A method of meta-mechanism combination and replacement based on motion study

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Yadong Fang

2015-01-01

Full Text Available Lacking the effective methods to reduce labor and cost, many small- and medium-sized assembly companies are facing with the problem of high cost for a long time. In order to reduce costs of manual operations, the method of meta-mechanism combination and replacement is studied. In this paper, we mainly discuss assembling motion analysis, workpieces position information acquisition, motion library construction, assembling motion analysis by Maynard’s operation sequence technique, meta-mechanism database establishment, and match of motion and mechanism. At the same time, the principle, process, and system realization framework of mechanism replacement are introduced. Lastly, problems for low-cost automation of the production line are basically resolved by operator motion analysis and meta-mechanism combination and match.

Combination of pharmacotherapy and psychotherapy in the treatment of chronic depression: A systematic review and meta-analysis

Science.gov (United States)

2012-01-01

Background Chronic depression represents a substantial portion of depressive disorders and is associated with severe consequences. This review examined whether the combination of pharmacological treatments and psychotherapy is associated with higher effectiveness than pharmacotherapy alone via meta-analysis; and identified possible treatment effect modifiers via meta-regression-analysis. Methods A systematic search was conducted in the following databases: Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, ISI Web of Science, BIOSIS, PsycINFO, and CINAHL. Primary efficacy outcome was a response to treatment; primary acceptance outcome was dropping out of the study. Only randomized controlled trials were considered. Results We identified 8 studies with a total of 9 relevant comparisons. Our analysis revealed small, but statistically not significant effects of combined therapies on outcomes directly related to depression (BR = 1.20) with substantial heterogeneity between studies (I² = 67%). Three treatment effect modifiers were identified: target disorders, the type of psychotherapy and the type of pharmacotherapy. Small but statistically significant effects of combined therapies on quality of life (SMD = 0.18) were revealed. No differences in acceptance rates and the long-term effects between combined treatments and pure pharmacological interventions were observed. Conclusions This systematic review could not provide clear evidence for the combination of pharmacotherapy and psychotherapy. However, due to the small amount of primary studies further research is needed for a conclusive decision. PMID:22694751

An overview of meta-analysis for clinicians

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Lee, Young Ho

2018-01-01

The number of medical studies being published is increasing exponentially, and clinicians must routinely process large amounts of new information. Moreover, the results of individual studies are often insufficient to provide confident answers, as their results are not consistently reproducible. A meta-analysis is a statistical method for combining the results of different studies on the same topic and it may resolve conflicts among studies. Meta-analysis is being used increasingly and plays an important role in medical research. This review introduces the basic concepts, steps, advantages, and caveats of meta-analysis, to help clinicians understand it in clinical practice and research. A major advantage of a meta-analysis is that it produces a precise estimate of the effect size, with considerably increased statistical power, which is important when the power of the primary study is limited because of a small sample size. A meta-analysis may yield conclusive results when individual studies are inconclusive. Furthermore, meta-analyses investigate the source of variation and different effects among subgroups. In summary, a meta-analysis is an objective, quantitative method that provides less biased estimates on a specific topic. Understanding how to conduct a meta-analysis aids clinicians in the process of making clinical decisions. PMID:29277096

An overview of meta-analysis for clinicians.

Science.gov (United States)

Lee, Young Ho

2018-03-01

The number of medical studies being published is increasing exponentially, and clinicians must routinely process large amounts of new information. Moreover, the results of individual studies are often insufficient to provide confident answers, as their results are not consistently reproducible. A meta-analysis is a statistical method for combining the results of different studies on the same topic and it may resolve conflicts among studies. Meta-analysis is being used increasingly and plays an important role in medical research. This review introduces the basic concepts, steps, advantages, and caveats of meta-analysis, to help clinicians understand it in clinical practice and research. A major advantage of a meta-analysis is that it produces a precise estimate of the effect size, with considerably increased statistical power, which is important when the power of the primary study is limited because of a small sample size. A meta-analysis may yield conclusive results when individual studies are inconclusive. Furthermore, meta-analyses investigate the source of variation and different effects among subgroups. In summary, a meta-analysis is an objective, quantitative method that provides less biased estimates on a specific topic. Understanding how to conduct a meta-analysis aids clinicians in the process of making clinical decisions.

Combination therapy versus gemcitabine monotherapy in the treatment of elderly pancreatic cancer: a meta-analysis of randomized controlled trials

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Jin JM

2018-03-01

Full Text Available Jiamin Jin, Chunbo Teng, Tao Li College of Life Science, Northeast Forestry University, Harbin, China Purpose: We aimed to compare the efficacy of combination therapy versus gemcitabine monotherapy in the treatment of elderly pancreatic cancer (PC by using a meta-analysis.Materials and methods: Databases were searched to identify relevant clinical trials. Hazard ratios (HRs were used to estimate overall survival (OS and progression-free survival (PFS. Statistical analyses were conducted by using Comprehensive Meta Analysis software (version 2.0.Results: A total of 3,401 elderly PC patients from six randomized controlled trials were included for analysis. In comparison with gemcitabine alone, combination therapy in elderly PC patients did not significantly improve OS (HR 0.93, 95% CI: 0.82–1.06, p=0.29. Sub-group analysis according to treatment regimens showed that combined chemotherapy significantly improved OS in comparison with gemcitabine alone (HR 0.73, 95% CI: 0.56–0.94, p=0.016, while gemcitabine plus targeted agents did not improve OS (HR 1.02, 95% CI: 0.87–1.19, p=0.83. Additionally, gemcitabine plus nab-paclitaxel significantly improved PFS in elderly PC patients (HR 0.69, 95% CI: 0.52–0.91, p=0.009 in comparison with gemcitabine alone. No publication bias was detected by Begg’s and Egger’s tests for OS.Conclusion: The findings of this study suggest that combined chemotherapy, but not for gemcitabine plus targeted agents, could be recommended for elderly PC patients due to its survival benefits. Further studies are still needed to assess the treatment tolerance of combination chemotherapy in these patient populations. Keywords: pancreatic cancer, elderly, randomized controlled trials, meta-analysis, targeted agents

Bayesian meta-analysis models for microarray data: a comparative study

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Song Joon J

2007-03-01

Full Text Available Abstract Background With the growing abundance of microarray data, statistical methods are increasingly needed to integrate results across studies. Two common approaches for meta-analysis of microarrays include either combining gene expression measures across studies or combining summaries such as p-values, probabilities or ranks. Here, we compare two Bayesian meta-analysis models that are analogous to these methods. Results Two Bayesian meta-analysis models for microarray data have recently been introduced. The first model combines standardized gene expression measures across studies into an overall mean, accounting for inter-study variability, while the second combines probabilities of differential expression without combining expression values. Both models produce the gene-specific posterior probability of differential expression, which is the basis for inference. Since the standardized expression integration model includes inter-study variability, it may improve accuracy of results versus the probability integration model. However, due to the small number of studies typical in microarray meta-analyses, the variability between studies is challenging to estimate. The probability integration model eliminates the need to model variability between studies, and thus its implementation is more straightforward. We found in simulations of two and five studies that combining probabilities outperformed combining standardized gene expression measures for three comparison values: the percent of true discovered genes in meta-analysis versus individual studies; the percent of true genes omitted in meta-analysis versus separate studies, and the number of true discovered genes for fixed levels of Bayesian false discovery. We identified similar results when pooling two independent studies of Bacillus subtilis. We assumed that each study was produced from the same microarray platform with only two conditions: a treatment and control, and that the data sets

Combination of EGFR-TKIs and chemotherapy as first-line therapy for advanced NSCLC: a meta-analysis.

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OuYang, Pu-Yun; Su, Zhen; Mao, Yan-Ping; Deng, Wuguo; Xie, Fang-Yun

2013-01-01

The impact of combining epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) and chemotherapy as first-line therapy for patients with advanced non-small-cell lung cancer (NSCLC) remains controversial. Therefore, randomized trials that compared this combined regimen with chemotherapy or EGFR-TKIs monotherapy were included for this meta-analysis. We used published hazard ratios (HRs), if available, or derived treatment estimates from other survival data. Pooled estimates of treatment efficacy of the combined regimen in the entire unselected population and selected patients by EGFR-mutation status and smoking history were calculated. Eight trials eventually entered into this meta-analysis, including 4585 patients. Overall, the combined regimen significantly delayed disease progression (HR = 0.81, 95% CI 0.69-0.95, P = 0.01); subgroup analysis showed significantly higher progression free survival advantages in Asian patients (Pchemotherapy (P = 0.02). In selected patients by EGFR-mutation, both mutation positive (HR = 0.48, 95% CI 0.28-0.83, P = 0.009) and negative (HR = 0.84, 95% CI 0.72-0.98, P = 0.02) patients gained progression free survival benefit from the combined regimen, albeit the magnitude of benefit was marginally larger in mutation positive patients (P = 0.05). In selected patients by smoking history, never/light smokers achieved a great progression free survival benefit from the combined regimen (HR = 0.51, 95% CI 0.35-0.74, P = 0.0004). Unfortunately, the combined regimen had no significant impact on overall survival, irrespective of ethnicity, dose schedules or EGFR-mutation status. Severe anorexia (RR = 2.01, 95% CI 1.11-3.63; P = 0.02) and diarrhea (RR = 2.70, 95% CI 1.94-3.76; Pchemotherapy deserved to be considered in the future, although it is not approved for advanced NSCLC at the moment.

Combinations of techniques that effectively change health behavior : evidence from meta-Cart analysis

NARCIS (Netherlands)

Dusseldorp, E.; Buuren, S. van; Genugten, L. van; Verheijden, M.W.; Empelen, P. van

2014-01-01

Objective: Many health-promoting interventions combine multiple behavior change techniques (BCTs) to maximize effectiveness. Although, in theory, BCTs can amplify each other, the available meta-analyses have not been able to identify specific combinations of techniques that provide synergistic

Development of a combined database for meta-epidemiological research

DEFF Research Database (Denmark)

Savović, Jelena; Harris, Ross J; Wood, Lesley

2010-01-01

or review. Unique identifiers were assigned to each reference and used to identify duplicate trials. Sets of meta-analyses with overlapping trials were identified and duplicates removed. Overlapping trials were used to examine agreement between assessments of trial characteristics. The combined database...... database will be used to examine the combined evidence on sources of bias in randomized controlled trials. The strategy used to remove overlap between meta-analyses may be of use for future empirical research. Copyright © 2010 John Wiley & Sons, Ltd.......Collections of meta-analyses assembled in meta-epidemiological studies are used to study associations of trial characteristics with intervention effect estimates. However, methods and findings are not consistent across studies. To combine data from 10 meta-epidemiological studies into a single...

Meta-analysis with R

CERN Document Server

Schwarzer, Guido; Rücker, Gerta

2015-01-01

This book provides a comprehensive introduction to performing meta-analysis using the statistical software R. It is intended for quantitative researchers and students in the medical and social sciences who wish to learn how to perform meta-analysis with R. As such, the book introduces the key concepts and models used in meta-analysis. It also includes chapters on the following advanced topics: publication bias and small study effects; missing data; multivariate meta-analysis, network meta-analysis; and meta-analysis of diagnostic studies.  .

Is the combination of interval and resistance training more effective on physical fitness? A systematic review and Meta-analysis

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Francisco José de Menezes Júnior

2017-12-01

Full Text Available Interval training (HIIT / SIT combined with resistance training (RT has been highlighted as a strategy for the improvement of health-related physical fitness markers (HRPF in adults. Thus, the aim of this meta-analysis was to compare the efficacy of combined training (HIIT / SIT + RT with other exercise protocols on HRPF markers in adults. A systematic search was performed in MEDLINE via PebMed, Cochrane-CENTRAL, SPORTDiscus, LILACS, SCIELO and Scopus databases between January and March 2017, using the following keywords in English and Portuguese: physical fitness, high-intensity interval training, sprint interval training, resistance training and adults. The quality of studies was evaluated using the PEDro scale. After applying both inclusion and exclusion criteria, nine articles were selected (n = 231. The extraction of means and standard deviations from studies was performed independently by two authors and the RevMan software was used to perform the meta-analysis. Combined training interventions lasted from 6 to 12 weeks and generated greater increase in maximal oxygen uptake than other forms of exercise. The combination of interval training and strength training may be considered more effective to improve aerobic capacity levels in adults.

Rethinking Meta-Analysis: Applications for Air Pollution Data and Beyond

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Goodman, Julie E; Petito Boyce, Catherine; Sax, Sonja N; Beyer, Leslie A; Prueitt, Robyn L

2015-01-01

Meta-analyses offer a rigorous and transparent systematic framework for synthesizing data that can be used for a wide range of research areas, study designs, and data types. Both the outcome of meta-analyses and the meta-analysis process itself can yield useful insights for answering scientific questions and making policy decisions. Development of the National Ambient Air Quality Standards illustrates many potential applications of meta-analysis. These applications demonstrate the strengths and limitations of meta-analysis, issues that arise in various data realms, how meta-analysis design choices can influence interpretation of results, and how meta-analysis can be used to address bias and heterogeneity. Reviewing available data from a meta-analysis perspective can provide a useful framework and impetus for identifying and refining strategies for future research. Moreover, increased pervasiveness of a meta-analysis mindset—focusing on how the pieces of the research puzzle fit together—would benefit scientific research and data syntheses regardless of whether or not a quantitative meta-analysis is undertaken. While an individual meta-analysis can only synthesize studies addressing the same research question, the results of separate meta-analyses can be combined to address a question encompassing multiple data types. This observation applies to any scientific or policy area where information from a variety of disciplines must be considered to address a broader research question. PMID:25969128

Combined application versus topical and intravenous application of tranexamic acid following primary total hip arthroplasty: a meta-analysis.

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Zhang, Pei; Liang, Yuan; Chen, Pengtao; Fang, Yongchao; He, Jinshan; Wang, Jingcheng

2017-02-21

The use of intravenous (IV) or topical tranexamic acid (TXA) in total hip arthroplasty has been proven to be effective and safe in total hip arthroplasty. However, which of these two administration routes is better has not been determined. The combined administration of TXA has been used in total knee arthroplasty with satisfactory results. We hypothesized that combined application of TXA may be the most effective way without increased rate of thrombotic events such as deep vein thrombosis (DVT) and pulmonary embolisms (PE) in patients subjected to primary total hip replacement (THA). A meta-analysis was conducted to compare the efficacy and safety of the combined use of tranexamic acid (TXA) relative to topical or intravenous (IV) use alone for treatment of primary THA. The outcomes included total blood loss, postoperative hemoglobin decline, transfusion rates, and the incidence rates of deep vein thrombosis (DVT) and pulmonary embolisms (PE). We searched electronic databases including PubMed, EMBASE, the Cochrane Library, Web of Science, the Chinese Biomedical Literature database, the CNKI database, and Wanfang Data until September 2016. The references of the included articles were also checked for additional potentially relevant studies. There were no language restrictions for the search. The data of the included studies were analyzed using RevMan 5.3 software. Seven studies met the inclusion criteria, encompassing a total of 1762 patients. Our meta-analysis demonstrated that total blood loss, postoperative hemoglobin decline, and transfusion rates were significantly lower for patients that received the combined treatment compared to patients that received either topical or intravenous administration of TXA. No statistical differences were found in the incidence of deep venous thrombosis (DVT) or pulmonary embolism (PE). The group that received the combined treatment had lower total blood loss, postoperative hemoglobin decline, and transfusion rates without an

Jianpi Bushen, a Traditional Chinese Medicine Therapy, Combined with Chemotherapy for Gastric Cancer Treatment: A Meta-Analysis of Randomized Controlled Trials

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Chen, Yunbo; Zhang, Guijuan; Chen, Xiaoping; Jiang, Xuefeng; Yuan, Naijun; Wang, Yurong; Hao, Xiaoqian

2018-01-01

Objective. To investigate the effects of Jianpi Bushen (JPBS), a traditional Chinese medicine that is used to invigorate the spleen and tonify the kidney, combined with chemotherapy for the treatment of gastric cancer. Methods. Literature retrieval was performed in PubMed, EMBASE, Cochrane Library, MEDLINE, CNKI, Wanfang Data Information Site, and VIP from inception to October 2017. Randomized controlled trials to evaluate the effects of JPBS combined with chemotherapy were identified. The primary reported outcomes were KPS (Karnofsky Performance Status), clinical curative efficiency, immune function, blood system, and nonhematologic system. Review Manager 5.3 (RevMan 5.3) was used for data analysis, and the quality of the studies was also appraised. Results. A total of 26 studies were included with 3098 individuals. The results of the meta-analysis indicated that treatment of gastric cancer with the combination of JPBS and chemotherapy resulted in better outcomes compared to chemotherapy alone. Conclusion. Evidence from the meta-analysis suggested that JPBS combined with chemotherapy has a positive effect on gastric cancer treatment. However, additional rigorously designed and large sample randomized controlled trials are required to confirm the efficacy and safety of this treatment. PMID:29675052

Meta-analysis in plant pathology: synthesizing research results.

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Rosenberg, M S; Garrett, K A; Su, Z; Bowden, R L

2004-09-01

ABSTRACT Meta-analysis is a set of statistical procedures for synthesizing research results from a number of different studies. An estimate of a statistical effect, such as the difference in disease severity for plants with or without a management treatment, is collected from each study along with a measure of the variance of the estimate of the effect. Combining results from different studies will generally result in increased statistical power so that it is easier to detect small effects. Combining results from different studies may also make it possible to compare the size of the effect as a function of other predictor variables such as geographic region or pathogen species. We present a review of the basic methodology for meta-analysis. We also present an example of meta-analysis of the relationship between disease severity and yield loss for foliar wheat diseases, based on data collected from a decade of fungicide and nematicide test results.

A meta-analysis of the combined effect of housing and environmental enrichment characteristics on the behaviour and performance of pigs

NARCIS (Netherlands)

Averos, X.; Brossard, L.; Dourmad, J.Y.; Greef, de K.H.; Edge, H.L.; Edwards, S.A.; Meunier-Salaün, M.C.

2010-01-01

To quantify the combined effect of housing conditions and environmental enrichment on the behaviour and performance of pigs, a meta-analysis was performed using information from 45 experiments in 42 published manuscripts. Multiple regression models were applied to evaluate the effects of space

Meta analysis on clinical effectiveness of Chinese medicine physiotherapy combined with tropicamide eye drops for pseudomyopia

OpenAIRE

Dan Li; Ling Shen; En-Li Deng

2018-01-01

AIM:To evaluate the curative effect of Chinese medicine physiotherapy combined with tropicamide eye drops to treat pseudomyopia in children and adolescent. METHODS: We collected randomized controlled trials from CNKI, CBM, Wanfang database, PubMed, EMBASE and Cochrane Library in 2000-2015, and the improved Jadad scale was used to evaluate the methodology of the literature, and the data was extracted. The Review Manager 5.3 statistical software was used for meta analysis. RESULTS: A total of 5...

Effect of metformin on the prognosis of diabetic patients combined with gynecologic cancer: A Meta-analysis

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Zi-long CHEN

2018-04-01

Full Text Available Objective To systematically evaluate the effect of metformin on the prognosis of diabetic patients combined with gynecologic cancer. Methods The database including PubMed, Embase, CNKI and Wangfang, were electronically searched with no language restriction from their inception to March 2017 to collect the studies about the effect of metformin on the prognosis of diabetic patients combined with gynecologic cancer. The references in reviews were also searched. According to the inclusion and exclusion criteria, two reviewers screened the literatures independently, extracted data and assessed methodological quality by the Newcastle-Ottawa scale. The primary end points included overall survival (OS and progress free survival (PFS. The outcome measures were the pooled hazard ratios (HR and 95% confidence intervals (95% CI. I2 was performed in a heterogeneity assessment. Publication bias was evaluated by using Begg's funnel plot and Egger's test, and the sensitivity analysis was conducted to confirm robustness. The Meta-analysis was performed using STATA 12.0 software. Results Sixteen eligible retrospective cohort studies were included and the score of quality assessment were ranged from 6 to 9. The Meta-analysis showed that metformin could improve the OS of diabetic patients with gynecologic tumors (HR=0.71, 95%CI 0.59-0.85, P=0.000. Subgroup analysis revealed that metformin could improve the OS of diabetic patients combined with endometrial cancer (HR=0.70, 95%CI 0.54-0.89, P=0.004 and diabetic patients combined with cervical cancer (HR=0.95, 95%CI 0.90-1.00, P=0.048. Meanwhile metformin improved the OS (HR=0.56, 95%CI 0.38-0.83, P=0.004 and PFS (HR=0.45, 95%CI 0.30-0.68, P=0.000 of diabetic patients with ovarian cancer after adjusting for confounders. Conclusions The use of metformin is positive for the prognosis of diabetic patients combined with gynecologic cancer. It may improve the OS of diabetic patients with endometrial cancer and diabetic

The use of meta-analysis or research synthesis to combine driving simulation or naturalistic study results on driver distraction.

Science.gov (United States)

Caird, Jeff K; Johnston, Katherine A; Willness, Chelsea R; Asbridge, Mark

2014-06-01

Three important and inter-related topics are addressed in this paper. First, the importance of meta-analysis and research synthesis methods to combine studies on traffic safety, in general, and on driver distraction, in particular, is briefly reviewed. Second, naturalistic, epidemiologic, and driving simulation studies on driver distraction are used to illustrate convergent and divergent results that have accumulated thus far in this domain of research. In particular, mobile phone conversation, passenger presence, and text messaging naturalistic studies use meta-analyses and research syntheses to illustrate important patterns of results that are in need of more in-depth study. Third, a number of driver distraction study limitations such as poorly defined dependent variables, lack of methodological detail, and omission of statistical information prevent the integration of many studies into meta-analyses. In addition, the overall quality of road safety studies suffers from these same limitations and suggestions for improvement are made to guide researchers and reviewers. Practical Applications. The use of research synthesis and meta-analysis provide comprehensive estimates of the impact of distractions on driving performance, which can be used to guide public policy and future research. Copyright © 2014 National Safety Council and Elsevier Ltd. All rights reserved.

The potential for meta-analysis to support decision analysis in ecology.

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Mengersen, Kerrie; MacNeil, M Aaron; Caley, M Julian

2015-06-01

Meta-analysis and decision analysis are underpinned by well-developed methods that are commonly applied to a variety of problems and disciplines. While these two fields have been closely linked in some disciplines such as medicine, comparatively little attention has been paid to the potential benefits of linking them in ecology, despite reasonable expectations that benefits would be derived from doing so. Meta-analysis combines information from multiple studies to provide more accurate parameter estimates and to reduce the uncertainty surrounding them. Decision analysis involves selecting among alternative choices using statistical information that helps to shed light on the uncertainties involved. By linking meta-analysis to decision analysis, improved decisions can be made, with quantification of the costs and benefits of alternate decisions supported by a greater density of information. Here, we briefly review concepts of both meta-analysis and decision analysis, illustrating the natural linkage between them and the benefits from explicitly linking one to the other. We discuss some examples in which this linkage has been exploited in the medical arena and how improvements in precision and reduction of structural uncertainty inherent in a meta-analysis can provide substantive improvements to decision analysis outcomes by reducing uncertainty in expected loss and maximising information from across studies. We then argue that these significant benefits could be translated to ecology, in particular to the problem of making optimal ecological decisions in the face of uncertainty. Copyright © 2013 John Wiley & Sons, Ltd.

MADAM - An open source meta-analysis toolbox for R and Bioconductor

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Graber Armin

2010-03-01

Full Text Available Abstract Background Meta-analysis is a major theme in biomedical research. In the present paper we introduce a package for R and Bioconductor that provides useful tools for performing this type of work. One idea behind the development of MADAM was that many meta-analysis methods, which are available in R, are not able to use the capacities of parallel computing yet. In this first version, we implemented one meta-analysis method in such a parallel manner. Additionally, we provide tools for combining the results from a set of methods in an ensemble approach. Functionality for visualization of results is also provided. Results The presented package enables the carrying out of meta-analysis either by providing functions directly or by wrapping them to existing implementations. Overall, five different meta-analysis methods are now usable through MADAM, along with another three methods for combining the corresponding results. Visualizing the results is eased by three included functions. For developing and testing meta-analysis methods, a mock up data generator is integrated. Conclusions The use of MADAM enables a user to focus on one package, in turn enabling them to work with the same data types across a set of methods. By making use of the snow package, MADAM can be made compatible with an existing parallel computing infrastructure. MADAM is open source and freely available within CRAN http://cran.r-project.org.

Drivers of wetland conversion: a global meta-analysis.

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van Asselen, Sanneke; Verburg, Peter H; Vermaat, Jan E; Janse, Jan H

2013-01-01

Meta-analysis of case studies has become an important tool for synthesizing case study findings in land change. Meta-analyses of deforestation, urbanization, desertification and change in shifting cultivation systems have been published. This present study adds to this literature, with an analysis of the proximate causes and underlying forces of wetland conversion at a global scale using two complementary approaches of systematic review. Firstly, a meta-analysis of 105 case-study papers describing wetland conversion was performed, showing that different combinations of multiple-factor proximate causes, and underlying forces, drive wetland conversion. Agricultural development has been the main proximate cause of wetland conversion, and economic growth and population density are the most frequently identified underlying forces. Secondly, to add a more quantitative component to the study, a logistic meta-regression analysis was performed to estimate the likelihood of wetland conversion worldwide, using globally-consistent biophysical and socioeconomic location factor maps. Significant factors explaining wetland conversion, in order of importance, are market influence, total wetland area (lower conversion probability), mean annual temperature and cropland or built-up area. The regression analyses results support the outcomes of the meta-analysis of the processes of conversion mentioned in the individual case studies. In other meta-analyses of land change, similar factors (e.g., agricultural development, population growth, market/economic factors) are also identified as important causes of various types of land change (e.g., deforestation, desertification). Meta-analysis helps to identify commonalities across the various local case studies and identify which variables may lead to individual cases to behave differently. The meta-regression provides maps indicating the likelihood of wetland conversion worldwide based on the location factors that have determined historic

Quality of Life in Autism across the Lifespan: A Meta-Analysis

Science.gov (United States)

van Heijst, Barbara F. C.; Geurts, Hilde M.

2015-01-01

Autism is a lifelong neurodevelopmental disorder, with a known impact on quality of life. Yet the developmental trajectory of quality of life is not well understood. First, the effect of age on quality of life was studied with a meta-analysis. Our meta-analysis included 10 studies (published between 2004 and 2012) with a combined sample size of…

Meta analysis on clinical effectiveness of Chinese medicine physiotherapy combined with tropicamide eye drops for pseudomyopia

Directory of Open Access Journals (Sweden)

Dan Li

2018-05-01

Full Text Available AIM:To evaluate the curative effect of Chinese medicine physiotherapy combined with tropicamide eye drops to treat pseudomyopia in children and adolescent. METHODS: We collected randomized controlled trials from CNKI, CBM, Wanfang database, PubMed, EMBASE and Cochrane Library in 2000-2015, and the improved Jadad scale was used to evaluate the methodology of the literature, and the data was extracted. The Review Manager 5.3 statistical software was used for meta analysis. RESULTS: A total of 5 articles were included in the analysis, with a total sample size of 836 cases. The curative effect of experimental group on pseudomyopia was better than that of control group, and the differences are statistically significant(Z=6.39, PCONCLUSION: Compared with topiramine eye drops alone, combined with traditional Chinese medicine therapy for treating pseudomyopia in children and adolescent is more effective, and is safe and reliable.

Antibacterial effect of calcium hydroxide combined with chlorhexidine on Enterococcus faecalis: a systematic review and meta-analysis

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Masoud SAATCHI

2014-10-01

Full Text Available Objective: Enterococcus faecalis (E. faecalis is the most frequently isolated strain in failed endodontic therapy cases since it is resistant to calcium hydroxide (CH. Whether a combination of CH and chlorhexidine (CHX is more effective than CH alone against E. faecalis is a matter of controversy. Thus, the aim of this study was to conduct a systematic review and meta-analysis of the literature. Material and Methods: A comprehensive search in PubMed, EMbase, EBSCOhost, The Cochrane Library, SciELO, and BBO databases, Clinical trials registers, Open Grey, and conference proceedings from the earliest available date to February 1, 2013 was carried out and the relevant articles were identified by two independent reviewers. Backward and forward search was performed and then inclusion and exclusion criteria were applied. The included studies were divided into "comparisons" according to the depth of sampling and dressing period of each medicament. Meta-analysis was performed using Stata software 10.0. The level of significance was set at 0.05. Results: Eighty-five studies were retrieved from databases and backward/forward searches. Fortyfive studies were considered as relevant (5 in vivo, 18 in vitro, 18 ex vivo, and 4 review articles. Nine studies were included for meta-analysis. Inter-observer agreement (Cohen kappa was 0.93. The included studies were divided into 21 comparisons for meta-analysis. Chi-square test showed the comparisons were heterogeneous (p<0.001. Random effect model demonstrated no significant difference between CH/CHX mixture and CH alone in their effect on E. faecalis (p=0.115. Conclusions: According to the evidence available now, mixing CH with CHX does not significantly increase the antimicrobial activity of CH against E. faecalis. It appears that mixing CH with CHX does not improve its ex vivo antibacterial property as an intracanal medicament against E. faecalis. Further in vivo studies are necessary to confirm and correlate

Antibacterial effect of calcium hydroxide combined with chlorhexidine on Enterococcus faecalis: a systematic review and meta-analysis

Science.gov (United States)

SAATCHI, Masoud; SHOKRANEH, Ali; NAVAEI, Hooman; MARACY, Mohammad Reza; SHOJAEI, Hasan

2014-01-01

Objective Enterococcus faecalis (E. faecalis) is the most frequently isolated strain in failed endodontic therapy cases since it is resistant to calcium hydroxide (CH). Whether a combination of CH and chlorhexidine (CHX) is more effective than CH alone against E. faecalis is a matter of controversy. Thus, the aim of this study was to conduct a systematic review and meta-analysis of the literature. Material and Methods A comprehensive search in PubMed, EMbase, EBSCOhost, The Cochrane Library, SciELO, and BBO databases, Clinical trials registers, Open Grey, and conference proceedings from the earliest available date to February 1, 2013 was carried out and the relevant articles were identified by two independent reviewers. Backward and forward search was performed and then inclusion and exclusion criteria were applied. The included studies were divided into "comparisons" according to the depth of sampling and dressing period of each medicament. Meta-analysis was performed using Stata software 10.0. The level of significance was set at 0.05. Results Eighty-five studies were retrieved from databases and backward/forward searches. Fortyfive studies were considered as relevant (5 in vivo, 18 in vitro, 18 ex vivo, and 4 review articles). Nine studies were included for meta-analysis. Inter-observer agreement (Cohen kappa) was 0.93. The included studies were divided into 21 comparisons for meta-analysis. Chi-square test showed the comparisons were heterogeneous (p<0.001). Random effect model demonstrated no significant difference between CH/CHX mixture and CH alone in their effect on E. faecalis (p=0.115). Conclusions According to the evidence available now, mixing CH with CHX does not significantly increase the antimicrobial activity of CH against E. faecalis. It appears that mixing CH with CHX does not improve its ex vivo antibacterial property as an intracanal medicament against E. faecalis. Further in vivo studies are necessary to confirm and correlate the findings of

Sufentanil and Bupivacaine Combination versus Bupivacaine Alone for Spinal Anesthesia during Cesarean Delivery: A Meta-Analysis of Randomized Trials

Science.gov (United States)

Yan, Jianqin; Wang, Ruike; Wang, Ying; Xu, Mu

2016-01-01

Objective The addition of lipophilic opioids to local anesthetics for spinal anesthesia has become a widely used strategy for cesarean anesthesia. A meta-analysis to quantify the benefits and risks of combining sufentanil with bupivacaine for patients undergoing cesarean delivery was conducted. Methods A comprehensive literature search without language or date limitation was performed to identify clinical trials that compared the addition of sufentanil to bupivacaine with bupivacaine alone for spinal anesthesia in healthy parturients choosing cesarean delivery. The Q and I2 tests were used to assess heterogeneity of the data. Data from each trial were combined using relative ratios (RRs) for dichotomous data or weighted mean differences (WMDs) for continuous data and corresponding 95% confidence intervals (95% CIs) for each trial. Sensitivity analysis was conducted by removing one study a time to assess the quality and consistency of the results. Begg’s funnel plots and Egger’s linear regression test were used to detect any publication bias. Results This study included 9 trials containing 578 patients in the final meta-analysis. Sufentanil addition provided a better analgesia quality with less breakthrough pain during surgery than bupivacaine alone (RR = 0.10, 95% CI 0.06 to 0.18, P bupivacaine-alone group (WMD = −1.0 min, 95% CI −1.5 to −0.58, P Bupivacaine and sufentanil combination is superior to that of bupivacaine alone for spinal anesthesia for cesarean delivery in analgesia quality. Women receiving the combined two drugs had less breakthrough pain, shorter sensory block onset time, and longer first analgesic request time. However, the addition of sufentanil to bupivacaine increased the incidence of pruritus. PMID:27032092

Longitudinal Meta-analysis

NARCIS (Netherlands)

Hox, J.J.; Maas, C.J.M.; Lensvelt-Mulders, G.J.L.M.

