Benefits and harms of direct oral anticoagulation and low molecular weight heparin for thromboprophylaxis in patients undergoing non-cardiac surgery: systematic review and network meta-analysis of randomised trials.

OBJECTIVE: To systematically compare the effect of direct oral anticoagulants and low molecular weight heparin for thromboprophylaxis on the benefits and harms to patients undergoing non-cardiac surgery. DESIGN: Systematic review and network meta-analysis of randomised controlled trials. DATA SOURCES: Medline, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL), up to August 2021. REVIEW METHODS: Randomised controlled trials in adults undergoing non-cardiac surgery were selected, comparing low molecular weight heparin (prophylactic (low) or higher dose) with direct oral anticoagulants or with no active treatment. Main outcomes were symptomatic venous thromboembolism, symptomatic pulmonary embolism, and major bleeding. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used for network meta-analyses. Abstracts and full texts were screened independently in duplicate. Data were abstracted on study participants, interventions, and outcomes, and risk of bias was assessed independently in duplicate. Frequentist network meta-analysis with multivariate random effects models provided odds ratios with 95% confidence intervals, and GRADE (grading of recommendations, assessment, development, and evaluation) assessments indicated the certainty of the evidence. RESULTS: 68 randomised controlled trials were included (51 orthopaedic, 10 general, four gynaecological, two thoracic, and one urological surgery), involving 45 445 patients. Low dose (odds ratio 0.33, 95% confidence interval 0.16 to 0.67) and high dose (0.19, 0.07 to 0.54) low molecular weight heparin, and direct oral anticoagulants (0.17, 0.07 to 0.41) reduced symptomatic venous thromboembolism compared with no active treatment, with absolute risk differences of 1-100 per 1000 patients, depending on baseline risks (certainty of evidence, moderate to high). None of the active agents reduced symptomatic pulmonary embolism (certainty of evidence, low to moderate). Direct oral anticoagulants and low molecular weight heparin were associated with a 2-3-fold increase in the odds of major bleeding compared with no active treatment (certainty of evidence, moderate to high), with absolute risk differences as high as 50 per 1000 in patients at high risk. Compared with low dose low molecular weight heparin, high dose low molecular weight heparin did not reduce symptomatic venous thromboembolism (0.57, 0.26 to 1.27) but increased major bleeding (1.87, 1.06 to 3.31); direct oral anticoagulants reduced symptomatic venous thromboembolism (0.53, 0.32 to 0.89) and did not increase major bleeding (1.23, 0.89 to 1.69). CONCLUSIONS: Direct oral anticoagulants and low molecular weight heparin reduced venous thromboembolism compared with no active treatment but probably increased major bleeding to a similar extent. Direct oral anticoagulants probably prevent symptomatic venous thromboembolism to a greater extent than prophylactic low molecular weight heparin. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42018106181.

Consideration of antimicrobial resistance and contextual factors in infectious disease guidelines: a systematic survey.

OBJECTIVES: Guidelines that include antimicrobial recommendations should explicitly consider contextual factors that influence antimicrobial resistance and their downstream effects on resistance selection. The objectives were to analyse (1) how, and to what extent, tuberculosis, gonorrhoea and respiratory tract infection guidelines are considering antimicrobial resistance; (2) are of acceptable quality and (3) if they can be easily contextualised to fit the needs of specific populations and health systems. METHODS: We conducted a systematic review and searched Ovid MEDLINE and Embase from 1 January 2007 to 7 June 2019 for tuberculosis, gonorrhoea and respiratory tract infection guidelines published in English. We also searched guideline databases, key websites and reference lists. We identified guidelines and recommendations that considered contextual factors including antimicrobial resistance, values, resource use, equity, acceptability and feasibility. We assessed quality of the guidelines using the Appraisal of Guidelines for Research and Evaluation II tool focusing on the domains scope and purpose, rigour of development, and editorial independence. RESULTS: We screened 10 365 records, of which 74 guidelines met inclusion criteria. Of these guidelines, 39% (n=29/74) met acceptable quality scores. Approximately two-thirds of recommendations considered antimicrobial resistance at the population and/or outcome level. Five of the 29 guidelines reported all factors required for recommendation contextualisation. Equity was the least considered across guidelines. DISCUSSION: Relatively few guidelines for highly prevalent infectious diseases are considering resistance at a local level, and many do not consider contextual factors necessary for appropriate antimicrobial use. Improving the quality of guidelines targeting specific regional areas is required. PROSPERO REGISTRATION NUMBER: CRD42020145235.

