Construct validity of the Physiotherapy Evidence Database (PEDRo) quality scale for randomized trials: Item Response Theory analyses
ConclusionsOur findings question the construct validity of the PEDro scale to assess the methodological quality of clinical trials. PEDro summary scores should not be used; rather the physiotherapy community should consider working with the individual items of the scale. (Source: Research Synthesis Methods)
Source: Research Synthesis Methods - November 16, 2019 Category: Chemistry Authors: Emiliano Albanese, Lukas B ütikofer, Susan Armijo‐Olivo, Christine Ha, Matthias Egger Tags: RESEARCH ARTICLE Source Type: research

Influence diagnostics and outlier detection for meta ‐analysis of diagnostic test accuracy
SummaryMeta ‐analyses of diagnostic test accuracy (DTA) studies have been gaining prominence in research in clinical epidemiology and health technology development. In these DTA meta‐analyses, some studies may have markedly different characteristics from the others, and potentially be inappropriate to inclu de. The inclusion of these “outlying” studies might lead to biases, yielding misleading results. In addition, there might be influential studies that have notable impacts on the results. In this article, we propose Bayesian methods for detecting outlying studies and their influence diagnostics i n DTA me...
Source: Research Synthesis Methods - November 14, 2019 Category: Chemistry Authors: Yuki Matsushima, Hisashi Noma, Tomohide Yamada, Toshi A. Furukawa Tags: RESEARCH ARTICLE Source Type: research

Developing methods for the overarching synthesis of quantitative and qualitative evidence: the interweave synthesis approach
We present two case studies in which we used novel and innovative methods to draw together the findings from individual but related quantitative and qualitative syntheses to aid interpretation of the overall evidence base. Our approach moved beyond making a choice between parallel, sequential or convergent methods to interweave the findings of individual reviews and offers three key innovations to mixed ‐methods synthesis methods: The use of intersubjective questions to understand the findings of the individual reviews through different lenses, Immersion of key reviewers in the entirety of the evidence base, and Commenc...
Source: Research Synthesis Methods - November 14, 2019 Category: Chemistry Authors: Jo Thompson Coon, Ruth Gwernan ‐Jones, Ruth Garside, Michael Nunns, Liz Shaw, G.J. Melendez‐Torres, Darren Moore Tags: RESEARCH ARTICLE Source Type: research

The “Realist Search”: a systematic scoping review of current practice and reporting
This study reviews reports of search methods in 34 realist reviews published withi n the calendar year of 2016. Data from all eligible reviews were extracted against the search framework. Realist search reports poorly differentiate between the different search components. Review teams often conduct a single “big bang” multi‐purpose search to fulfil multiple functions within the review. However, it is acknowledged that realist searches are likely to be iterative and responsive to emergent data. Overall the search for empirical studies appears most comprehensive in conduct and reporting detail. In contrast, sea...
Source: Research Synthesis Methods - November 12, 2019 Category: Chemistry Authors: Andrew Booth, Simon Briscoe, Judy M. Wright Tags: REVIEW Source Type: research

A novel approach for identifying and addressing case ‐mix heterogeneity in individual participant data meta‐analysis
Case ‐mix heterogeneity across studies complicates meta‐analyses. As a result of this, treatments that are equally effective on patient subgroups may appear to have different effectiveness on patient populations with different case mix. It is therefore important that meta‐analyses be explicit for w hat patient population they describe the treatment effect. To achieve this, we develop a new approach for meta‐analysis of randomized clinical trials, which use individual patient data (IPD) from all trials to infer the treatment effect for the patient population in a given trial, based on direct standardization using ei...
Source: Research Synthesis Methods - November 4, 2019 Category: Chemistry Authors: Tat ‐Thang Vo, Raphael Porcher, Anna Chaimani, Stijn Vansteelandt Tags: RESEARCH ARTICLE Source Type: research

Pathway ‐based meta‐analysis for partially paired transcriptomics analysis
This study demonstrated the utility of our newly developed pathway ‐based meta‐analysis that allows the incorporation of partially paired or paired samples. The proposed framework can be applied to omics data including but not limited to transcriptomics data. (Source: Research Synthesis Methods)
Source: Research Synthesis Methods - November 4, 2019 Category: Chemistry Authors: Wing Tung Fung, Joseph T. Wu, Wai Man Mandy Chan, Henry H. Chan, Herbert Pang Tags: RESEARCH ARTICLE Source Type: research