2004-01-01

The goal of meta-analysis is to integrate the research results of a number of studies on a specific topic. Characteristic for meta-analysis is that in general only the summary statistics of the studies are used and not the original data. When the published research results to be integrated

Multivariate Meta-Analysis Using Individual Participant Data

Science.gov (United States)

Riley, R. D.; Price, M. J.; Jackson, D.; Wardle, M.; Gueyffier, F.; Wang, J.; Staessen, J. A.; White, I. R.

2015-01-01

When combining results across related studies, a multivariate meta-analysis allows the joint synthesis of correlated effect estimates from multiple outcomes. Joint synthesis can improve efficiency over separate univariate syntheses, may reduce selective outcome reporting biases, and enables joint inferences across the outcomes. A common issue is…

Living network meta-analysis compared with pairwise meta-analysis in comparative effectiveness research: empirical study

Science.gov (United States)

Nikolakopoulou, Adriani; Mavridis, Dimitris; Furukawa, Toshi A; Cipriani, Andrea; Tricco, Andrea C; Straus, Sharon E; Siontis, George C M; Egger, Matthias

2018-01-01

Abstract Objective To examine whether the continuous updating of networks of prospectively planned randomised controlled trials (RCTs) (“living” network meta-analysis) provides strong evidence against the null hypothesis in comparative effectiveness of medical interventions earlier than the updating of conventional, pairwise meta-analysis. Design Empirical study of the accumulating evidence about the comparative effectiveness of clinical interventions. Data sources Database of network meta-analyses of RCTs identified through searches of Medline, Embase, and the Cochrane Database of Systematic Reviews until 14 April 2015. Eligibility criteria for study selection Network meta-analyses published after January 2012 that compared at least five treatments and included at least 20 RCTs. Clinical experts were asked to identify in each network the treatment comparison of greatest clinical interest. Comparisons were excluded for which direct and indirect evidence disagreed, based on side, or node, splitting test (Pmeta-analysis. The frequency and time to strong evidence was compared against the null hypothesis between pairwise and network meta-analyses. Results 49 comparisons of interest from 44 networks were included; most (n=39, 80%) were between active drugs, mainly from the specialties of cardiology, endocrinology, psychiatry, and rheumatology. 29 comparisons were informed by both direct and indirect evidence (59%), 13 by indirect evidence (27%), and 7 by direct evidence (14%). Both network and pairwise meta-analysis provided strong evidence against the null hypothesis for seven comparisons, but for an additional 10 comparisons only network meta-analysis provided strong evidence against the null hypothesis (P=0.002). The median time to strong evidence against the null hypothesis was 19 years with living network meta-analysis and 23 years with living pairwise meta-analysis (hazard ratio 2.78, 95% confidence interval 1.00 to 7.72, P=0.05). Studies directly comparing

Trial Sequential Analysis in systematic reviews with meta-analysis

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Jørn Wetterslev

2017-03-01

Full Text Available Abstract Background Most meta-analyses in systematic reviews, including Cochrane ones, do not have sufficient statistical power to detect or refute even large intervention effects. This is why a meta-analysis ought to be regarded as an interim analysis on its way towards a required information size. The results of the meta-analyses should relate the total number of randomised participants to the estimated required meta-analytic information size accounting for statistical diversity. When the number of participants and the corresponding number of trials in a meta-analysis are insufficient, the use of the traditional 95% confidence interval or the 5% statistical significance threshold will lead to too many false positive conclusions (type I errors and too many false negative conclusions (type II errors. Methods We developed a methodology for interpreting meta-analysis results, using generally accepted, valid evidence on how to adjust thresholds for significance in randomised clinical trials when the required sample size has not been reached. Results The Lan-DeMets trial sequential monitoring boundaries in Trial Sequential Analysis offer adjusted confidence intervals and restricted thresholds for statistical significance when the diversity-adjusted required information size and the corresponding number of required trials for the meta-analysis have not been reached. Trial Sequential Analysis provides a frequentistic approach to control both type I and type II errors. We define the required information size and the corresponding number of required trials in a meta-analysis and the diversity (D2 measure of heterogeneity. We explain the reasons for using Trial Sequential Analysis of meta-analysis when the actual information size fails to reach the required information size. We present examples drawn from traditional meta-analyses using unadjusted naïve 95% confidence intervals and 5% thresholds for statistical significance. Spurious conclusions in

Meta-analysis of the relationship between psychosocial indexes with mental health

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Ayaub Faizy

2015-09-01

Full Text Available Background: The expansion of studies that done in the demand of effective factors such as social factors on mental health provides the ground work for the combination of these studies. So, this meta-analysis was implemented to determine the summary effect size of the relationship between social indexes and mental health measures Material and Methods: The method used in this study is a Meta-Analysis. To achieve above aim used of quantitative findings from 46 studies, that computed 77 effect sizes from these. The studies that were used in this study collected from databases such as magiran, noormags, Scientific Information Database and proceeding articles that published in the Seminars of college student’s Mental Health. After reviewing the inclusion and exclusion criteria, the correlation effect sizes in selected studies were analyzed with the CMA2 software. In this study, were calculated both random and fixed models, that selected random model, according to the results of the heterogeneity analysis of the Q and I2 factors. Results: The results showed that the combinational effect size of the studies obtained 0.139, after eliminated 10 effect sizes. The combined effect size of studies was calculated low based on Cohen's criteria. Also, the results of heterogeneity analysis indicated that there are moderating variables in the studies. The evidence of this meta-analysis associated with prior theoretical and empirical foundations, indicates the relationship between social support and mental health. Conclusion: According to the results of this meta-analysis for successful mental health programs due to cultural and social issues will be necessary.

Meta-Analysis of Explicit Memory Studies in Populations with Intellectual Disability

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Lifshitz, Hefziba; Shtein, Sarit; Weiss, Izhak; Vakil, Eli

2011-01-01

This meta-analysis combines the effect size (ES) of 40 explicit memory experiments in populations with intellectual disability (ID). Eight meta-analyses were performed, as well as contrast tests between ES. The explicit memory of participants with ID was inferior to that of participants with typical development (TD). Relatively preserved explicit…

Efficacy of lamivudine and thymosin alpha-1 combination therapy in treatment of HBeAg-positive chronic hepatitis B: a meta-analysis

Directory of Open Access Journals (Sweden)

QI Youtao

2014-07-01

Full Text Available ObjectiveTo evaluate the efficacy of lamivudine and thymosin alpha-1 combination therapy in the treatment of HBeAg-positive chronic hepatitis B (CHB by meta-analysis. MethodsRandomized controlled trials (RCTs of lamivudine and thymosin alpha-1 combination therapy in treatment of HBeAg-positive CHB (follow-up for at least 24 weeks, from January 1998 to date, were identified by searching Cochrane Library, PubMed, EMBASE, EBSCO, CNKI, Wanfang Data, and CQVIP. Lamivudine monotherapy RCTs were searched for in the same way as control tests. Efficacy was measured by odds ratio. Meta-analysis was carried out with RevMan 5.2 software. ResultsNine RCTs involving 600 patients were included, with 320 cases in the combination therapy group and 280 in the control group. At the end of follow-up, the combination therapy group had significantly higher serum ALT recovery rate, HBV-DNA negative conversion rate, HBeAg negative conversion rate, and HBeAg seroconversion rate than the control group (P＜0.01 for all, with pooled odds ratios (95% confidence intervals of 4.84 (3.28, 7.16, 2.09 (1.45, 3.01, 5.32 (3.35, 8.46, and 6.22 (3.78, 10.25, respectively. ConclusionLamivudine and thymosin alpha-1 combination therapy is more likely to achieve sustained response rate than lamivudine monotherapy for HBeAg-positive CHB. More RCTs of high quality and large scale are required to verify this conclusion．

Transcatheter arterial chemoembolization in combination with radiotherapy for unresectable hepatocellular carcinoma: A systematic review and meta-analysis

International Nuclear Information System (INIS)

Meng Maobin; Cui Yaoli; Lu You; She Bin; Chen Yan; Guan Yongsong; Zhang Ruiming

2009-01-01

Background and Purpose: To evaluate the efficacy and safety of transcatheter arterial chemoembolization (TACE) plus radiotherapy (RT) for unresectable hepatocellular carcinoma (UHCC) using meta-analysis of data from the literature involving available randomized controlled trials of TACE in combination with RT compared with that of TACE alone (Therapy I versus II) in treating UHCC. Material and Methods: We searched the Cochrane Library, MEDLINE, CENTRAL, EMBASE, CBMdisc, and CNKI as well as employing manual searches. Meta-analysis was performed on the results of homogeneous studies. Analyses subdivided by study design were also performed. Results: We found 17 trials involving 1476 patients. 5 of total were Randomized Controlled Trials (RCTs) and 12 were Non-randomized Controlled Clinical Trials (CCTs). In terms of quality, 5 RCTs were graded B, and 12 CCTs were graded C. Our results showed that Therapy I, compared with Therapy II, significantly improved the survival and the tumor response of patients, and was thus more therapeutically beneficial. Serious adverse events were not increased exception for total bilirubin (TB) level. Conclusions: Therapy I was more therapeutically beneficial. However, considering the strength of the evidence, additional randomized controlled trials are needed before Therapy I can be recommended routinely.

Improved score statistics for meta-analysis in single-variant and gene-level association studies.

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Yang, Jingjing; Chen, Sai; Abecasis, Gonçalo

2018-06-01

Meta-analysis is now an essential tool for genetic association studies, allowing them to combine large studies and greatly accelerating the pace of genetic discovery. Although the standard meta-analysis methods perform equivalently as the more cumbersome joint analysis under ideal settings, they result in substantial power loss under unbalanced settings with various case-control ratios. Here, we investigate the power loss problem by the standard meta-analysis methods for unbalanced studies, and further propose novel meta-analysis methods performing equivalently to the joint analysis under both balanced and unbalanced settings. We derive improved meta-score-statistics that can accurately approximate the joint-score-statistics with combined individual-level data, for both linear and logistic regression models, with and without covariates. In addition, we propose a novel approach to adjust for population stratification by correcting for known population structures through minor allele frequencies. In the simulated gene-level association studies under unbalanced settings, our method recovered up to 85% power loss caused by the standard methods. We further showed the power gain of our methods in gene-level tests with 26 unbalanced studies of age-related macular degeneration . In addition, we took the meta-analysis of three unbalanced studies of type 2 diabetes as an example to discuss the challenges of meta-analyzing multi-ethnic samples. In summary, our improved meta-score-statistics with corrections for population stratification can be used to construct both single-variant and gene-level association studies, providing a useful framework for ensuring well-powered, convenient, cross-study analyses. © 2018 WILEY PERIODICALS, INC.

Cognitive-Behavioural Analysis System of Psychotherapy (CBASP), a drug, or their combination: differential therapeutics for persistent depressive disorder: a study protocol of an individual participant data network meta-analysis

Science.gov (United States)

Schramm, Elisabeth; Weitz, Erica S; Salanti, Georgia; Efthimiou, Orestis; Michalak, Johannes; Watanabe, Norio; Keller, Martin B; Kocsis, James H; Klein, Daniel N; Cuijpers, Pim

2016-01-01

Introduction Despite important advances in psychological and pharmacological treatments of persistent depressive disorders in the past decades, their responses remain typically slow and poor, and differential responses among different modalities of treatments or their combinations are not well understood. Cognitive-Behavioural Analysis System of Psychotherapy (CBASP) is the only psychotherapy that has been specifically designed for chronic depression and has been examined in an increasing number of trials against medications, alone or in combination. When several treatment alternatives are available for a certain condition, network meta-analysis (NMA) provides a powerful tool to examine their relative efficacy by combining all direct and indirect comparisons. Individual participant data (IPD) meta-analysis enables exploration of impacts of individual characteristics that lead to a differentiated approach matching treatments to specific subgroups of patients. Methods and analysis We will search for all randomised controlled trials that compared CBASP, pharmacotherapy or their combination, in the treatment of patients with persistent depressive disorder, in Cochrane CENTRAL, PUBMED, SCOPUS and PsycINFO, supplemented by personal contacts. Individual participant data will be sought from the principal investigators of all the identified trials. Our primary outcomes are depression severity as measured on a continuous observer-rated scale for depression, and dropouts for any reason as a proxy measure of overall treatment acceptability. We will conduct a one-step IPD-NMA to compare CBASP, medications and their combinations, and also carry out a meta-regression to identify their prognostic factors and effect moderators. The model will be fitted in OpenBUGS, using vague priors for all location parameters. For the heterogeneity we will use a half-normal prior on the SD. Ethics and dissemination This study requires no ethical approval. We will publish the findings in a peer

The prognostic value of HPV combined p16 status in patients with anal squamous cell carcinoma: a meta-analysis.

Science.gov (United States)

Sun, Guorui; Dong, Xiaoyuan; Tang, Xiaolong; Qu, Hui; Zhang, Hao; Zhao, Ensheng

2018-01-30

Human papillomavirus (HPV) DNA and p16 expression have been identified to be related to the progression of anal squamous cell carcinoma (ASCC). However, the prognostic relevance of combined detection, particularly HPV-/p16+ and HPV+/p16- signatures, is unknown. A meta-analysis of epidemiologic studies was therefore conducted to address this issue. Data were collected from studies comparing overall survival (OS) and disease-free survival (DFS) / disease-specific survival (DSS) / relapse-free survival (RFS) / progression-free survival (PFS) in ASCC patients with HPV and p16 status. The electronic databases of MEDLINE and EMBASE were searched from their inception till 31 May 2017. Study-specific risk estimates were pooled using a fixed-effects model for OS and DFS/DSS/RFS/PFS. Four studies involving a total of 398 ASCC cases were included in this meta-analysis. The pooled results showed that HPV+/p16+ cancers were significantly associated with improved OS (HR = 0.30, 95% CI: 0.17-0.51) and DFS/DSS/RFS/PFS (HR = 0.23, 95% CI: 0.14-0.36). However, patients with HPV-/p16+ or HPV+/p16- do not have a comparably good prognosis compared with HPV+/p16+ patients. The meta-analysis indicated that concomitant detection of HPV-DNA and p16 expression may be of prognostic or therapeutic utility in the evaluation of factors contributing to ASCC. Testing tumor specimens for HPV-DNA and p16 expression might indirectly affect treatment decisions.

Positive effects of combined cognitive and physical exercise training on cognitive function in older adults with mild cognitive impairment or dementia : A meta-analysis

NARCIS (Netherlands)

Karssemeijer, Esther G. A.; Aaronson, Justine A.; Bossers, Willem J.; Smits, Tara; Rikkert, Marcel G. M. Olde; Kessels, Roy P. C.

Combined cognitive and physical exercise interventions have potential to elicit cognitive benefits in older adults with mild cognitive impairment (MCI) or dementia. This meta-analysis aims to quantify the overall effect of these interventions on global cognitive functioning in older adults with MCI

Positive effects of combined cognitive and physical exercise training on cognitive function in older adults with mild cognitive impairment or dementia : A meta-analysis

NARCIS (Netherlands)

Karssemeijer, Esther G. A.; Aaronson, Justine A.; Bossers, Willem J.; Smits, Tara; Rikkert, Marcel G. M. Olde; Kessels, Roy P. C.

2017-01-01

Combined cognitive and physical exercise interventions have potential to elicit cognitive benefits in older adults with mild cognitive impairment (MCI) or dementia. This meta-analysis aims to quantify the overall effect of these interventions on global cognitive functioning in older adults with MCI

Systematic review and meta-analysis: tools for the information age.

Science.gov (United States)

Weatherall, Mark

2017-11-01

The amount of available biomedical information is vast and growing. Natural limitations of the way clinicians and researchers approach this treasure trove of information comprise difficulties locating the information, and once located, cognitive biases may lead to inappropriate use of the information. Systematic reviews and meta-analyses represent important tools in the information age to improve knowledge and action. Systematic reviews represent a census approach to identifying literature to avoid non-response bias. They are a necessary prelude to producing combined quantitative summaries of associations or treatment effects. Meta-analysis comprises the arithmetical techniques for producing combined summaries from individual study reports. Careful, thoughtful and rigorous use of these tools is likely to enhance knowledge and action. Use of standard guidelines, such as the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, or embedding these activities within collaborative groups such as the Cochrane Collaboration, are likely to lead to more useful systematic review and meta-analysis reporting. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Conducting Meta-Analysis Using SAS

CERN Document Server

Arthur, Winfried; Huffcutt, Allen I; Arthur, Winfred

2001-01-01

Conducting Meta-Analysis Using SAS reviews the meta-analysis statistical procedure and shows the reader how to conduct one using SAS. It presents and illustrates the use of the PROC MEANS procedure in SAS to perform the data computations called for by the two most commonly used meta-analytic procedures, the Hunter & Schmidt and Glassian approaches. This book serves as both an operational guide and user's manual by describing and explaining the meta-analysis procedures and then presenting the appropriate SAS program code for computing the pertinent statistics. The practical, step-by-step instru

Systematic review, meta-analysis, and meta-regression: Successful second-line treatment for Helicobacter pylori.

Science.gov (United States)

Muñoz, Neus; Sánchez-Delgado, Jordi; Baylina, Mireia; Puig, Ignasi; López-Góngora, Sheila; Suarez, David; Calvet, Xavier

2018-06-01

Multiple Helicobacter pylori second-line schedules have been described as potentially useful. It remains unclear, however, which are the best combinations, and which features of second-line treatments are related to better cure rates. The aim of this study was to determine that second-line treatments achieved excellent (>90%) cure rates by performing a systematic review and when possible a meta-analysis. A meta-regression was planned to determine the characteristics of treatments achieving excellent cure rates. A systematic review for studies evaluating second-line Helicobacter pylori treatment was carried out in multiple databases. A formal meta-analysis was performed when an adequate number of comparative studies was found, using RevMan5.3. A meta-regression for evaluating factors predicting cure rates >90% was performed using Stata Statistical Software. The systematic review identified 115 eligible studies, including 203 evaluable treatment arms. The results were extremely heterogeneous, with 61 treatment arms (30%) achieving optimal (>90%) cure rates. The meta-analysis favored quadruple therapies over triple (83.2% vs 76.1%, OR: 0.59:0.38-0.93; P = .02) and 14-day quadruple treatments over 7-day treatments (91.2% vs 81.5%, OR; 95% CI: 0.42:0.24-0.73; P = .002), although the differences were significant only in the per-protocol analysis. The meta-regression did not find any particular characteristics of the studies to be associated with excellent cure rates. Second-line Helicobacter pylori treatments achieving>90% cure rates are extremely heterogeneous. Quadruple therapy and 14-day treatments seem better than triple therapies and 7-day ones. No single characteristic of the treatments was related to excellent cure rates. Future approaches suitable for infectious diseases-thus considering antibiotic resistances-are needed to design rescue treatments that consistently achieve excellent cure rates. © 2018 John Wiley & Sons Ltd.

A meta-analysis comparing tenotomy and tenodesis for treating rotator cuff tears combined with long head of the biceps tendon lesions.

Directory of Open Access Journals (Sweden)

Xiliang Shang

Full Text Available The purpose of this meta-analysis was to assess whether there were differences in the outcomes between tenotomy and tenodesis in treating LHBT lesions combined with rotator cuff repairs.Using Medline, Embase, and Cochrane, we searched for articles comparing tenotomy and tenodesis combined with rotator cuff repair which were published before April 2016 with the terms "biceps", "tenotomy", "tenodesis", and "rotator cuff". The controlled clinical studies that met the inclusion and exclusion criteria were assessed for quality of methodology by utilizing the Coleman score.On the basis of the inclusion and exclusion criteria, ten articles (903 patients were included in this meta-analysis. The Coleman score ranged between 40 and 89 in the included studies. The results showed that the incidence of the popeye sign (OR, 2.777, P = 0.000 were higher in tenotomy group compared with tenodesis group when concomitant rotator cuff repair. Statistically significant difference in favor of tenodesis was observed for Constant score (SMD, -0.230, P = 0.025. As for the arm cramping pain, patient satisfaction, VAS score, ASES score and UCLA increased score, the strength and the range of motion, there were no significant differences between tenodesis and tenotomy of the LHBT, corresponding to the currently available results in the literature.Based on this meta-analysis, both tenotomy and tenodesis are effective in pain relief and function improvement in patients with repairable rotator cuff tears. No significant differences in post-operative functional outcome between tenotomy and tenodesis for the treatment of LHBT lesions were observed except for a lower Constant score and higher risk of Popeye deformity in tenotomy.

Meta-analysis: Problems with Russian Publications.

Science.gov (United States)

Verbitskaya, E V

2015-01-01

Meta-analysis is a powerful tool to identify Evidence Based medical technologies (interventions) for use in every day practice. Meta-analysis uses statistical approaches to combine results from multiple studies in an effort to increase power (over individual studies), improve estimates of the size of the effect and/or to resolve uncertainty when reports disagree. Meta-analysis is a quantitative, formal study design used to systematically assess previous research studies to derive conclusions from this research. Meta-analysis may provide more precise estimate of the effect of treatment or risk factor for a disease, or other outcomes, than any individual study contributing to the pooled analysis.We have quite a substantial number of Russian medical publications, but not so many Meta-Analyses published in Russian. Russian publications are cited in English language papers not so often. A total of 90% of clinical studies included in published Meta-Analyses incorporate only English language papers. International studies or papers with Russian co-authors are published in English language. The main question is: what is the problem with inclusion of Russian medical publications in Meta-Analysis? The main reasons for this are the following: 1) It is difficult to find Russian papers, difficult to work with them and to work with Russian journals:a. There are single Russian Biomedical Journals, which are translated into English and are included in databases (PubMed, Scopus and other), despite the fact that all of them have English language abstracts.b. The majority the meta-analyses authors use in their work different citation management software such as the Mendeley, Reference Manager, ProCite, EndNote, and others. These citation management systems allow scientists to organize their own literature databases with internet searches and have adds-on for the Office programs what makes process of literature citation very convenient. The Internet sites of the majority of

Causal Meta-Analysis : Methodology and Applications

NARCIS (Netherlands)

Bax, L.J.

2009-01-01

Meta-analysis is a statistical method to summarize research data from multiple studies in a quantitative manner. This dissertation addresses a number of methodological topics in causal meta-analysis and reports the development and validation of meta-analysis software. In the first (methodological)

Meta-analysis a structural equation modeling approach

CERN Document Server

Cheung, Mike W-L

2015-01-01

Presents a novel approach to conducting meta-analysis using structural equation modeling. Structural equation modeling (SEM) and meta-analysis are two powerful statistical methods in the educational, social, behavioral, and medical sciences. They are often treated as two unrelated topics in the literature. This book presents a unified framework on analyzing meta-analytic data within the SEM framework, and illustrates how to conduct meta-analysis using the metaSEM package in the R statistical environment. Meta-Analysis: A Structural Equation Modeling Approach begins by introducing the impo

Living network meta-analysis compared with pairwise meta-analysis in comparative effectiveness research: empirical study.

Science.gov (United States)

Nikolakopoulou, Adriani; Mavridis, Dimitris; Furukawa, Toshi A; Cipriani, Andrea; Tricco, Andrea C; Straus, Sharon E; Siontis, George C M; Egger, Matthias; Salanti, Georgia

2018-02-28

To examine whether the continuous updating of networks of prospectively planned randomised controlled trials (RCTs) ("living" network meta-analysis) provides strong evidence against the null hypothesis in comparative effectiveness of medical interventions earlier than the updating of conventional, pairwise meta-analysis. Empirical study of the accumulating evidence about the comparative effectiveness of clinical interventions. Database of network meta-analyses of RCTs identified through searches of Medline, Embase, and the Cochrane Database of Systematic Reviews until 14 April 2015. Network meta-analyses published after January 2012 that compared at least five treatments and included at least 20 RCTs. Clinical experts were asked to identify in each network the treatment comparison of greatest clinical interest. Comparisons were excluded for which direct and indirect evidence disagreed, based on side, or node, splitting test (Pmeta-analyses were performed for each selected comparison. Monitoring boundaries of statistical significance were constructed and the evidence against the null hypothesis was considered to be strong when the monitoring boundaries were crossed. A significance level was defined as α=5%, power of 90% (β=10%), and an anticipated treatment effect to detect equal to the final estimate from the network meta-analysis. The frequency and time to strong evidence was compared against the null hypothesis between pairwise and network meta-analyses. 49 comparisons of interest from 44 networks were included; most (n=39, 80%) were between active drugs, mainly from the specialties of cardiology, endocrinology, psychiatry, and rheumatology. 29 comparisons were informed by both direct and indirect evidence (59%), 13 by indirect evidence (27%), and 7 by direct evidence (14%). Both network and pairwise meta-analysis provided strong evidence against the null hypothesis for seven comparisons, but for an additional 10 comparisons only network meta-analysis provided

MetaMeta: integrating metagenome analysis tools to improve taxonomic profiling.

Science.gov (United States)

Piro, Vitor C; Matschkowski, Marcel; Renard, Bernhard Y

2017-08-14

Many metagenome analysis tools are presently available to classify sequences and profile environmental samples. In particular, taxonomic profiling and binning methods are commonly used for such tasks. Tools available among these two categories make use of several techniques, e.g., read mapping, k-mer alignment, and composition analysis. Variations on the construction of the corresponding reference sequence databases are also common. In addition, different tools provide good results in different datasets and configurations. All this variation creates a complicated scenario to researchers to decide which methods to use. Installation, configuration and execution can also be difficult especially when dealing with multiple datasets and tools. We propose MetaMeta: a pipeline to execute and integrate results from metagenome analysis tools. MetaMeta provides an easy workflow to run multiple tools with multiple samples, producing a single enhanced output profile for each sample. MetaMeta includes a database generation, pre-processing, execution, and integration steps, allowing easy execution and parallelization. The integration relies on the co-occurrence of organisms from different methods as the main feature to improve community profiling while accounting for differences in their databases. In a controlled case with simulated and real data, we show that the integrated profiles of MetaMeta overcome the best single profile. Using the same input data, it provides more sensitive and reliable results with the presence of each organism being supported by several methods. MetaMeta uses Snakemake and has six pre-configured tools, all available at BioConda channel for easy installation (conda install -c bioconda metameta). The MetaMeta pipeline is open-source and can be downloaded at: https://gitlab.com/rki_bioinformatics .

MetaComp: comprehensive analysis software for comparative meta-omics including comparative metagenomics.

Science.gov (United States)

Zhai, Peng; Yang, Longshu; Guo, Xiao; Wang, Zhe; Guo, Jiangtao; Wang, Xiaoqi; Zhu, Huaiqiu

2017-10-02

During the past decade, the development of high throughput nucleic sequencing and mass spectrometry analysis techniques have enabled the characterization of microbial communities through metagenomics, metatranscriptomics, metaproteomics and metabolomics data. To reveal the diversity of microbial communities and interactions between living conditions and microbes, it is necessary to introduce comparative analysis based upon integration of all four types of data mentioned above. Comparative meta-omics, especially comparative metageomics, has been established as a routine process to highlight the significant differences in taxon composition and functional gene abundance among microbiota samples. Meanwhile, biologists are increasingly concerning about the correlations between meta-omics features and environmental factors, which may further decipher the adaptation strategy of a microbial community. We developed a graphical comprehensive analysis software named MetaComp comprising a series of statistical analysis approaches with visualized results for metagenomics and other meta-omics data comparison. This software is capable to read files generated by a variety of upstream programs. After data loading, analyses such as multivariate statistics, hypothesis testing of two-sample, multi-sample as well as two-group sample and a novel function-regression analysis of environmental factors are offered. Here, regression analysis regards meta-omic features as independent variable and environmental factors as dependent variables. Moreover, MetaComp is capable to automatically choose an appropriate two-group sample test based upon the traits of input abundance profiles. We further evaluate the performance of its choice, and exhibit applications for metagenomics, metaproteomics and metabolomics samples. MetaComp, an integrative software capable for applying to all meta-omics data, originally distills the influence of living environment on microbial community by regression analysis

A Meta-Analysis of Arsenic Trioxide Combined with Transcatheter Arterial Chemoembolization for Treatment of Primary Hepatic Carcinoma

Directory of Open Access Journals (Sweden)

Ling He

2016-01-01

Full Text Available Primary hepatic carcinoma (PHC is one of the most common malignant tumours in the world. More and more research has shown that As2O3 combined with TACE has a good curative effect in treating PHC. The objectives of this study were to evaluate the therapeutic efficacy and safety of As2O3 combined with TACE in treating PHC. The CNKI, VIP, Wanfang, PubMed, and Cochrane databases were searched from their inception until December 2015. Randomized controlled trials (RCTs comparing As2O3 combined with TACE versus TACE alone in treating PHC were identified. Stata SE 12.0 was used for data analysis. 17 RCTs with 1055 patients were included. Meta-analysis showed that, compared with TACE alone, As2O3 combined with TACE showed significant effects in improving the clinical efficacy rate (P<0.01, decreasing the value of alpha-fetoprotein (P<0.01, increasing the one-year survival rate (P<0.01, and improving the quality of life of PHC patients (P<0.01. Fifteen studies had mentioned adverse events, but no serious adverse effects were reported in any of the included trials. In conclusion, As2O3 combined with TACE therapy appears to be potentially effective in treating PHC and is generally safe. However, further studies with rigorous designs trials and multiregional cooperation trials are needed.