American Society of Hematology 2021 guidelines on the use of anticoagulation for thromboprophylaxis in patients with COVID-19.

BACKGROUND: Coronavirus disease 2019 (COVID-19)-related critical illness and acute illness are associated with a risk of venous thromboembolism (VTE). OBJECTIVE: These evidence-based guidelines of the American Society of Hematology (ASH) are intended to support patients, clinicians, and other health care professionals in decisions about the use of anticoagulation for thromboprophylaxis for patients with COVID-19-related critical illness and acute illness who do not have confirmed or suspected VTE. METHODS: ASH formed a multidisciplinary guideline panel and applied strict management strategies to minimize potential bias from conflicts of interest. The panel included 3 patient representatives. The McMaster University GRADE Centre supported the guideline-development process, including performing systematic evidence reviews (up to 19 August 2020). The panel prioritized clinical questions and outcomes according to their importance for clinicians and patients. The panel used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach, including GRADE Evidence-to-Decision frameworks, to assess evidence and make recommendations, which were subject to public comment. RESULTS: The panel agreed on 2 recommendations. The panel issued conditional recommendations in favor of prophylactic-intensity anticoagulation over intermediate-intensity or therapeutic-intensity anticoagulation for patients with COVID-19-related critical illness or acute illness who do not have confirmed or suspected VTE. CONCLUSIONS: These recommendations were based on very low certainty in the evidence, underscoring the need for high-quality, randomized controlled trials comparing different intensities of anticoagulation. They will be updated using a living recommendation approach as new evidence becomes available.

Assessing the process and outcome of the development of practice guidelines and recommendations: PANELVIEW instrument development.

BACKGROUND: Guideline recommendations may be affected by flaws in the process, inappropriate panel member selection or conduct, conflicts of interest and other factors. To our knowledge, no validated tool exists to evaluate guideline development from the perspective of those directly involved in the process. Our objective was to develop and validate a universal tool, the PANELVIEW instrument, to assess guideline processes, methods and outcomes from the perspective of the participating guideline panellists and group members. METHODS: We performed a systematic literature search and surveys of guideline groups (identified through contacting international organizations and convenience sampling of working panels) to inform item generation. Subsequent groups of guideline methodologists and panellists reviewed items for face validity and missing items. We used surveys, interviews and expert review for item reduction and phrasing. For reliability assessment and feedback, we tested the PANELVIEW tool in 8 international guideline groups. RESULTS: We surveyed 62 members from 13 guideline panels, contacted 19 organizations and reviewed 20 source documents to generate items. Fifty-three additional key informants provided feedback about phrasing of the items and response options. We reduced the number of items from 95 to 34 across domains that included administration, training, conflict of interest, group dynamics, chairing, evidence synthesis, formulating recommendations and publication. The tool takes about 10 minutes to complete and showed acceptable measurement properties. INTERPRETATION: The PANELVIEW instrument fills a gap by enabling guideline organizations to involve clinicians, patients and other participants in evaluating their guideline processes. The tool can inform quality improvement of existing or new guideline programs, focusing on insight into and transparency of the guideline development process, methods and outcomes.

Evaluating prophylactic heparin in ambulatory patients with solid tumours: a systematic review and individual participant data meta-analysis.