Joint synthesis of conditionally related multiple outcomes makes better use of data than separate meta ‐analyses
ConclusionMultiple outcomes should be synthesised together where possible, taking account of their structural relationships. This generates an internally coherent analysis, suitable for decision making, in which estimates of each of the treatment effects are based on all available evidence (direct and indirect). Separate meta ‐analyses of each outcome have none of these properties. (Source: Research Synthesis Methods)
Source: Research Synthesis Methods - November 4, 2019 Category: Chemistry Authors: Sumayya Anwer, A.E. Ades, Sofia Dias Tags: RESEARCH ARTICLE Source Type: research

From registration to publication; a study on Dutch academic randomized controlled trials
ConclusionThis study shows that approximately one out of four Dutch investigator ‐initiated RCTs remains unpublished five years after initiation. The observed low overall consistency with the initial study outline is a matter of concern, and warrants improvements in trial design and assessment of trial feasibility. (Source: Research Synthesis Methods)
Source: Research Synthesis Methods - October 15, 2019 Category: Chemistry Authors: Joost Huiskens, B.R.J. Kool, Jean ‐Michel Bakker, E.R.J. Bruns, S.W. Jonge, Pim B. Olthof, Belle V. Rosmalen, Thomas M. Gulik, Lotty Hooft, Cornelis J.A. Punt Tags: RESEARCH ARTICLE Source Type: research

Which Academic Search Systems are Suitable for Systematic Reviews or Meta ‐Analyses? Evaluating Retrieval Qualities of Google Scholar, PubMed and 26 other Resources
This study investigates and compares the systematic search qualities of 28 widely used academic search systems, including Google Scholar, PubMed and Web of Science. A novel, query ‐based method tests how well users are able to interact and retrieve records with each system. The study is the first to show the extent to which search systems can effectively and efficiently perform (Boolean) searches with regards to precision, recall and reproducibility. We found substantial di fferences in the performance of search systems, meaning that their usability in systematic searches varies. Indeed, only half of the search systems a...
Source: Research Synthesis Methods - October 15, 2019 Category: Chemistry Authors: Michael Gusenbauer, Neal R. Haddaway Tags: RESEARCH ARTICLE Source Type: research

Assessing the impact of a matching ‐adjusted indirect comparison in a Bayesian network meta‐analysis
If IPD is available for some or all trials in a network meta ‐analysis (NMA), then incorporating this IPD into an NMA is routinely considered to be preferable. However, the situation often arises where a researcher has IPD for trials concerning a particular treatment (eg, from a sponsor) but none for other trials. Therefore, one can reweight the IPD so that the covariate characteristics in the IPD trials match that of the aggregate data (AgD) trials, using a matching‐adjusted indirect comparison (MAIC). We assess the impact of using the reweighted aggregated data, obtained by the MAIC, in a Bayesian NMA for a connected...
Source: Research Synthesis Methods - October 14, 2019 Category: Chemistry Authors: Joy Leahy, Cathal Walsh Tags: RESEARCH ARTICLE Source Type: research

MetaInsight: An interactive web ‐based tool for analyzing, interrogating, and visualizing network meta‐analyses using R‐shiny and netmeta
ConclusionsWe believe that many researchers will find our package helpful for facilitating NMA as well as allowing decision makers to scrutinize presented results visually and in real time. This will impact on the relevance of statistical analyses for health care decision making and sustainably increase capacity by empowering informed nonspecialists to be able to conduct more clinically relevant reviews. It is also hoped that others will be inspired to create similar tools for other advanced specialist analyses methods using the freely available technologies we have adopted. (Source: Research Synthesis Methods)
Source: Research Synthesis Methods - October 11, 2019 Category: Chemistry Authors: Rhiannon K. Owen, Naomi Bradbury, Yiqiao Xin, Nicola Cooper, Alex Sutton Tags: RESEARCH ARTICLE Source Type: research

Issue information
No abstract is available for this article. (Source: Research Synthesis Methods)
Source: Research Synthesis Methods - September 9, 2019 Category: Chemistry Tags: ISSUE INFORMATION Source Type: research

