the frequency of searches and triggers for full updates in the protocol; stakeholder input; publishing and disseminating monthly search findings. A strong team, incorporating methodological and topic expertise, with core members that meet regularly is essential. Regular search updates make it important to have a clear cyclical schedule of activity. To achieve timely updates this process should be streamlined, for example, using automated monthly searches, and systematic reviewing software for screening. LSR provide a unique opportunity to incorporate stakeholder feedback. CONCLUSIONS: We recommend that LSRs should be: justified; carefully planned including the timing of search updates, triggers for publication and termination; published in a timely manner; have a clear dissemination plan; and a strong core team of authors.

Living evidence and adaptive policy: perfect partners?

BACKGROUND: While there has been widespread global acceptance of the importance of evidence-informed policy, many opportunities to inform health policy with research are missed, often because of a mismatch between when and where reliable evidence is needed, and when and where it is available. 'Living evidence' is an approach where systematic evidence syntheses (e.g. living reviews, living guidelines, living policy briefs, etc.) are continually updated to incorporate new relevant evidence as it becomes available. Living evidence approaches have the potential to overcome a major barrier to evidence-informed policy, making up-to-date systematic summaries of policy-relevant research available at any time that policy-makers need them. These approaches are likely to be particularly beneficial given increasing calls for policy that is responsive, and rapidly adaptive to changes in the policy context. We describe the opportunities presented by living evidence for evidence-informed policy-making and highlight areas for further exploration. DISCUSSION: There are several elements of living approaches to evidence synthesis that might support increased and improved use of evidence to inform policy. Reviews are explicitly prioritised to be 'living' by partnerships between policy-makers and researchers based on relevance to decision-making, as well as uncertainty of existing evidence, and likelihood that new evidence will arise. The ongoing nature of the work means evidence synthesis teams can be dynamic and engage with policy-makers in a variety of ways over time; and synthesis topics, questions and methods can be adapted as policy interests or contextual factors shift. Policy-makers can sign-up to be notified when relevant new evidence is found, and can be confident that living syntheses are up-to-date and contain all research whenever they access them. The always up-to-date nature of living evidence syntheses means producers can rapidly demonstrate availability of relevant, reliable evidence when it is needed, addressing a frequently cited barrier to evidence-informed policymaking. CONCLUSIONS: While there are challenges to be overcome, living evidence provides opportunities to enable policy-makers to access up-to-date evidence whenever they need it and also enable researchers to respond to the issues of the day with up-to-date research; and update policy-makers on changes in the evidence base as they arise. It also provides an opportunity to build flexible partnerships between researchers and policy-makers to ensure that evidence syntheses reflect the changing needs of policy-makers.

Evidence surveillance for a living clinical guideline: Case study of the Australian stroke guidelines.

BACKGROUND: Continual evidence surveillance is an integral feature of living guidelines. The Australian Stroke Guidelines include recommendations on 100 clinical topics and have been 'living' since 2018. OBJECTIVES: To describe the approach for establishing and evaluating an evidence surveillance system for the living Australian Stroke Guidelines. METHODS: We developed a pragmatic surveillance system based on an analysis of the searches for the 2017 Stroke Guidelines and evaluated its reliability by assessing the potential impact on guideline recommendations. Search retrieval and screening workload are monitored monthly, together with the frequency of changes to the guideline recommendations. RESULTS: Evidence surveillance was guided by practical considerations of efficiency and sustainability. A single PubMed search covering all guideline topics, limited to systematic reviews and randomised trials, is run monthly. The search retrieves about 400 records a month of which a sixth are triaged to the guideline panels for further consideration. Evaluations with Epistemonikos and the Cochrane Stroke Trials Register demonstrated the robustness of adopting this more restrictive approach. Collaborating with the guideline team in designing, implementing and evaluating the surveillance is essential for optimising the approach. CONCLUSION: Monthly evidence surveillance for a large living guideline is feasible and sustainable when applying a pragmatic approach.

Determinants of passive antibody efficacy in SARS-CoV-2 infection: a systematic review and meta-analysis.