Meta-analysis of randomized clinical trials in the era of individual patient data sharing.

Science.gov (United States)

Kawahara, Takuya; Fukuda, Musashi; Oba, Koji; Sakamoto, Junichi; Buyse, Marc

2018-06-01

Individual patient data (IPD) meta-analysis is considered to be a gold standard when the results of several randomized trials are combined. Recent initiatives on sharing IPD from clinical trials offer unprecedented opportunities for using such data in IPD meta-analyses. First, we discuss the evidence generated and the benefits obtained by a long-established prospective IPD meta-analysis in early breast cancer. Next, we discuss a data-sharing system that has been adopted by several pharmaceutical sponsors. We review a number of retrospective IPD meta-analyses that have already been proposed using this data-sharing system. Finally, we discuss the role of data sharing in IPD meta-analysis in the future. Treatment effects can be more reliably estimated in both types of IPD meta-analyses than with summary statistics extracted from published papers. Specifically, with rich covariate information available on each patient, prognostic and predictive factors can be identified or confirmed. Also, when several endpoints are available, surrogate endpoints can be assessed statistically. Although there are difficulties in conducting, analyzing, and interpreting retrospective IPD meta-analysis utilizing the currently available data-sharing systems, data sharing will play an important role in IPD meta-analysis in the future.

Spatial Bayesian latent factor regression modeling of coordinate-based meta-analysis data.

Science.gov (United States)

Montagna, Silvia; Wager, Tor; Barrett, Lisa Feldman; Johnson, Timothy D; Nichols, Thomas E

2018-03-01

Now over 20 years old, functional MRI (fMRI) has a large and growing literature that is best synthesised with meta-analytic tools. As most authors do not share image data, only the peak activation coordinates (foci) reported in the article are available for Coordinate-Based Meta-Analysis (CBMA). Neuroimaging meta-analysis is used to (i) identify areas of consistent activation; and (ii) build a predictive model of task type or cognitive process for new studies (reverse inference). To simultaneously address these aims, we propose a Bayesian point process hierarchical model for CBMA. We model the foci from each study as a doubly stochastic Poisson process, where the study-specific log intensity function is characterized as a linear combination of a high-dimensional basis set. A sparse representation of the intensities is guaranteed through latent factor modeling of the basis coefficients. Within our framework, it is also possible to account for the effect of study-level covariates (meta-regression), significantly expanding the capabilities of the current neuroimaging meta-analysis methods available. We apply our methodology to synthetic data and neuroimaging meta-analysis datasets. © 2017, The International Biometric Society.

Spatial Bayesian Latent Factor Regression Modeling of Coordinate-based Meta-analysis Data

Science.gov (United States)

Montagna, Silvia; Wager, Tor; Barrett, Lisa Feldman; Johnson, Timothy D.; Nichols, Thomas E.

2017-01-01

Summary Now over 20 years old, functional MRI (fMRI) has a large and growing literature that is best synthesised with meta-analytic tools. As most authors do not share image data, only the peak activation coordinates (foci) reported in the paper are available for Coordinate-Based Meta-Analysis (CBMA). Neuroimaging meta-analysis is used to 1) identify areas of consistent activation; and 2) build a predictive model of task type or cognitive process for new studies (reverse inference). To simultaneously address these aims, we propose a Bayesian point process hierarchical model for CBMA. We model the foci from each study as a doubly stochastic Poisson process, where the study-specific log intensity function is characterised as a linear combination of a high-dimensional basis set. A sparse representation of the intensities is guaranteed through latent factor modeling of the basis coefficients. Within our framework, it is also possible to account for the effect of study-level covariates (meta-regression), significantly expanding the capabilities of the current neuroimaging meta-analysis methods available. We apply our methodology to synthetic data and neuroimaging meta-analysis datasets. PMID:28498564

Grain yield increase in cereal variety mixtures: A meta-analysis of field trials

DEFF Research Database (Denmark)

Kiær, Lars Pødenphant; Skovgaard, Ib; Østergård, Hanne

2009-01-01

on grain yield. To investigate the prevalence and preconditions for positive mixing effects, reported grain yields of variety mixtures and pure variety stands were obtained from previously published variety trials, converted into relative mixing effects and combined using meta-analysis. Furthermore...... as meeting the criteria for inclusion in the meta-analysis; on the other hand, nearly 200 studies were discarded. The accepted studies reported results on both winter and spring types of each crop species. Relative mixing effects ranged from 30% to 100% with an overall meta-estimate of at least 2.7% (p

Meta-Analysis of Effect Sizes Reported at Multiple Time Points Using General Linear Mixed Model

Science.gov (United States)

Musekiwa, Alfred; Manda, Samuel O. M.; Mwambi, Henry G.; Chen, Ding-Geng

2016-01-01

Meta-analysis of longitudinal studies combines effect sizes measured at pre-determined time points. The most common approach involves performing separate univariate meta-analyses at individual time points. This simplistic approach ignores dependence between longitudinal effect sizes, which might result in less precise parameter estimates. In this paper, we show how to conduct a meta-analysis of longitudinal effect sizes where we contrast different covariance structures for dependence between effect sizes, both within and between studies. We propose new combinations of covariance structures for the dependence between effect size and utilize a practical example involving meta-analysis of 17 trials comparing postoperative treatments for a type of cancer, where survival is measured at 6, 12, 18 and 24 months post randomization. Although the results from this particular data set show the benefit of accounting for within-study serial correlation between effect sizes, simulations are required to confirm these results. PMID:27798661

OHBM 2017: Practical intensity based meta-analysis

OpenAIRE

Maumet, Camille

2017-01-01

"Practical intensity-based meta-analysis" slides from my talk in the OHBM 2017 educational talk on Neuroimaging meta-analysis.http://www.humanbrainmapping.org/files/2017/ED Courses/Neuroimaging Meta-Analysis.pdf

Systematic Review and Meta-Analysis of the Efficacy and Safety of Combined Epinephrine and Corticosteroid Therapy for Acute Bronchiolitis in Infants

Directory of Open Access Journals (Sweden)

Kok P. Kua

2017-06-01

Full Text Available Objective: To evaluate the effectiveness of combined epinephrine and corticosteroid therapy for acute bronchiolitis in infants.Methods: Four electronic databases (MEDLINE, EMBASE, CINAHL, and CENTRAL were searched from their inception to February 28, 2017 for studies involving infants aged less than 24 months with bronchiolitis which assessed the use of epinephrine and corticosteroid combination therapy. The methodological quality of the included studies was assessed using the Cochrane Collaboration's Risk of Bias Tool. A random-effects meta-analysis was used to pool the effect estimates. The primary outcomes were hospital admission rate and length of hospital stay.Results: Of 1,489 citations identified, 5 randomized controlled trials involving 1,157 patients were included. All studies were of high quality and low risk of bias. Results of the meta-analysis showed no significant differences in the primary outcomes. Hospitalization rate was reduced by combinatorial therapy of epinephrine and corticosteroid in only one out of five studies, whereas pooled data indicated no benefit over epinephrine plus placebo. Clinical severity scores were significantly improved in all five RCTs when assessed individually, but no benefit was observed compared to epinephrine monotherapy when the data were pooled together. Pooled data showed that combination therapy was more effective at improving oxygen saturation level (mean difference: −0.70; 95% confidence interval: −1.17 to −0.22, p = 0.004. There was no difference in the risk of serious adverse events in infants treated with the combined epinephrine and corticosteroid therapy.Conclusions: Combination treatment of epinephrine and dexamethasone was ineffective in reducing hospital admission and length of stay among infants with bronchiolitis.

Comprehensive School Reform and Achievement: A Meta-Analysis

Science.gov (United States)

Borman, Geoffrey D.; Hewes, Gina M.; Overman, Laura T.; Brown, Shelly

2003-01-01

This meta-analysis reviews research on the achievement effects of comprehensive school reform (CSR) and summarizes the specific effects of 29 widely implemented models. There are limitations on the overall quantity and quality of the research base, but the overall effects of CSR appear promising. The combined quantity, quality, and statistical…

Introduction, comparison, and validation of Meta-Essentials: A free and simple tool for meta-analysis.

Science.gov (United States)

Suurmond, Robert; van Rhee, Henk; Hak, Tony

2017-12-01

We present a new tool for meta-analysis, Meta-Essentials, which is free of charge and easy to use. In this paper, we introduce the tool and compare its features to other tools for meta-analysis. We also provide detailed information on the validation of the tool. Although free of charge and simple, Meta-Essentials automatically calculates effect sizes from a wide range of statistics and can be used for a wide range of meta-analysis applications, including subgroup analysis, moderator analysis, and publication bias analyses. The confidence interval of the overall effect is automatically based on the Knapp-Hartung adjustment of the DerSimonian-Laird estimator. However, more advanced meta-analysis methods such as meta-analytical structural equation modelling and meta-regression with multiple covariates are not available. In summary, Meta-Essentials may prove a valuable resource for meta-analysts, including researchers, teachers, and students. © 2017 The Authors. Research Synthesis Methods published by John Wiley & Sons Ltd.

Combining evidence from multiple electronic health care databases: performances of one-stage and two-stage meta-analysis in matched case-control studies.

Science.gov (United States)

La Gamba, Fabiola; Corrao, Giovanni; Romio, Silvana; Sturkenboom, Miriam; Trifirò, Gianluca; Schink, Tania; de Ridder, Maria

2017-10-01

Clustering of patients in databases is usually ignored in one-stage meta-analysis of multi-database studies using matched case-control data. The aim of this study was to compare bias and efficiency of such a one-stage meta-analysis with a two-stage meta-analysis. First, we compared the approaches by generating matched case-control data under 5 simulated scenarios, built by varying: (1) the exposure-outcome association; (2) its variability among databases; (3) the confounding strength of one covariate on this association; (4) its variability; and (5) the (heterogeneous) confounding strength of two covariates. Second, we made the same comparison using empirical data from the ARITMO project, a multiple database study investigating the risk of ventricular arrhythmia following the use of medications with arrhythmogenic potential. In our study, we specifically investigated the effect of current use of promethazine. Bias increased for one-stage meta-analysis with increasing (1) between-database variance of exposure effect and (2) heterogeneous confounding generated by two covariates. The efficiency of one-stage meta-analysis was slightly lower than that of two-stage meta-analysis for the majority of investigated scenarios. Based on ARITMO data, there were no evident differences between one-stage (OR = 1.50, CI = [1.08; 2.08]) and two-stage (OR = 1.55, CI = [1.12; 2.16]) approaches. When the effect of interest is heterogeneous, a one-stage meta-analysis ignoring clustering gives biased estimates. Two-stage meta-analysis generates estimates at least as accurate and precise as one-stage meta-analysis. However, in a study using small databases and rare exposures and/or outcomes, a correct one-stage meta-analysis becomes essential. Copyright © 2017 John Wiley & Sons, Ltd.

Combined application of eicosapentaenoic acid and docosahexaenoic acid on depression in women: a meta-analysis of double-blind randomized controlled trials

Directory of Open Access Journals (Sweden)

Yang JR

2015-08-01

Full Text Available Jia-run Yang, Dong Han, Zheng-xue Qiao, Xue Tian, Dong Qi, Xiao-hui QiuDepartment of Medical Psychology, Public Health Institute of Harbin Medical University, Harbin, Heilongjiang Province, People’s Republic of ChinaObjectives: Previous randomized controlled trials (RCTs suggest that depression can be effectively treated by omega-3 polyunsaturated fatty acids (PUFAs. Therefore, we conducted this meta-analysis to systematically evaluate the clinical applicability of the combination of docosahexaenoic acid (DHA and eicosapentaenoic acid (EPA, which are the two major bioactive types of PUFAs, in depressed women.Methods: RCTs that compared the combination of DHA and EPA to placebo for short-course treatment of depression in women were systematically reviewed up to March 2015. Outcome measurement was the standardized difference in means in clinical measure of depression severity. Random effect model was performed. Meta-regression analysis was performed to assess the effects of baseline depression scores.Results: Data were obtained from eight RCTs. In these RCTs, 182 patients received placebo and 185 patients received DHA and EPA. The pooled standardized difference in mean was 0.65 with 95% CI = [0.18, 1.12]. There was no relation between the efficacy and the baseline depression scores. The sensitivity analysis found that the combination of EPA and DHA as monotherapy yielded a standardized difference in means of 0.65 (95% CI =0.41, 0.90 without heterogeneity.Discussion: These results indicate a beneficial effect of the combination of EPA and DHA on depressed mood in women compared with placebo. The clinical applicability of EPA and DHA showed greater promise and should be further explored.Keywords: depression, omega-3 polyunsaturated fatty acids, PUFAs, docosahexaenoic acid, DHA, eicosapentaenoic acid, EPA

Trial Sequential Analysis in systematic reviews with meta-analysis

DEFF Research Database (Denmark)

Wetterslev, Jørn; Jakobsen, Janus Christian; Gluud, Christian

2017-01-01

BACKGROUND: Most meta-analyses in systematic reviews, including Cochrane ones, do not have sufficient statistical power to detect or refute even large intervention effects. This is why a meta-analysis ought to be regarded as an interim analysis on its way towards a required information size...... from traditional meta-analyses using unadjusted naïve 95% confidence intervals and 5% thresholds for statistical significance. Spurious conclusions in systematic reviews with traditional meta-analyses can be reduced using Trial Sequential Analysis. Several empirical studies have demonstrated...

Effectiveness of combined regional-general anesthesia for reducing mortality in coronary artery bypass: meta-analysis

Directory of Open Access Journals (Sweden)

Fabiano Timbó Barbosa

2016-04-01

Full Text Available ABSTRACT BACKGROUND AND OBJECTIVES: Neuraxial anesthesia (NA has been used in association with general anesthesia (GA for coronary artery bypass; however, anticoagulation during surgery makes us question the viability of benefits by the risk of epidural hematoma. The aim of this study was to perform a meta-analyzes examining the efficacy of NA associated with GA compared to GA alone for coronary artery bypass on mortality reduction. METHODS: Mortality, arrhythmias, cerebrovascular accident (CVA, myocardial infarction (MI, length of hospital stay (LHS, length of ICU stay (ICUS, reoperations, blood transfusion (BT, quality of life, satisfaction degree, and postoperative cognitive dysfunction were analyzed. The weighted mean difference (MD was estimated for continuous variables, and relative risk (RR and risk difference (RD for categorical variables. RESULTS: 17 original articles analyzed. Meta-analysis of mortality (RD = -0.01, 95% CI = -0.03 to 0.01, CVA (RR = 0.79, 95% CI = 0.32-1.95, MI (RR = 0.96, 95% CI = 0.52-1.79 and LHS (MD = -1.94, 95% CI = -3.99 to 0.12 were not statistically significant. Arrhythmia was less frequent with NA (RR = 0.68, 95% CI = 0.50-0.93. ICUS was lower in NA (MD = -2.09, 95% CI = -2.92 to -1.26. CONCLUSION: There was no significant difference in mortality. Combined NA and GA showed lower incidence of arrhythmias and lower ICUS.

Online open neuroimaging mass meta-analysis

DEFF Research Database (Denmark)

Nielsen, Finn Årup; Kempton, Matthew J.; Williams, Steven C. R.

We describe a system for meta-analysis where a wiki stores numerical data in a simple format and a web service performs the numerical computation. We initially apply the system on multiple meta-analyses of structural neuroimaging data results. The described system allows for mass meta-analysis, e...

Hydropower externalities: A meta-analysis

International Nuclear Information System (INIS)

Mattmann, Matteo; Logar, Ivana; Brouwer, Roy

2016-01-01

This paper presents a meta-analysis of existing research related to the economic valuation of the external effects of hydropower. A database consisting of 81 observations derived from 29 studies valuing the non-market impacts of hydropower electricity generation is constructed with the main aim to quantify and explain the economic values for positive and negative hydropower externalities. Different meta-regression model specifications are used to test the robustness of significant determinants of non-market values, including different types of hydropower impacts. The explanatory and predictive power of the estimated models is relatively high. Whilst controlling for sample and study characteristics, we find significant evidence for public aversion towards deteriorations of landscape, vegetation and wildlife caused by hydropower projects. There is however only weak evidence of willingness to pay for mitigating these effects. The main positive externality of hydropower generation, the avoidance of greenhouse gas emission, positively influences welfare estimates when combined with the share of hydropower in national energy production. Sensitivity to scope is detected, but not linked to specific externalities or non-market valuation methods. - Highlights: • A global meta-analysis of valuation studies of hydropower externalities is presented. • Positive and negative externalities are distinguished. • Welfare losses due to environmental deteriorations outweigh gains of GHG reductions. • There is only weak evidence of public WTP for mitigating negative externalities. • The non-market values of hydropower externalities are sensitive to scope.

Meta-DiSc: a software for meta-analysis of test accuracy data.

Science.gov (United States)

Zamora, Javier; Abraira, Victor; Muriel, Alfonso; Khan, Khalid; Coomarasamy, Arri

2006-07-12

Systematic reviews and meta-analyses of test accuracy studies are increasingly being recognised as central in guiding clinical practice. However, there is currently no dedicated and comprehensive software for meta-analysis of diagnostic data. In this article, we present Meta-DiSc, a Windows-based, user-friendly, freely available (for academic use) software that we have developed, piloted, and validated to perform diagnostic meta-analysis. Meta-DiSc a) allows exploration of heterogeneity, with a variety of statistics including chi-square, I-squared and Spearman correlation tests, b) implements meta-regression techniques to explore the relationships between study characteristics and accuracy estimates, c) performs statistical pooling of sensitivities, specificities, likelihood ratios and diagnostic odds ratios using fixed and random effects models, both overall and in subgroups and d) produces high quality figures, including forest plots and summary receiver operating characteristic curves that can be exported for use in manuscripts for publication. All computational algorithms have been validated through comparison with different statistical tools and published meta-analyses. Meta-DiSc has a Graphical User Interface with roll-down menus, dialog boxes, and online help facilities. Meta-DiSc is a comprehensive and dedicated test accuracy meta-analysis software. It has already been used and cited in several meta-analyses published in high-ranking journals. The software is publicly available at http://www.hrc.es/investigacion/metadisc_en.htm.

Comparison of diagnostic efficacy between CLE, tissue sampling, and CLE combined with tissue sampling for undetermined pancreaticobiliary strictures: a meta-analysis.

Science.gov (United States)

Gao, Ya-Dong; Qu, Ya-Wei; Liu, Hai-Feng

2018-04-01

The accurate diagnosis of undetermined pancreaticobiliary strictures remains challenging. Current ERCP-guided tissue sampling methods are of low sensitivity. Confocal laser endomicroscopy (CLE) is a new procedure and allows real optical biopsies that may improve the diagnosis of undetermined pancreaticobiliary strictures. The aim of this meta-analysis was to determine the diagnostic yield of CLE, tissue sampling, and CLE combined with tissue sampling for undetermined pancreaticobiliary strictures. Pubmed, Embase, and the Cochrane Library database were reviewed for relevant studies. Pooled estimates of sensitivity and specificity with 95% confidence intervals (CIs) were calculated using the random-effects meta-analysis model. The summary receiver-operating characteristic (SROC) curve was constructed, and the area under the receiver operating characteristic curve (AUC) was calculated. Twelve studies involving 591 patients were enrolled in our analysis. The overall sensitivity and the specificity estimate of CLE for discriminating benign and malignant pancreaticobiliary strictures were 87% (95%CI, 83-91%) and 76% (95%CI, 70-81%), respectively. The AUC to assess the diagnostic efficacy was 0.8705. For tissue sampling, the overall sensitivity and the specificity estimate were 64% (95%CI, 57-70%) and 94% (95%CI, 90-97%), respectively. The AUC to assess the diagnostic efficacy was 0.8040. A combination of both methods increased the sensitivity (93%; 95%CI, 88-96%) with a specificity of 82% (95%CI, 74-89%). The AUC to assess the diagnostic efficacy was 0.9377. There was no publication bias by Deeks' Funnel Plot with p = .936. Compared with tissue sampling, CLE may increase the sensitivity for the diagnosis of malignant pancreaticobiliary strictures. A combination of both can effectively diagnose malignant pancreaticobiliary strictures.

Prevalence of rapid eye movement sleep behavior disorder (RBD) in Parkinson's disease: a meta and meta-regression analysis.

Science.gov (United States)

Zhang, Xiaona; Sun, Xiaoxuan; Wang, Junhong; Tang, Liou; Xie, Anmu

2017-01-01

Rapid eye movement sleep behavior disorder (RBD) is thought to be one of the most frequent preceding symptoms of Parkinson's disease (PD). However, the prevalence of RBD in PD stated in the published studies is still inconsistent. We conducted a meta and meta-regression analysis in this paper to estimate the pooled prevalence. We searched the electronic databases of PubMed, ScienceDirect, EMBASE and EBSCO up to June 2016 for related articles. STATA 12.0 statistics software was used to calculate the available data from each research. The prevalence of RBD in PD patients in each study was combined to a pooled prevalence with a 95 % confidence interval (CI). Subgroup analysis and meta-regression analysis were performed to search for the causes of the heterogeneity. A total of 28 studies with 6869 PD cases were deemed eligible and included in our meta-analysis based on the inclusion and exclusion criteria. The pooled prevalence of RBD in PD was 42.3 % (95 % CI 37.4-47.1 %). In subgroup analysis and meta-regression analysis, we found that the important causes of heterogeneity were the diagnosis criteria of RBD and age of PD patients (P = 0.016, P = 0.019, respectively). The results indicate that nearly half of the PD patients are suffering from RBD. Older age and longer duration are risk factors for RBD in PD. We can use the minimal diagnosis criteria for RBD according to the International Classification of Sleep Disorders to diagnose RBD patients in our daily work if polysomnography is not necessary.

Likelihood ratio meta-analysis: New motivation and approach for an old method.

Science.gov (United States)

Dormuth, Colin R; Filion, Kristian B; Platt, Robert W

2016-03-01

A 95% confidence interval (CI) in an updated meta-analysis may not have the expected 95% coverage. If a meta-analysis is simply updated with additional data, then the resulting 95% CI will be wrong because it will not have accounted for the fact that the earlier meta-analysis failed or succeeded to exclude the null. This situation can be avoided by using the likelihood ratio (LR) as a measure of evidence that does not depend on type-1 error. We show how an LR-based approach, first advanced by Goodman, can be used in a meta-analysis to pool data from separate studies to quantitatively assess where the total evidence points. The method works by estimating the log-likelihood ratio (LogLR) function from each study. Those functions are then summed to obtain a combined function, which is then used to retrieve the total effect estimate, and a corresponding 'intrinsic' confidence interval. Using as illustrations the CAPRIE trial of clopidogrel versus aspirin in the prevention of ischemic events, and our own meta-analysis of higher potency statins and the risk of acute kidney injury, we show that the LR-based method yields the same point estimate as the traditional analysis, but with an intrinsic confidence interval that is appropriately wider than the traditional 95% CI. The LR-based method can be used to conduct both fixed effect and random effects meta-analyses, it can be applied to old and new meta-analyses alike, and results can be presented in a format that is familiar to a meta-analytic audience. Copyright © 2016 Elsevier Inc. All rights reserved.

Network meta-analysis: an introduction for pharmacists.

Science.gov (United States)

Xu, Yina; Amiche, Mohamed Amine; Tadrous, Mina

2018-05-21

Network meta-analysis is a new tool used to summarize and compare studies for multiple interventions, irrespective of whether these interventions have been directly evaluated against each other. Network meta-analysis is quickly becoming the standard in conducting therapeutic reviews and clinical guideline development. However, little guidance is available to help pharmacists review network meta-analysis studies in their practice. Major institutions such as the Cochrane Collaboration, Agency for Healthcare Research and Quality, Canadian Agency for Drugs and Technologies in Health, and National Institute for Health and Care Excellence Decision Support Unit have endorsed utilizing network meta-analysis to establish therapeutic evidence and inform decision making. Our objective is to introduce this novel technique to pharmacy practitioners, and highlight key assumptions behind network meta-analysis studies.

Efficacy Comparison of Six Chemotherapeutic Combinations for Osteosarcoma and Ewing's Sarcoma Treatment: A Network Meta-Analysis.

Science.gov (United States)

Zhang, Tao; Zhang, Song; Yang, Feifei; Wang, Lili; Zhu, Sigang; Qiu, Bing; Li, Shunhua; Deng, Zhongliang

2018-01-01

This study aimed to address the insufficiency of traditional meta-analysis and provide improved guidelines for the clinical practice of osteosarcoma treatment. The heterogeneity of the fixed-effect model was calculated, and when necessary, a random-effect model was adopted. Furthermore, the direct and indirect evidence was pooled together and exhibited in the forest plot and slash table. The surface under the cumulative ranking curve (SUCRA) value was also measured to rank each intervention. Finally, heat plot was introduced to demonstrate the contribution of each intervention and the inconsistency between direct and indirect comparisons. This network meta-analysis included 32 trials, involving a total of 5,626 subjects reported by 28 articles. All the treatments were classified into six chemotherapeutic combinations: dual agent with or without ifosfamide (IFO), multi-agent with or without IFO, and dual agent or multi-agent with IFO and etoposide. For the primary outcomes, both overall survival (OS) and event-free survival (EFS) rates were considered. The multi-agent integrated with IFO and etoposide showed an optimal performance for 5-year OS, 10-year OS, 3-year EFS, 5-year EFS, and 10-year EFS when compared with placebo. The SUCRA value of this treatment was also the highest of these six interventions. However, multi-drug with IFO alone had the highest SUCRA value of 0.652 and 0.516 when it came to relapse and lung-metastasis. It was efficient to some extent, but no significant difference was observed in both outcomes. Chemotherapy, applied as induction or adjuvant treatment with radiation therapy or surgery, is able to increase the survival rate of patients, especially by combining multi-drug with IFO and etoposide, which demonstrated the best performance in both OS and EFS. As for relapse and the lung-metastasis, multiple agents with IFO alone seemed to have the optimal efficiency, although no significant difference was observed here. J. Cell. Biochem. 119: 250

Efficacy and safety of radiofrequency ablation combined with transcatheter arterial chemoembolization for hepatocellular carcinomas compared with radiofrequency ablation alone: A time to event meta-analysis

Energy Technology Data Exchange (ETDEWEB)

Wang, Xin; Hu, Yanan; Ren, Mudan; Lu, Xin Lan; Lu, Gui Fang; He, Shui Xiang [Dept. of Gastroenterology, First Affiliated Hospital of Xi' an Jiaotong University, Xi' an (China)

2016-02-15

To compare the efficacy and safety of combined radiofrequency ablation (RFA) and transcatheter arterial chemoembolization (TACE) with RFA alone for hepatocellular carcinomas (HCC). Randomized controlled trial (RCT) studies that compared the clinical or oncologic outcomes of combination therapy of TACE and RFA versus RFA for the treatment of HCC were identified through literature searches of electronic databases (Pubmed, Embase, Cochrane Library, China Biology Medicine disc, China National Knowledge Infrastructure, and Google Scholar). Hazard ratios (HRs) or odds ratios (ORs) with their corresponding 95% confidence interval (CI) were combined as the effective value to assess the summary effects. The strength of evidence was rated by the Grading of Recommendations Assessment, Development, and Evaluation system. Six RCTs with 534 patients were eligible for inclusion in this meta-analysis. The meta-analysis showed that the combination of TACE and RFA is associated with a significantly longer overall survival (HR = 0.62, 95% CI: 0.49-0.78, p < 0.001) and recurrence-free survival (HR = 0.55, 95% CI: 0.40-0.76, p < 0.001) in contrast with RFA monotherapy. The seemingly higher incidence of major complications in the combination group compared with RFA group did not reach statistical significance (OR = 1.17, 95% CI: 0.39-3.55, p = 0.78). In patients with HCC, the combination of TACE and RFA is associated with significantly higher overall survival and recurrence-free survival, as compared with RFA monotherapy, without significant difference in major complications.