The dark side of the force: multiplicity issues in network meta ‐analysis and how to address them
We present a set of alternative models for network meta‐analysis, and we show in simulations that in several scenarios, such models perform better than the usual network meta‐analysis model. (Source: Research Synthesis Methods)
Source: Research Synthesis Methods - September 2, 2019 Category: Chemistry Authors: Orestis Efthimiou, Ian R. White Tags: RESEARCH ARTICLE Source Type: research

Systematic Reviews in Health Research
Research Synthesis Methods, Volume 0, Issue ja, -Not available-. (Source: Research Synthesis Methods)
Source: Research Synthesis Methods - August 28, 2019 Category: Chemistry Authors: Emily E. Tanner ‐Smith, Matthias Egger, Julian Higgins Tags: EDITORIAL Source Type: research

Empirical comparison of univariate and multivariate meta ‐analyses in Cochrane Pregnancy and Childbirth reviews with multiple binary outcomes
ConclusionsMVMA methods can be applied only in a minority of reviews of interventions in pregnancy and childbirth and can be difficult to apply because of missing correlations or lack of convergence. Nevertheless, clinical and/or statistical conclusions from MVMA may occasionally differ from those from univariate analyses. (Source: Research Synthesis Methods)
Source: Research Synthesis Methods - August 12, 2019 Category: Chemistry Authors: Malcolm J. Price, Helen A. Blake, Sara Kenyon, Ian R. White, Dan Jackson, Jamie J. Kirkham, James P. Neilson, Jonathan J. Deeks, Richard D. Riley Tags: RESEARCH ARTICLE Source Type: research

Comparison of information sources used in Cochrane and non ‐Cochrane systematic reviews: a case study in the field of anesthesiology and pain
ConclusionSRs in the field of anesthesiology and pain often neglect to search all possible information sources, particularly in NCSRs. Cochrane reviews had more comprehensive searching and shorter search to publication time. (Source: Research Synthesis Methods)
Source: Research Synthesis Methods - August 8, 2019 Category: Chemistry Authors: Marina Biocic, Mahir Fidahic, Karla Cikes, Livia Puljak Tags: RESEARCH ARTICLE Source Type: research

Assessing the Impact of a Matching Adjusted Indirect Comparison in a Bayesian Network Meta Analysis
If IPD is available for some or all trials in an NMA, then incorporating this IPD into an NMA is routinely considered to be preferable. However, the situation often arises where a researcher has IPD for trials concerning a particular treatment (for example from a sponsor), but none for other trials. Therefore, one can reweight the IPD so that the covariate characteristics in the IPD trials match that of the aggregate data (AgD) trials, using a Matching Adjusted Indirect Comparison (MAIC).We assess the impact of using the reweighted aggregated data, obtained by the MAIC, in a Bayesian NMA for a connected treatment network. ...
Source: Research Synthesis Methods - August 1, 2019 Category: Chemistry Authors: Joy Leahy, Cathal Walsh Tags: RESEARCH ARTICLE Source Type: research

revtools: An R package to support article screening for evidence synthesis
The field of evidence synthesis is growing rapidly, with a corresponding increase in the number of software tools and workflows to support the construction of systematic reviews, systematic maps, and meta ‐analyses. Despite much progress, however, a number of problems remain including slow integration of new statistical or methodological approaches into user‐friendly software, low prevalence of open‐source software, and poor integration among distinct software tools. These issues hinder the uti lity and transparency of new methods to the research community. Here I present revtools, an R package to support article scr...
Source: Research Synthesis Methods - July 29, 2019 Category: Chemistry Authors: Martin J. Westgate Tags: COMPUTATIONAL TOOLS AND METHODS Source Type: research

MetaInsight: An interactive web ‐based tool for analyzing, interrogating and visualizing network meta‐analyses using R‐shiny and netmeta
ConclusionsWe believe many researchers will find our package helpful for facilitating NMA as well as allowing decision ‐makers to scrutinize presented results visually and in real‐time. This will impact on the relevance of statistical analyses for healthcare decision‐making, and sustainably increase capacity by empowering informed non‐specialists to be able to conduct more clinically relevant reviews. It is also hoped that others will be inspired to create similar tools for other advanced specialist analyses methods using the freely available technologies we have adopted. (Source: Research Synthesis Methods)
Source: Research Synthesis Methods - July 26, 2019 Category: Chemistry Authors: Rhiannon K. Owen, Naomi Bradbury, Yiqiao Xin, Nicola Cooper, Alex Sutton Tags: RESEARCH ARTICLE Source Type: research