BACKGROUND: Randomised controlled trials of passive antibodies as treatment and prophylaxis for COVID-19 have reported variable efficacy. However, the determinants of efficacy have not been identified. We aimed to assess how the dose and timing of administration affect treatment outcome. METHODS: In this systematic review and meta-analysis, we extracted data from published studies of passive antibody treatment from Jan 1, 2019, to Jan 31, 2023, that were identified by searching multiple databases, including MEDLINE, PubMed, and ClinicalTrials.gov. We included only randomised controlled trials of passive antibody administration for the prevention or treatment of COVID-19. To compare administered antibody dose between different treatments, we used data on in-vitro neutralisation titres to normalise dose by antibody potency. We used mixed-effects regression and model fitting to analyse the relationship between timing, dose and efficacy. FINDINGS: We found 58 randomised controlled trials that investigated passive antibody therapies for the treatment or prevention of COVID-19. Earlier clinical stage at treatment initiation was highly predictive of the efficacy of both monoclonal antibodies (p<0·0001) and convalescent plasma therapy (p=0·030) in preventing progression to subsequent stages, with either prophylaxis or treatment in outpatients showing the greatest effects. For the treatment of outpatients with COVID-19, we found a significant association between the dose administered and efficacy in preventing hospitalisation (relative risk 0·77; p<0·0001). Using this relationship, we predicted that no approved monoclonal antibody was expected to provide more than 30% efficacy against some omicron (B.1.1.529) subvariants, such as BQ.1.1. INTERPRETATION: Early administration before hospitalisation and sufficient doses of passive antibody therapy are crucial to achieving high efficacy in preventing clinical progression. The relationship between dose and efficacy provides a framework for the rational assessment of future passive antibody prophylaxis and treatment strategies for COVID-19. FUNDING: The Australian Government Department of Health, Medical Research Future Fund, National Health and Medical Research Council, the University of New South Wales, Monash University, Haematology Society of Australia and New Zealand, Leukaemia Foundation, and the Victorian Government.

What could health technology assessment learn from living clinical practice guidelines?

A "living" approach to clinical practice guidelines is when the identification, appraisal and synthesis of evidence is maintained and repeated at an agreed frequency, with a clear process for when and how new evidence is to be incorporated. The value of a living approach to guidelines was emphasised during the COVID-19 pandemic when health professionals and policymakers needed to make decisions regarding patient care in the context of a nascent but rapidly evolving evidence base. In this perspective, we draw on our recent experience developing Australian and international living guidelines and reflect on the feasibility of applying living guideline methods and processes to a lifecycle approach to health technology assessment (HTA). We believe the opportunities and challenges of adopting a living approach in HTA fall into five key themes: identification, appraisal and synthesis of evidence; optimising the frequency of updates; embedding ongoing multi-stakeholder engagement; linking the emergence of new evidence to reimbursement; and system capacity to support a living approach. We acknowledge that the suitability of specific living approaches to HTA will be heavily influenced by the type of health technology, its intended use in the health system, local reimbursement pathways, and other policy settings. But we believe that the methods and processes applied successfully to guideline development to manage evidentiary uncertainty could be applied in the context of HTA and reimbursement decision-making to help manage similar sources of uncertainty.

Are COVID-19 systematic reviews up to date and can we tell? A cross-sectional study.

BACKGROUND: COVID-19 led to a rapid acceleration in the number of systematic reviews. Readers need to know how up to date evidence is when selecting reviews to inform decisions. This cross-sectional study aimed to evaluate how easily the currency of COVID-19 systematic reviews published early in the pandemic could be determined and how up to date these reviews were at the time of publication. METHODS: We searched for systematic reviews and meta-analyses relevant to COVID-19 added to PubMed in July 2020 and January 2021, including any that were first published as preprints. We extracted data on the date of search, number of included studies, and date first published online. For the search date, we noted the format of the date and where in the review this was reported. A sample of non-COVID-19 systematic reviews from November 2020 served as a comparator. RESULTS: We identified 246 systematic reviews on COVID-19. In the abstract of these reviews, just over half (57%) reported the search date (day/month/year or month/year) while 43% failed to report any date. When the full text was considered, the search date was missing from 6% of reviews. The median time from last search to publication online was 91 days (IQR 63-130). Time from search to publication was similar for the subset of 15 rapid or living reviews (92 days) but shorter for the 29 reviews published as preprints (37 days). The median number of studies or publications included per review was 23 (IQR 12-40). In the sample of 290 non-COVID SRs, around two-thirds (65%) reported the search date while a third (34%) did not include any date in the abstract. The median time from search to publication online was 253 days (IQR 153-381) and each review included a median of 12 studies (IQR 8-21). CONCLUSIONS: Despite the context of the pandemic and the need to easily ascertain the currency of systematic reviews, reporting of the search date information for COVID-19 reviews was inadequate. Adherence to reporting guidelines would improve the transparency and usefulness of systematic reviews to users.