BACKGROUND: Study-level meta-analyses provide high-certainty evidence that heparin reduces the risk of symptomatic venous thromboembolism for patients with cancer; however, whether the benefits and harms associated with heparin differ by cancer type is unclear. This individual participant data meta-analysis of randomised controlled trials examines the effect of heparin on survival, venous thromboembolism, and bleeding in patients with cancer in general and by type. METHODS: In this systematic review and meta-analysis we searched MEDLINE, Embase, and The Cochrane Library for randomised controlled trials comparing parenteral anticoagulants with placebo or standard care in ambulatory patients with solid tumours and no indication for anticoagulation published from the inception of each database to January 14, 2017, and updated it on May 14, 2020, without language restrictions. We calculated the effect of parenteral anticoagulant administration on all-cause mortality, venous thromboembolism occurrence, and bleeding related outcomes through multivariable hierarchical models with patient-level variables as fixed effects and a categorical trial variable as a random effect, adjusting for age, cancer type, and metastatic status. Interaction terms were tested to investigate effects in predefined subgroups. This study is registered with PROSPERO, CRD42013003526. FINDINGS: We obtained individual participant data from 14 of 20 eligible randomised controlled trials (8278 [79%] of 10 431 participants; 4139 included in the low-molecular-weight heparin group and 4139 in the control group). Meta-analysis showed an adjusted relative risk (RR) of mortality at 1 year of 0·99 (95% CI 0·93-1·06) and a hazard ratio of 1·01 (95% CI 0·96-1·07). The number of patients with venous thromboembolic events was 158 (4·0%) of 3958 with available data in the low-molecular-weight heparin group compared with 279 (7·1%) of 3957 in the control group. Major bleeding events occurred in 71 (1·7%) of 4139 patients in the control population and 88 (2·1%) in the low-molecular-weight heparin group, and minor bleeding events in 478 (12·1%) of 3945 patients with available data in the control group and 652 (16·6%) of 3937 patients in the low-molecular-weight heparin group. The adjusted RR was 0·58 (95% CI 0·47-0·71) for venous thromboembolism, 1·27 (0·92-1·74) for major bleeding, and 1·34 (1·19-1·51) for minor bleeding. Prespecified subgroup analysis of venous thromboembolism occurrence by cancer type identified the most certain benefit from heparin treatment in patients with lung cancer (RR 0·59 [95% CI 0·42-0·81]), which dominated the overall reduction in venous thromboembolism. Certainty of the evidence for the outcomes ranged from moderate to high. INTERPRETATION: Low-molecular-weight heparin reduces risk of venous thromboembolism without increasing risk of major bleeding compared with placebo or standard care in patients with solid tumours, but it does not improve survival. FUNDING: Canadian Institutes of Health Research.

Pharmacologic thromboprophylaxis in adult patients undergoing neurosurgical interventions for preventing venous thromboembolism.

The impact of pharmacologic prophylaxis for venous thromboembolism in patients undergoing neurosurgical intervention remains uncertain. We reviewed the efficacy and safety of pharmacologic compared with nonpharmacologic thromboprophylaxis in neurosurgical patients. Three databases were searched through April 2018, including those for randomized controlled trials (RCTs) and for nonrandomized controlled studies (NRSs). Independent reviewers assessed the certainty of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Seven RCTs and 3 NRSs proved eligible. No studies reported on symptomatic proximal and distal deep vein thrombosis (DVT). Two RCTs reported on screening-detected proximal and distal DVTs. We used the findings of these 2 RCTs as the closest surrogate outcomes to inform the proximal and distal DVT outcomes. These 2 RCTs suggest that pharmacologic thromboprophylaxis may decrease the risk of developing asymptomatic proximal DVT (relative risk [RR], 0.50; 95% confidence interval [CI], 0.30-0.84; low certainty). Findings were uncertain for mortality (RR, 1.27; 95% CI, 0.57-2.86; low certainty), symptomatic pulmonary embolism (PE) (RR, 0.84; 95% CI, 0.03-27.42; very low certainty), asymptomatic distal DVT (RR, 0.54; 95% CI, 0.27-1.08; very low certainty), and reoperation (RR, 0.43; 95% CI, 0.06-2.84; very low certainty) outcomes. NRSs also reported uncertain findings for whether pharmacologic prophylaxis affects mortality (RR, 0.72; 95% CI, 0.46-1.13; low certainty) and PE (RR, 0.18; 95% CI, 0.01-3.76). For risk of bleeding, findings were uncertain in both RCTs (RR, 1.57; 95% CI, 0.70-3.50; low certainty) and NRSs (RR, 1.45; 95% CI, 0.30-7.12; very low certainty). In patients undergoing neurosurgical procedures, low certainty of evidence suggests that pharmacologic thromboprophylaxis confers benefit for preventing asymptomatic (screening-detected) proximal DVT with very low certainty regarding its impact on patient-important outcomes.

Obtaining and managing data sets for individual participant data meta-analysis: scoping review and practical guide.