Random ‐effects meta‐analysis of few studies involving rare events
Meta ‐analyses of clinical trials targeting rare events face particular challenges when the data lack adequate numbers of events for all treatment arms. Especially when the number of studies is low, standard random‐effects meta‐analysis methods can lead to serious distortions because of such data s parsity. To overcome this, we suggest the use ofweakly informative priors (WIP) for the treatment effect parameter of a Bayesian meta ‐analysis model, which may also be seen as a form of penalization. As a data model, we use a binomial‐normal hierarchical model (BNHM) which does not require continuity corrections in ca...
Source: Research Synthesis Methods - July 26, 2019 Category: Chemistry Authors: Burak K ürsad Günhan, Christian Röver, Tim Friede Tags: RESEARCH ARTICLE Source Type: research

Shared parameter model for competing risks and different data summaries in meta ‐analysis: implications for common and rare outcomes
This paper considers the problem in aggregate data meta ‐analysis of studies reporting multiple competing binary outcomes, and of studies using different summary formats for those outcomes. For example, some may report numbers of patients with at least one of each outcome while others may report the total number of such outcomes. We develop a shared pa rameter model on hazard ratio scale accounting for different data summaries and competing risks. We adapt theoretical arguments from the literature to demonstrate that the models are equivalent if events are rare. We use constructed data examples and a simulation study to ...
Source: Research Synthesis Methods - July 22, 2019 Category: Chemistry Authors: Howard Thom, Jos é A. López‐López, Nicky J. Welton Tags: RESEARCH ARTICLE Source Type: research

Semiautomated text analytics for qualitative data synthesis
Approaches to synthesizing qualitative data have, to date, largely focused on integrating the findings from published reports. However, developments in text mining software offer the potential for efficient analysis of large pooled primary qualitative datasets. This case study aimed to (a) provide a step ‐by‐step guide to using one software application, Leximancer, and (b) interrogate opportunities and limitations of the software for qualitative data synthesis. We applied Leximancer v4.5 to a pool of five qualitative, UK‐based studies on transportation such as walking, cycling, and driving, an d displayed the finding...
Source: Research Synthesis Methods - July 9, 2019 Category: Chemistry Authors: Emily Haynes, Ruth Garside, Judith Green, Michael P. Kelly, James Thomas, Cornelia Guell Tags: RESEARCH ARTICLE Source Type: research

The Value of a Second Reviewer for Study Selection in Systematic Reviews
ConclusionsUsing a second reviewer throughout the entire study screening process can increase the number of relevant studies identified for use in a systematic review. Systematic review performers should consider using a complete dual review process to ensure all relevant studies are included in their review. (Source: Research Synthesis Methods)
Source: Research Synthesis Methods - July 4, 2019 Category: Chemistry Authors: Carolyn Stoll, Sonya Izadi, Susan Fowler, Paige Green, Jerry Suls, Graham A. Colditz Tags: RESEARCH ARTICLE Source Type: research

Difficulties arising in reimbursement recommendations on new medicines due to inadequate reporting of population adjustment indirect comparison methods
We describe some shared observations on areas wher e reporting of population‐adjustment indirect comparison methods are causing uncertainty in our recommendations to decision making committees when assessing reimbursement of medicines. (Source: Research Synthesis Methods)
Source: Research Synthesis Methods - June 27, 2019 Category: Chemistry Authors: Eileen M. Holmes, Joy Leahy, Cathal D. Walsh, Arthur White, Peter T. Donnan, Felicity Lamrock Tags: BRIEF METHOD NOTE Source Type: research

Meta ‐analysis of full ROC curves: Additional flexibility by using semiparametric distributions of diagnostic test values
AbstractDiagnostic test accuracy studies frequently report on sensitivities and specificities for more than one threshold of the diagnostic test under study. Although it is obvious that the information from all thresholds should be used for a meta ‐analysis, in practice frequently only a single pair of sensitivity and specificity is selected. To overcome this disadvantage, we recently proposed a statistical model for the meta‐analysis of such full receiver operating characteristic (ROC) curves that uses the relationship between a ROC curv e and a bivariate model for interval‐censored data. In this model, diagnostic t...
Source: Research Synthesis Methods - June 24, 2019 Category: Chemistry Authors: Annika Hoyer, Oliver Kuss Tags: RESEARCH ARTICLE Source Type: research