Weekly updating of guideline recommendations was feasible: the Australian National COVID-19 clinical evidence Taskforce.

OBJECTIVES: To investigate how quickly evidence was incorporated into the Australian living guidelines for COVID-19 during the first 12 months of the pandemic. STUDY DESIGN AND SETTING: For each study concerning drug therapies included in the guideline from April 3, 2020 to April 1, 2021, we extracted the publication date of the study, and the guideline version the study was included in. We analyzed two subgroups of studies as follows: those published in high impact factor journals and those with 100 or more participants. RESULTS: In the first year, we published 37 major versions of the guidelines, incorporating 129 studies that investigated 48 drug therapies informing 115 recommendations. The median time from first publication of a study to incorporation in the guideline was 27 days (interquartile range [IQR], 16 to 44), ranging from 9 to 234 days. For the 53 studies in the highest impact factor journals, the median was 20 days (IQR 15 to 30), and for the 71 studies with 100 or more participants the median was 22 days (IQR 15 to 36). CONCLUSION: Developing and sustaining living guidelines where evidence is rapidly incorporated is a resource- and time-intensive undertaking; however, this study demonstrates that it is feasible, even over a long period.

Methods for living guidelines: early guidance based on practical experience. Paper 5: decisions on methods for evidence synthesis and recommendation development for living guidelines.

OBJECTIVES: Producing living guidelines requires making important decisions about methods for evidence identification, appraisal, and integration to allow the living mode to function. Clarifying what these decisions are and the trade-offs between options is necessary. This article provides living guideline developers with a framework to enable them to choose the most suitable model for their living guideline topic, question, or context. STUDY DESIGN AND SETTING: We developed this guidance through an iterative process informed by interviews, feedback, and a consensus process with an international group of living guideline developers. RESULTS: Several key decisions need to be made both before commencing and throughout the continual process of living guideline development and maintenance. These include deciding what approach is taken to the systematic review process; decisions about methods to be applied for the evidence appraisal process, including the use of unpublished data; and selection of "triggers" to incorporate new studies into living guideline recommendations. In each case, there are multiple options and trade-offs. CONCLUSION: We identify trade-offs and important decisions to be considered throughout the living guideline development process. The most appropriate, and most sustainable, mode of development and updating will be dependent on the choices made in each of these areas.

Methods for living guidelines: early guidance based on practical experience. Paper 3: selecting and prioritizing questions for living guidelines.

OBJECTIVES: This article is part of a series on methods for living guidelines, consolidating practical experiences from developing living guidelines. It focuses on methods for identification, selection, and prioritization of clinical questions for a living approach to guideline development. STUDY DESIGN AND SETTING: Members of the Australian Living Evidence Consortium, the National Institute of Health and Care Excellence and the US Grading of Recommendations, Assessment, Development and Evaluations Network, convened a working group. All members have expertize and practical experience in the development of living guidelines. We collated methods, documents on prioritization from each organization's living guidelines, conducted interviews and held working group discussions. We consolidated these to form best practice principles which were then edited and agreed on by the working group members. RESULTS: We developed best practice principles for (1) identification, (2) selection, and (3) prioritization, of questions for a living approach to guideline development. Several different strategies for undertaking prioritizing questions are explored. CONCLUSION: The article provides guidance for prioritizing questions in living guidelines. Subsequent articles in this series explore consumer involvement, search decisions, and methods decisions that are appropriate for questions with different priority levels.