Efficacy and safety of radiofrequency ablation combined with transcatheter arterial chemoembolization for hepatocellular carcinomas compared with radiofrequency ablation alone: A time to event meta-analysis

International Nuclear Information System (INIS)

Wang, Xin; Hu, Yanan; Ren, Mudan; Lu, Xin Lan; Lu, Gui Fang; He, Shui Xiang

2016-01-01

To compare the efficacy and safety of combined radiofrequency ablation (RFA) and transcatheter arterial chemoembolization (TACE) with RFA alone for hepatocellular carcinomas (HCC). Randomized controlled trial (RCT) studies that compared the clinical or oncologic outcomes of combination therapy of TACE and RFA versus RFA for the treatment of HCC were identified through literature searches of electronic databases (Pubmed, Embase, Cochrane Library, China Biology Medicine disc, China National Knowledge Infrastructure, and Google Scholar). Hazard ratios (HRs) or odds ratios (ORs) with their corresponding 95% confidence interval (CI) were combined as the effective value to assess the summary effects. The strength of evidence was rated by the Grading of Recommendations Assessment, Development, and Evaluation system. Six RCTs with 534 patients were eligible for inclusion in this meta-analysis. The meta-analysis showed that the combination of TACE and RFA is associated with a significantly longer overall survival (HR = 0.62, 95% CI: 0.49-0.78, p < 0.001) and recurrence-free survival (HR = 0.55, 95% CI: 0.40-0.76, p < 0.001) in contrast with RFA monotherapy. The seemingly higher incidence of major complications in the combination group compared with RFA group did not reach statistical significance (OR = 1.17, 95% CI: 0.39-3.55, p = 0.78). In patients with HCC, the combination of TACE and RFA is associated with significantly higher overall survival and recurrence-free survival, as compared with RFA monotherapy, without significant difference in major complications

The Efficacy and Safety of Tamsulosin Combined with Extracorporeal Shockwave Lithotripsy for Urolithiasis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Science.gov (United States)

Chen, Kai; Mi, Hua; Xu, Guangyu; Liu, Lin; Sun, Xiubin; Wang, Shiping; Meng, Qingrong; Lv, Tao

2015-10-01

Many studies have been conducted to investigate adjunctive tamsulosin therapy after extracorporeal shockwave lithotripsy (SWL) for urolithiasis. The results from those studies, however, are still inconsistent. Therefore, we performed a meta-analysis to provide an update on the clinical efficacy and safety of tamsulosin combined with SWL for urolithiasis. A systematic search was performed in PubMed, Cochrane Library, and Embase to identify all relevant randomized controlled trials until January 2015. Two reviewers independently assessed trial quality and extracted data. Meta-analysis was conducted with Review Manager (RevMan), version 5.1. Twenty-one studies (2093 subjects in total) were identified in the current meta-analysis. Compared with a control group, the experimental group (tamsulosin combined with SWL) showed an increased overall benefit for stone expulsion, with pooled risk ratio (RR) of 1.20 (95% confidence interval [CI], 1.15-1.26). With respect to the different geographic regions, European and American had a high possibility of improvement in stone expulsion (RR: 1.33, 95% CI, 1.19-1.49). According to the stone locations (renal, upper and lower ureteral) and sizes (4-10 mm and 11-24 mm), tamsulosin is more useful for lower ureteral stone (RR: 1.28; 95% CI, 1.14-1.43) and larger sized stones (RR: 1.49; 95% CI, 1.28-1.75). The effect estimates did not vary markedly when stratified by follow-up durations but varied by dose of tamsulosin. Furthermore, a shorter expulsion time, reduced occurrence of steinstrasse, fewer incidences of colic, and lower analgesic requirements were observed within the experimental group. In addition, tamsulosin is well tolerated, and its adverse events rarely led to dropouts of patients. Overall, evidence suggests that tamsulosin combined with SWL is safe and effective in enhancing stone expulsion for patients with urolithiasis. Furthermore, high-quality, randomized and placebo-controlled trials evaluating the efficacy and

Meta-analysis of SNPs involved in variance heterogeneity using Levene's test for equal variances

Science.gov (United States)

Deng, Wei Q; Asma, Senay; Paré, Guillaume

2014-01-01

Meta-analysis is a commonly used approach to increase the sample size for genome-wide association searches when individual studies are otherwise underpowered. Here, we present a meta-analysis procedure to estimate the heterogeneity of the quantitative trait variance attributable to genetic variants using Levene's test without needing to exchange individual-level data. The meta-analysis of Levene's test offers the opportunity to combine the considerable sample size of a genome-wide meta-analysis to identify the genetic basis of phenotypic variability and to prioritize single-nucleotide polymorphisms (SNPs) for gene–gene and gene–environment interactions. The use of Levene's test has several advantages, including robustness to departure from the normality assumption, freedom from the influence of the main effects of SNPs, and no assumption of an additive genetic model. We conducted a meta-analysis of the log-transformed body mass index of 5892 individuals and identified a variant with a highly suggestive Levene's test P-value of 4.28E-06 near the NEGR1 locus known to be associated with extreme obesity. PMID:23921533

Systematic review and network meta-analysis of combination and monotherapy treatments in disease-modifying antirheumatic drug-experienced patients with rheumatoid arthritis: analysis of American College of Rheumatology criteria scores 20, 50, and 70

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Orme, Michelle E; MacGilchrist, Katherine S; Mitchell, Stephen; Spurden, Dean; Bird, Alex

2012-01-01

Background Biologic disease-modifying antirheumatic drugs (bDMARDs) extend the treatment choices for rheumatoid arthritis patients with suboptimal response or intolerance to conventional DMARDs. The objective of this systematic review and meta-analysis was to compare the relative efficacy of EU-licensed bDMARD combination therapy or monotherapy for patients intolerant of or contraindicated to continued methotrexate. Methods Comprehensive, structured literature searches were conducted in Medline, Embase, and the Cochrane Library, as well as hand-searching of conference proceedings and reference lists. Phase II or III randomized controlled trials reporting American College of Rheumatology (ACR) criteria scores of 20, 50, and 70 between 12 and 30 weeks’ follow-up and enrolling adult patients meeting ACR classification criteria for rheumatoid arthritis previously treated with and with an inadequate response to conventional DMARDs were eligible. To estimate the relative efficacy of treatments whilst preserving the randomized comparisons within each trial, a Bayesian network meta-analysis was conducted in WinBUGS using fixed and random-effects, logit-link models fitted to the binomial ACR 20/50/70 trial data. Results The systematic review identified 10,625 citations, and after a review of 2450 full-text papers, there were 29 and 14 eligible studies for the combination and monotherapy meta-analyses, respectively. In the combination analysis, all licensed bDMARD combinations had significantly higher odds of ACR 20/50/70 compared to DMARDs alone, except for the rituximab comparison, which did not reach significance for the ACR 70 outcome (based on the 95% credible interval). The etanercept combination was significantly better than the tumor necrosis factor-α inhibitors adalimumab and infliximab in improving ACR 20/50/70 outcomes, with no significant differences between the etanercept combination and certolizumab pegol or tocilizumab. Licensed-dose etanercept, adalimumab

Meta-Analysis at Middle Age: A Personal History

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Glass, Gene V.

2015-01-01

The 40-year history of meta-analysis is traced from the vantage point of one of its originators. Research syntheses leading to the first examples of meta-analysis are identified. Early meta-analyses of the literature on psychotherapy outcomes and school class size are recounted. The influence on the development of meta-analysis of several…

The Efficacy and Clinical Safety of Various Analgesic Combinations for Post-Operative Pain after Third Molar Surgery: A Systematic Review and Meta-Analysis.

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Alvin Ho Yeung Au

Full Text Available To run a systematic review and meta-analysis of randomized clinical trials aiming to answer the clinical question "which analgesic combination and dosage is potentially the most effective and safe for acute post-operative pain control after third molar surgery?".A systematic search of computer databases and journals was performed. The search and the evaluations of articles were performed by 2 independent reviewers in 3 rounds. Randomized clinical trials related to analgesic combinations for acute post-operative pain control after lower third molar surgery that matched the selection criteria were evaluated to enter in the final review.Fourteen studies with 3521 subjects, with 10 groups (17 dosages of analgesic combinations were included in the final review. The analgesic efficacy were presented by the objective pain measurements including sum of pain intensity at 6 hours (SPID6 and total pain relief at 6 hours (TOTPAR6. The SPID6 scores and TOTPAR6 scores of the reported analgesic combinations were ranged from 1.46 to 6.44 and 3.24 - 10.3, respectively. Ibuprofen 400mg with oxycodone HCL 5mg had superior efficacy (SPID6: 6.44, TOTPAR6: 9.31. Nausea was the most common adverse effect, with prevalence ranging from 0-55%. Ibuprofen 200mg with caffeine 100mg or 200mg had a reasonable analgesic effect with fewer side effects.This systematic review and meta-analysis may help clinicians in their choices of prescribing an analgesic combination for acute post-operative pain control after lower third molar surgery. It was found in this systematic review Ibuprofen 400mg combined with oxycodone HCL 5mg has superior analgesic efficacy when compared to the other analgesic combinations included in this study.

Psychotherapy, Pharmacotherapy, and Their Combination for Adolescents with Major Depressive Disorder: A Meta-Analysis

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Singh, Nikita; Reece, John

2014-01-01

This meta-analysis aims to inform clinical practice of treatment strategies for adolescents with major depressive disorder (MDD). The efficacy of three empirically validated treatments was compared to determine the most effective treatment. These were: cognitive-behavioural therapy (CBT), selective serotonin reuptake inhibitor (SSRI)…

Statistical Power in Meta-Analysis

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Liu, Jin

2015-01-01

Statistical power is important in a meta-analysis study, although few studies have examined the performance of simulated power in meta-analysis. The purpose of this study is to inform researchers about statistical power estimation on two sample mean difference test under different situations: (1) the discrepancy between the analytical power and…

Interleukin-8 for diagnosis of neonatal sepsis: a meta-analysis.

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Min Zhou

Full Text Available Neonatal sepsis (NS is a life-threatening disorder and an important cause of morbidity and mortality in neonates. Previous studies showed that interleukin 8 (IL-8 may effectively and rapidly diagnose NS.We conducted the systematic review and meta-analysis to investigate the diagnostic value of the IL-8 in NS.The literature was searched in PUBMED, EMBASE, Cochrane Library, CNKI, VIP and other Chinese Medical Databases during October 1998 to January 2014 using set search criteria. Each included study was evaluated by quality assessment of diagnostic accuracy studies tool. Two investigators independently extracted the data and study characteristics, and disagreements, if any, were resolved by consensus. Meta-disc software was used to calculate the pooled sensitivity, specificity and summary diagnostic odds ratio (SDOR, I² or Cochrane Q to test heterogeneity, and meta-regression to investigate the source of heterogeneity. Funnel plots were used to test the potential presence of publication bias. False-positive report probability (FPRP was calculated to confirm the significance of the results.Eight studies (548 neonates were included in this meta-analysis. The pooled sensitivity and specificity of IL-8 were 0.78 and 0.84, respectively, which had moderate accuracy in the diagnosis of NS. The pooled diagnostic odds ratio (DOR and area under curve (AUC was 21.64 and 0.8908 (Q*=0.8215, respectively. The diagnostic threshold analysis showed that there was no threshold effect. The meta-regression analysis showed the cut-off, QUADAS and onset time have no effect on the heterogeneity. The funnel plots showed the existence of publication bias.Meta-analysis showed IL-8 had a moderate accuracy (AUC=0.8908 for the diagnosis of NS. IL-8 is a helpful biomarker for early diagnosis of NS. However, we should combine the results with clinical symptoms and signs, laboratory and microbial results.

Novel non-HLA-susceptible regions determined by meta-analysis of ...

Indian Academy of Sciences (India)

We identified novel non-HLA-susceptible regions for ankylosing spondylitis (AS) by applying the genome-search-meta-analysis (GSMA) method to combine the previous four AS genomewide scan studies including 479 families with 1175 affected individuals. Three original genomescans were mainly analysed for Caucasian ...

Two-stage open reduction and internal fixation versus limited internal fixation combined with external fixation: a meta-analysis of postoperative complications in patients with severe Pilon fractures.

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Cui, Xueliang; Chen, Hui; Rui, Yunfeng; Niu, Yang; Li, He

2018-01-01

Objectives Two-stage open reduction and internal fixation (ORIF) and limited internal fixation combined with external fixation (LIFEF) are two widely used methods to treat Pilon injury. However, which method is superior to the other remains controversial. This meta-analysis was performed to quantitatively compare two-stage ORIF and LIFEF and clarify which method is better with respect to postoperative complications in the treatment of tibial Pilon fractures. Methods We conducted a meta-analysis to quantitatively compare the postoperative complications between two-stage ORIF and LIFEF. Eight studies involving 360 fractures in 359 patients were included in the meta-analysis. Results The two-stage ORIF group had a significantly lower risk of superficial infection, nonunion, and bone healing problems than the LIFEF group. However, no significant differences in deep infection, delayed union, malunion, arthritis symptoms, or chronic osteomyelitis were found between the two groups. Conclusion Two-stage ORIF was associated with a lower risk of postoperative complications with respect to superficial infection, nonunion, and bone healing problems than LIFEF for tibial Pilon fractures. Level of evidence 2.

A Review and Meta-Analysis of Country-of-Origin Research

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Verlegh, P.W.J.; Steenkamp, J.E.B.M.

1999-01-01

Despite a large body of research, country-of-origin effects are still poorly understood. Combining the strengths of a narrative review with those of a quantitative meta-analysis, our study seeks to establish a firm grounding for country-of-origin research. We review previous country-of-origin

Formalizing the definition of meta-analysis in Molecular Ecology.

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ArchMiller, Althea A; Bauer, Eric F; Koch, Rebecca E; Wijayawardena, Bhagya K; Anil, Ammu; Kottwitz, Jack J; Munsterman, Amelia S; Wilson, Alan E

2015-08-01

Meta-analysis, the statistical synthesis of pertinent literature to develop evidence-based conclusions, is relatively new to the field of molecular ecology, with the first meta-analysis published in the journal Molecular Ecology in 2003 (Slate & Phua 2003). The goal of this article is to formalize the definition of meta-analysis for the authors, editors, reviewers and readers of Molecular Ecology by completing a review of the meta-analyses previously published in this journal. We also provide a brief overview of the many components required for meta-analysis with a more specific discussion of the issues related to the field of molecular ecology, including the use and statistical considerations of Wright's FST and its related analogues as effect sizes in meta-analysis. We performed a literature review to identify articles published as 'meta-analyses' in Molecular Ecology, which were then evaluated by at least two reviewers. We specifically targeted Molecular Ecology publications because as a flagship journal in this field, meta-analyses published in Molecular Ecology have the potential to set the standard for meta-analyses in other journals. We found that while many of these reviewed articles were strong meta-analyses, others failed to follow standard meta-analytical techniques. One of these unsatisfactory meta-analyses was in fact a secondary analysis. Other studies attempted meta-analyses but lacked the fundamental statistics that are considered necessary for an effective and powerful meta-analysis. By drawing attention to the inconsistency of studies labelled as meta-analyses, we emphasize the importance of understanding the components of traditional meta-analyses to fully embrace the strengths of quantitative data synthesis in the field of molecular ecology. © 2015 John Wiley & Sons Ltd.

A meta-analysis of hyperfractionated and accelerated radiotherapy and combined chemotherapy and radiotherapy regimens in unresected locally advanced squamous cell carcinoma of the head and neck

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Budach V

2006-01-01

Full Text Available Abstract Background Former meta-analyses have shown a survival benefit for the addition of chemotherapy (CHX to radiotherapy (RT and to some extent also for the use of hyperfractionated radiation therapy (HFRT and accelerated radiation therapy (AFRT in locally advanced squamous cell carcinoma (SCC of the head and neck. However, the publication of new studies and the fact that many older studies that were included in these former meta-analyses used obsolete radiation doses, CHX schedules or study designs prompted us to carry out a new analysis using strict inclusion criteria. Methods Randomised trials testing curatively intended RT (≥60 Gy in >4 weeks/>50 Gy in Results Thirty-two trials with a total of 10 225 patients were included into the meta-analysis. An overall survival benefit of 12.0 months was observed for the addition of simultaneous CHX to either CFRT or HFRT/AFRT (p Conclusion RT combined with simultaneous 5-FU, cisplatin, carboplatin, and mitomycin C as single drug or combinations of 5-FU with one of the other drugs results in a large survival advantage irrespective the employed radiation schedule. If radiation therapy is used as single modality, hyperfractionation leads to a significant improvement of overall survival. Accelerated radiation therapy alone, especially when given as split course radiation schedule or extremely accelerated treatments with decreased total dose, does not increase overall survival.

Determining The Factors Affecting Fruit Hardness of Different Peach Types with Meta Analysis

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Hande Küçükönder

2014-09-01

Full Text Available The aim of this study is to determine the factor effective in determining the hardness of Caterina, Suidring, Royal Glory and Tirrenia peach types using meta analysis. In the study, the impact force (Fi and the contact time (tc were detected and the impulse values (I that are expressed as independent variable in the area under the curve were calculated in the measurements performed using the technique of a low-mass lateral impactor multiplicated with peach. Using the theory of elasticity, the independent variables were determined as Fmax (maximum impact force, contact time (tmax, Fmax/tmax, 1/tmax, 1/tmax2,5, Fmax/tmax 1.25 and Fmax2.5 parameters. The correlation coefficient values showing the relationship between these parameters and the dependent variable Magness-Taylor force (MT were calculated and were combined with meta-analysis by using the Hunter-Schmid and Fisher’s Z methods. The Cohen’s classification criterion was used in evaluating the resulting mean effect size (combined correlation value and in determining its direction. As a result of the meta-analysis, the mean effect size according to Hunter-Schmid method was found 0.436 (0.371-0.497 positively directed in 95% confidence interval, while it was found 0.468 (0.390-0.545 according to Fisher’s Z method. The effect sizes in both methods were determined “mid-level” according to the Cohen’s classification. When the significance level of the studies was analyzed with the Z test, all of the ones that taken into the meta analysis has been found statistically significant. As a result of the meta analysis in this study evaluating the relationship of peach types with the fruit hardness, the mean effect size has been found to reach “strong level”. Consequently, “maximum shock acceleration” was found to be a more effective factor comparing to the other factors in determining the the fruit hardness according to the results of meta analysis applied in both methods.

Combination therapy of fenofibrate and ursodeoxycholic acid in patients with primary biliary cirrhosis who respond incompletely to UDCA monotherapy: a meta-analysis

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Zhang Y

2015-05-01

Full Text Available Yan Zhang,1,2,* Sainan Li,1,* Lei He,1 Fan Wang,1 Kan Chen,1 Jingjing Li,1 Tong Liu,1 Yuanyuan Zheng,1 Jianrong Wang,1,3 Wenxia Lu,1,3 Yuqing Zhou,1,4 Qin Yin,1,4 Yujing Xia,1 Yingqun Zhou,1 Jie Lu,1 Chuanyong Guo1 1Department of Gastroenterology, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai, 2Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 3The First Clinical Medical College of Nanjing Medical University, Nanjing, 4The First Affiliated Hospital of Soochow University, Suzhou, People’s Republic of China *These authors contributed equally to this work Background: Although the effectiveness of treatment with ursodeoxycholic acid (UDCA and fenofibrate for primary biliary cirrhosis (PBC has been suggested by small trials, a systematic review to summarize the evidence has not yet been carried out.Methods: A meta-analysis of all long-term randomized controlled trials comparing the combination of UDCA and fenofibrate with UDCA monotherapy was performed via electronic searches.Results: Six trials, which included 84 patients, were assessed. Combination therapy with UDCA and fenofibrate was more effective than UDCA monotherapy in improving alkaline phosphatase (mean difference [MD]: -90.44 IU/L; 95% confidence interval [CI]: -119.95 to -60.92; P<0.00001, gamma-glutamyl transferase (MD: -61.58 IU/L; 95% CI: -122.80 to -0.35; P=0.05, immunoglobulin M (MD: -38.45 mg/dL; 95% CI: -64.38 to -12.51; P=0.004, and triglycerides (MD: -0.41 mg/dL; 95% CI: -0.82 to -0.01; P=0.05. However, their effects on pruritus (odds ratio [OR]: 0.39; 95% CI: 0.09–1.78; P=0.23, total bilirubin (MD: -0.05 mg/dL; 95% CI: -0.21 to 0.12; P=0.58, and alanine aminotransferase (MD: -3.31 IU/L; 95% CI: -14.60 to 7.97; P=0.56 did not differ significantly. This meta-analysis revealed no significant differences in the incidence of adverse events (OR: 0.21; 95% CI: 0.03–1.25; P=0.09 between patients treated with

Effect of Influenza Vaccination of Children on Infection Rate in Hutterite Communities: Follow-Up Study of a Randomized Trial.

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Biao Wang

Full Text Available An earlier cluster randomized controlled trial (RCT of Hutterite colonies had shown that if more than 80% of children and adolescents were immunized with influenza vaccine there was a statistically significant reduction in laboratory-confirmed influenza among all unimmunized community members. We assessed the impact of this intervention for two additional influenza seasonal periods.Follow-up data for two influenza seasonal periods of a cluster randomized trial involving 1053 Canadian children and adolescents aged 36 months to 15 years in Season 2 and 1014 in Season 3 who received the study vaccine, and 2805 community members in Season 2 and 2840 in Season 3 who did not receive the study vaccine. Follow-up for Season 2 began November 18, 2009 and ended April 25, 2010 while Season 3 extended from December 6, 2010 and ended May 27, 2011. Children were randomly assigned in a blinded manner according to community membership to receive either inactivated trivalent influenza vaccine or hepatitis A. The primary outcome was confirmed influenza A and B infection using RT-PCR assay. Due to the outbreak of 2009 H1N1 pandemic, data in Season 2 were excluded for analysis.For an analysis of the combined Season 1 and Season 3 data, among non-recipients (i.e., participants who did not receive study vaccines, 66 of the 2794 (2.4% participants in the influenza vaccine colonies and 121 of the 2301 (5.3% participants in the hepatitis A colonies had influenza confirmed by RT-PCR, for a protective effectiveness of 60% (95% CI, 6% to 83%; P = 0.04; among all study participants (i.e., including both those who received study vaccine and those who did not, 125 of the 3806 (3.3% in the influenza vaccine colonies and 239 of the 3243 (7.4% in the hepatitis A colonies had influenza confirmed by RT-PCR, for a protective effectiveness of 63% (95% CI, 5% to 85%; P = 0.04.Immunizing children and adolescents with inactivated influenza vaccine can offer a protective effect among

Comparison of the efficacy among multiple chemotherapeutic interventions combined with radiation therapy for patients with cervix cancer after surgery: A network meta-analysis.

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Chang, Lei; Guo, Ruixia

2017-07-25

Cervix cancer was the second most common cancer in female. However, there was no network meta-analysis (NMA) comparing the efficacy of the multiple chemotherapeutic interventions combined with radiation therapy in patients after operation. Randomized controlled trials were retrieved from PubMed, Embase and Cochrane Library. Overall survival (OS), recurrence-free survival (RFS), incidence of recurrence and distant metastasis were the main outcomes, particularly 5-year OS and PFS were considered as primary outcomes. Furthermore, the hazard ratio (HR) or odds ratio (OR) and their 95% credible intervals (CrIs) were extracted. The surface under cumulative ranking curve (SUCRA) was also used in this NMA. A total of 39 eligible trials with 8,952 patients were included and 22 common chemotherapies were evaluated in this meta-analysis. For OS, cisplatin+fluorouracil+hydroxyurea, fluorouracil+mitomycin C, cisplatin and cisplatin+fluorouracil were better than placebo. As for RFS, cisplatin+fluorouracil, fluorouracil+mitomycin C, and cisplatin alone had the significant superiority compared with placebo. In terms of incidence of recurrence, the optimal drug combination was cisplatin+ifosfamide (0.93) based on SUCRA. Moreover, epirubicin (OR = 0.28, 95% CrI: 0.08-0.91) was the only one had the distinguished potency in reducing the occurrence of distant metastasis with a SUCRA rank probability of 0.88. We recommended cisplatin+fluorouracil+hydroxyurea and cisplatin+docetaxel for their good efficacy in long term survival. Meanwhile, the combination of multiple drugs with different mechanisms worked better.

Meta-STEPP: subpopulation treatment effect pattern plot for individual patient data meta-analysis.

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Wang, Xin Victoria; Cole, Bernard; Bonetti, Marco; Gelber, Richard D

2016-09-20

We have developed a method, called Meta-STEPP (subpopulation treatment effect pattern plot for meta-analysis), to explore treatment effect heterogeneity across covariate values in the meta-analysis setting for time-to-event data when the covariate of interest is continuous. Meta-STEPP forms overlapping subpopulations from individual patient data containing similar numbers of events with increasing covariate values, estimates subpopulation treatment effects using standard fixed-effects meta-analysis methodology, displays the estimated subpopulation treatment effect as a function of the covariate values, and provides a statistical test to detect possibly complex treatment-covariate interactions. Simulation studies show that this test has adequate type-I error rate recovery as well as power when reasonable window sizes are chosen. When applied to eight breast cancer trials, Meta-STEPP suggests that chemotherapy is less effective for tumors with high estrogen receptor expression compared with those with low expression. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Evaluation of Individual and Combined Applications of Serum Biomarkers for Diagnosis of Hepatocellular Carcinoma: A Meta-Analysis

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Bin Hu

2013-12-01

Full Text Available The clinical value of Serum alpha-fetoprotein (AFP to detect early hepatocellular carcinoma (HCC has been questioned due to its low sensitivity and specificity found in recent years. Other than AFP, several new serum biomarkers including the circulating AFP isoform AFP-L3, des-gamma-carboxy prothrombin (DCP and Golgi protein-73 (GP73 have been identified as useful HCC markers. In this investigation, we review the current knowledge about these HCC-related biomarkers, and sum up the results of our meta-analysis on studies that have addressed the utility of these biomarkers in early detection and prognostic prediction of HCC. A systematic search in PubMed, Web of Science, and the Cochrane Library was performed for articles published in English from 1999 to 2012, focusing on serum biomarkers for HCC detection. Data on sensitivity and specificity of tests were extracted from 40 articles that met the inclusion criteria, and the summary receiver operating characteristic curve (sROC was obtained. A meta-analysis was carried out in which the area under the curve (AUC for each biomarker or biomarker combinations (AFP, DCP, GP73, AFP-L3, AFP + DCP, AFP + AFP-L3, and AFP + GP73 was used to compare the diagnostic accuracy of different biomarker tests. The AUC of AFP, DCP, GP73, AFP-L3, AFP + DCP, AFP + AFP-L3, and AFP + GP73 are 0.835, 0.797, 0.914, 0.710, 0.874, 0.748, and 0.932 respectively. A combination of AFP + GP73 is superior to AFP in detecting HCC and differentiating HCC patients from non-HCC patients, and may prove to be a useful marker in the diagnosis and screening of HCC. In addition, the AUC of GP73, AFP + DCP and AFP + GP73 are better than that of AFP. The clinical value of GP73, AFP + DCP, or AFP + GP73 as serological markers for HCC diagnosis needs to be addressed further in future studies.

Testing moderation in network meta-analysis with individual participant data

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Dagne, Getachew A.; Brown, C. Hendricks; Howe, George; Kellam, Sheppard G.; Liu, Lei

2016-01-01

Summary Meta-analytic methods for combining data from multiple intervention trials are commonly used to estimate the effectiveness of an intervention. They can also be extended to study comparative effectiveness, testing which of several alternative interventions is expected to have the strongest effect. This often requires network meta-analysis (NMA), which combines trials involving direct comparison of two interventions within the same trial and indirect comparisons across trials. In this paper, we extend existing network methods for main effects to examining moderator effects, allowing for tests of whether intervention effects vary for different populations or when employed in different contexts. In addition, we study how the use of individual participant data (IPD) may increase the sensitivity of NMA for detecting moderator effects, as compared to aggregate data NMA that employs study-level effect sizes in a meta-regression framework. A new network meta-analysis diagram is proposed. We also develop a generalized multilevel model for NMA that takes into account within- and between-trial heterogeneity, and can include participant-level covariates. Within this framework we present definitions of homogeneity and consistency across trials. A simulation study based on this model is used to assess effects on power to detect both main and moderator effects. Results show that power to detect moderation is substantially greater when applied to IPD as compared to study-level effects. We illustrate the use of this method by applying it to data from a classroom-based randomized study that involved two sub-trials, each comparing interventions that were contrasted with separate control groups. PMID:26841367

Combined EGFR and VEGFR versus single EGFR signaling pathways inhibition therapy for NSCLC: a systematic review and meta-analysis.

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Xinji Zhang

Full Text Available BACKGROUND: Lung cancer is a heterogeneous disease with multiple signaling pathways influencing tumor cell survival and proliferation, and it is likely that blocking only one of these pathways allows others to act as salvage or escape mechanisms for cancer cells. Whether combined inhibition therapy has greater anti-tumor activity than single inhibition therapy is a matter of debate. Hence, a meta-analysis comparing therapy inhibiting both VEGFR and EGFR signaling pathways with that inhibiting EGFR signaling pathway alone was performed. METHODOLOGY AND PRINCIPAL FINDINGS: We searched PubMed, EMBASE database and the proceedings of major conferences for relevant clinical trials. Outcomes analyzed were objective tumor response rate (ORR, progression-free survival (PFS, overall survival (OS and toxicity. Besides, subgroup analyses were performed to investigate whether the combined inhibition therapy is best performed using combination of selective agents or a single agent with multiple targets. Six trials recruiting 3,302 patients were included in the analysis. Combined inhibition therapy was associated with a 3% improvement in OS as compared with single-targeted therapy, but this difference was not statistically significant (HR, 0.97; 95% CI, 0.89-1.05; P=0.472. Patients receiving combined inhibition therapy had significant longer PFS than the group with single-targeted therapy (HR, 0.80; 95% CI, 0.67-0.95; P=0.011. There was no difference in the ORR between the groups (OR, 1.44; 95% CI, 0.95-2.18; P=0.085. Subgroup analysis revealed that combined inhibition therapy using combination regimens was associated with statistically significant improvement in both ORR and PFS. Toxicity was greater in combined inhibition therapy. CONCLUSIONS: There is no evidence to support the use of combined inhibition therapy in unselected patients with advanced NSCLC. However, given the significant advantage in ORR and PFS, combined inhibition therapy using combination

Bayesian Meta-Analysis of Coefficient Alpha

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Brannick, Michael T.; Zhang, Nanhua

2013-01-01

The current paper describes and illustrates a Bayesian approach to the meta-analysis of coefficient alpha. Alpha is the most commonly used estimate of the reliability or consistency (freedom from measurement error) for educational and psychological measures. The conventional approach to meta-analysis uses inverse variance weights to combine…

GWAMA: software for genome-wide association meta-analysis

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Mägi Reedik

2010-05-01

Full Text Available Abstract Background Despite the recent success of genome-wide association studies in identifying novel loci contributing effects to complex human traits, such as type 2 diabetes and obesity, much of the genetic component of variation in these phenotypes remains unexplained. One way to improving power to detect further novel loci is through meta-analysis of studies from the same population, increasing the sample size over any individual study. Although statistical software analysis packages incorporate routines for meta-analysis, they are ill equipped to meet the challenges of the scale and complexity of data generated in genome-wide association studies. Results We have developed flexible, open-source software for the meta-analysis of genome-wide association studies. The software incorporates a variety of error trapping facilities, and provides a range of meta-analysis summary statistics. The software is distributed with scripts that allow simple formatting of files containing the results of each association study and generate graphical summaries of genome-wide meta-analysis results. Conclusions The GWAMA (Genome-Wide Association Meta-Analysis software has been developed to perform meta-analysis of summary statistics generated from genome-wide association studies of dichotomous phenotypes or quantitative traits. Software with source files, documentation and example data files are freely available online at http://www.well.ox.ac.uk/GWAMA.

A meta-analysis of the association between mental disorders and juvenile recidivism

NARCIS (Netherlands)

Wibbelink, C.J.M.; Hoeve, M.; Stams, G.J.J.M.; Oort, F.J.