A comparison of Bayesian synthesis approaches for studies comparing two means: A tutorial
AbstractResearchers often seek to synthesize results of multiple studies on the same topic to draw statistical or substantive conclusions and to estimate effect sizes that will inform power analyses for future research. The most popular synthesis approach is meta ‐analysis. There have been few discussions and applications of other synthesis approaches. This tutorial illustrates and compares multiple Bayesian synthesis approaches (i.e., integrative data analyses, meta‐analyses, data fusion using augmented datadependent priors, and data fusion using aggreg ated data‐dependent priors), and discusses when and how to use ...
Source: Research Synthesis Methods - June 22, 2019 Category: Chemistry Authors: Han Du, Thomas N. Bradbury, Justin A. Lavner, Andrea L. Meltzer, James K. McNulty, Lisa A. Neff, Benjamin R. Karney Tags: TUTORIAL Source Type: research

Machine learning with the hierarchy ‐of‐hypotheses (HoH) approach discovers novel pattern in studies on biological invasions
This study shows that machine learning, equation‐free statistical modeling of artificial intelligence, is a promising synthesis tool for discovering novel patterns and the source of controversy in a general hypothesis. We apply a decision tree algorithm, assuming that evidence from various contexts can be adequately integrated in a hierarchically nested structure. As a case study, we analyzed 163 articles that studied a prominent hypothesis in invasion biology, the enemy release hypothesis. We explored if any of nine attr ibutes that classify each study can differentiate conclusions, as classification problem. Results co...
Source: Research Synthesis Methods - June 20, 2019 Category: Chemistry Authors: Masahiro Ryo, Jonathan M. Jeschke, Matthias C. Rillig, Tina Heger Tags: RESEARCH ARTICLE Source Type: research

Issue Information
No abstract is available for this article. (Source: Research Synthesis Methods)
Source: Research Synthesis Methods - June 6, 2019 Category: Chemistry Tags: ISSUE INFORMATION Source Type: research

Potential Technologies Review: A hybrid information retrieval framework to accelerate demand ‐pull innovation in biomedical engineering
Launching biomedical innovations based on clinical demands instead of translating basic research findings to practice reduces the risk that the results will not fit the clinical routine. To realize this type of innovation, a meta ‐analysis of the body of research is necessary to reveal demand‐matching concepts. However, both the data deluge and the narrow time constraints for innovation make it impossible to perform such reviews manually. Thus, this paper proposes a specifically adapted “Potential Technologies Review” approach focusing on automated text mining and information retrieval techniques. The novel...
Source: Research Synthesis Methods - June 2, 2019 Category: Chemistry Authors: Tom Schmitz, Mark Bukowski, Steffen Koschmieder, Thomas Schmitz ‐Rode, Robert Farkas Tags: RESEARCH ARTICLE Source Type: research

Estimating hazard ratios from published Kaplan ‐Meier survival curves: A methods validation study
ConclusionIn the absence of reported HRs, we recommend that researchers consider the Guyot method to reconstruct HRs from KM curves when performing aggregate data meta ‐analyses. (Source: Research Synthesis Methods)
Source: Research Synthesis Methods - May 27, 2019 Category: Chemistry Authors: Ronak Saluja, Sierra Cheng, Keemo Althea delos Santos, Kelvin K.W. Chan Tags: RESEARCH ARTICLE Source Type: research

Conduct and reporting of citation searching in Cochrane systematic reviews: a cross ‐sectional study
ConclusionThe conduct of backward citation searching was more uniform than forward citation searching. This might be due to lack of MECIR guidance for forward citation searching. Reporting was generally compliant with MECIR but this is not always sufficient to ensure full transparency. (Source: Research Synthesis Methods)
Source: Research Synthesis Methods - May 25, 2019 Category: Chemistry Authors: Simon Briscoe, Alison Bethel, Morwenna Rogers Tags: RESEARCH ARTICLE Source Type: research

Semi ‐automated text analytics for qualitative data synthesis
Approaches to synthesising qualitative data have, to date, largely focused on integrating the findings from published reports. However, developments in text mining software offer the potential for efficient analysis of large pooled primary qualitative datasets. This case study aimed to: a) provide a step ‐by‐step guide to using one software application, Leximancer; and b) interrogate opportunities and limitations of the software for qualitative data synthesis. We applied Leximancer v4.5 to a pool of five qualitative, UK‐based studies on transportation such as walking, cycling and driving, and displayed the findings o...
Source: Research Synthesis Methods - May 24, 2019 Category: Chemistry Authors: Emily Haynes, Ruth Garside, Judith Green, Michael P. Kelly, James Thomas, Cornelia Guell Tags: RESEARCH ARTICLE Source Type: research