Methods for living guidelines: early guidance based on practical experience. Paper 2: consumer engagement in living guidelines.

OBJECTIVES: To describe and reflect on the consumer engagement approaches used in five living guidelines from the perspectives of consumers (i.e., patients, carers, the public, and their representatives) and guideline developers. STUDY DESIGN AND SETTING: In a descriptive report, we used a template to capture engagement approaches and the experiences of consumers and guideline developers in living guidelines in Australia and the United Kingdom. Responses were summarized using descriptive synthesis. RESULTS: One guideline used a Consumer Panel, three included two to three consumers in the guideline development group, and one did both. Much of our experience was common to all guidelines (e.g., consumers felt welcomed but that their role initially lacked clarity). We identified six challenges and opportunities specific to living guidelines: managing the flow of work; managing engagement in online environments; managing membership of the panel; facilitating more flexibility, variety and depth in engagement; recruiting for specific skills-although these can be built over time; developing living processes to improve; and adapting consumer engagement together. CONCLUSION: Consumer engagement in living guidelines should follow established principles of consumer engagement in guidelines. Conceiving the engagement as living, underpinned by a living process evaluation, allows the approach to be developed with consumers over time.

Methods for living guidelines: early guidance based on practical experience. Paper 1: Introduction.

OBJECTIVES: To introduce methods for living guidelines based on practical experiences by the Australian Living Evidence Consortium (ALEC), the National Institute of Health and Care Excellence (NICE), and the Infectious Diseases Society of America (IDSA), with methodological support from the US Grading of Recommendations, Assessment, Development and Evaluations (GRADE) Network. STUDY DESIGN AND SETTING: Members of ALEC, NICE, and the US GRADE Network, convened a working group to share experiences of the methods used to develop living guidelines and outline the key differences between traditional and living guidelines methods. RESULTS: The guidance includes the following steps: 1) deciding if the guideline is a priority for a living approach, 2) preparing for living guideline development, 3) literature surveillance and frequency of searching, 4) assessment and synthesis of the evidence, 5) publication and dissemination, and 6) transitioning recommendations out of living mode. CONCLUSION: This paper introduces methods for living guidelines and provides examples of the similarities and differences in approach across multiple organizations conducting living guidelines. It also introduces a series of papers exploring methods for living guidelines based on our practical experiences, including consumer involvement, selecting and prioritizing questions, search decisions, and methods decisions.

Electronic cigarettes for smoking cessation.