BACKGROUND: Shifts in data sharing policy have increased researchers' access to individual participant data (IPD) from clinical studies. Simultaneously the number of IPD meta-analyses (IPDMAs) is increasing. However, rates of data retrieval have not improved. Our goal was to describe the challenges of retrieving IPD for an IPDMA and provide practical guidance on obtaining and managing datasets based on a review of the literature and practical examples and observations. METHODS: We systematically searched MEDLINE, Embase, and the Cochrane Library, until January 2019, to identify publications focused on strategies to obtain IPD. In addition, we searched pharmaceutical websites and contacted industry organizations for supplemental information pertaining to recent advances in industry policy and practice. Finally, we documented setbacks and solutions encountered while completing a comprehensive IPDMA and drew on previous experiences related to seeking and using IPD. RESULTS: Our scoping review identified 16 articles directly relevant for the conduct of IPDMAs. We present short descriptions of these articles alongside overviews of IPD sharing policies and procedures of pharmaceutical companies which display certification of Principles for Responsible Clinical Trial Data Sharing via Pharmaceutical Research and Manufacturers of America or European Federation of Pharmaceutical Industries and Associations websites. Advances in data sharing policy and practice affected the way in which data is requested, obtained, stored and analyzed. For our IPDMA it took 6.5 years to collect and analyze relevant IPD and navigate additional administrative barriers. Delays in obtaining data were largely due to challenges in communication with study sponsors, frequent changes in data sharing policies of study sponsors, and the requirement for a diverse skillset related to research, administrative, statistical and legal issues. CONCLUSIONS: Knowledge of current data sharing practices and platforms as well as anticipation of necessary tasks and potential obstacles may reduce time and resources required for obtaining and managing data for an IPDMA. Sufficient project funding and timeline flexibility are pre-requisites for successful collection and analysis of IPD. IPDMA researchers must acknowledge the additional and unexpected responsibility they are placing on corresponding study authors or data sharing administrators and should offer assistance in readying data for sharing.

The Khorana score for prediction of venous thromboembolism in cancer patients: An individual patient data meta-analysis.

BACKGROUND: Oncology guidelines suggest using the Khorana score to select ambulatory cancer patients receiving chemotherapy for primary venous thromboembolism (VTE) prevention, but its performance in different cancers remains uncertain. OBJECTIVE: To examine the performance of the Khorana score in assessing 6-month VTE risk, and the efficacy and safety of low-molecular-weight heparin (LMWH) among high-risk Khorana score patients. METHODS: This individual patient data meta-analysis evaluated (ultra)-LMWH in patients with solid cancer using data from seven randomized controlled trials. RESULTS: A total of 3293 patients from the control groups with an available Khorana score had lung (n = 1913; 58%), colorectal (n = 452; 14%), pancreatic (n = 264; 8%), gastric (n = 201; 6%), ovarian (n = 184; 56%), breast (n = 164; 5%), brain (n = 84; 3%), or bladder cancer (n = 31; 1%). The 6-month VTE incidence was 9.8% among high-risk Khorana score patients and 6.4% among low-to-intermediate-risk patients (odds ratio [OR], 1.6; 95% confidence interval [CI], 1.1-2.2). The dichotomous Khorana score performed differently in lung cancer patients (OR 1.1; 95% CI, 0.72-1.7) than in the group with other cancer types (OR 3.2; 95% CI, 1.8-5.6; Pinteraction  = .002). Among high-risk patients, LMWH decreased the risk of VTE by 64% compared with controls (OR 0.36; 95% CI, 0.22-0.58), without increasing the risk of major bleeding (OR 1.1; 95% CI, 0.59-2.1). CONCLUSION: The Khorana score was unable to stratify patients with lung cancer based on their VTE risk. Among those with other cancer types, a high-risk score was associated with a three-fold increased risk of VTE compared with a low-to-intermediate risk score. Thromboprophylaxis was effective and safe in patients with a high-risk Khorana score.

A systematic review of how patients value COPD outcomes.

Our objective was to summarise systematically all research evidence related to how patients value outcomes in chronic obstructive pulmonary disease (COPD).We conducted a systematic review (systematic review registration number CRD42015015206) by searching PubMed, Embase, PsycInfo and CINAHL, and included reports that assessed the relative importance of outcomes from COPD patients' perspective. Two authors independently determined the eligibility of studies, abstracted the eligible studies and assessed risk of bias. We narratively summarised eligible studies, meta-analysed utilities for individual outcomes and assessed the certainty of evidence using the Grading of Recommendations, Assessment, Development and Evaluations approach.We included 217 quantitative studies. Investigators most commonly used utility measurements of outcomes (n=136), discrete choice exercises (n=13), probability trade-off (n=4) and forced choice techniques (n=46). Patients rated adverse events as important but on average, less so than symptom relief. Exacerbation and hospitalisation due to exacerbation are the outcomes that COPD patients rate as most important. This systematic review provides a comprehensive registry of related studies.