To investigate the association between mental disorders and recidivism in juveniles, a three-level meta-analysis of 20 manuscripts (17 independent studies, N = 5737 juveniles) was conducted. The study focused on internalizing disorders, externalizing disorders, and comorbid disorders (combinations

Meta-analysis of Gaussian individual patient data: Two-stage or not two-stage?

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Morris, Tim P; Fisher, David J; Kenward, Michael G; Carpenter, James R

2018-04-30

Quantitative evidence synthesis through meta-analysis is central to evidence-based medicine. For well-documented reasons, the meta-analysis of individual patient data is held in higher regard than aggregate data. With access to individual patient data, the analysis is not restricted to a "two-stage" approach (combining estimates and standard errors) but can estimate parameters of interest by fitting a single model to all of the data, a so-called "one-stage" analysis. There has been debate about the merits of one- and two-stage analysis. Arguments for one-stage analysis have typically noted that a wider range of models can be fitted and overall estimates may be more precise. The two-stage side has emphasised that the models that can be fitted in two stages are sufficient to answer the relevant questions, with less scope for mistakes because there are fewer modelling choices to be made in the two-stage approach. For Gaussian data, we consider the statistical arguments for flexibility and precision in small-sample settings. Regarding flexibility, several of the models that can be fitted only in one stage may not be of serious interest to most meta-analysis practitioners. Regarding precision, we consider fixed- and random-effects meta-analysis and see that, for a model making certain assumptions, the number of stages used to fit this model is irrelevant; the precision will be approximately equal. Meta-analysts should choose modelling assumptions carefully. Sometimes relevant models can only be fitted in one stage. Otherwise, meta-analysts are free to use whichever procedure is most convenient to fit the identified model. © 2018 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.

Trial Sequential Methods for Meta-Analysis

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Kulinskaya, Elena; Wood, John

2014-01-01

Statistical methods for sequential meta-analysis have applications also for the design of new trials. Existing methods are based on group sequential methods developed for single trials and start with the calculation of a required information size. This works satisfactorily within the framework of fixed effects meta-analysis, but conceptual…

Psychological contract breach and outcomes: Combining meta-analysis and structural equation models.

Science.gov (United States)

Topa Cantisano, Gabriela; Morales Domínguez, J Francisco; Depolo, Marco

2008-08-01

In this study, meta-analytic procedures were used to examine the relationships between psychological contract perceived breach and certain outcome variables, such as organizational commitment, job satisfaction and organizational citizenship behaviours (OCB). Our review of the literature generated 41 independent samples in which perceived breach was used as a predictor of these personal and organizational outcomes. A medium effect size (ES) for desirable outcomes (job satisfaction, organizational commitment, organizational trust, OCB and performance) was obtained (r=-.35). For undesirable outcomes (neglect in role duties and intention to leave), ES were also medium (r=.31). When comparing attitudinal (job satisfaction, organizational commitment, organizational trust) and behavioural outcomes (OCB, neglect in role duties and performance), a stronger ES was found for attitudinal (r=-.24) than for behavioural outcomes (r=-.11). Potential moderator variables were examined, and it was found that they explained only a percentage of variability of primary studies. Structural equation analysis of the pooled meta-analytical correlation matrix indicated that the relationships of perceived breach with satisfaction, OCB, intention to leave and performance are fully mediated by organizational trust and commitment. Results are discussed in order to suggest theoretical and empirical implications.

META-ANALYSIS: THE WAY FORWARD IN MEDICAL DISCOVERY

African Journals Online (AJOL)

data, and (6) report the results. Define the Research Question. A meta-analysis begins with a question. Common questions addressed in meta-analyses are whether one. META-ANALYSIS: THE WAY FORWARD IN MEDICAL DISCOVERY. Akinyemi J.O. MSc (Medical Statistics), B Tech (Comp. Sc.) Correspondence:.

A Meta-Analysis for Postoperative Complications in Tibial Plafond Fracture: Open Reduction and Internal Fixation Versus Limited Internal Fixation Combined With External Fixator.

Science.gov (United States)

Wang, Dong; Xiang, Jian-Ping; Chen, Xiao-Hu; Zhu, Qing-Tang

2015-01-01

The treatment of tibial plafond fractures is challenging to foot and ankle surgeons. Open reduction and internal fixation and limited internal fixation combined with an external fixator are 2 of the most commonly used methods of tibial plafond fracture repair. However, conclusions regarding the superior choice remain controversial. The present meta-analysis aimed to quantitatively compare the postoperative complications between open reduction and internal fixation and limited internal fixation combined with an external fixator for tibial plafond fractures. Nine studies with 498 fractures in 494 patients were included in the present study. The meta-analysis found no significant differences in bone healing complications (risk ratio [RR] 1.17, 95% confidence interval [CI] 0.68 to 2.01, p = .58], nonunion (RR 1.09, 95% CI 0.51 to 2.36, p = .82), malunion or delayed union (RR 1.24, 95% CI 0.57 to 2.69, p = .59), superficial (RR 1.56, 95% CI 0.43 to 5.61, p = .50) and deep (RR 1.89, 95% CI 0.62 to 5.80) infections, arthritis symptoms (RR 1.20, 95% CI 0.92 to 1.58, p = .18), or chronic osteomyelitis (RR 0.31, 95% CI 0.05 to 1.84, p = .20) between the 2 groups. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

Meta-Analysis in Stata Using Gllamm

Science.gov (United States)

Bagos, Pantelis G.

2015-01-01

There are several user-written programs for performing meta-analysis in Stata (Stata Statistical Software: College Station, TX: Stata Corp LP). These include metan, metareg, mvmeta, and glst. However, there are several cases for which these programs do not suffice. For instance, there is no software for performing univariate meta-analysis with…

Combined versus single application of tranexamic acid in total knee and hip arthroplasty: A meta-analysis of randomized controlled trials.

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Peng Zhang, M M; Jifeng Li, M M; Xiao Wang, M M

2017-07-01

To compare the efficacy and safety of the combined application of both intravenous and topical tranexamic acid versus the single use of either application in patients with total knee and hip arthroplasty. Potentially relevant studies were identified from electronic databases including Medline, PubMed, Embase, ScienceDirect and the Cochrane Library. Patients undergoing primary total knee and hip arthroplasty were included in our studies, with an experimental group that received combined intravenous and topical application of tranexamic acid and a control group that received a single application of tranexamic acid or normal saline. The primary outcomes were total blood loss, hemoglobin decline and transfusion requirements. The secondary outcomes were length of stay, operation time and tranexamic acid-related adverse effects, such as superficial infection, deep vein thrombosis or pulmonary embolism. Modified Jadad scores were used to assess the quality of the included randomized controlled trials (RCTs). The data was pooled using RevMan 5.3. After testing for heterogeneity across studies, the data were aggregated using random-effects modeling when appropriate. We have registered the trial at http://www.researchregistry.com. Six RCTs that included 704 patients met the inclusion criteria. The present meta-analysis indicated significant differences existed in the total blood loss (MD = -134.65, 95% CI: -191.66 to -77.64, P tranexamic acid in total knee and hip arthroplasty was associated with significantly reduced total blood loss, postoperative hemoglobin decline, drainage volume, and transfusion requirements. Based on the limitations of current meta-analysis, well-designed, high-quality RCTs with long-term follow-up are still required. Copyright © 2017 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

Effect of nutritional supplement combined with exercise intervention on sarcopenia in the elderly: A meta-analysis

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Dan Luo

2017-10-01

Full Text Available Objectives: This systematic review was conducted to explore whether nutritional supplement can improve the benefits of exercise intervention on sarcopenia in the elderly. Methods: Databases, including PubMed, Embase, Cochrane Library, Web of Science, CINAHL, CBM, CNKI, WANFANG, and VIP, were searched. All related papers with randomized controlled trials (RCT methodology that were included in the databases from inception to 19 July 2016 were selected for the study. The tool “assessing risk of bias” from Cochrane Handbook 5.10 was used to evaluate the quality of included papers. A meta-analysis of eligible studies was performed using Stata12.0. Data that we were unable to convene or merge were subjected to descriptive analysis. Results: Six trials were included in our study, which included 429 elderly patients with sarcopenia. The overall methodological quality of the trials was moderate. Compared with the exercise group, patients who were given nutritional supplements gained a bigger boost in fat-free mass (standard mean difference (SMD = 5.78, 95% CI: 5.17 to 6.40, P = 0.000 and muscle mass (SMD = 2.048, 95% CI: 0.907 to 3.189, P = 0.000, as well as showed enhancement of keen extension strength (SMD = 1.08, 95% CI: 0.71 to 1.45, P = 0.000 and usual walk speed (SMD = 0.570, 95% CI: 0.19 to 0.95, P = 0.003. Conclusion: Nutritional supplementation may magnify the effect of exercise intervention on sarcopenia elderly in terms of muscle mass, muscle strength, and physical performance. Inconsistencies were present among research studies. More robust studies are needed to determine the most suitable type of nutrient and target population and to explore the actual role of combined intervention in managing sarcopenia in the elderly. Keywords: Sarcopenia, Exercise, Nutritional status, Meta-analysis

Using structural equation modeling for network meta-analysis.

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Tu, Yu-Kang; Wu, Yun-Chun

2017-07-14

Network meta-analysis overcomes the limitations of traditional pair-wise meta-analysis by incorporating all available evidence into a general statistical framework for simultaneous comparisons of several treatments. Currently, network meta-analyses are undertaken either within the Bayesian hierarchical linear models or frequentist generalized linear mixed models. Structural equation modeling (SEM) is a statistical method originally developed for modeling causal relations among observed and latent variables. As random effect is explicitly modeled as a latent variable in SEM, it is very flexible for analysts to specify complex random effect structure and to make linear and nonlinear constraints on parameters. The aim of this article is to show how to undertake a network meta-analysis within the statistical framework of SEM. We used an example dataset to demonstrate the standard fixed and random effect network meta-analysis models can be easily implemented in SEM. It contains results of 26 studies that directly compared three treatment groups A, B and C for prevention of first bleeding in patients with liver cirrhosis. We also showed that a new approach to network meta-analysis based on the technique of unrestricted weighted least squares (UWLS) method can also be undertaken using SEM. For both the fixed and random effect network meta-analysis, SEM yielded similar coefficients and confidence intervals to those reported in the previous literature. The point estimates of two UWLS models were identical to those in the fixed effect model but the confidence intervals were greater. This is consistent with results from the traditional pairwise meta-analyses. Comparing to UWLS model with common variance adjusted factor, UWLS model with unique variance adjusted factor has greater confidence intervals when the heterogeneity was larger in the pairwise comparison. The UWLS model with unique variance adjusted factor reflects the difference in heterogeneity within each comparison

Meta-Analysis of Coefficient Alpha

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Rodriguez, Michael C.; Maeda, Yukiko

2006-01-01

The meta-analysis of coefficient alpha across many studies is becoming more common in psychology by a methodology labeled reliability generalization. Existing reliability generalization studies have not used the sampling distribution of coefficient alpha for precision weighting and other common meta-analytic procedures. A framework is provided for…

Data analysis with the DIANA meta-scheduling approach

International Nuclear Information System (INIS)

Anjum, A; McClatchey, R; Willers, I

2008-01-01

The concepts, design and evaluation of the Data Intensive and Network Aware (DIANA) meta-scheduling approach for solving the challenges of data analysis being faced by CERN experiments are discussed in this paper. Our results suggest that data analysis can be made robust by employing fault tolerant and decentralized meta-scheduling algorithms supported in our DIANA meta-scheduler. The DIANA meta-scheduler supports data intensive bulk scheduling, is network aware and follows a policy centric meta-scheduling. In this paper, we demonstrate that a decentralized and dynamic meta-scheduling approach is an effective strategy to cope with increasing numbers of users, jobs and datasets. We present 'quality of service' related statistics for physics analysis through the application of a policy centric fair-share scheduling model. The DIANA meta-schedulers create a peer-to-peer hierarchy of schedulers to accomplish resource management that changes with evolving loads and is dynamic and adapts to the volatile nature of the resources

Multivariate meta-analysis: a robust approach based on the theory of U-statistic.

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Ma, Yan; Mazumdar, Madhu

2011-10-30

Meta-analysis is the methodology for combining findings from similar research studies asking the same question. When the question of interest involves multiple outcomes, multivariate meta-analysis is used to synthesize the outcomes simultaneously taking into account the correlation between the outcomes. Likelihood-based approaches, in particular restricted maximum likelihood (REML) method, are commonly utilized in this context. REML assumes a multivariate normal distribution for the random-effects model. This assumption is difficult to verify, especially for meta-analysis with small number of component studies. The use of REML also requires iterative estimation between parameters, needing moderately high computation time, especially when the dimension of outcomes is large. A multivariate method of moments (MMM) is available and is shown to perform equally well to REML. However, there is a lack of information on the performance of these two methods when the true data distribution is far from normality. In this paper, we propose a new nonparametric and non-iterative method for multivariate meta-analysis on the basis of the theory of U-statistic and compare the properties of these three procedures under both normal and skewed data through simulation studies. It is shown that the effect on estimates from REML because of non-normal data distribution is marginal and that the estimates from MMM and U-statistic-based approaches are very similar. Therefore, we conclude that for performing multivariate meta-analysis, the U-statistic estimation procedure is a viable alternative to REML and MMM. Easy implementation of all three methods are illustrated by their application to data from two published meta-analysis from the fields of hip fracture and periodontal disease. We discuss ideas for future research based on U-statistic for testing significance of between-study heterogeneity and for extending the work to meta-regression setting. Copyright © 2011 John Wiley & Sons, Ltd.

Body mass index and risk of BPH: a meta-analysis.

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Wang, S; Mao, Q; Lin, Y; Wu, J; Wang, X; Zheng, X; Xie, L

2012-09-01

Epidemiological studies have reported conflicting results relating obesity to BPH. A meta-analysis of cohort and case-control studies was conducted to pool the risk estimates of the association between obesity and BPH. Eligible studies were retrieved by both computer searches and review of references. We analyzed abstracted data with random effects models to obtain the summary risk estimates. Dose-response meta-analysis was performed for studies reporting categorical risk estimates for a series of exposure levels. A total of 19 studies met the inclusion criteria of the meta-analysis. Positive association with body mass index (BMI) was observed in BPH and lower urinary tract symptoms (LUTS) combined group (odds ratio=1.27, 95% confidence intervals 1.05-1.53). In subgroup analysis, BMI exhibited a positive dose-response relationship with BPH/LUTS in population-based case-control studies and a marginal positive association was observed between risk of BPH and increased BMI. However, no association between BPH/LUTS and BMI was observed in other subgroups stratified by study design, geographical region or primary outcome. The overall current literatures suggested that BMI was associated with increased risk of BPH. Further efforts should be made to confirm these findings and clarify the underlying biological mechanisms.

Multiple Sclerosis Increases Fracture Risk: A Meta-Analysis

Directory of Open Access Journals (Sweden)

Guixian Dong

2015-01-01

Full Text Available Purpose. The association between multiple sclerosis (MS and fracture risk has been reported, but results of previous studies remain controversial and ambiguous. To assess the association between MS and fracture risk, a meta-analysis was performed. Method. Based on comprehensive searches of the PubMed, Embase, and Web of Science, we identified outcome data from all articles estimating the association between MS and fracture risk. The pooled risk ratios (RRs with 95% confidence intervals (CIs were calculated. Results. A significant association between MS and fracture risk was found. This result remained statistically significant when the adjusted RRs were combined. Subgroup analysis stratified by the site of fracture suggested significant associations between MS and tibia fracture risk, femur fracture risk, hip fracture risk, pelvis fracture risk, vertebrae fracture risk, and humerus fracture risk. In the subgroup analysis by gender, female MS patients had increased fracture risk. When stratified by history of drug use, use of antidepressants, hypnotics/anxiolytics, anticonvulsants, and glucocorticoids increased the risk of fracture risk in MS patients. Conclusions. This meta-analysis demonstrated that MS was significantly associated with fracture risk.

Internal fixation of mandibular angle fractures: a meta-analysis.

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Regev, Eran; Shiff, Jacob S; Kiss, Alex; Fialkov, Jeffrey A

2010-06-01

The degree of rigidity of internal fixation required for the treatment of mandibular angle fractures has long been at the center of debate in the literature. A statistical comparison between rigid fixation and monocortical fixation has been difficult because of multiple terms, definitions, and technical variations. The purpose of this study was to use the meta-analysis tool to combine information from multiple studies and to compare complication rates for different fixation methods. An English language literature search was conducted for articles on mandibular angle fractures. Information was collected on four variables of interest: compression/noncompression technique, monocortical/bicortical screws, number of plates, and location of plates. Five outcome rates were analyzed: infection, reoperation, hardware removal, malunion, and nonunion. Meta-analyses were run using Comprehensive Meta Analysis, version 2.2.03. Twenty-four studies with relevant data on the variables and outcomes of interest met the inclusion criteria. Significantly higher rates of infection, reoperation, and hardware removal were found for compression compared with noncompression, two plates compared with one plate, and for plates located on both the inferior and superior borders as compared with superior or inferior only. There were also significantly higher infection rates for bicortical screws compared with monocortical screws and higher malunion rates for compression compared with noncompression plating techniques. The results of this meta-analysis found lower complication rates with the use of noncompression, monocortical, and single-plate fixation, supporting the trend toward a single, superiorly placed, monocortical miniplate for fixation of mandibular angle fractures.

Is Huachansu Beneficial in Treating Advanced Non-Small-Cell Lung Cancer? Evidence from a Meta-Analysis of Its Efficacy Combined with Chemotherapy

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Bingduo Zhou

2015-01-01

Full Text Available Background. Huachansu, the sterilized water extract of Bufo bufo gargarizans toad skin, is used in China to alleviate the side-effects and enhance the therapeutic effect of chemotherapy in advanced non-small-cell lung cancer (NSCLC. We conducted a meta-analysis to assess Huachansu’s efficacy. Methods. We extensively searched electronic databases (CENTRAL, EMBASE, MEDLINE, CBM, Cochrane Library, CNKI, CEBM, WFDP, CSCD, CSTD, and IPA for randomized controlled trials containing Huachansu plus chemotherapy as the test group and chemotherapy as the control group. Seventeen trials were selected based on the selection criteria. The pooled relative ratio (RR of indicators with 95% confidence interval (95% CI was calculated for efficacy evaluation. Results. The meta-analysis demonstrated a statistically significant improvement in objective tumor response, one-year survival, Karnofsky performance status, pain relief, and alleviation of severe side-effects (nausea and vomiting, leukocytopenia in the test group as compared to the control group, but no significant difference in thrombocytopenia. Conclusions. This study demonstrated the efficacy of Huachansu combined with chemotherapy in the treatment of advanced NSCLC. However, limitations exist and high-quality trials are needed for further verification.

MetaSeq: privacy preserving meta-analysis of sequencing-based association studies.

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Singh, Angad Pal; Zafer, Samreen; Pe'er, Itsik

2013-01-01

Human genetics recently transitioned from GWAS to studies based on NGS data. For GWAS, small effects dictated large sample sizes, typically made possible through meta-analysis by exchanging summary statistics across consortia. NGS studies groupwise-test for association of multiple potentially-causal alleles along each gene. They are subject to similar power constraints and therefore likely to resort to meta-analysis as well. The problem arises when considering privacy of the genetic information during the data-exchange process. Many scoring schemes for NGS association rely on the frequency of each variant thus requiring the exchange of identity of the sequenced variant. As such variants are often rare, potentially revealing the identity of their carriers and jeopardizing privacy. We have thus developed MetaSeq, a protocol for meta-analysis of genome-wide sequencing data by multiple collaborating parties, scoring association for rare variants pooled per gene across all parties. We tackle the challenge of tallying frequency counts of rare, sequenced alleles, for metaanalysis of sequencing data without disclosing the allele identity and counts, thereby protecting sample identity. This apparent paradoxical exchange of information is achieved through cryptographic means. The key idea is that parties encrypt identity of genes and variants. When they transfer information about frequency counts in cases and controls, the exchanged data does not convey the identity of a mutation and therefore does not expose carrier identity. The exchange relies on a 3rd party, trusted to follow the protocol although not trusted to learn about the raw data. We show applicability of this method to publicly available exome-sequencing data from multiple studies, simulating phenotypic information for powerful meta-analysis. The MetaSeq software is publicly available as open source.

LABA/LAMA combinations versus LAMA monotherapy or LABA/ICS in COPD: a systematic review and meta-analysis

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Rodrigo GJ

2017-03-01

Full Text Available Gustavo J Rodrigo,1 David Price,2,3 Antonio Anzueto,4,5 Dave Singh,6 Pablo Altman,7 Giovanni Bader,8 Francesco Patalano,8 Robert Fogel,7 Konstantinos Kostikas8 1Departamento de Emergencia, Hospital Central de las Fuerzas Armadas, Montevideo, Uruguay; 2Academic Primary Care, Division of Applied Health Sciences, University of Aberdeen, Aberdeen, Scotland, UK; 3Observational and Pragmatic Research Institute, Singapore; 4University of Texas Health Science Center, 5South Texas Veterans Health Care System, San Antonio, TX, USA; 6Medicines Evaluation Unit, National Institute for Health Research Respiratory and Allergy Clinical Research Facility, University Hospital of South Manchester NHS Foundation Trust, University of Manchester, Manchester, England, UK; 7Novartis Pharmaceuticals Corporation, East Hanover, NJ, USA; 8Novartis Pharma AG, Basel, Switzerland Background: Randomized controlled trials (RCTs indicate that long-acting bronchodilator combinations, such as β2-agonist (LABA/muscarinic antagonist (LAMA, have favorable efficacy compared with commonly used COPD treatments. The objective of this analysis was to compare the efficacy and safety of LABA/LAMA with LAMA or LABA/inhaled corticosteroid (ICS in adults with stable moderate-to-very-severe COPD. Methods: This systematic review and meta-analysis (PubMed/MEDLINE, Embase, Cochrane Library and clinical trial/manufacturer databases included RCTs comparing ≥12 weeks’ LABA/LAMA treatment with LAMA and/or LABA/ICS (approved doses only. Eligible studies were independently selected by two authors using predefined data fields; the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. Results: Eighteen studies (23 trials were eligible (N=20,185. LABA/LAMA significantly improved trough forced expiratory volume in 1 second (FEV1 from baseline to week 12 versus both LAMA and LABA/ICS (0.07 L and 0.08 L, P<0.0001, with patients more likely to achieve clinically

Multivariate Methods for Meta-Analysis of Genetic Association Studies.

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Dimou, Niki L; Pantavou, Katerina G; Braliou, Georgia G; Bagos, Pantelis G

2018-01-01

Multivariate meta-analysis of genetic association studies and genome-wide association studies has received a remarkable attention as it improves the precision of the analysis. Here, we review, summarize and present in a unified framework methods for multivariate meta-analysis of genetic association studies and genome-wide association studies. Starting with the statistical methods used for robust analysis and genetic model selection, we present in brief univariate methods for meta-analysis and we then scrutinize multivariate methodologies. Multivariate models of meta-analysis for a single gene-disease association studies, including models for haplotype association studies, multiple linked polymorphisms and multiple outcomes are discussed. The popular Mendelian randomization approach and special cases of meta-analysis addressing issues such as the assumption of the mode of inheritance, deviation from Hardy-Weinberg Equilibrium and gene-environment interactions are also presented. All available methods are enriched with practical applications and methodologies that could be developed in the future are discussed. Links for all available software implementing multivariate meta-analysis methods are also provided.

a meta-analysis

Indian Academy of Sciences (India)

Chrissa G. Tsiara

2018-03-13

Mar 13, 2018 ... a meta-analysis of case–control studies was conducted. Univariate and ...... recent hepatitis C virus: potential benefit for ribavirin use in. HCV/HIV ... C/G polymorphism in breast pathologies and in HIV-infected patients.

Combined effects of aerobic exercise and diet on lipids and lipoproteins in overweight and obese adults: a meta-analysis

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This study used the aggregate data meta-analytic approach to determine the combined effects of aerobic exercise and diet on lipids and lipoproteins in overweight and obese adults. Twelve studies representing 859 men and women (443 intervention, 416 control) were included. Using random-effects models...

Meta-analysis of Huangqi injection for the adjunctive therapy of aplastic anemia

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Zhu, Changtai; Gao, Yulu; Jiang, Ting; Hao, Cao; Gao, Zongshuai; Sun, Yongning

2015-01-01

Aplastic anemia therapy remains difficult, due to lack of effective treatment regimens. In recent years, Huangqi injection for the adjunctive therapy of aplastic anemia has been reported in many clinical trials. Considering that Huangqi injection may be a novel approach to aplastic anemia treatment, we conducted a meta-analysis of clinical controlled trials to assess the clinical value of Huangqi injection in the treatment of aplastic anemia. We searched the Chinese Biomedical Literature Database (CBM), China National Knowledge Infrastructure (CNKI), Chinese Scientific Journals Full-text Database (VIP), Wanfang Database, PubMed and EMBASE database to collect the data about the trials of Huangqi injection combined with androgens for treating aplastic anemia. A total of ten studies involving 720 patients with aplastic anemia were included in this study. The meta-analysis showed significant increases in the pool effectiveness rate, white blood cells (WBC), haematoglobin (Hb), platelets (PLT), and reticulocytes (Ret) between the experimental group versus the control group. No severe side effects were found in this study. However, the lower Jadad scores and asymmetric funnel plot degrades the validity of the meta-analysis as the clinical evidence. Therefore, Huangqi injection may significantly enhance the efficacy of androgens for aplastic anemia, suggesting that the novel approach of Chinese traditional medicine combined with Western medicine is promising. The exact outcome required confirmation with rigorously well-designed multi-center trials. PMID:26379817

Marital status integration and suicide: A meta-analysis and meta-regression.

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Kyung-Sook, Woo; SangSoo, Shin; Sangjin, Shin; Young-Jeon, Shin

2018-01-01

Marital status is an index of the phenomenon of social integration within social structures and has long been identified as an important predictor suicide. However, previous meta-analyses have focused only on a particular marital status, or not sufficiently explored moderators. A meta-analysis of observational studies was conducted to explore the relationships between marital status and suicide and to understand the important moderating factors in this association. Electronic databases were searched to identify studies conducted between January 1, 2000 and June 30, 2016. We performed a meta-analysis, subgroup analysis, and meta-regression of 170 suicide risk estimates from 36 publications. Using random effects model with adjustment for covariates, the study found that the suicide risk for non-married versus married was OR = 1.92 (95% CI: 1.75-2.12). The suicide risk was higher for non-married individuals aged analysis by gender, non-married men exhibited a greater risk of suicide than their married counterparts in all sub-analyses, but women aged 65 years or older showed no significant association between marital status and suicide. The suicide risk in divorced individuals was higher than for non-married individuals in both men and women. The meta-regression showed that gender, age, and sample size affected between-study variation. The results of the study indicated that non-married individuals have an aggregate higher suicide risk than married ones. In addition, gender and age were confirmed as important moderating factors in the relationship between marital status and suicide. Copyright © 2017 Elsevier Ltd. All rights reserved.

Individual and combined effects of multiple global change drivers on terrestrial phosphorus pools: A meta-analysis.

Science.gov (United States)

Yue, Kai; Yang, Wanqin; Peng, Yan; Peng, Changhui; Tan, Bo; Xu, Zhenfeng; Zhang, Li; Ni, Xiangyin; Zhou, Wei; Wu, Fuzhong

2018-07-15

Human activity-induced global change drivers have dramatically changed terrestrial phosphorus (P) dynamics. However, our understanding of the interactive effects of multiple global change drivers on terrestrial P pools remains elusive, limiting their incorporation into ecological and biogeochemical models. We conducted a meta-analysis using 1751 observations extracted from 283 published articles to evaluate the individual, combined, and interactive effects of elevated CO 2 , warming, N addition, P addition, increased rainfall, and drought on P pools of plant (at both single-plant and plant-community levels), soil and microbial biomass. Our results suggested that (1) terrestrial P pools showed the most sensitive responses to the individual effects of warming and P addition; (2) P pools were consistently stimulated by P addition alone or in combination with simultaneous N addition; (3) environmental and experimental setting factors such as ecosystem type, climate, and latitude could significantly influence both the individual and combined effects; and (4) the interactive effects of two-driver pairs across multiple global change drivers are more likely to be additive rather than synergistic or antagonistic. Our findings highlighting the importance of additive interactive effects among multiple global change drivers on terrestrial P pools would be useful for incorporating P as controls on ecological processes such as photosynthesis and plant growth into ecosystem models used to analyze effects of multiple drivers under future global change. Copyright © 2018 Elsevier B.V. All rights reserved.

Online Open Neuroimaging Mass Meta-Analysis with a Wiki

DEFF Research Database (Denmark)

Nielsen, Finn Arup; Kempton, Matthew J.; Williams, Steven C. R.

2015-01-01

We describe a system for meta-analysis where a wiki stores numerical data in a simple comma-separated values format and a web service performs the numerical statistical computation. We initially apply the system on multiple meta-analyses of structural neuroimaging data results. The described system...... allows for mass meta-analysis, e.g., meta-analysis across multiple brain regions and multiple mental disorders providing an overview of important relationships and their uncertainties in a collaborative environment....

Meta-analysis in clinical trials revisited.

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DerSimonian, Rebecca; Laird, Nan

2015-11-01

In this paper, we revisit a 1986 article we published in this Journal, Meta-Analysis in Clinical Trials, where we introduced a random-effects model to summarize the evidence about treatment efficacy from a number of related clinical trials. Because of its simplicity and ease of implementation, our approach has been widely used (with more than 12,000 citations to date) and the "DerSimonian and Laird method" is now often referred to as the 'standard approach' or a 'popular' method for meta-analysis in medical and clinical research. The method is especially useful for providing an overall effect estimate and for characterizing the heterogeneity of effects across a series of studies. Here, we review the background that led to the original 1986 article, briefly describe the random-effects approach for meta-analysis, explore its use in various settings and trends over time and recommend a refinement to the method using a robust variance estimator for testing overall effect. We conclude with a discussion of repurposing the method for Big Data meta-analysis and Genome Wide Association Studies for studying the importance of genetic variants in complex diseases. Published by Elsevier Inc.

Evaluating the Quality of Evidence from a Network Meta-Analysis

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Salanti, Georgia; Del Giovane, Cinzia; Chaimani, Anna; Caldwell, Deborah M.; Higgins, Julian P. T.

