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Concept: Critical appraisal


Patients may be offered cardiac rehabilitation (CR), a supervised programme often including exercises, education and psychological care, following a cardiac event, with the aim of reducing morbidity and mortality. Cost-constrained healthcare systems require information about the best use of budget and resources to maximise patient benefit. We aimed to systematically review and critically appraise economic studies of CR and its components. In January 2016, validated electronic searches of the National Health Service Economic Evaluation Database (NHS EED), Health Technology Assessment, PsycINFO, MEDLINE and Embase databases were run to identify full economic evaluations published since 2001. Two levels of screening were used and explicit inclusion criteria were applied. Prespecified data extraction and critical appraisal were performed using the NHS EED handbook and Drummond checklist. The majority of studies concluded that CR was cost-effective versus no CR (incremental cost-effectiveness ratios (ICERs) ranged from $1065 to $71 755 per quality-adjusted life-year (QALY)). Evidence for specific interventions within CR was varied; psychological intervention ranged from dominant (cost saving and more effective) to $226 128 per QALY, telehealth ranged from dominant to $588 734 per QALY and while exercise was cost-effective across all relevant studies, results were subject to uncertainty. Key drivers of cost-effectiveness were risk of subsequent events and hospitalisation, hospitalisation and intervention costs, and utilities. This systematic review of studies evaluates the cost-effectiveness of CR in the modern era, providing a fresh evidence base for policy-makers. Evidence suggests that CR is cost-effective, especially with exercise as a component. However, research is needed to determine the most cost-effective design of CR.

Concepts: Health economics, Costs, Evidence-based medicine, Systematic review, Cost-utility analysis, Healthcare quality, Cost-Effectiveness Analysis Registry, Critical appraisal


A diverse, cross-sectorial group of partners, stakeholders and researchers, collaborated to develop an evidence-informed Position Statement on active outdoor play for children aged 3-12 years. The Position Statement was created in response to practitioner, academic, legal, insurance and public debate, dialogue and disagreement on the relative benefits and harms of active (including risky) outdoor play. The Position Statement development process was informed by two systematic reviews, a critical appraisal of the current literature and existing position statements, engagement of research experts (N = 9) and cross-sectorial individuals/organizations (N = 17), and an extensive stakeholder consultation process (N = 1908). More than 95% of the stakeholders consulted strongly agreed or somewhat agreed with the Position Statement; 14/17 participating individuals/organizations endorsed it; and over 1000 additional individuals and organizations requested their name be listed as a supporter. The final Position Statement on Active Outdoor Play states: “Access to active play in nature and outdoors-with its risks- is essential for healthy child development. We recommend increasing children’s opportunities for self-directed play outdoors in all settings-at home, at school, in child care, the community and nature.” The full Position Statement provides context for the statement, evidence supporting it, and a series of recommendations to increase active outdoor play opportunities to promote healthy child development.

Concepts: Evidence-based medicine, Systematic review, Childhood, Developmental psychology, Child development, Process, Critical appraisal, Critical period


Although a robust literature describes the intergenerational effects of traumatic experiences in various populations, evidence specific to refugee families is scattered and contains wide variations in approaches for examining intergenerational trauma. Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria, the purpose of this systematic review was to describe the methodologies and findings of peer-reviewed literature regarding intergenerational trauma in refugee families. In doing so we aimed to critically examine how existing literature characterizes refugee trauma, its long-term effects on descendants, and psychosocial processes of transmission in order to provide recommendations for future research. The results highlight populations upon which current evidence is based, conceptualizations of refugee trauma, effects of parental trauma transmission on descendants' health and well-being, and mechanisms of transmission and underlying meanings attributed to parental trauma in refugee families. Greater methodological rigor and consistency in future evidence-based research is needed to inform supportive systems that promote the health and well-being of refugees and their descendants.

Concepts: Scientific method, Critical thinking, Evidence-based medicine, Systematic review, Randomized controlled trial, Psychological trauma, Meta-analysis, Critical appraisal


Objective: Evidence on the effectiveness of walking and cycling interventions is mixed. This may be partly attributable to differences in intervention content, such as the cognitive and behavioral techniques (BCTs) used. Adopting a taxonomy of BCTs, this systematic review addressed two questions: (a) What are the behavior change techniques used in walking and cycling interventions targeted at adults? (b) What characterizes interventions that appear to be associated with changes in walking and cycling in adults? Method: Previous systematic reviews and updated database searches were used to identify controlled studies of individual-level walking and cycling interventions involving adults. Characteristics of intervention design, context, and methods were extracted in addition to outcomes. Intervention content was independently coded according to a 26-item taxonomy of BCTs. Results: Studies of 46 interventions met the inclusion criteria. Twenty-one reported a statistically significant effect on walking and cycling outcomes. Analysis revealed substantial heterogeneity in the vocabulary used to describe intervention content and the number of BCTs coded. “Prompt self-monitoring of behavior” and “prompt intention formation” were the most frequently coded BCTs. Conclusion: Future walking and cycling intervention studies should ensure that all aspects of the intervention are reported in detail. The findings lend support to the inclusion of self-monitoring and intention formation techniques in future walking and cycling intervention design, although further exploration of these and other BCTs is required. Further investigation of the interaction between BCTs and study design characteristics would also be desirable. (PsycINFO Database Record © 2013 APA, all rights reserved).