Decision making about healthcare-related tests and diagnostic test strategies. Paper 5: a qualitative study with experts suggests that test accuracy data alone is rarely sufficient for decision making.

OBJECTIVES: The objective of the study was to identify the critical factors that determine recommendations and other decisions about healthcare-related tests and diagnostic strategies (HCTDS). METHODS: We used a qualitative descriptive approach and conducted semi-structured in-depth interviews with 24 international experts (informants) in evidence and decisions about HCTDS. RESULTS: Although test accuracy (TA) was the factor most commonly considered by organizations when developing recommendations about HCTDS, informants agreed that TA is necessary but rarely, if ever, sufficient and may be misleading when solely considered. The informants identified factors that are important for developing recommendations about HCTDS. Informants largely agreed that laying out the potential care pathways based on the test result is an essential early step but is rarely done in developing recommendations about HCTDS. Most informants also agreed that decision analysis could be useful for organizing the clinical, cost, and preference data relevant to the use of tests in the absence of direct evidence. However, they noted that using models is limited by the lack of resources and expertise required. CONCLUSION: Developing guidelines about HCTDS requires consideration of factors beyond TA, but implementing this may be challenging. Further development and testing of "frameworks" that can guide this process is a priority for decision makers.

Decision making about healthcare-related tests and diagnostic test strategies. Paper 4: International guidelines show variability in their approaches.

OBJECTIVES: The objective of the study was to describe and compare current practices in developing guidelines about the use of healthcare-related tests and diagnostic strategies (HCTDS). STUDY DESIGN AND SETTING: We sampled 37 public health and clinical practice guidelines about HCTDS from various sources without language restrictions. RESULTS: Detailed descriptions of the systems used to assess the quality of evidence and develop recommendations were challenging to find within guidelines. We observed much variability among and within organizations with respect to how they develop recommendations about HCTDS. Twenty-four percent of the guidelines did not consider health benefits and harms but based decisions solely on test accuracy. We did not identify guidelines that described the main potential care pathways involving tests for a healthcare problem. In addition, we did not identify guidelines that systematically assessed, described, and referenced the evidence that linked test accuracy and patient-important outcomes. CONCLUSION: There is considerable variability among the processes used and factors considered in developing recommendations about the use of tests. This variability may be the cause for the disagreement we observed in recommendations about testing for the same condition.

Decision making about healthcare-related tests and diagnostic test strategies. Paper 3: a systematic review shows limitations in most tools designed to assess quality and develop recommendations.

OBJECTIVES: The objective of this study was to identify and describe critical appraisal tools designed for assessing the quality of evidence (QoE) and/or strength of recommendations (SoRs) related to health care-related tests and diagnostic strategies (HCTDSs). STUDY DESIGN AND SETTING: We conducted a systematic review to identify tools applied in guidelines, methodological articles, and systematic reviews to assess HCTDS. RESULTS: We screened 5,534 titles and abstracts, 1,004 full-text articles, and abstracted data from 330 references. We identified 29 tools and 14 modifications of existing tools for assessing QoE and SoR. Twenty-three out of 29 tools acknowledge the importance of assessing the QoE and SoR separately, but in 8, the SoR is based solely on QoE. When making decisions about the use of tests, patient values and preferences and impact on resource utilization were considered in 6 and 8 tools, respectively. There is also confusion about the terminology that describes the various factors that influence the QoE and SoR. CONCLUSION: Although at least one approach includes all relevant criteria for assessing QoE and determining SoR, more detailed guidance about how to operationalize these assessments and make related judgments will be beneficial. There is a need for a better description of the framework for using evidence to make decisions and develop recommendations about HCTDS.

Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines-2016 revision.