2014-01-01

Systematic reviews that collate data about the relative effects of multiple interventions via network meta-analysis are highly informative for decision-making purposes. A network meta-analysis provides two types of findings for a specific outcome: the relative treatment effect for all pairwise comparisons, and a ranking of the treatments. It is important to consider the confidence with which these two types of results can enable clinicians, policy makers and patients to make informed decisions. We propose an approach to determining confidence in the output of a network meta-analysis. Our proposed approach is based on methodology developed by the Grading of Recommendations Assessment, Development and Evaluation (GRADE) Working Group for pairwise meta-analyses. The suggested framework for evaluating a network meta-analysis acknowledges (i) the key role of indirect comparisons (ii) the contributions of each piece of direct evidence to the network meta-analysis estimates of effect size; (iii) the importance of the transitivity assumption to the validity of network meta-analysis; and (iv) the possibility of disagreement between direct evidence and indirect evidence. We apply our proposed strategy to a systematic review comparing topical antibiotics without steroids for chronically discharging ears with underlying eardrum perforations. The proposed framework can be used to determine confidence in the results from a network meta-analysis. Judgements about evidence from a network meta-analysis can be different from those made about evidence from pairwise meta-analyses. PMID:24992266

Beta-binomial model for meta-analysis of odds ratios.

Science.gov (United States)

Bakbergenuly, Ilyas; Kulinskaya, Elena

2017-05-20

In meta-analysis of odds ratios (ORs), heterogeneity between the studies is usually modelled via the additive random effects model (REM). An alternative, multiplicative REM for ORs uses overdispersion. The multiplicative factor in this overdispersion model (ODM) can be interpreted as an intra-class correlation (ICC) parameter. This model naturally arises when the probabilities of an event in one or both arms of a comparative study are themselves beta-distributed, resulting in beta-binomial distributions. We propose two new estimators of the ICC for meta-analysis in this setting. One is based on the inverted Breslow-Day test, and the other on the improved gamma approximation by Kulinskaya and Dollinger (2015, p. 26) to the distribution of Cochran's Q. The performance of these and several other estimators of ICC on bias and coverage is studied by simulation. Additionally, the Mantel-Haenszel approach to estimation of ORs is extended to the beta-binomial model, and we study performance of various ICC estimators when used in the Mantel-Haenszel or the inverse-variance method to combine ORs in meta-analysis. The results of the simulations show that the improved gamma-based estimator of ICC is superior for small sample sizes, and the Breslow-Day-based estimator is the best for n⩾100. The Mantel-Haenszel-based estimator of OR is very biased and is not recommended. The inverse-variance approach is also somewhat biased for ORs≠1, but this bias is not very large in practical settings. Developed methods and R programs, provided in the Web Appendix, make the beta-binomial model a feasible alternative to the standard REM for meta-analysis of ORs. © 2017 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd. © 2017 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.

Radical Cystectomy Compared to Combined Modality Treatment for Muscle-Invasive Bladder Cancer: A Systematic Review and Meta-Analysis

International Nuclear Information System (INIS)

Vashistha, Vishal; Wang, Hanzhang; Mazzone, Andrew; Liss, Michael A.; Svatek, Robert S.; Schleicher, Mary; Kaushik, Dharam

2017-01-01

Purpose: To perform a comprehensive comparison of overall survival (OS), disease-specific survival (DSS), progression-free survival (PFS), and treatment-related complications between radical cystectomy (RC) and combined modality treatment (CMT—radiation therapy, concurrent chemotherapy, and maximal transurethral resection of bladder tumor) in the setting of muscle-invasive bladder cancer. Methods and Materials: We searched 7 databases (PubMed, Scopus, EMBASE, Proquest, CINAHL, and (ClinicalTrials.gov)) for randomized, controlled trials and prospective and retrospective studies directly comparing RC with CMT from database inception to March 2016. We conducted meta-analyses evaluating OS, DSS, and PFS with hazard ratios (HRs) and 95% confidence intervals (CIs). Results: Nineteen studies evaluating 12,380 subjects were selected. For the 8 studies encompassing 9554 subjects eligible for meta-analyses, we found no difference in OS at 5 years (HR 0.96, favoring CMT, 95% CI 0.72-1.29; P=.778) or 10 years (HR 1.02, favoring cystectomy, 95% CI 0.73-1.42; P=.905). No difference was observed in DSS at 5 years (HR 0.83, favoring radiation, 95% CI 0.54-1.28; P=.390) or 10 years (HR 1.17, favoring cystectomy, 95% CI 0.89-1.55; P=.264), or PFS at 10 years (HR 0.85, favoring CMT, 95% CI 0.43-1.67; P=.639). The cystectomy arms had higher rates of early major complications, whereas rates of minor complications were similar between the 2 treatments. Conclusion: Current meta-analysis reveals no differences in OS, DSS, or PFS between RC and CMT. Further randomized, controlled trials are necessary to identify the optimal treatment for specific patients.

Radical Cystectomy Compared to Combined Modality Treatment for Muscle-Invasive Bladder Cancer: A Systematic Review and Meta-Analysis

Energy Technology Data Exchange (ETDEWEB)

Vashistha, Vishal [Department of Internal Medicine, Cleveland Clinic Foundation, Cleveland, Ohio (United States); Wang, Hanzhang [Department of Urology, University of Texas Health Science Center at San Antonio, San Antonio, Texas (United States); Mazzone, Andrew [Rush Medical College, Rush University Medical Center, Chicago, Illinois (United States); Liss, Michael A.; Svatek, Robert S. [Department of Urology, University of Texas Health Science Center at San Antonio, San Antonio, Texas (United States); Schleicher, Mary [Department of Internal Medicine, Cleveland Clinic Foundation, Cleveland, Ohio (United States); Kaushik, Dharam, E-mail: Kaushik@uthscsa.edu [Department of Urology, University of Texas Health Science Center at San Antonio, San Antonio, Texas (United States)

2017-04-01

Purpose: To perform a comprehensive comparison of overall survival (OS), disease-specific survival (DSS), progression-free survival (PFS), and treatment-related complications between radical cystectomy (RC) and combined modality treatment (CMT—radiation therapy, concurrent chemotherapy, and maximal transurethral resection of bladder tumor) in the setting of muscle-invasive bladder cancer. Methods and Materials: We searched 7 databases (PubMed, Scopus, EMBASE, Proquest, CINAHL, and (ClinicalTrials.gov)) for randomized, controlled trials and prospective and retrospective studies directly comparing RC with CMT from database inception to March 2016. We conducted meta-analyses evaluating OS, DSS, and PFS with hazard ratios (HRs) and 95% confidence intervals (CIs). Results: Nineteen studies evaluating 12,380 subjects were selected. For the 8 studies encompassing 9554 subjects eligible for meta-analyses, we found no difference in OS at 5 years (HR 0.96, favoring CMT, 95% CI 0.72-1.29; P=.778) or 10 years (HR 1.02, favoring cystectomy, 95% CI 0.73-1.42; P=.905). No difference was observed in DSS at 5 years (HR 0.83, favoring radiation, 95% CI 0.54-1.28; P=.390) or 10 years (HR 1.17, favoring cystectomy, 95% CI 0.89-1.55; P=.264), or PFS at 10 years (HR 0.85, favoring CMT, 95% CI 0.43-1.67; P=.639). The cystectomy arms had higher rates of early major complications, whereas rates of minor complications were similar between the 2 treatments. Conclusion: Current meta-analysis reveals no differences in OS, DSS, or PFS between RC and CMT. Further randomized, controlled trials are necessary to identify the optimal treatment for specific patients.

Can statistic adjustment of OR minimize the potential confounding bias for meta-analysis of case-control study? A secondary data analysis.

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Liu, Tianyi; Nie, Xiaolu; Wu, Zehao; Zhang, Ying; Feng, Guoshuang; Cai, Siyu; Lv, Yaqi; Peng, Xiaoxia

2017-12-29

Different confounder adjustment strategies were used to estimate odds ratios (ORs) in case-control study, i.e. how many confounders original studies adjusted and what the variables are. This secondary data analysis is aimed to detect whether there are potential biases caused by difference of confounding factor adjustment strategies in case-control study, and whether such bias would impact the summary effect size of meta-analysis. We included all meta-analyses that focused on the association between breast cancer and passive smoking among non-smoking women, as well as each original case-control studies included in these meta-analyses. The relative deviations (RDs) of each original study were calculated to detect how magnitude the adjustment would impact the estimation of ORs, compared with crude ORs. At the same time, a scatter diagram was sketched to describe the distribution of adjusted ORs with different number of adjusted confounders. Substantial inconsistency existed in meta-analysis of case-control studies, which would influence the precision of the summary effect size. First, mixed unadjusted and adjusted ORs were used to combine individual OR in majority of meta-analysis. Second, original studies with different adjustment strategies of confounders were combined, i.e. the number of adjusted confounders and different factors being adjusted in each original study. Third, adjustment did not make the effect size of original studies trend to constringency, which suggested that model fitting might have failed to correct the systematic error caused by confounding. The heterogeneity of confounder adjustment strategies in case-control studies may lead to further bias for summary effect size in meta-analyses, especially for weak or medium associations so that the direction of causal inference would be even reversed. Therefore, further methodological researches are needed, referring to the assessment of confounder adjustment strategies, as well as how to take this kind

Usefulness of {sup 18}F-FDG PET, combined FDG-PET/CT and EUS in diagnosing primary pancreatic carcinoma: A meta-analysis

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Tang Shuang [Department of Nuclear Medicine, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127 (China); Huang Gang, E-mail: huang2802@163.com [Department of Nuclear Medicine, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127 (China); Liu Jianjun [Department of Nuclear Medicine, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127 (China); Liu Tao [Department of Orthopedics, Soochow University, Suzhou (China); Treven, Lyndal [Faculty of Public Health, University of Sydney, Sydney (Australia); Song Saoli; Zhang Chenpeng; Pan Lingling [Department of Nuclear Medicine, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127 (China); Zhang Ting [Department of Anesthesiology, Renji Hospital, Shanghai (China)

2011-04-15

The aim was to evaluate the diagnostic value of {sup 18}F-fluorodeoxyglucose-positron emission tomography ({sup 18}F-FDG PET), combined {sup 18}F-fluorodeoxyglucose-positron emission tomography/computed tomography ({sup 18}F-FDG PET/CT) and endoscopic ultrasonography (EUS) in diagnosing patients with pancreatic carcinoma. MEDLINE, EMBASE, Cochrane library and some other databases, from January 1966 to April 2009, were searched for initial studies. All the studies published in English or Chinese relating to the diagnostic value of {sup 18}F-FDG PET, PET/CT and EUS for patients with pancreatic cancer were collected. Methodological quality was assessed. The statistic software called 'Meta-Disc 1.4' was used for data analysis. Results: 51 studies were included in this meta-analysis. The pooled sensitivity estimate for combined PET/CT (90.1%) was significantly higher than PET (88.4%) and EUS (81.2%). The pooled specificity estimate for EUS (93.2%) was significantly higher than PET (83.1%) and PET/CT (80.1%). The pooled DOR estimate for EUS (49.774) was significantly higher than PET (32.778) and PET/CT (27.105). SROC curves for PET/CT and EUS showed a little better diagnostic accuracy than PET alone. For PET alone, when interpreted the results with knowledge of other imaging tests, its sensitivity (89.4%) and specificity (80.1%) were closer to PET/CT. For EUS, its diagnostic value decreased in differentiating pancreatic cancer for patients with chronic pancreatitis. In conclusion, PET/CT was a high sensitive and EUS was a high specific modality in diagnosing patients with pancreatic cancer. PET/CT and EUS could play different roles during different conditions in diagnosing pancreatic carcinoma.

Standardizing effect size from linear regression models with log-transformed variables for meta-analysis.

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Rodríguez-Barranco, Miguel; Tobías, Aurelio; Redondo, Daniel; Molina-Portillo, Elena; Sánchez, María José

2017-03-17

Meta-analysis is very useful to summarize the effect of a treatment or a risk factor for a given disease. Often studies report results based on log-transformed variables in order to achieve the principal assumptions of a linear regression model. If this is the case for some, but not all studies, the effects need to be homogenized. We derived a set of formulae to transform absolute changes into relative ones, and vice versa, to allow including all results in a meta-analysis. We applied our procedure to all possible combinations of log-transformed independent or dependent variables. We also evaluated it in a simulation based on two variables either normally or asymmetrically distributed. In all the scenarios, and based on different change criteria, the effect size estimated by the derived set of formulae was equivalent to the real effect size. To avoid biased estimates of the effect, this procedure should be used with caution in the case of independent variables with asymmetric distributions that significantly differ from the normal distribution. We illustrate an application of this procedure by an application to a meta-analysis on the potential effects on neurodevelopment in children exposed to arsenic and manganese. The procedure proposed has been shown to be valid and capable of expressing the effect size of a linear regression model based on different change criteria in the variables. Homogenizing the results from different studies beforehand allows them to be combined in a meta-analysis, independently of whether the transformations had been performed on the dependent and/or independent variables.

Advances in meta-analysis: examples from internal medicine to neurology.

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Copetti, Massimiliano; Fontana, Andrea; Graziano, Giusi; Veneziani, Federica; Siena, Federica; Scardapane, Marco; Lucisano, Giuseppe; Pellegrini, Fabio

2014-01-01

We review the state of the art in meta-analysis and data pooling following the evolution of the statistical models employed. Starting from a classic definition of meta-analysis of published data, a set of apparent antinomies which characterized the development of the meta-analytic tools are reconciled in dichotomies where the second term represents a possible generalization of the first one. Particular attention is given to the generalized linear mixed models as an overall framework for meta-analysis. Bayesian meta-analysis is discussed as a further possibility of generalization for sensitivity analysis and the use of priors as a data augmentation approach. We provide relevant examples to underline how the need for adequate methods to solve practical issues in specific areas of research have guided the development of advanced methods in meta-analysis. We show how all the advances in meta-analysis naturally merge into the unified framework of generalized linear mixed models and reconcile apparently conflicting approaches. All these complex models can be easily implemented with the standard commercial software available. © 2013 S. Karger AG, Basel.

Comparative efficacy of inhaled corticosteroid and long-acting beta agonist combinations in preventing COPD exacerbations: a Bayesian network meta-analysis.

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Oba, Yuji; Lone, Nazir A

2014-01-01

A combination therapy with inhaled corticosteroid (ICS) and a long-acting beta agonist (LABA) is recommended in severe chronic obstructive pulmonary disease (COPD) patients experiencing frequent exacerbations. Currently, there are five ICS/LABA combination products available on the market. The purpose of this study was to systematically review the efficacy of various ICS/LABA combinations with a network meta-analysis. Several databases and manufacturer's websites were searched for relevant clinical trials. Randomized control trials, at least 12 weeks duration, comparing an ICS/LABA combination with active control or placebo were included. Moderate and severe exacerbations were chosen as the outcome assessment criteria. The primary analyses were conducted with a Bayesian Markov chain Monte Carlo method. Most of the ICS/LABA combinations reduced moderate-to-severe exacerbations as compared with placebo and LABA, but none of them reduced severe exacerbations. However, many studies excluded patients receiving long-term oxygen therapy. Moderate-dose ICS was as effective as high-dose ICS in reducing exacerbations when combined with LABA. ICS/LABA combinations had a class effect with regard to the prevention of COPD exacerbations. Moderate-dose ICS/LABA combination therapy would be sufficient for COPD patients when indicated. The efficacy of ICS/LABA combination therapy appeared modest and had no impact in reducing severe exacerbations. Further studies are needed to evaluate the efficacy of ICS/LABA combination therapy in severely affected COPD patients requiring long-term oxygen therapy.

A Global Meta-Analysis of the Value of Ecosystem Services Provided by Lakes.

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Reynaud, Arnaud; Lanzanova, Denis

2017-07-01

This study presents the first meta-analysis on the economic value of ecosystem services delivered by lakes. A worldwide data set of 699 observations drawn from 133 studies combines information reported in primary studies with geospatial data. The meta-analysis explores antagonisms and synergies between ecosystem services. This is the first meta-analysis to incorporate simultaneously external geospatial data and ecosystem service interactions. We first show that it is possible to reliably predict the value of ecosystem services provided by lakes based on their physical and geographic characteristics. Second, we demonstrate that interactions between ecosystem services appear to be significant for explaining lake ecosystem service values. Third, we provide an estimation of the average value of ecosystem services provided by lakes: between 106 and 140 USD$2010 per respondent per year for non-hedonic price studies and between 169 and 403 USD$2010 per property per year for hedonic price studies.

The universality of childhood emotional abuse: A meta-analysis of worldwide prevalence

NARCIS (Netherlands)

Stoltenborgh, M.; Bakermans-Kranenburg, M.J.; Alink, L.R.A.; van IJzendoorn, M.H.

2012-01-01

This comprehensive meta-analysis combined prevalence figures of child emotional abuse reported in 29 studies, including 46 independent samples with a total of 7,082,279 participants. The overall estimated prevalence was 3/1,000 for studies using informants and 363/1,000 for studies using self-report

Survival after radiotherapy in gastric cancer: Systematic review and meta-analysis

International Nuclear Information System (INIS)

Valentini, Vincenzo; Cellini, Francesco; Minsky, Bruce D.; Mattiucci, Gian Carlo; Balducci, Mario; D'Agostino, Giuseppe; D'Angelo, Elisa; Dinapoli, Nicola; Nicolotti, Nicola; Valentini, Chiara; La Torre, Giuseppe

2009-01-01

Background and purpose: A systematic review and meta-analysis was performed to assess the impact of radiotherapy on both 3- and 5-year survival in patients with resectable gastric cancer. Methods: Randomized Clinical Trials (RCTs) in which radiotherapy, (preoperative, postoperative and/or intraoperative), was compared with surgery alone or surgery plus chemotherapy in resectable gastric cancer were identified by searching web-based databases and supplemented by manual examination of reference lists. Meta-analysis was performed using Risk Ratios (RRs). Random or fixed effects models were used to combine data. The methodological quality was evaluated by Chalmers' score. Results: Radiotherapy had a significant impact on 5-year survival. Using an intent to treat (ITT) and a Per Protocol (PP) analysis, the overall 5-year RR was 1.26 (95% CI: 1.08-1.48; NNT = 17) and 1.31 (95% CI: 1.04-1.66; NNT = 13), respectively. Although the quality of the studies was variable, the data were consistent and no clear publication bias was found. Conclusion: This meta-analysis showed a statistically significant 5-year survival benefit with the addition of radiotherapy in patients with resectable gastric cancer. Radiotherapy remains a standard component in the treatment of resectable gastric cancer and new RCTs need to address the impact of new conformal radiotherapy technologies.

Inference for binomial probability based on dependent Bernoulli random variables with applications to meta-analysis and group level studies.

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Bakbergenuly, Ilyas; Kulinskaya, Elena; Morgenthaler, Stephan

2016-07-01

We study bias arising as a result of nonlinear transformations of random variables in random or mixed effects models and its effect on inference in group-level studies or in meta-analysis. The findings are illustrated on the example of overdispersed binomial distributions, where we demonstrate considerable biases arising from standard log-odds and arcsine transformations of the estimated probability p̂, both for single-group studies and in combining results from several groups or studies in meta-analysis. Our simulations confirm that these biases are linear in ρ, for small values of ρ, the intracluster correlation coefficient. These biases do not depend on the sample sizes or the number of studies K in a meta-analysis and result in abysmal coverage of the combined effect for large K. We also propose bias-correction for the arcsine transformation. Our simulations demonstrate that this bias-correction works well for small values of the intraclass correlation. The methods are applied to two examples of meta-analyses of prevalence. © 2016 The Authors. Biometrical Journal Published by Wiley-VCH Verlag GmbH & Co. KGaA.

Efficacy and Safety of Initial Combination Treatment of an Alpha Blocker with an Anticholinergic Medication in Benign Prostatic Hyperplasia Patients with Lower Urinary Tract Symptoms: Updated Meta-Analysis.

Directory of Open Access Journals (Sweden)

Hyun Jung Kim

Full Text Available There is still controversy as to whether initial combination treatment is superior to serial addition of anticholinergics after maintenance or induction of alpha blockers in benign prostatic hyperplasia (BPH/lower urinary tract symptoms (LUTS.The objective of this study was to determine the benefits and safety of initial combination treatment of an alpha blocker with anticholinergic medication in BPH/LUTS through a systematic review and meta-analysis.We conducted a meta-analysis of improvement in LUTS using International Prostate Symptom Score (IPSS, maximal urinary flow rate (Qmax, post-voided residual volume (PVR, and quality of life (QoL.In total, 16 studies were included in our analysis, with a total sample size of 3,548 subjects (2,195 experimental subjects and 1,353 controls. The mean change in total IPSS improvement from baseline in the combination group versus the alpha blocker monotherapy group was -0.03 (95% CI: -0.14-0.08. The pooled overall SMD change of storage IPSS improvement from baseline was -0.28 (95% CI: -0.40 - -0.17. The pooled overall SMD changes of QoL, Qmax, and PVR were -0.29 (95% CI: -0.50 - -0.07, 0.00 (95% CI: -0.08-0.08, and 0.56 (95% CI: 0.23-0.89, respectively. There was no significant difference in the number of acute urinary retention (AUR events or PVR.Initial combination treatment of an alpha blocker with anticholinergic medication is efficacious for in BPH/ LUTS with improved measures such as storage symptoms and QoL without causing significant deterioration of voiding function.

Longitudinal analysis of meta-analysis literatures in the database of ISI Web of Science.

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Zhu, Changtai; Jiang, Ting; Cao, Hao; Sun, Wenguang; Chen, Zhong; Liu, Jinming

2015-01-01

The meta-analysis is regarded as an important evidence for making scientific decision. The database of ISI Web of Science collected a great number of high quality literatures including meta-analysis literatures. However, it is significant to understand the general characteristics of meta-analysis literatures to outline the perspective of meta-analysis. In this present study, we summarized and clarified some features on these literatures in the database of ISI Web of Science. We retrieved the meta-analysis literatures in the database of ISI Web of Science including SCI-E, SSCI, A&HCI, CPCI-S, CPCI-SSH, CCR-E, and IC. The annual growth rate, literature category, language, funding, index citation, agencies and countries/territories of the meta-analysis literatures were analyzed, respectively. A total of 95,719 records, which account for 0.38% (99% CI: 0.38%-0.39%) of all literatures, were found in the database. From 1997 to 2012, the annual growth rate of meta-analysis literatures was 18.18%. The literatures involved in many categories, languages, fundings, citations, publication agencies, and countries/territories. Interestingly, the index citation frequencies of the meta-analysis were significantly higher than that of other type literatures such as multi-centre study, randomize controlled trial, cohort study, case control study, and cases report (Panalysis has been becoming more and more prominent in recent years. In future, in order to promote the validity of meta-analysis, the CONSORT and PRISMA standard should be continuously popularized in the field of evidence-based medicine.

Teaching tools in Evidence Based Practice: evaluation of reusable learning objects (RLOs for learning about Meta-analysis

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Wharrad Heather

2011-05-01

Full Text Available Abstract Background All healthcare students are taught the principles of evidence based practice on their courses. The ability to understand the procedures used in systematically reviewing evidence reported in studies, such as meta-analysis, are an important element of evidence based practice. Meta-analysis is a difficult statistical concept for healthcare students to understand yet it is an important technique used in systematic reviews to pool data from studies to look at combined effectiveness of treatments. In other areas of the healthcare curricula, by supplementing lectures, workbooks and workshops with pedagogically designed, multimedia learning objects (known as reusable learning objects or RLOs we have shown an improvement in students' perceived understanding in subjects they found difficult. In this study we describe the development and evaluation of two RLOs on meta-analysis. The RLOs supplement associated lectures and aim to improve students' understanding of meta-analysis in healthcare students. Methods Following a quality controlled design process two RLOs were developed and delivered to two cohorts of students, a Master in Public Health course and Postgraduate diploma in nursing course. Students' understanding of five key concepts of Meta-analysis were measured before and after a lecture and again after RLO use. RLOs were also evaluated for their educational value, learning support, media attributes and usability using closed and open questions. Results Students rated their understanding of meta-analysis as improved after a lecture and further improved after completing the RLOs (Wilcoxon paired test, p Conclusions Meta-analysis RLOs that are openly accessible and unrestricted by usernames and passwords provide flexible support for students who find the process of meta-analysis difficult.

Systematic Review and Meta-Analysis of Randomized Controlled Trials of Xingnaojing Treatment for Stroke

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Weijun Peng

2014-01-01

Full Text Available Objective. Xingnaojing injection (XNJ is a well-known traditional Chinese patent medicine (TCPM for stroke. The aim of this study is to assess the efficacy of XNJ for stroke including ischemic stroke, intracerebral hemorrhage (ICH, and subarachnoid hemorrhage (SAH. Methods. An extensive search was performed within using eight databases up to November 2013. Randomized controlled trials (RCTs on XNJ for treatment of stroke were collected. Study selection, data extraction, quality assessment, and meta-analysis were conducted according to the Cochrane standards, and RevMan5.0 was used for meta-analysis. Results. This review included 13 RCTs and a total of 1,514 subjects. The overall methodological quality was poor. The meta-analysis showed that XNJ combined with conventional treatment was more effective for total efficacy, neurological deficit improvement, and reduction of TNF-α levels compared with those of conventional treatment alone. Three trials reported adverse events, of these one trial reported mild impairment of kidney and liver function, whereas the other two studies failed to report specific adverse events. Conclusion. Despite the limitations of this review, we suggest that XNJ in combination with conventional medicines might be beneficial for the treatment of stroke. Currently there are various methodological problems in the studies. Therefore, high-quality, large-scale RCTs are urgently needed.

Multivariate meta-analysis: Potential and promise

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Jackson, Dan; Riley, Richard; White, Ian R

2011-01-01

The multivariate random effects model is a generalization of the standard univariate model. Multivariate meta-analysis is becoming more commonly used and the techniques and related computer software, although continually under development, are now in place. In order to raise awareness of the multivariate methods, and discuss their advantages and disadvantages, we organized a one day ‘Multivariate meta-analysis’ event at the Royal Statistical Society. In addition to disseminating the most recent developments, we also received an abundance of comments, concerns, insights, critiques and encouragement. This article provides a balanced account of the day's discourse. By giving others the opportunity to respond to our assessment, we hope to ensure that the various view points and opinions are aired before multivariate meta-analysis simply becomes another widely used de facto method without any proper consideration of it by the medical statistics community. We describe the areas of application that multivariate meta-analysis has found, the methods available, the difficulties typically encountered and the arguments for and against the multivariate methods, using four representative but contrasting examples. We conclude that the multivariate methods can be useful, and in particular can provide estimates with better statistical properties, but also that these benefits come at the price of making more assumptions which do not result in better inference in every case. Although there is evidence that multivariate meta-analysis has considerable potential, it must be even more carefully applied than its univariate counterpart in practice. Copyright © 2011 John Wiley & Sons, Ltd. PMID:21268052

Incidence of HIV-associated tuberculosis among individuals taking combination antiretroviral therapy: a systematic review and meta-analysis.

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Tendesayi Kufa

Full Text Available Knowledge of tuberculosis incidence and associated factors is required for the development and evaluation of strategies to reduce the burden of HIV-associated tuberculosis.Systematic literature review and meta-analysis of tuberculosis incidence rates among HIV-infected individuals taking combination antiretroviral therapy.From PubMed, EMBASE and Global Index Medicus databases, 42 papers describing 43 cohorts (32 from high/intermediate and 11 from low tuberculosis burden settings were included in the qualitative review and 33 in the quantitative review. Cohorts from high/intermediate burden settings were smaller in size, had lower median CD4 cell counts at study entry and fewer person-years of follow up. Tuberculosis incidence rates were higher in studies from Sub-Saharan Africa and from World Bank low/middle income countries. Tuberculosis incidence rates decreased with increasing CD4 count at study entry and duration on combination antiretroviral therapy. Summary estimates of tuberculosis incidence among individuals on combination antiretroviral therapy were higher for cohorts from high/intermediate burden settings compared to those from the low tuberculosis burden settings (4.17 per 100 person-years [95% Confidence Interval (CI 3.39-5.14 per 100 person-years] vs. 0.4 per 100 person-years [95% CI 0.23-0.69 per 100 person-years] with significant heterogeneity observed between the studies.Tuberculosis incidence rates were high among individuals on combination antiretroviral therapy in high/intermediate burden settings. Interventions to prevent tuberculosis in this population should address geographical, socioeconomic and individual factors such as low CD4 counts and prior history of tuberculosis.

MicroRNA meta-signature of oral cancer: evidence from a meta-analysis.

Science.gov (United States)

Zeljic, Katarina; Jovanovic, Ivan; Jovanovic, Jasmina; Magic, Zvonko; Stankovic, Aleksandra; Supic, Gordana

2018-03-01

It was the aim of the study to identify commonly deregulated miRNAs in oral cancer patients by performing a meta-analysis of previously published miRNA expression profiles in cancer and matched normal non-cancerous tissue in such patients. Meta-analysis included seven independent studies analyzed by a vote-counting method followed by bioinformatic enrichment analysis. Amongst seven independent studies included in the meta-analysis, 20 miRNAs were found to be deregulated in oral cancer when compared with non-cancerous tissue. Eleven miRNAs were consistently up-regulated in three or more studies (miR-21-5p, miR-31-5p, miR-135b-5p, miR-31-3p, miR-93-5p, miR-34b-5p, miR-424-5p, miR-18a-5p, miR-455-3p, miR-450a-5p, miR-21-3p), and nine were down-regulated (miR-139-5p, miR-30a-3p, miR-376c-3p, miR-885-5p, miR-375, miR-486-5p, miR-411-5p, miR-133a-3p, miR-30a-5p). The meta-signature of identified miRNAs was functionally characterized by KEGG enrichment analysis. Twenty-four KEGG pathways were significantly enriched, and TGF-beta signaling was the most enriched signaling pathway. The highest number of meta-signature miRNAs was involved in the sphingolipid signaling pathway. Natural killer cell-mediated cytotoxicity was the pathway with most genes regulated by identified miRNAs. The rest of the enriched pathways in our miRNA list describe different malignancies and signaling. The identified miRNA meta-signature might be considered as a potential battery of biomarkers when distinguishing oral cancer tissue from normal, non-cancerous tissue. Further mechanistic studies are warranted in order to confirm and fully elucidate the role of deregulated miRNAs in oral cancer.

Meta-analysis in microbiology

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N Pabalan

2014-01-01

Full Text Available The use of meta-analysis in microbiology may facilitate decision-making that impacts public health policy. Directed at clinicians and researchers in microbiology, this review outlines the steps in performing this statistical technique, addresses its biases and describes its value in this discipline. The survey to estimate extent of the use of meta-analyses in microbiology shows the remarkable growth in the use of this research methodology, from a minimal Asian output to a level comparable with those of Europe and North America in the last 7 years.

Determinants of investment behaviour. Methods and applications of meta-analysis

International Nuclear Information System (INIS)

Koetse, M.J.