A new justification of the Hartung ‐Knapp method for random‐effects meta‐analysis based on weighted least squares regression
The Hartung ‐Knapp method for random‐effects meta‐analysis, that was also independently proposed by Sidik and Jonkman, is becoming advocated for general use. This method has previously been justified by taking all estimated variances as known and using a different pivotal quantity to the more conventional one when making inferences about the average effect. We provide a new conceptual framework for, and justification of, the Hartung‐Knapp method. Specifically we show that inferences from fitted random‐effects models, using both the conventional and the Hartung‐Knapp method, are equivalent to t hose from closely...
Source: Research Synthesis Methods - May 20, 2019 Category: Chemistry Authors: Robbie C.M. Aert, Dan Jackson Tags: RESEARCH ARTICLE Source Type: research

Best Practice Guidelines for Abstract Screening Large ‐Evidence Systematic Reviews and Meta‐Analyses
Abstract screening is one important aspect of conducting a high ‐quality and comprehensive systematic review and meta‐analysis. Abstract screening allows the review team to conduct the tedious but vital first step to synthesize the extant literature: winnowing down the overwhelming amalgamation of citations discovered through research databases to the citati ons that should be “full‐text” screened and eventually included in the review. Although it is a critical process, few guidelines have been put forth since the publications of seminal systematic review textbooks. The purpose of this paper, therefore, i...
Source: Research Synthesis Methods - May 14, 2019 Category: Chemistry Authors: Joshua R. Polanin, Terri D. Pigott, Dorothy L. Espelage, Jennifer Grotpeter Tags: TUTORIAL Source Type: research

Empirical comparison of univariate and multivariate meta ‐analysis in Cochrane Pregnancy and Childbirth reviews with multiple binary outcomes
ConclusionsMVMA methods can be applied only in a minority of reviews of interventions in pregnancy and childbirth, and can be difficult to apply due to missing correlations or lack of convergence. Nevertheless, clinical and/or statistical conclusions from MVMA may occasionally differ from those from univariate analyses. (Source: Research Synthesis Methods)
Source: Research Synthesis Methods - May 6, 2019 Category: Chemistry Authors: M.J. Price, H. Blake, S. Kenyon, I.R. White, D. Jackson, J.J. Kirkham, J. Neilson, J.J. Deeks, R.D. Riley Tags: RESEARCH ARTICLE Source Type: research

A Kinked Meta ‐Regression Model for Publication Bias Correction
AbstractPublication bias distorts the available empirical evidence and misinforms policymaking. Evidence of publication bias is mounting in virtually all fields of empirical research. This paper proposes the Endogenous Kink (EK) meta ‐regression model as a novel method of publication bias correction. The EK method fits a piecewise linear meta‐regression of the primary estimates on their standard errors, with a kink at the cutoff value of the standard error below which publication selection is unlikely. We provide a simple me thod of endogenously determining this cutoff value as a function of a first‐stage estimate of...
Source: Research Synthesis Methods - April 30, 2019 Category: Chemistry Authors: Pedro R. D. Bom, Heiko Rachinger Tags: RESEARCH ARTICLE Source Type: research

Modelling time ‐course relationships with multiple treatments: Model‐Based Network Meta‐Analysis for continuous summary outcomes
ConclusionsTime ‐course MBNMA provides a statistically robust framework for synthesising evidence on multiple treatments at multiple time points. The use of placebo‐controlled studies in drug‐development means there is limited potential for inconsistency. The methods can inform drug‐development decisions, a nd provide the rigour needed in the reimbursement decision‐making process. (Source: Research Synthesis Methods)
Source: Research Synthesis Methods - April 23, 2019 Category: Chemistry Authors: H. Pedder, S. Dias, M. Bennetts, M. Boucher, N.J. Welton Tags: RESEARCH ARTICLE Source Type: research