Concepts: Psychology, Evidence-based medicine, Systematic review, Randomized controlled trial, Statistical significance, Meta-analysis, All rights reserved, Critical appraisal


One of the best sources for high quality information about healthcare interventions is a systematic review. A well-conducted systematic review includes a comprehensive literature search. There is limited empiric evidence to guide the extent of searching, in particular the number of electronic databases that should be searched. We conducted a cross-sectional quantitative analysis to examine the potential impact of selective database searching on results of meta-analyses.

Concepts: Medicine, Research methods, Evidence-based medicine, Systematic review, Randomized controlled trial, Meta-analysis, Search engine optimization, Critical appraisal


Evidence based medicine tells us that we should not accept published research at face value. Even research from established teams published in the highest impact journals can have methodological flaws, biases and limited generalisability. The critical appraisal of research studies can seem daunting, but tools are available to make the process easier for the non-specialist. Understanding the language and process of quality assessment is essential when considering or conducting research, and is also valuable for all clinicians who use published research to inform their clinical practice.We present a review written specifically for the practising geriatrician. This considers how quality is defined in relation to the methodological conduct and reporting of research. Having established why quality assessment is important, we present and critique tools which are available to standardise quality assessment. We consider five study designs: RCTs, non-randomised studies, observational studies, systematic reviews and diagnostic test accuracy studies. Quality assessment for each of these study designs is illustrated with an example of published cognitive research. The practical applications of the tools are highlighted, with guidance on their strengths and limitations. We signpost educational resources and offer specific advice for use of these tools.We hope that all geriatricians become comfortable with critical appraisal of published research and that use of the tools described in this review - along with awareness of their strengths and limitations - become a part of teaching, journal clubs and practice.

Concepts: Scientific method, Critical thinking, Evaluation, Evidence-based medicine, Systematic review, Educational psychology, Meta-analysis, Critical appraisal


Objective To investigate whether the success rate of retrieving individual participant data (IPD) for use in IPD meta-analyses has increased over time, and to explore the characteristics associated with IPD retrieval.Design Systematic review of published IPD meta-analyses, supplemented by a reflection of the Cochrane Epilepsy Group’s 20 years' experience of requesting IPD.Data sources Medline, CENTRAL, Scopus, Web of Science, CINAHL Plus, and PsycINFO.Eligibility criteria for study selection IPD meta-analyses of studies of all designs and all clinical areas published in English.Results 760 IPD meta-analyses which identified studies by systematic methods that had been published between 1987 and 2015 were included. Only 188 (25%) of these IPD meta-analyses retrieved 100% of the eligible IPD for analysis, with 324 (43%) of these IPD meta-analyses retrieving 80% or more of relevant IPD. There is insufficient evidence to suggest that IPD retrieval rates have improved over time. IPD meta-analyses that included only randomised trials, had an authorship policy, included fewer eligible participants, and were conducted outside of the Cochrane Database of Systematic Reviews were associated with a high or complete IPD retrieval rate. There was no association between the source of funding of the IPD meta-analyses and IPD retrieval rate. The IPD retrieval rate of the Cochrane Epilepsy Group has declined from 83% (up to 2005) to 65% (between 2012 and 2015) and the reported reasons for lack of data availability have changed in recent years.Conclusions IPD meta-analyses are considered to be the “gold standard” for the synthesis of data from clinical research studies; however, only 25% of published IPD meta-analyses have had access to all IPD.

Concepts: Medicine, Evidence-based medicine, Systematic review, Randomized controlled trial, Clinical research, Meta-analysis, Review journal, Critical appraisal


Evidence-based policy (EBP), a concept modelled on the principles of evidence-based medicine (EBM), is widely used in different areas of policymaking. Systematic reviews (SRs) with meta-analyses gradually became the methods of choice for synthesizing research evidence about interventions and judgements about quality of evidence and strength of recommendations. Critics have argued that the relation between research evidence and service policies is weak, and that the notion of EBP rests on a misunderstanding of policy processes. Having explored EBM standards and knowledge requirements for health policy decision-making, we present an empirical point of departure for discussing the relationship between EBM and EBP.

Concepts: Scientific method, Medicine, Evidence-based medicine, Systematic review, Randomized controlled trial, Avicenna, Meta-analysis, Critical appraisal


Systematic reviews of the literature occupy the highest position in currently proposed hierarchies of evidence. The aims of this study were to assess whether citation classics exist in published systematic review and meta-analysis (SRM), examine the characteristics of the most frequently cited SRM articles, and evaluate the contribution of different world regions.

Concepts: Evidence-based medicine, Systematic review, Randomized controlled trial, Educational psychology, Writing, Meta-analysis, Review journal, Critical appraisal


Evidence is mounting to suggest a causal relationship between the built environment and people’s physical activity behaviours, particularly active transport. The evidence base has been hindered to date by restricted consideration of cost and economic factors associated with built environment interventions, investigation of socioeconomic or ethnic differences in intervention effects, and an inability to isolate the effect of the built environment from other intervention types. The aims of this systematic review were to identify which environmental interventions increase physical activity in residents at the local level, and to build on the evidence base by considering intervention cost, and the differential effects of interventions by ethnicity and socioeconomic status.

Concepts: Evidence-based medicine, Systematic review, Randomized controlled trial, Natural environment, Economics, Meta-analysis, Metaphysics, Critical appraisal