2006-01-01

Meta-analysis is gradually gaining ground in economics as a research method to objectively and quantitatively summarise a body of existing empirical evidence. This dissertation studies the performance of well-known meta-analytic models and presents two meta-analysis applications. Despite its many attractive features, meta-analysis faces several methodical difficulties, especially when applied in economic research. We investigate two specific methodical problems that any meta-analysis in economics will have to deal with, viz., systematic effect-size variation due to primary-study misspecifications, and random effect-size heterogeneity. Using Monte-Carlo analysis we investigate the effects of these methodical problems on the results of a meta-analysis, and study the small-sample properties of several well-known and often applied meta-estimators. The focus of the meta-analysis applications is on two topics that are relevant for understanding investment behaviour, viz., the impact of uncertainty on investment spending, and the potential for substitution of capital for energy in production processes. In the first application we aim to shed light on the direction of the relationship between investment and uncertainty, and to uncover which factors are empirically relevant for explaining the wide variety in study outcomes. In the second application our goal is to analyse the direction and magnitude of capital-energy substitution potential, and to analyse the empirical relevance of suggested sources of variation in elasticity estimates

Determinants of investment behaviour. Methods and applications of meta-analysis

Energy Technology Data Exchange (ETDEWEB)

Koetse, M.J.

2006-03-14

Meta-analysis is gradually gaining ground in economics as a research method to objectively and quantitatively summarise a body of existing empirical evidence. This dissertation studies the performance of well-known meta-analytic models and presents two meta-analysis applications. Despite its many attractive features, meta-analysis faces several methodical difficulties, especially when applied in economic research. We investigate two specific methodical problems that any meta-analysis in economics will have to deal with, viz., systematic effect-size variation due to primary-study misspecifications, and random effect-size heterogeneity. Using Monte-Carlo analysis we investigate the effects of these methodical problems on the results of a meta-analysis, and study the small-sample properties of several well-known and often applied meta-estimators. The focus of the meta-analysis applications is on two topics that are relevant for understanding investment behaviour, viz., the impact of uncertainty on investment spending, and the potential for substitution of capital for energy in production processes. In the first application we aim to shed light on the direction of the relationship between investment and uncertainty, and to uncover which factors are empirically relevant for explaining the wide variety in study outcomes. In the second application our goal is to analyse the direction and magnitude of capital-energy substitution potential, and to analyse the empirical relevance of suggested sources of variation in elasticity estimates.

Meta-analysis: low-dose intake of vitamin E combined with other vitamins or minerals may decrease all-cause mortality.

Science.gov (United States)

Jiang, Shan; Pan, Zhenyu; Li, Hui; Li, Fenglan; Song, Yanyan; Qiu, Yu

2014-01-01

It has been suggested that vitamin E alone or combined with other vitamins or minerals can prevent oxidative stress and slow oxidative injury-related diseases, such as cardiovascular disease and cancer. A comprehensive search of PubMed/MEDLINE, EMBASE and the Cochrane Library was performed. Relative risk was used as an effect measure to compare the intervention and control groups. A total of 33 trials were included in the meta-analysis. Neither vitamin E intake alone (RR=1.01; 95% CI, 0.97 to 1.04; p=0.77) nor vitamin E intake combined with other agents (RR=0.97; 95% CI, 0.89 to 1.06; p=0.55) was correlated with all-cause mortality. Subgroup analyses revealed that low-dose vitamin E supplementation combined with other agents is associated with a statistically significant reduction in all-cause mortality (RR=0.92; 95% CI, 0.86 to 0.98; p=0.01), and vitamin E intake combined with other agents is associated with a statistically significant reduction in mortality rates among individuals without probable or confirmed diseases (RR=0.92; 95% CI, 0.86 to 0.99; p=0.02). Neither vitamin E intake alone nor combined with other agents is associated with a reduction in all-cause mortality. But a low dose (vitamin E combined with other agents is correlated with a reduction in all-cause mortality, and vitamin E intake combined with other agents is correlated with a reduction in the mortality rate among individuals without probable or confirmed diseases.

Meta-analysis: Association of Helicobacter pylori infection with Parkinson's diseases.

Science.gov (United States)

Shen, Xiaoli; Yang, Huazhen; Wu, Yili; Zhang, Dongfeng; Jiang, Hong

2017-10-01

The results from observational studies on the relationship between helicobacter pylori (H. pylori) infection and Parkinson's disease remain controversial. A meta-analysis was conducted to evaluate the association between helicobacter pylori infection and Parkinson's disease. A comprehensive literature search was performed on relevant studies published from January 1983 to January 2017 in PubMed, Web of Science and EMBASE databases. The fixed or random effects model was used to pool the odds ratio with 95% confidence interval from individual studies. Publication bias was estimated by Egger's test and the funnel plot. Eight eligible studies involving 33 125 participants were included in this meta-analysis. Compared with the no helicobacter pylori infected person, the pooled odds ratio of Parkinson's disease in helicobacter pylori infected person was 1.59 (95% confidence interval: 1.37-1.85). In subgroup analyzes, the combined odds ratios were 1.96 (1.23-3.12) in Asia, 1.55 (1.32-1.82) in Europe, 1.59 (1.35-1.88) in case-control studies, 1.56 (1.01-2.39) in cross-sectional studies, 1.56 (1.32-1.85) in studies with confounders adjusted, and 1.71 (1.21-2.43) in studies with no confounder adjusted, respectively. This meta-analysis indicated that H. pylori infection might be associated with the risk of Parkinson's disease. © 2017 John Wiley & Sons Ltd.

Meta-analysis of individual registry results enhances international registry collaboration.

Science.gov (United States)

Paxton, Elizabeth W; Mohaddes, Maziar; Laaksonen, Inari; Lorimer, Michelle; Graves, Stephen E; Malchau, Henrik; Namba, Robert S; Kärrholm, John; Rolfson, Ola; Cafri, Guy

2018-03-28

Background and purpose - Although common in medical research, meta-analysis has not been widely adopted in registry collaborations. A meta-analytic approach in which each registry conducts a standardized analysis on its own data followed by a meta-analysis to calculate a weighted average of the estimates allows collaboration without sharing patient-level data. The value of meta-analysis as an alternative to individual patient data analysis is illustrated in this study by comparing the risk of revision of porous tantalum cups versus other uncemented cups in primary total hip arthroplasties from Sweden, Australia, and a US registry (2003-2015). Patients and methods - For both individual patient data analysis and meta-analysis approaches a Cox proportional hazard model was fit for time to revision, comparing porous tantalum (n = 23,201) with other uncemented cups (n = 128,321). Covariates included age, sex, diagnosis, head size, and stem fixation. In the meta-analysis approach, treatment effect size (i.e., Cox model hazard ratio) was calculated within each registry and a weighted average for the individual registries' estimates was calculated. Results - Patient-level data analysis and meta-analytic approaches yielded the same results with the porous tantalum cups having a higher risk of revision than other uncemented cups (HR (95% CI) 1.6 (1.4-1.7) and HR (95% CI) 1.5 (1.4-1.7), respectively). Adding the US cohort to the meta-analysis led to greater generalizability, increased precision of the treatment effect, and similar findings (HR (95% CI) 1.6 (1.4-1.7)) with increased risk of porous tantalum cups. Interpretation - The meta-analytic technique is a viable option to address privacy, security, and data ownership concerns allowing more expansive registry collaboration, greater generalizability, and increased precision of treatment effects.

Drivers of Wetland Conversion: a Global Meta-Analysis

NARCIS (Netherlands)

van Asselen, S.; Verburg, P.H.; Vermaat, J.E.; Janse, J.

2013-01-01

Meta-analysis of case studies has become an important tool for synthesizing case study findings in land change. Meta-analyses of deforestation, urbanization, desertification and change in shifting cultivation systems have been published. This present study adds to this literature, with an analysis

Methotrexate for the Treatment of Pediatric Crohn's Disease: A Systematic Review and Meta-analysis.

Science.gov (United States)

Colman, Ruben J; Lawton, Rachel C; Dubinsky, Marla C; Rubin, David T

2018-04-23

Methotrexate (MTX) is an immunomodulator used for the treatment of pediatric inflammatory bowel disease (IBD). There are currently no RCTs that assess the treatment efficacy of methotrexate within the pediatric IBD patient population. This systematic review and meta-analysis assesses the efficacy of MTX therapy among the existing pediatric literature. A systematic literature search was performed using MEDLINE and the Cochrane library from inception until March 2016. Synonyms for 'pediatric', 'methotrexate' and 'IBD' were utilized as both free text and MESH search terms. The studies included contained clinical remission (CR) rates for MTX treatment of pediatric IBD patients 18 yrs old, as mono- or combination therapy. Case studies with <10 patients were excluded. Quality assessment was performed with the Newcastle-Ottawa Scale. Meta-analysis calculated pooled CR rates. A random-effects meta-analysis with forest plots was performed using R. Fourteen (11 monotherapy, 1 combination therapy, 2 both; n = 886 patients) observational studies were eligible out of 202 studies. No interventional studies were identified. The pooled achieved CR rate for pediatric CD patients on monotherapy within 3-6 months was 57.7% (95% CI 48.2-66.6%), (P =0.22; I2 = 29.8%). The CR was 37.1% (95% CI 29.5-45.5%), (P = 0.20; I2 = 37.4%) for maintenance therapy at 12 months. Sub-analysis could not identify CR differences between MTX administration types, thiopurine exposure. This meta-analysis demonstrated that, over 50% of pediatric Crohn's disease patients induced with methotrexate achieved clinical remission, while 12-month remission rate was only 37%. Prospective controlled interventional trials should assess treatment efficacy among patient subgroups. 10.1093/ibd/izy078_video1izy078.video15774883936001.

Meta-Analysis for Primary and Secondary Data Analysis: The Super-Experiment Metaphor.

Science.gov (United States)

Jackson, Sally

1991-01-01

Considers the relation between meta-analysis statistics and analysis of variance statistics. Discusses advantages and disadvantages as a primary data analysis tool. Argues that the two approaches are partial paraphrases of one another. Advocates an integrative approach that introduces the best of meta-analytic thinking into primary analysis…

Visualizing the flow of evidence in network meta-analysis and characterizing mixed treatment comparisons.

Science.gov (United States)

König, Jochem; Krahn, Ulrike; Binder, Harald

2013-12-30

Network meta-analysis techniques allow for pooling evidence from different studies with only partially overlapping designs for getting a broader basis for decision support. The results are network-based effect estimates that take indirect evidence into account for all pairs of treatments. The results critically depend on homogeneity and consistency assumptions, which are sometimes difficult to investigate. To support such evaluation, we propose a display of the flow of evidence and introduce new measures that characterize the structure of a mixed treatment comparison. Specifically, a linear fixed effects model for network meta-analysis is considered, where the network estimates for two treatments are linear combinations of direct effect estimates comparing these or other treatments. The linear coefficients can be seen as the generalization of weights known from classical meta-analysis. We summarize properties of these coefficients and display them as a weighted directed acyclic graph, representing the flow of evidence. Furthermore, measures are introduced that quantify the direct evidence proportion, the mean path length, and the minimal parallelism of mixed treatment comparisons. The graphical display and the measures are illustrated for two published network meta-analyses. In these applications, the proposed methods are seen to render transparent the process of data pooling in mixed treatment comparisons. They can be expected to be more generally useful for guiding and facilitating the validity assessment in network meta-analysis. Copyright © 2013 John Wiley & Sons, Ltd.

Effects of Combination Therapy With Immunomodulators on Trough Levels and Antibodies Against Tumor Necrosis Factor Antagonists in Patients With Inflammatory Bowel Disease: A Meta-analysis.

Science.gov (United States)

Qiu, Yun; Mao, Ren; Chen, Bai-Li; Zhang, Sheng-Hong; Guo, Jing; He, Yao; Zeng, Zhi-Rong; Ben-Horin, Shomron; Chen, Min-Hu

2017-09-01

It is not clear whether combination therapy with immunomodulators affects the immunogenicity of tumor necrosis factor (TNF) antagonists in patients with inflammatory bowel disease. We performed a meta-analysis to quantify the effects of combined immunomodulator therapy on the presence of antibodies against TNF antagonists (antidrug antibodies [ADAs]) and trough levels of anti-TNF agents. We systematically searched publication databases for studies that reported prevalence of ADAs in patients who received anti-TNF agents. Raw data from studies that met the inclusion criteria were pooled to determine effect estimates. We performed subgroup and metaregression analyses to determine the level of heterogeneity among study outcomes. We analyzed findings from 35 studies that met inclusion criteria (results reported from 6790 patients with inflammatory bowel disease). The pooled risk ratio for formation of ADAs in patients receiving combined therapy with immunomodulators, versus that of patients receiving anti-TNF monotherapy, was 0.49 (95% confidence interval, 0.41-0.59; P immunomodulators (standardized mean difference, 0.11; 95% confidence interval, 0.19-0.41; P = .47). Subgroup analyses of patients treated with different TNF antagonists revealed no difference in the formation of ADAs (P = .50 for interaction); the protective effect of immunomodulators did not differ with type of drug patients were given (methotrexate vs thiopurines), or assay for ADA. We observed heterogeneity only among studies of patients with ulcerative colitis (I 2  = 76%). Funnel plot and Egger test analyses indicated publication bias in the studies (P = .001). In a meta-analysis of published studies, we associated combined treatment with immunomodulators with reduced risk of formation of antibodies against TNF antagonists in patients with inflammatory bowel disease. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

Long working hours and depressive symptoms: systematic review and meta-analysis of published studies and unpublished individual participant data

OpenAIRE

Virtanen, M.; Jokela, M.; Madsen, I. E.; Magnusson Hanson, L. L.; Lallukka, T.; Nyberg, S. T.; Alfredsson, L.; Batty, D.; Bjorner, J. B.; Borritz, M.; Burr, H.; Dragano, N.; Erbel, R.; Ferrie, J. E.; Heikkilä, K.

2018-01-01

Objectives This systematic review and meta-analysis combined published study-level data and unpublished individual-participant data with the aim of quantifying the relation between long working hours and the onset of depressive symptoms. Methods We searched PubMed and Embase for published prospective cohort studies and included available cohorts with unpublished individual-participant data. We used a random-effects meta-analysis to calculate summary estimates across studies. Results We identi...

The Effect of Educational Leadership on Students' Achievement: A Meta-Analysis Study

Science.gov (United States)

Karadag, Engin; Bektas, Fatih; Çogaltay, Nazim; Yalçin, Mikail

2015-01-01

In this meta-analysis study, different leadership styles were combined, and the relationship between educational leadership and student achievement was analyzed. In the literature review, 57 research articles/dissertations, independent from one another, were brought together, and 28,964 study subjects were included in the sample group. The results…

Rapid Onset of the Effects of Combined Selective Serotonin Reuptake Inhibitors and Electroacupuncture on Primary Depression: A Meta-Analysis.

Science.gov (United States)

Zhang, Yue; Qu, Shan-shan; Zhang, Ji-ping; Sun, Ya-ling; Liu, Wei-lu; Xie, Ling; Huang, Yong; Chen, Jun-qi

2016-01-01

To evaluate the efficacy and safety of combined selective serotonin reuptake inhibitors (SSRIs) and electroacupuncture therapies for the early treatment of primary depression. Randomized controlled trials (RCTs) were analyzed to compare therapy combining SSRIs and electroacupuncture to SSRI therapy alone. The RCTs were identified by searching, among others, PubMed, the Cochrane Library, the Chinese National Knowledge Infrastructure, the Chongqing VIP database for Chinese Technical Periodicals, WANFANG DATA, and the Chinese Biological Medical Literature Database. Scores from Self-Rated Depression Scale (SDS), the Hamilton Depression Scale (HAMD), the Side Effect Rating Scale (SERS), and the Treatment Emergent Symptom Scale (TESS) were analyzed and coded by two independent investigators and used to evaluate the safety and efficacy of treatment. Statistical analyses were performed using RevMan 5.2 software. Six RCTs were analyzed. The meta-analysis revealed that the combined therapy of SSRIs and electroacupuncture were associated with superior scores on the HAMD, SDS, and SERS measures compared with SSRIs alone after 1-4 weeks of treatment: HAMD scores, mean difference (MD)(1 week), 2.32 (95% confidence interval [CI](1 week), 1.47-3.16, p(1 week)electroacupuncture therapies is more efficient than treatments with SSRIs alone and leads to a better and earlier control of depressive symptoms.

metaCCA: summary statistics-based multivariate meta-analysis of genome-wide association studies using canonical correlation analysis.

Science.gov (United States)

Cichonska, Anna; Rousu, Juho; Marttinen, Pekka; Kangas, Antti J; Soininen, Pasi; Lehtimäki, Terho; Raitakari, Olli T; Järvelin, Marjo-Riitta; Salomaa, Veikko; Ala-Korpela, Mika; Ripatti, Samuli; Pirinen, Matti

2016-07-01

A dominant approach to genetic association studies is to perform univariate tests between genotype-phenotype pairs. However, analyzing related traits together increases statistical power, and certain complex associations become detectable only when several variants are tested jointly. Currently, modest sample sizes of individual cohorts, and restricted availability of individual-level genotype-phenotype data across the cohorts limit conducting multivariate tests. We introduce metaCCA, a computational framework for summary statistics-based analysis of a single or multiple studies that allows multivariate representation of both genotype and phenotype. It extends the statistical technique of canonical correlation analysis to the setting where original individual-level records are not available, and employs a covariance shrinkage algorithm to achieve robustness.Multivariate meta-analysis of two Finnish studies of nuclear magnetic resonance metabolomics by metaCCA, using standard univariate output from the program SNPTEST, shows an excellent agreement with the pooled individual-level analysis of original data. Motivated by strong multivariate signals in the lipid genes tested, we envision that multivariate association testing using metaCCA has a great potential to provide novel insights from already published summary statistics from high-throughput phenotyping technologies. Code is available at https://github.com/aalto-ics-kepaco anna.cichonska@helsinki.fi or matti.pirinen@helsinki.fi Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press.

Autologous Transplantation for Newly Diagnosed Multiple Myeloma in the Era of Novel Agent Induction: A Systematic Review and Meta-analysis.

Science.gov (United States)

Dhakal, Binod; Szabo, Aniko; Chhabra, Saurabh; Hamadani, Mehdi; D'Souza, Anita; Usmani, Saad Z; Sieracki, Rita; Gyawali, Bishal; Jackson, Jeffrey L; Asimakopoulos, Fotis; Hari, Parameswaran N

2018-03-01

The role of high-dose therapy with melphalan followed by autologous stem cell transplant (HDT/ASCT) in patients with multiple myeloma continues to be debated in the context of novel agent induction. To perform a systematic review, conventional meta-analysis, and network meta-analysis of all phase 3 randomized clinical trials (RCTs) evaluating the role of HDT/ASCT. We performed a systematic literature search of Cochrane Central, MEDLINE, and Scopus from January 2000 through April 2017 and relevant annual meeting abstracts from January 2014 to December 2016. The following search terms were used: "myeloma" combined with "autologous," "transplant," "myeloablative," or "stem cell." Phase 3 RCTs comparing HDT/ASCT with standard-dose therapy (SDT) using novel agents were assessed. Studies comparing single HDT/ASCT with bortezomib, lenalidomide, and dexamethasone consolidation and tandem transplantation were included for network meta-analysis. For the random effects meta-analysis, we used hazard ratios (HRs) and corresponding 95% CIs. The primary outcome was progression-free survival (PFS). Overall survival (OS), complete response, and treatment-related mortality were secondary outcomes. A total of 4 RCTs (2421 patients) for conventional meta-analysis and 5 RCTs (3171 patients) for network meta-analysis were selected. The combined odds for complete response were 1.27 (95% CI, 0.97-1.65; P = .07) with HDT/ASCT when compared with SDT. The combined HR for PFS was 0.55 (95% CI, 0.41-0.74; P Meta-regression showed that longer follow-up was associated with superior PFS (HR/mo, 0.98; 95% CI, 0.96-0.99; P = .03) and OS (HR/mo, 0.90; 95% CI, 0.84-0.96; P = .002). For PFS, tandem HDT/ASCT had the most favorable HR (0.49; 95% CI, 0.37-0.65) followed by single HDT/ASCT with bortezomib, lenalidomide, and dexamethasone (HR, 0.53; 95% CI, 0.37-0.76) and single HDT/ASCT alone (HR, 0.68; 95% CI, 0.53-0.87) compared with SDT. For OS, none of the HDT/ASCT-based approaches had a

The Economic Value of Mangroves: A Meta-Analysis

Science.gov (United States)

Marwa Salem; D. Evan Mercer

2012-01-01

This paper presents a synthesis of the mangrove ecosystem valuation literature through a meta-regression analysis. The main contribution of this study is that it is the first meta-analysis focusing solely on mangrove forests, whereas previous studies have included different types of wetlands. The number of studies included in the regression analysis is 44 for a total...

Genome-wide association study and meta-analysis find that over 40 loci affect risk of type 1 diabetes

DEFF Research Database (Denmark)

Barrett, Jeffrey C; Clayton, David G; Concannon, Patrick

2009-01-01

Type 1 diabetes (T1D) is a common autoimmune disorder that arises from the action of multiple genetic and environmental risk factors. We report the findings of a genome-wide association study of T1D, combined in a meta-analysis with two previously published studies. The total sample set included 7......,514 cases and 9,045 reference samples. Forty-one distinct genomic locations provided evidence for association with T1D in the meta-analysis (P

The clinical role of microRNA-21 as a promising biomarker in the diagnosis and prognosis of colorectal cancer: a systematic review and meta-analysis.

Science.gov (United States)

Peng, Qiliang; Zhang, Xueli; Min, Ming; Zou, Li; Shen, Peipei; Zhu, Yaqun

2017-07-04

This systematic analysis aimed to investigate the value of microRNA-21 (miR-21) in colorectal cancer for multiple purposes, including diagnosis and prognosis, as well as its predictive power in combination biomarkers. Fifty-seven eligible studies were included in our meta-analysis, including 25 studies for diagnostic meta-analysis and 32 for prognostic meta-analysis. For the diagnostic meta-analysis of miR-21 alone, the overall pooled results for sensitivity, specificity, and area under the curve (AUC) were 0.64 (95% CI: 0.53-0.74), 0.85 (0.79-0.90), and 0.85 (0.81-0.87), respectively. Circulating samples presented corresponding values of 0.72 (0.63-0.79), 0.84 (0.78-0.89), and 0.86 (0.83-0.89), respectively. For the diagnostic meta-analysis of miR-21-related combination biomarkers, the above three parameters were 0.79 (0.69-0.86), 0.79 (0.68-0.87), and 0.86 (0.83-0.89), respectively. Notably, subgroup analysis suggested that miRNA combination markers in circulation exhibited high predictive power, with sensitivity of 0.85 (0.70-0.93), specificity of 0.86 (0.77-0.92), and AUC of 0.92 (0.89-0.94). For the prognostic meta-analysis, patients with higher expression of miR-21 had significant shorter disease-free survival [DFS; pooled hazard ratio (HR): 1.60; 95% CI: 1.20-2.15] and overall survival (OS; 1.54; 1.27-1.86). The combined HR in tissues for DFS and OS were 1.76 (1.31-2.36) and 1.58 (1.30-1.93), respectively. Our comprehensive systematic review revealed that circulating miR-21 may be suitable as a diagnostic biomarker, while tissue miR-21 could be a prognostic marker for colorectal cancer. In addition, miRNA combination biomarkers may provide a new approach for clinical application.

The interventional effect of new drugs combined with the Stupp protocol on glioblastoma: A network meta-analysis.

Science.gov (United States)

Li, Mei; Song, Xiangqi; Zhu, Jun; Fu, Aijun; Li, Jianmin; Chen, Tong

2017-08-01

New therapeutic agents in combination with the standard Stupp protocol (a protocol about the temozolomide combined with radiotherapy treatment with glioblastoma was research by Stupp R in 2005) were assessed to evaluate whether they were superior to the Stupp protocol alone, to determine the optimum treatment regimen for patients with newly diagnosed glioblastoma. We implemented a search strategy to identify studies in the following databases: PubMed, Cochrane Library, EMBASE, CNKI, CBM, Wanfang, and VIP, and assessed the quality of extracted data from the trials included. Statistical software was used to perform network meta-analysis. The use of novel therapeutic agents in combination with the Stupp protocol were all shown to be superior than the Stupp protocol alone for the treatment of newly diagnosed glioblastoma, ranked as follows: cilengitide 2000mg/5/week, bevacizumab in combination with irinotecan, nimotuzumab, bevacizumab, cilengitide 2000mg/2/week, cytokine-induced killer cell immunotherapy, and the Stupp protocol. In terms of serious adverse effects, the intervention group showed a 29% increase in the incidence of adverse events compared with the control group (patients treated only with Stupp protocol) with a statistically significant difference (RR=1.29; 95%CI 1.17-1.43; P<0.001). The most common adverse events were thrombocytopenia, lymphopenia, neutropenia, pneumonia, nausea, and vomiting, none of which were significantly different between the groups except for neutropenia, pneumonia, and embolism. All intervention drugs evaluated in our study were superior to the Stupp protocol alone when used in combination with it. However, we could not conclusively confirm whether cilengitide 2000mg/5/week was the optimum regime, as only one trial using this protocol was included in our study. Copyright © 2017. Published by Elsevier B.V.

Family-Based Interventions in Preventing Children and Adolescents from Using Tobacco: A Systematic Review and Meta-Analysis.

Science.gov (United States)

Thomas, Roger E; Baker, Philip R A; Thomas, Bennett C

2016-07-01

Tobacco is the main preventable cause of death and disease worldwide. Adolescent smoking is increasing in many countries with poorer countries following the earlier experiences of affluent countries. Preventing adolescents from starting smoking is crucial to decreasing tobacco-related illness. To assess effectiveness of family-based interventions alone and combined with school-based interventions to prevent children and adolescents from initiating tobacco use. Fourteen bibliographic databases and the Internet, journals hand-searched, and experts consulted. Randomized controlled trials (RCTs) with children or adolescents and families, interventions to prevent starting tobacco use, and follow-up ≥6 months. Abstracts/titles independently assessed and data independently entered by 2 authors. Risk of bias was assessed with the Cochrane Risk-of-Bias tool. Twenty-seven RCTs were included. Nine trials of never-smokers compared with a control provided data for meta-analysis. Family intervention trials had significantly fewer students who started smoking. Meta-analysis of 2 RCTs of combined family and school interventions compared with school only, showed additional significant benefit. The common feature of effective high-intensity interventions was encouraging authoritative parenting. Only 14 RCTs provided data for meta-analysis (approximately a third of participants). Of the 13 RCTs that did not provide data for meta-analysis 8 compared a family intervention with no intervention and 1 reported significant effects, and 5 compared a family combined with school intervention with a school intervention only and none reported additional significant effects. There is moderate-quality evidence that family-based interventions prevent children and adolescents from starting to smoke. Copyright © 2016 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.

Prognostic association of depression following myocardial infarction with mortality and cardiovascular events : A meta-analysis

NARCIS (Netherlands)

van Melle, JP; de Jonge, P; Spijkerman, TA; Tijssen, JGP; Ormel, J; van Veldhuisen, DJ; van den Brink, RHS; van den Berg, MP

2004-01-01

Objective: To assess the association of depression following myocardial infarction (MI) and cardiovascular prognosis. Methods: The authors performed a meta-analysis of references derived from MEDLINE, EMBASE, and PSYCINFO (1975-2003) combined with crossreferencing without language restrictions. The

[Development of an Excel spreadsheet for meta-analysis of indirect and mixed treatment comparisons].

Science.gov (United States)

Tobías, Aurelio; Catalá-López, Ferrán; Roqué, Marta

2014-01-01

Meta-analyses in clinical research usually aimed to evaluate treatment efficacy and safety in direct comparison with a unique comparator. Indirect comparisons, using the Bucher's method, can summarize primary data when information from direct comparisons is limited or nonexistent. Mixed comparisons allow combining estimates from direct and indirect comparisons, increasing statistical power. There is a need for simple applications for meta-analysis of indirect and mixed comparisons. These can easily be conducted using a Microsoft Office Excel spreadsheet. We developed a spreadsheet for indirect and mixed effects comparisons of friendly use for clinical researchers interested in systematic reviews, but non-familiarized with the use of more advanced statistical packages. The use of the proposed Excel spreadsheet for indirect and mixed comparisons can be of great use in clinical epidemiology to extend the knowledge provided by traditional meta-analysis when evidence from direct comparisons is limited or nonexistent.

Effectiveness of urine fibronectin as a non-invasive diagnostic biomarker in bladder cancer patients: a systematic review and meta-analysis.

Science.gov (United States)

Dong, Fan; Shen, Yifan; Xu, Tianyuan; Wang, Xianjin; Gao, Fengbin; Zhong, Shan; Chen, Shanwen; Shen, Zhoujun

2018-03-21

Previous researches pointed out that the measurement of urine fibronectin (Fn) could be a potential diagnostic test for bladder cancer (BCa). We conducted this meta-analysis to fully assess the diagnostic value of urine Fn for BCa detection. A systematic literature search in PubMed, ISI Web of Science, EMBASE, Cochrane library, and CBM was carried out to identify eligible studies evaluating the urine Fn in diagnosing BCa. Pooled sensitivity, specificity, and diagnostic odds ratio (DOR) with their 95% confidence intervals (CIs) were calculated, and summary receiver operating characteristic (SROC) curves were established. We applied the STATA 13.0, Meta-Disc 1.4, and RevMan 5.3 software to the meta-analysis. Eight separate studies with 744 bladder cancer patients were enrolled in this meta-analysis. The pooled sensitivity, specificity, and DOR were 0.80 (95%CI = 0.77-0.83), 0.79 (95%CI = 0.73-0.84), and 15.18 (95%CI = 10.07-22.87), respectively, and the area under the curve (AUC) of SROC was 0.83 (95%CI = 0.79-0.86). The diagnostic power of a combined method (urine Fn combined with urine cytology) was also evaluated, and its sensitivity and AUC were significantly higher (0.86 (95%CI = 0.82-0.90) and 0.89 (95%CI = 0.86-0.92), respectively). Meta-regression along with subgroup analysis based on various covariates revealed the potential sources of the heterogeneity and the detailed diagnostic value of each subgroup. Sensitivity analysis supported that the result was robust. No threshold effect and publication bias were found in this meta-analysis. Urine Fn may become a promising non-invasive biomarker for bladder cancer with a relatively satisfactory diagnostic power. And the combination of urine Fn with cytology could be an alternative option for detecting BCa in clinical practice. The potential value of urine Fn still needs to be validated in large, multi-center, and prospective studies.

Methodology Series Module 6: Systematic Reviews and Meta-analysis.