Potential Technologies Review – A hybrid information retrieval framework to accelerate demand‐pull innovation in biomedical engineering
Launching biomedical innovations based on clinical demands instead of translating basic research findings to practice reduces the risk that the results will not fit the clinical routine. To realize this type of innovation, a meta ‐analysis of the body of research is necessary to reveal demand‐matching concepts. However, both the data deluge and the narrow time constraints for innovation make it impossible to perform such reviews manually. Thus, this paper proposes a specifically adapted ‘Potential Technologies Review’ approach focusing on automated text mining and information retrieval techniques.The novel ...
Source: Research Synthesis Methods - April 17, 2019 Category: Chemistry Authors: T. Schmitz, M. Bukowski, S. Koschmieder, T. Schmitz ‐Rode, R. Farkas Tags: RESEARCH ARTICLE Source Type: research

Dealing with missing outcome data in meta ‐analysis
Missing data result in less precise and possibly biased effect estimates in single studies. Bias arising from studies with incomplete outcome data is naturally propagated in a meta ‐analysis. Conventional analysis using only individuals with available data is adequate when the meta‐analyst can be confident that the data are missing at random (MAR) in every study ‐ that is, that the probability of missing data does not depend on unobserved variables, conditional on observ ed variables. Usually such confidence is unjustified as participants may drop out due to lack of improvement or adverse effects. The MAR assumption ...
Source: Research Synthesis Methods - April 16, 2019 Category: Chemistry Authors: Dimitris Mavridis, Ian R. White Tags: REVIEW Source Type: research

Seriously misleading results using inverse of freeman ‐tukey double arcsine transformation in meta‐analysis of single proportions
Standard generic inverse variance methods for the combination of single proportions are based on transformed proportions using the logit, arcsine, and Freeman ‐Tukey double arcsine transformations. Generalized linear mixed models are another more elaborate approach. Irrespective of the approach, meta‐analysis results are typically back‐transformed to the original scale in order to ease interpretation. Whereas the back‐transformation of meta‐anal ysis results is straightforward for most transformations, this is not the case for the Freeman‐Tukey double arcsine transformation, albeit possible.In this case study w...
Source: Research Synthesis Methods - April 4, 2019 Category: Chemistry Authors: Guido Schwarzer, Hiam Chemaitelly, Laith J. Abu ‐Raddad, Gerta Rücker Tags: BRIEF METHOD NOTE Source Type: research

Issue Information
No abstract is available for this article. (Source: Research Synthesis Methods)
Source: Research Synthesis Methods - March 19, 2019 Category: Chemistry Tags: ISSUE INFORMATION Source Type: research

Meta ‐Analysis and Mendelian randomization: A review
Mendelian randomization (MR) uses genetic variants as instrumental variables to infer whether a risk factor causally affects a health outcome. Meta ‐analysis has been used historically in MR to combine results from separate epidemiological studies, with each study using a small but select group of genetic variants. In recent years it has been used to combine genome‐wide association study (GWAS) summary data for large numbers of genetic vari ants. Heterogeneity amongst the causal estimates obtained from multiple genetic variants points to a possible violation of the necessary instrumental variable assumptions. In this a...
Source: Research Synthesis Methods - March 12, 2019 Category: Chemistry Authors: Jack Bowden, Michael V. Holmes Tags: REVIEW Source Type: research

Pitfalls of using the risk ratio in meta ‐analysis
For meta ‐analysis of studies that report outcomes as binomial proportions, the most popular measure of effect is the odds ratio (OR), usually analyzed as log(OR). Many meta‐analyses use the risk ratio (RR) and its logarithm, because of its simpler interpretation. Although log(OR) and log(RR) are both un bounded, use of log(RR) must ensure that estimates are compatible with study‐level event rates in the interval (0, 1). These complications pose a particular challenge for random‐effects models, both in applications and in generating data for simulations. As background we review the conventional random‐effects mod...
Source: Research Synthesis Methods - March 10, 2019 Category: Chemistry Authors: Ilyas Bakbergenuly, David C. Hoaglin, Elena Kulinskaya Tags: RESEARCH ARTICLE Source Type: research

A Simple Method to Estimate Prediction Intervals and Predictive Distributions: Summarizing Meta ‐analyses Beyond Means and Confidence Intervals
A systematic review and meta ‐analysis is an important step in evidence synthesis. The current paradigm for meta‐analyses requires a presentation of the means under a random‐effects model; however, a mean with a confidence interval provides an incomplete summary of the underlying heterogeneity in meta‐analysis. Predicti on intervals show the range of true effects in future studies and have been advocated to be regularly presented. Most commonly, prediction intervals are estimated assuming that the underlying heterogeneity follows a normal distribution, which is not necessarily appropriate. In this article, we provi...
Source: Research Synthesis Methods - March 5, 2019 Category: Chemistry Authors: Chia ‐Chun Wang, Wen‐Chung Lee Tags: RESEARCH ARTICLE Source Type: research