BACKGROUND: Allergic rhinitis (AR) affects 10% to 40% of the population. It reduces quality of life and school and work performance and is a frequent reason for office visits in general practice. Medical costs are large, but avoidable costs associated with lost work productivity are even larger than those incurred by asthma. New evidence has accumulated since the last revision of the Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines in 2010, prompting its update. OBJECTIVE: We sought to provide a targeted update of the ARIA guidelines. METHODS: The ARIA guideline panel identified new clinical questions and selected questions requiring an update. We performed systematic reviews of health effects and the evidence about patients' values and preferences and resource requirements (up to June 2016). We followed the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) evidence-to-decision frameworks to develop recommendations. RESULTS: The 2016 revision of the ARIA guidelines provides both updated and new recommendations about the pharmacologic treatment of AR. Specifically, it addresses the relative merits of using oral H1-antihistamines, intranasal H1-antihistamines, intranasal corticosteroids, and leukotriene receptor antagonists either alone or in combination. The ARIA guideline panel provides specific recommendations for the choice of treatment and the rationale for the choice and discusses specific considerations that clinicians and patients might want to review to choose the management most appropriate for an individual patient. CONCLUSIONS: Appropriate treatment of AR might improve patients' quality of life and school and work productivity. ARIA recommendations support patients, their caregivers, and health care providers in choosing the optimal treatment.

Use of heparins in patients with cancer: individual participant data meta-analysis of randomised trials study protocol.

INTRODUCTION: Parenteral anticoagulants may improve outcomes in patients with cancer by reducing risk of venous thromboembolic disease and through a direct antitumour effect. Study-level systematic reviews indicate a reduction in venous thromboembolism and provide moderate confidence that a small survival benefit exists. It remains unclear if any patient subgroups experience potential benefits. METHODS AND ANALYSIS: First, we will perform a comprehensive systematic search of MEDLINE, EMBASE and The Cochrane Library, hand search scientific conference abstracts and check clinical trials registries for randomised control trials of participants with solid cancers who are administered parenteral anticoagulants. We anticipate identifying at least 15 trials, exceeding 9000 participants. Second, we will perform an individual participant data meta-analysis to explore the magnitude of survival benefit and address whether subgroups of patients are more likely to benefit from parenteral anticoagulants. All analyses will follow the intention-to-treat principle. For our primary outcome, mortality, we will use multivariable hierarchical models with patient-level variables as fixed effects and a categorical trial variable as a random effect. We will adjust analysis for important prognostic characteristics. To investigate whether intervention effects vary by predefined subgroups of patients, we will test interaction terms in the statistical model. Furthermore, we will develop a risk-prediction model for venous thromboembolism, with a focus on control patients of randomised trials. ETHICS AND DISSEMINATION: Aside from maintaining participant anonymity, there are no major ethical concerns. This will be the first individual participant data meta-analysis addressing heparin use among patients with cancer and will directly influence recommendations in clinical practice guidelines. Major cancer guideline development organisations will use eventual results to inform their guideline recommendations. Several knowledge users will disseminate results through presentations at clinical rounds as well as national and international conferences. We will prepare an evidence brief and facilitate dialogue to engage policymakers and stakeholders in acting on findings. TRIAL REGISTRATION NUMBER: PROSPERO CRD42013003526.

Improving GRADE evidence tables part 2: a systematic survey of explanatory notes shows more guidance is needed.

OBJECTIVES: The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) working group has developed GRADE evidence profiles (EP) and summary of findings (SoF) tables to present evidence summaries in systematic reviews, clinical guidelines, and health technology assessments. Explanatory notes are used to explain choices and judgments in these summaries, for example, on rating of the quality of evidence. STUDY DESIGN AND SETTING: A systematic survey of the explanations in SoF tables in 132 randomly selected Cochrane Intervention reviews and in EPs of 10 guidelines. We analyzed the content of 1,291 explanations using a predefined list of criteria. RESULTS: Most explanations were used to describe or communicate results and to explain downgrading of the quality of evidence, in particular for risk of bias and imprecision. Addressing the source of baseline risk (observational data or control group risk) was often missing. For judgments about downgrading the quality of evidence, the percentage of informative explanations ranged between 41% (imprecision) and 79% (indirectness). CONCLUSION: We found that by and large explanations were informative but detected several areas for improvement (e.g., source of baseline risk and judgments on imprecision). Guidance about explanatory footnotes and comments will be provided in the last article in this series.

Systematic review of observational studies assessing bleeding risk in patients with atrial fibrillation not using anticoagulants.