BACKGROUND: Electronic cigarettes (ECs) are handheld electronic vaping devices which produce an aerosol by heating an e-liquid. Some people who smoke use ECs to stop or reduce smoking, although some organizations, advocacy groups and policymakers have discouraged this, citing lack of evidence of efficacy and safety. People who smoke, healthcare providers and regulators want to know if ECs can help people quit smoking, and if they are safe to use for this purpose. This is a review update conducted as part of a living systematic review. OBJECTIVES: To examine the effectiveness, tolerability, and safety of using electronic cigarettes (ECs) to help people who smoke tobacco achieve long-term smoking abstinence. SEARCH METHODS: We searched the Cochrane Tobacco Addiction Group's Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and PsycINFO to 1 July 2022, and reference-checked and contacted study authors.  SELECTION CRITERIA: We included randomized controlled trials (RCTs) and randomized cross-over trials, in which people who smoke were randomized to an EC or control condition. We also included uncontrolled intervention studies in which all participants received an EC intervention. Studies had to report abstinence from cigarettes at six months or longer or data on safety markers at one week or longer, or both. DATA COLLECTION AND ANALYSIS: We followed standard Cochrane methods for screening and data extraction. Our primary outcome measures were abstinence from smoking after at least six months follow-up, adverse events (AEs), and serious adverse events (SAEs). Secondary outcomes included the proportion of people still using study product (EC or pharmacotherapy) at six or more months after randomization or starting EC use, changes in carbon monoxide (CO), blood pressure (BP), heart rate, arterial oxygen saturation, lung function, and levels of carcinogens or toxicants, or both. We used a fixed-effect Mantel-Haenszel model to calculate risk ratios (RRs) with a 95% confidence interval (CI) for dichotomous outcomes. For continuous outcomes, we calculated mean differences. Where appropriate, we pooled data in meta-analyses. MAIN RESULTS: We included 78 completed studies, representing 22,052 participants, of which 40 were RCTs. Seventeen of the 78 included studies were new to this review update. Of the included studies, we rated ten (all but one contributing to our main comparisons) at low risk of bias overall, 50 at high risk overall (including all non-randomized studies), and the remainder at unclear risk. There was high certainty that quit rates were higher in people randomized to nicotine EC than in those randomized to nicotine replacement therapy (NRT) (RR 1.63, 95% CI 1.30 to 2.04; I2 = 10%; 6 studies, 2378 participants). In absolute terms, this might translate to an additional four quitters per 100 (95% CI 2 to 6). There was moderate-certainty evidence (limited by imprecision) that the rate of occurrence of AEs was similar between groups (RR 1.02, 95% CI 0.88 to 1.19; I2 = 0%; 4 studies, 1702 participants). SAEs were rare, but there was insufficient evidence to determine whether rates differed between groups due to very serious imprecision (RR 1.12, 95% CI 0.82 to 1.52; I2 = 34%; 5 studies, 2411 participants). There was moderate-certainty evidence, limited by imprecision, that quit rates were higher in people randomized to nicotine EC than to non-nicotine EC (RR 1.94, 95% CI 1.21 to 3.13; I2 = 0%; 5 studies, 1447 participants). In absolute terms, this might lead to an additional seven quitters per 100 (95% CI 2 to 16). There was moderate-certainty evidence of no difference in the rate of AEs between these groups (RR 1.01, 95% CI 0.91 to 1.11; I2 = 0%; 5 studies, 1840 participants). There was insufficient evidence to determine whether rates of SAEs differed between groups, due to very serious imprecision (RR 1.00, 95% CI 0.56 to 1.79; I2 = 0%; 8 studies, 1272 participants). Compared to behavioural support only/no support, quit rates were higher for participants randomized to nicotine EC (RR 2.66, 95% CI 1.52 to 4.65; I2 = 0%; 7 studies, 3126 participants). In absolute terms, this represents an additional two quitters per 100 (95% CI 1 to 3). However, this finding was of very low certainty, due to issues with imprecision and risk of bias. There was some evidence that (non-serious) AEs were more common in people randomized to nicotine EC (RR 1.22, 95% CI 1.12 to 1.32; I2 = 41%, low certainty; 4 studies, 765 participants) and, again, insufficient evidence to determine whether rates of SAEs differed between groups (RR 1.03, 95% CI 0.54 to 1.97; I2 = 38%; 9 studies, 1993 participants).  Data from non-randomized studies were consistent with RCT data. The most commonly reported AEs were throat/mouth irritation, headache, cough, and nausea, which tended to dissipate with continued EC use. Very few studies reported data on other outcomes or comparisons, hence evidence for these is limited, with CIs often encompassing clinically significant harm and benefit. AUTHORS' CONCLUSIONS: There is high-certainty evidence that ECs with nicotine increase quit rates compared to NRT and moderate-certainty evidence that they increase quit rates compared to ECs without nicotine. Evidence comparing nicotine EC with usual care/no treatment also suggests benefit, but is less certain. More studies are needed to confirm the effect size. Confidence intervals were for the most part wide for data on AEs, SAEs and other safety markers, with no difference in AEs between nicotine and non-nicotine ECs nor between nicotine ECs and NRT. Overall incidence of SAEs was low across all study arms. We did not detect evidence of serious harm from nicotine EC, but longest follow-up was two years and the number of studies was small. The main limitation of the evidence base remains imprecision due to the small number of RCTs, often with low event rates, but further RCTs are underway. To ensure the review continues to provide up-to-date information to decision-makers, this review is a living systematic review. We run searches monthly, with the review updated when relevant new evidence becomes available. Please refer to the Cochrane Database of Systematic Reviews for the review's current status.