Evaluating network meta ‐analysis and inconsistency using arm‐parameterized model in structural equation modeling
Network meta ‐analysis (NMA) uses both direct and indirect evidence to compare the efficacy and harm between several treatments. Structural equation modeling (SEM) is a statistical method that investigates relations among observed and latent variables. Previous studies have shown that the contrast‐based Lu‐ Ades model for NMA can be implemented in the SEM framework. However, the Lu‐Ades model uses the difference between treatments as the unit of analysis, thereby introducing correlations between observations. The main objective of this study is to demonstrate how to undertake NMA in SEM using the out come of treatm...
Source: Research Synthesis Methods - March 4, 2019 Category: Chemistry Authors: Ming ‐Chieh Shih, Yu‐Kang Tu Tags: RESEARCH ARTICLE Source Type: research

Reviewer Appreciation
Research Synthesis Methods, Volume 0, Issue ja, -Not available-. (Source: Research Synthesis Methods)
Source: Research Synthesis Methods - March 3, 2019 Category: Chemistry Tags: LIST OF REVIEWERS Source Type: research

Systematic reviews of health economic evaluations: a structured analysis of characteristics and methods applied
ConclusionsOverall, we identified few common features in the applied methods for SR ‐HEs. The information retrieval processes are largely standardized but many studies did not use validated search filters. For the other systematic review steps the methodological approaches varied. In particular, important challenges seem to be the methodological quality and transferability assess ment as well as presentation and (quantitative) synthesis of results. Efforts are needed for increasing standardization, quality of applied methods, and reporting of SR‐HEs. (Source: Research Synthesis Methods)
Source: Research Synthesis Methods - February 13, 2019 Category: Chemistry Authors: Miriam Luhnen, Barbara Prediger, Edmund A.M. Neugebauer, Tim Mathes Tags: REVIEW Source Type: research

Developing and testing intervention theory by incorporating a views synthesis into a qualitative comparative analysis of intervention effectiveness
Qualitative comparative analysis (QCA) was originally developed as a tool for cross ‐national comparisons in macrosociology, but its use in evaluation and evidence synthesis of complex interventions is rapidly developing. QCA is theory‐driven and relies on Boolean logic to identify pathways to an outcome (e.g. is the intervention effective or not?). We use the example of two li nked systematic reviews on weight management programmes (WMPs) for adults—one focusing on user views (a ‘views synthesis’) and one focusing on the effectiveness of WMPs incorporating dietary and physical activity—to demon...
Source: Research Synthesis Methods - February 8, 2019 Category: Chemistry Authors: G.J. Melendez ‐Torres, Katy Sutcliffe, Helen E.D. Burchett, Rebecca Rees, James Thomas Tags: RESEARCH ARTICLE Source Type: research

Graphical augmentations to sample ‐size‐based funnel plot in meta‐analysis
This article introduces contours for sample‐size‐based funnel plots of various effect sizes , which may help meta‐analysts properly interpret such plots’ asymmetry. We provide five examples to illustrate the use of the proposed contours. (Source: Research Synthesis Methods)
Source: Research Synthesis Methods - January 21, 2019 Category: Chemistry Authors: Lifeng Lin Tags: RESEARCH ARTICLE Source Type: research

A flexible approach to identify interaction effects between moderators in meta ‐analysis
In meta ‐analytic studies, there are often multiple moderators available (eg, study characteristics). In such cases, traditional meta‐analysis methods often lack sufficient power to investigate interaction effects between moderators, especially high‐order interactions. To overcome this problem, meta‐ CART was proposed: an approach that applies classification and regression trees (CART) to identify interactions, and then subgroup meta‐analysis to test the significance of moderator effects. The aim of this study is to improve meta‐CART upon two aspects: 1) to integrate the two steps of the app roach into one and ...
Source: Research Synthesis Methods - January 9, 2019 Category: Chemistry Authors: Xinru Li, Elise Dusseldorp, Jacqueline J. Meulman Tags: RESEARCH ARTICLE Source Type: research