BACKGROUND: Patients with atrial fibrillation considering use of anticoagulants must balance stroke reduction against bleeding risk. Knowledge of bleeding risk without the use of anticoagulants may help inform this decision. PURPOSE: To determine the rate of major bleeding reported in observational studies of atrial fibrillation patients not receiving Vitamin K antagonists (VKA). DATA SOURCES: We searched MEDLINE, EMBASE and CINAHL to October 2011 and examined reference lists of eligible studies and related reviews. STUDY SELECTION: All longitudinal cohort studies that included over 100 adult patients with atrial fibrillation not receiving VKA. DATA EXTRACTION: Teams of two reviewers independently and in duplicate adjudicated eligibility, assessed risk of bias and abstracted study characteristics and outcomes. DATA SYNTHESIS: Twenty-one eligible studies included 96,448 patients. Major bleeding rates varied widely, from 0 to 4.69 events per 100 patient-years. The pooled estimate in 13 studies with 78839 patients was 1.59 with a 99% confidence interval of 1.10 to 2.3 and median 1.42 (interquartile range 0.62-2.70). Pooled estimates for fatal bleeding and non-fatal bleeding from 4 studies that reported these outcomes were, respectively, 0.40 (0.34 to 0.46) and 1.18 (0.30 to 4.56) per 100 patient-years. In 9 randomized controlled trials (RCTs) the median rate of major bleeding in patients not receiving either anticoagulant or antiplatelet therapy was 0.6 (interquartile 0.2 to 0.90), and in 12 RCTs the median rate of major bleeding in patients receiving a single antiplatelet agent was 0.75 (interquartile 0.4 to 1.4). CONCLUSION: Results suggest that patients with atrial fibrillation not receiving VKA enrolled in observational studies represent a population on average at higher risk of bleeding.

A review of patient-reported outcomes for children and adolescents with obesity.

INTRODUCTION: Obesity is a chronic condition that can impact the physical, emotional, mental and social elements that encompass a child's life. The objectives of this study were to identify which generic and obesity-specific patient-reported outcome (PRO) instruments are used in obesity literature, as well as review their conceptual approach, health and health-related content, ethical content and psychometric properties. METHOD: PubMed, CINAHL, EMBASE and PsycINFO were searched from the inception of each database to May 2012 to identify all studies using multi-dimensional PRO instruments with children who are overweight or obese. The most common generic and all obesity-specific instruments were analyzed according to the study objectives. RESULTS: From 4,226 articles identified by our search, 70 articles used 6 generic and 4 obesity-specific PRO instruments. While the most commonly used PRO instrument was the generic PedsQL 4.0 (used in 53 studies), many health domains were found in the obesity-specific instruments that are not measured by the PedsQL 4.0. Summary of the development and psychometric properties of the generic and obesity PROs identified that no one instrument meets all the guideline criteria for instrument development and validation, e.g., only one instrument included qualitative input from children with obesity in the content development phase. DISCUSSION: This comprehensive review provides information to aid in selecting multi-dimensional PRO instruments in children with obesity according to various aspects of content as well as psychometric properties. The conceptual analysis shows that the reviewed PRO instruments contain inconsistencies in their conceptual approaches. Also, certain relevant health domains to children and youth with obesity were not included in the most commonly used generic instrument. The obesity-specific instruments require further validation before they can be used in intervention studies.

Guidelines 2.0: systematic development of a comprehensive checklist for a successful guideline enterprise.

BACKGROUND: Although several tools to evaluate the credibility of health care guidelines exist, guidance on practical steps for developing guidelines is lacking. We systematically compiled a comprehensive checklist of items linked to relevant resources and tools that guideline developers could consider, without the expectation that every guideline would address each item. METHODS: We searched data sources, including manuals of international guideline developers, literature on guidelines for guidelines (with a focus on methodology reports from international and national agencies, and professional societies) and recent articles providing systematic guidance. We reviewed these sources in duplicate, extracted items for the checklist using a sensitive approach and developed overarching topics relevant to guidelines. In an iterative process, we reviewed items for duplication and omissions and involved experts in guideline development for revisions and suggestions for items to be added. RESULTS: We developed a checklist with 18 topics and 146 items and a webpage to facilitate its use by guideline developers. The topics and included items cover all stages of the guideline enterprise, from the planning and formulation of guidelines, to their implementation and evaluation. The final checklist includes links to training materials as well as resources with suggested methodology for applying the items. INTERPRETATION: The checklist will serve as a resource for guideline developers. Consideration of items on the checklist will support the development, implementation and evaluation of guidelines. We will use crowdsourcing to revise the checklist and keep it up to date.