Science.gov (United States)

Setia, Maninder Singh

2016-01-01

Systematic reviews and meta-analysis have become an important of biomedical literature, and they provide the "highest level of evidence" for various clinical questions. There are a lot of studies - sometimes with contradictory conclusions - on a particular topic in literature. Hence, as a clinician, which results will you believe? What will you tell your patient? Which drug is better? A systematic review or a meta-analysis may help us answer these questions. In addition, it may also help us understand the quality of the articles in literature or the type of studies that have been conducted and published (example, randomized trials or observational studies). The first step it to identify a research question for systematic review or meta-analysis. The next step is to identify the articles that will be included in the study. This will be done by searching various databases; it is important that the researcher should search for articles in more than one database. It will also be useful to form a group of researchers and statisticians that have expertise in conducting systematic reviews and meta-analysis before initiating them. We strongly encourage the readers to register their proposed review/meta-analysis with PROSPERO. Finally, these studies should be reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis checklist.

The Covariance Adjustment Approaches for Combining Incomparable Cox Regressions Caused by Unbalanced Covariates Adjustment: A Multivariate Meta-Analysis Study

Directory of Open Access Journals (Sweden)

Tania Dehesh

2015-01-01

Full Text Available Background. Univariate meta-analysis (UM procedure, as a technique that provides a single overall result, has become increasingly popular. Neglecting the existence of other concomitant covariates in the models leads to loss of treatment efficiency. Our aim was proposing four new approximation approaches for the covariance matrix of the coefficients, which is not readily available for the multivariate generalized least square (MGLS method as a multivariate meta-analysis approach. Methods. We evaluated the efficiency of four new approaches including zero correlation (ZC, common correlation (CC, estimated correlation (EC, and multivariate multilevel correlation (MMC on the estimation bias, mean square error (MSE, and 95% probability coverage of the confidence interval (CI in the synthesis of Cox proportional hazard models coefficients in a simulation study. Result. Comparing the results of the simulation study on the MSE, bias, and CI of the estimated coefficients indicated that MMC approach was the most accurate procedure compared to EC, CC, and ZC procedures. The precision ranking of the four approaches according to all above settings was MMC ≥ EC ≥ CC ≥ ZC. Conclusion. This study highlights advantages of MGLS meta-analysis on UM approach. The results suggested the use of MMC procedure to overcome the lack of information for having a complete covariance matrix of the coefficients.

The Covariance Adjustment Approaches for Combining Incomparable Cox Regressions Caused by Unbalanced Covariates Adjustment: A Multivariate Meta-Analysis Study.

Science.gov (United States)

Dehesh, Tania; Zare, Najaf; Ayatollahi, Seyyed Mohammad Taghi

2015-01-01

Univariate meta-analysis (UM) procedure, as a technique that provides a single overall result, has become increasingly popular. Neglecting the existence of other concomitant covariates in the models leads to loss of treatment efficiency. Our aim was proposing four new approximation approaches for the covariance matrix of the coefficients, which is not readily available for the multivariate generalized least square (MGLS) method as a multivariate meta-analysis approach. We evaluated the efficiency of four new approaches including zero correlation (ZC), common correlation (CC), estimated correlation (EC), and multivariate multilevel correlation (MMC) on the estimation bias, mean square error (MSE), and 95% probability coverage of the confidence interval (CI) in the synthesis of Cox proportional hazard models coefficients in a simulation study. Comparing the results of the simulation study on the MSE, bias, and CI of the estimated coefficients indicated that MMC approach was the most accurate procedure compared to EC, CC, and ZC procedures. The precision ranking of the four approaches according to all above settings was MMC ≥ EC ≥ CC ≥ ZC. This study highlights advantages of MGLS meta-analysis on UM approach. The results suggested the use of MMC procedure to overcome the lack of information for having a complete covariance matrix of the coefficients.

Network meta-analysis-highly attractive but more methodological research is needed

Directory of Open Access Journals (Sweden)

Singh Sonal

2011-06-01

Full Text Available Abstract Network meta-analysis, in the context of a systematic review, is a meta-analysis in which multiple treatments (that is, three or more are being compared using both direct comparisons of interventions within randomized controlled trials and indirect comparisons across trials based on a common comparator. To ensure validity of findings from network meta-analyses, the systematic review must be designed rigorously and conducted carefully. Aspects of designing and conducting a systematic review for network meta-analysis include defining the review question, specifying eligibility criteria, searching for and selecting studies, assessing risk of bias and quality of evidence, conducting a network meta-analysis, interpreting and reporting findings. This commentary summarizes the methodologic challenges and research opportunities for network meta-analysis relevant to each aspect of the systematic review process based on discussions at a network meta-analysis methodology meeting we hosted in May 2010 at the Johns Hopkins Bloomberg School of Public Health. Since this commentary reflects the discussion at that meeting, it is not intended to provide an overview of the field.

Prognostic value of C-reactive protein levels in patients with bone neoplasms: A meta-analysis.

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Li, Wenyi; Luo, Xujun; Liu, Zhongyue; Chen, Yanqiao; Li, Zhihong

2018-01-01

The aim of this study was to conduct a meta-analysis of retrospective studies that investigated the association of preoperative C-reactive protein (CRP) levels with the overall survival (OS) of patients with bone neoplasms. A detailed literature search was performed in the Cochrane Library, Web of Science, Embase and PubMed databases up to August 28, 2017, for related research publications written in English. We extracted the data from these studies and combined the hazard ratios (HR) and 95% confidence intervals (CIs) to assess the correlation between CRP levels and OS in patients with bone neoplasms. Five studies with a total of 816 participants from several countries were enrolled in this current meta-analysis. In a pooled analysis of all the publications, increased serum CRP levels had an adverse prognostic effect on the overall survival of patients with bone neoplasms. However, the combined data showed no significant relationship between the level of CRP and OS in Asian patients (HR = 1.73; 95% CI: 0.86-3.49; P = 0.125). Similar trends were observed in patients with bone neoplasms when stratified by ethnicity, histology, metastasis and study sample size. The results of this meta-analysis suggest that increased CRP expression indicates a poorer prognosis in patients with bone neoplasms. More prospective studies are needed to confirm the prognostic significance of CRP levels in patients with bone neoplasms.

Occupational and environmental scleroderma. Systematic review and meta-analysis.

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Rubio-Rivas, Manuel; Moreno, Rafael; Corbella, Xavier

2017-03-01

The etiology of systemic sclerosis (SSc) remains unknown; however, several occupational and environmental factors have been implicated. Our objective was to perform a meta-analysis of all studies published on SSc associated with occupational and environmental exposure. The review was undertaken by means of MEDLINE and SCOPUS from 1960 to 2014 and using the terms: "systemic," "scleroderma," or "systemic sclerosis/chemically induced" [MesH]. The Newcastle-Ottawa Scale was used for the qualifying assessment. The inverse variance-weighted method was performed. The meta-analysis of silica exposure included 15 case-control studies [overall OR 2.81 (95%CI 1.86-4.23; p < 0.001)] and 4 cohort studies [overall RR 17.52 (95%CI 5.98-51.37; p < 0.001)]; the meta-analysis of solvents exposure included 13 case-control studies (overall OR 2.00 [95%CI 1.32-3.02; p = 0.001); the meta-analysis of breast implants exposure included 4 case-control studies (overall OR 1.68 (95%CI 1.65-1.71; p < 0.001)) and 6 cohort studies (overall RR 2.13 (95%CI 0.86-5.27; p = 0.10)); the meta-analysis of epoxy resins exposure included 4 case-control studies (overall OR 2.97 (95%CI 2.31-3.83; p < 0.001)), the meta-analysis of pesticides exposure included 3 case-control studies (overall OR 1.02 (95%CI 0.78-1.32; p = 0.90)) and, finally, the meta-analysis of welding fumes exposure included 4 studies (overall OR 1.29 (95%CI 0.44-3.74; p = 0.64)). Not enough studies citing risks related to hair dyes have been published to perform an accurate meta-analysis. Silica and solvents were the two most likely substances related to the pathogenesis of SSc. While silica is involved in particular jobs, solvents are widespread and more people are at risk of having incidental contact with them.

A novel bi-level meta-analysis approach: applied to biological pathway analysis.

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Nguyen, Tin; Tagett, Rebecca; Donato, Michele; Mitrea, Cristina; Draghici, Sorin

2016-02-01

The accumulation of high-throughput data in public repositories creates a pressing need for integrative analysis of multiple datasets from independent experiments. However, study heterogeneity, study bias, outliers and the lack of power of available methods present real challenge in integrating genomic data. One practical drawback of many P-value-based meta-analysis methods, including Fisher's, Stouffer's, minP and maxP, is that they are sensitive to outliers. Another drawback is that, because they perform just one statistical test for each individual experiment, they may not fully exploit the potentially large number of samples within each study. We propose a novel bi-level meta-analysis approach that employs the additive method and the Central Limit Theorem within each individual experiment and also across multiple experiments. We prove that the bi-level framework is robust against bias, less sensitive to outliers than other methods, and more sensitive to small changes in signal. For comparative analysis, we demonstrate that the intra-experiment analysis has more power than the equivalent statistical test performed on a single large experiment. For pathway analysis, we compare the proposed framework versus classical meta-analysis approaches (Fisher's, Stouffer's and the additive method) as well as against a dedicated pathway meta-analysis package (MetaPath), using 1252 samples from 21 datasets related to three human diseases, acute myeloid leukemia (9 datasets), type II diabetes (5 datasets) and Alzheimer's disease (7 datasets). Our framework outperforms its competitors to correctly identify pathways relevant to the phenotypes. The framework is sufficiently general to be applied to any type of statistical meta-analysis. The R scripts are available on demand from the authors. sorin@wayne.edu Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e

Synergistic effect of anti-angiogenic herbal composition (Meta-X) in combination with radiotherapy on the inhibition of tumor growth

International Nuclear Information System (INIS)

Han, Young Soo; Song, Jie Young; Yoon, Yeon Sook; Kim, Joon Sik; Park, Byung Young; Lee, Hee Suk; Kim, Min Yung

2004-01-01

Anti-angiogenic composition called Meta-X was made from herbal medicines that are currently used oral drugs for other indications. We examined biochemical properties of Meta-X, and synergistic effect of Meta-X combined with irradiation on the inhibition of tumor growth

Synergistic effect of anti-angiogenic herbal composition (Meta-X) in combination with radiotherapy on the inhibition of tumor growth

Energy Technology Data Exchange (ETDEWEB)

Han, Young Soo; Song, Jie Young; Yoon, Yeon Sook [Korea Institute of Radilolgical and Medical Science, Seoul (Korea, Republic of); Kim, Joon Sik; Park, Byung Young; Lee, Hee Suk; Kim, Min Yung [AngioLab, Seoul (Korea, Republic of)

2004-07-01

Anti-angiogenic composition called Meta-X was made from herbal medicines that are currently used oral drugs for other indications. We examined biochemical properties of Meta-X, and synergistic effect of Meta-X combined with irradiation on the inhibition of tumor growth.

Mass meta-analysis in Talairach space

DEFF Research Database (Denmark)

Nielsen, Finn Årup

2004-01-01

We provide a method for mass meta-analysis in a neuroinformatics database containing stereotaxic Talairach coordinates from neuroimaging experiments. Database labels are used to group the individual experiments, e.g., according to cognitive function, and the consistent pattern of the experiments...... of experiments, and the distances to the null hypotheses are used to sort the voxels across groups of experiments. This allows for mass meta-analysis, with the construction of a list with the most prominent associations between brain areas and group labels. Furthermore, the method can be used for functional...

Curcuminoids Lower Plasma Leptin Concentrations: A Meta-analysis.

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Atkin, Stephen L; Katsiki, Niki; Derosa, Giuseppe; Maffioli, Pamela; Sahebkar, Amirhossein

2017-12-01

Curcumin is a naturally occurring polyphenol that has been suggested to improve several metabolic diseases. Leptin is an adipokine involved in metabolic status and appetite, with marked crosstalk with other systems. Available data suggest that curcumin may affect leptin levels; therefore, this meta-analysis was performed to evaluate this. A systematic review and meta-analysis were undertaken on all randomized controlled trials of curcumin studies that included the measurement of leptin. The search included PubMed-Medline, Scopus, ISI Web of Knowledge, and Google Scholar databases. Quantitative data synthesis was performed by using a random-effects model, with standardized mean difference and 95% confidence interval as summary statistics. A funnel plot, Begg's rank correlation, and Egger's weighted regression tests assessed the presence of publication bias. Four eligible articles comprising five treatment arms were selected for the meta-analysis. Meta-analysis showed a significant decrease in plasma leptin concentrations following curcumin treatment (standardized mean difference: -0.69, 95% confidence interval: -1.16, -0.23, p = 0.003; I 2  = 76.53%). There was no evidence of publication bias. This meta-analysis showed that curcumin supplementation is associated with a decrease in leptin levels that may be regarded as a potential mechanism for the metabolic effects of curcumin. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Natural funnel asymmetries. A simulation analysis of the three basic tools of meta analysis

DEFF Research Database (Denmark)

Callot, Laurent Abdelkader Francois; Paldam, Martin

Meta-analysis studies a set of estimates of one parameter with three basic tools: The funnel diagram is the distribution of the estimates as a function of their precision; the funnel asymmetry test, FAT; and the meta average, where PET is an estimate. The FAT-PET MRA is a meta regression analysis...

Using Meta-Analysis to Inform the Design of Subsequent Studies of Diagnostic Test Accuracy

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Hinchliffe, Sally R.; Crowther, Michael J.; Phillips, Robert S.; Sutton, Alex J.

2013-01-01

An individual diagnostic accuracy study rarely provides enough information to make conclusive recommendations about the accuracy of a diagnostic test; particularly when the study is small. Meta-analysis methods provide a way of combining information from multiple studies, reducing uncertainty in the result and hopefully providing substantial…

Comparing Active Pediatric Obesity Treatments Using Meta-Analysis

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Gilles, Allyson; Cassano, Michael; Shepherd, Elizabeth J.; Higgins, Diana; Hecker, Jeffrey E.; Nangle, Douglas W.

2008-01-01

The current meta-analysis reviews research on the treatment of pediatric obesity focusing on studies that have been published since 1994. Eleven studies (22 comparisons, 115 effect sizes, N = 447) were included in the present meta-analysis. Results indicated that comprehensive behavioral interventions may be improved in at least two ways:…

A meta-analysis of hyperfractionated and accelerated radiotherapy and combined chemotherapy and radiotherapy regimens in unresected locally advanced squamous cell carcinoma of the head and neck

International Nuclear Information System (INIS)

Budach, W; Hehr, T; Budach, V; Belka, C; Dietz, K

2006-01-01

Former meta-analyses have shown a survival benefit for the addition of chemotherapy (CHX) to radiotherapy (RT) and to some extent also for the use of hyperfractionated radiation therapy (HFRT) and accelerated radiation therapy (AFRT) in locally advanced squamous cell carcinoma (SCC) of the head and neck. However, the publication of new studies and the fact that many older studies that were included in these former meta-analyses used obsolete radiation doses, CHX schedules or study designs prompted us to carry out a new analysis using strict inclusion criteria. Randomised trials testing curatively intended RT (≥60 Gy in >4 weeks/>50 Gy in <4 weeks) on SCC of the oral cavity, oropharynx, hypopharynx, and larynx published as full paper or in abstract form between 1975 and 2003 were eligible. Trials comparing RT alone with concurrent or alternating chemoradiation (5-fluorouracil (5-FU), cisplatin, carboplatin, mitomycin C) were analyzed according to the employed radiation schedule and the used CHX regimen. Studies comparing conventionally fractionated radiotherapy (CFRT) with either HFRT or AFRT without CHX were separately examined. End point of the meta-analysis was overall survival. Thirty-two trials with a total of 10 225 patients were included into the meta-analysis. An overall survival benefit of 12.0 months was observed for the addition of simultaneous CHX to either CFRT or HFRT/AFRT (p < 0.001). Separate analyses by cytostatic drug indicate a prolongation of survival of 24.0 months, 16.8 months, 6.7 months, and 4.0 months, respectively, for the simultaneous administration of 5-FU, cisplatin-based, carboplatin-based, and mitomycin C-based CHX to RT (each p < 0.01). Whereas no significant gain in overall survival was observed for AFRT in comparison to CFRT, a substantial prolongation of median survival (14.2 months, p < 0.001) was seen for HFRT compared to CFRT (both without CHX). RT combined with simultaneous 5-FU, cisplatin, carboplatin, and mitomycin C as

Meta-analysis for evidence synthesis in plant pathology: an overview.

Science.gov (United States)

Madden, L V; Paul, P A

2011-01-01

Meta-analysis is the analysis of the results of multiple studies, which is typically performed in order to synthesize evidence from many possible sources in a formal probabilistic manner. In a simple sense, the outcome of each study becomes a single observation in the meta-analysis of all available studies. The methodology was developed originally in the social sciences by Smith, Glass, Rosenthal, Hunter, and Schmidt, based on earlier pioneering contributions in statistics by Fisher, Pearson, Yates, and Cochran, but this approach to research synthesis has now been embraced within many scientific disciplines. However, only a handful of articles have been published in plant pathology and related fields utilizing meta-analysis. After reviewing basic concepts and approaches, methods for estimating parameters and interpreting results are shown. The advantages of meta-analysis are presented in terms of prediction and risk analysis, and the high statistical power that can be achieved for detecting significant effects of treatments or significant relationships between variables. Based on power considerations, the fallacy of naïve counting of P values in a narrative review is demonstrated. Although there are many advantages to meta-analysis, results can be biased if the analysis is based on a nonrepresentative sample of study outcomes. Therefore, novel approaches for characterizing the upper bound on the bias are discussed, in order to show the robustness of meta-analysis to possible violation of assumptions.

Efficacy and safety of interscalene block combined with general anesthesia for arthroscopic shoulder surgery: A meta-analysis.

Science.gov (United States)

Yan, Siyi; Zhao, Yanjun; Zhang, Huan

2018-06-01

There is controversy regarding the efficacy and safety of using interscalene block (ISB) combined with general anesthesia (GA) for arthroscopic shoulder surgery. Our meta-analysis was undertaken to evaluate the utility of this approach. We searched the PubMed, Cochrane Library, EMBASE, CNKI, VIP and ClinicalTrials.gov databases for randomized controlled trials. The primary endpoint was extubation time. Secondary endpoints included intraoperative heart rate, pain scores on the day of and 1 day after the operation, intraoperative systolic blood pressure and adverse events. Ten RCTs involving 746 patients undergoing arthroscopic shoulder surgery met inclusion criteria. Compared with GA alone, ISB + GA was associated with a shorter extubation time(WMD = -6.13; 95% CI = -8.68 to -3.57; P shoulder surgery, ISB + GA is associated with a lower heart rate, lower pain scores on the day of and 1 day after the operation, a lower intraoperative systolic blood pressure, a shorter extubation time and a lower incidence of adverse events compared with GA alone. Copyright © 2018 Elsevier Inc. All rights reserved.

A systematic review of the effectiveness of CBT/ERP group therapy of OCD: A meta-analysis

DEFF Research Database (Denmark)

Jónsson, Hjalti; Hougaard, Esben; Bennedsen, Birgit

, as well as reviewers of the literature have focused on within single treatments effect sizes rather between group effect sizes. OBJECTIVES To make a systematic review, and by methods of meta analysis compute a pooled within effect size of studies of group CBT of OCD and compare these to previously.......05 and 1.25 respectively, with an overall combined pooled within effect size across the categories at 1.18. Finally a between effect sizes of the four studies comparing group therapy to waitlist control group was reported at.1.12 CONCLUSION The reported within effect sizes in this meta-analysis (range 1...

A resampling-based meta-analysis for detection of differential gene expression in breast cancer

International Nuclear Information System (INIS)

Gur-Dedeoglu, Bala; Konu, Ozlen; Kir, Serkan; Ozturk, Ahmet Rasit; Bozkurt, Betul; Ergul, Gulusan; Yulug, Isik G

2008-01-01

Accuracy in the diagnosis of breast cancer and classification of cancer subtypes has improved over the years with the development of well-established immunohistopathological criteria. More recently, diagnostic gene-sets at the mRNA expression level have been tested as better predictors of disease state. However, breast cancer is heterogeneous in nature; thus extraction of differentially expressed gene-sets that stably distinguish normal tissue from various pathologies poses challenges. Meta-analysis of high-throughput expression data using a collection of statistical methodologies leads to the identification of robust tumor gene expression signatures. A resampling-based meta-analysis strategy, which involves the use of resampling and application of distribution statistics in combination to assess the degree of significance in differential expression between sample classes, was developed. Two independent microarray datasets that contain normal breast, invasive ductal carcinoma (IDC), and invasive lobular carcinoma (ILC) samples were used for the meta-analysis. Expression of the genes, selected from the gene list for classification of normal breast samples and breast tumors encompassing both the ILC and IDC subtypes were tested on 10 independent primary IDC samples and matched non-tumor controls by real-time qRT-PCR. Other existing breast cancer microarray datasets were used in support of the resampling-based meta-analysis. The two independent microarray studies were found to be comparable, although differing in their experimental methodologies (Pearson correlation coefficient, R = 0.9389 and R = 0.8465 for ductal and lobular samples, respectively). The resampling-based meta-analysis has led to the identification of a highly stable set of genes for classification of normal breast samples and breast tumors encompassing both the ILC and IDC subtypes. The expression results of the selected genes obtained through real-time qRT-PCR supported the meta-analysis results. The

A resampling-based meta-analysis for detection of differential gene expression in breast cancer

Directory of Open Access Journals (Sweden)

Ergul Gulusan

2008-12-01

Full Text Available Abstract Background Accuracy in the diagnosis of breast cancer and classification of cancer subtypes has improved over the years with the development of well-established immunohistopathological criteria. More recently, diagnostic gene-sets at the mRNA expression level have been tested as better predictors of disease state. However, breast cancer is heterogeneous in nature; thus extraction of differentially expressed gene-sets that stably distinguish normal tissue from various pathologies poses challenges. Meta-analysis of high-throughput expression data using a collection of statistical methodologies leads to the identification of robust tumor gene expression signatures. Methods A resampling-based meta-analysis strategy, which involves the use of resampling and application of distribution statistics in combination to assess the degree of significance in differential expression between sample classes, was developed. Two independent microarray datasets that contain normal breast, invasive ductal carcinoma (IDC, and invasive lobular carcinoma (ILC samples were used for the meta-analysis. Expression of the genes, selected from the gene list for classification of normal breast samples and breast tumors encompassing both the ILC and IDC subtypes were tested on 10 independent primary IDC samples and matched non-tumor controls by real-time qRT-PCR. Other existing breast cancer microarray datasets were used in support of the resampling-based meta-analysis. Results The two independent microarray studies were found to be comparable, although differing in their experimental methodologies (Pearson correlation coefficient, R = 0.9389 and R = 0.8465 for ductal and lobular samples, respectively. The resampling-based meta-analysis has led to the identification of a highly stable set of genes for classification of normal breast samples and breast tumors encompassing both the ILC and IDC subtypes. The expression results of the selected genes obtained through real

A Systematic Review and Meta-analysis of the Association Between Giardia lamblia and Endemic Pediatric Diarrhea in Developing Countries

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Muhsen, Khitam; Levine, Myron M.

2012-01-01

We performed a systematic literature review and meta-analysis examining the association between diarrhea in young children in nonindustrialized settings and Giardia lamblia infection. Eligible were case/control and longitudinal studies that defined the outcome as acute or persistent (>14 days) diarrhea, adjusted for confounders and lasting for at least 1 year. Data on G. lamblia detection (mainly in stools) from diarrhea patients and controls without diarrhea were abstracted. Random effects model meta-analysis obtained pooled odds ratios (ORs) and 95% confidence intervals (CIs). Twelve nonindustrialized-setting acute pediatric diarrhea studies met the meta-analysis inclusion criteria. Random-effects model meta-analysis of combined results (9774 acute diarrhea cases and 8766 controls) yielded a pooled OR of 0.60 (95% CI, .38–.94; P = .03), indicating that G. lamblia was not associated with acute diarrhea. However, limited data suggest that initial Giardia infections in early infancy may be positively associated with diarrhea. Meta-analysis of 5 persistent diarrhea studies showed a pooled OR of 3.18 (95% CI, 1.50–6.76; P diarrhea in children in developing countries. PMID:23169940

Regression and local control rates after radiotherapy for jugulotympanic paragangliomas: Systematic review and meta-analysis

International Nuclear Information System (INIS)

Hulsteijn, Leonie T. van; Corssmit, Eleonora P.M.; Coremans, Ida E.M.; Smit, Johannes W.A.; Jansen, Jeroen C.; Dekkers, Olaf M.

2013-01-01

The primary treatment goal of radiotherapy for paragangliomas of the head and neck region (HNPGLs) is local control of the tumor, i.e. stabilization of tumor volume. Interestingly, regression of tumor volume has also been reported. Up to the present, no meta-analysis has been performed giving an overview of regression rates after radiotherapy in HNPGLs. The main objective was to perform a systematic review and meta-analysis to assess regression of tumor volume in HNPGL-patients after radiotherapy. A second outcome was local tumor control. Design of the study is systematic review and meta-analysis. PubMed, EMBASE, Web of Science, COCHRANE and Academic Search Premier and references of key articles were searched in March 2012 to identify potentially relevant studies. Considering the indolent course of HNPGLs, only studies with ⩾12 months follow-up were eligible. Main outcomes were the pooled proportions of regression and local control after radiotherapy as initial, combined (i.e. directly post-operatively or post-embolization) or salvage treatment (i.e. after initial treatment has failed) for HNPGLs. A meta-analysis was performed with an exact likelihood approach using a logistic regression with a random effect at the study level. Pooled proportions with 95% confidence intervals (CI) were reported. Fifteen studies were included, concerning a total of 283 jugulotympanic HNPGLs in 276 patients. Pooled regression proportions for initial, combined and salvage treatment were respectively 21%, 33% and 52% in radiosurgery studies and 4%, 0% and 64% in external beam radiotherapy studies. Pooled local control proportions for radiotherapy as initial, combined and salvage treatment ranged from 79% to 100%. Radiotherapy for jugulotympanic paragangliomas results in excellent local tumor control and therefore is a valuable treatment for these types of tumors. The effects of radiotherapy on regression of tumor volume remain ambiguous, although the data suggest that regression can

Aromatherapy for Sexual Problems in Menopausal Women: A Systematic Review and Meta-analysis

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Khadivzadeh, Talat; Najafi, Mona Najaf; Irani, Morvarid; Dizavandi, Fatemeh Rajab; Shariati, Khatereh

2018-01-01

Objectives The aim of the present systematic review and meta-analysis is the exploration of the potential evidence of the effectiveness of aromatherapy products on the sexual function of menopausal women. Methods From inception to December 2017, the search process was performed using the MEDLINE and Scopus databases and the Cochrane Library regarding the trials on the effectiveness of herbal-medicine aromatherapy on the sexual function of menopausal women. Results Three of the trials comprise suitable data for inclusion in the meta-analysis. According to the meta-analysis, it is possible to improve the standardized mean difference (SMD) of the sexual desire up to 0.56 in the aromatherapy group compared with the control group (SMD = 0.56; P aromatherapy with neroli oil or lavender (monopreparation) and combined-oil aromatherapy with lavender, fennel, geranium, and rose significantly improved human sexual function; however, a significant change of the serum-estrogen level was not detected. The findings of the present review should be presented cautiously because of the corresponding limitations such as the lack of a standardized tool, the lack of intention-to-treat reporting, the low study amount, and the short-term follow-up. PMID:29765928

Systematic review with meta-analysis

DEFF Research Database (Denmark)

Kimer, N; Krag, A; Møller, Søren

2014-01-01

BACKGROUND: Rifaximin is recommended for prevention of hepatic encephalopathy (HE). The effects of rifaximin on overt and minimal HE are debated. AIM: To perform a systematic review and meta-analysis of randomised controlled trials (RCTs) on rifaximin for HE. METHODS: We performed electronic...... and manual searches, gathered information from the U.S. Food and Drug Administration Home Page, and obtained unpublished information on trial design and outcome measures from authors and pharmaceutical companies. Meta-analyses were performed and results presented as risk ratios (RR) with 95% confidence...

Systematic review with meta-analysis

DEFF Research Database (Denmark)

Roda, G; Narula, N; Pinotti, R

2017-01-01

and meta-analysis of epidemiological studies reporting on extension of ulcerative colitis to determine frequency of disease extension in patients with limited ulcerative colitis at diagnosis. METHODS: We performed a systematic literature search to identify studies on disease extension of ulcerative colitis...... (UC) and predictors of disease progression. RESULTS: Overall, 41 studies were eligible for systematic review but only 30 for meta-analysis. The overall pooled frequency of UC extension was 22.8% with colonic extension being 17.8% at 5 years and 31% at 10 years. Extension was 17.8% (95% CI 11...... in patients from North America (37.8%) than from Europe (19.6%) (Pmeta-analysis, approximately one quarter of patients with limited UC extend over time with most extension occurring during the first 10 years. Rate of extension depends on age at diagnosis and geographic origin...

A systemic review and meta-analysis of the clinical efficacy and safety of total glucosides of peony combined with methotrexate in rheumatoid arthritis.

Science.gov (United States)

Feng, Zhi-Tao; Xu, Juan; He, Guo-Chao; Cai, San-Jin; Li, Juan; Mei, Zhi-Gang

2018-01-01

To assess the efficacy and safety of the combination of total glucoside of peony (TGP) and methotrexate (MTX) for the treatment of rheumatoid arthritis (RA). Randomized controlled trial (RCT) data on the traditional Chinese active component TGP combined with MTX vs. MTX alone for the treatment of RA was collected by searching the Pubmed, Embase, Cochrane Library, CNKI, VIP Journals database, and Wanfang database up to February 2017. Study selection, data extraction, data synthesis, and data analyses were performed according to the Cochrane standards. A total of eight RCTs involving 522 participants were included in this meta-analysis. Compared with MTX alone, the use of TGP combined with MTX exhibited better therapeutic effects for the treatment of RA (P = 0.004). In addition, TGP combined with MTX caused a more significant decrease in erythrocyte sedimentation rate (ESR) (P TGP and MTX combination group (P = 0.0007). Our study demonstrates that TGP combined with MTX is more effective than MTX alone for the treatment of RA. Nevertheless, the adverse effects of the combination of TGP and MTX need to be further assessed. Due to the poor methodological quality of included trials, well-designed, multi-center, and large-scale RCTs are necessary to draw a more definitive conclusion.

ABERRANT RESTING-STATE BRAIN ACTIVITY IN POSTTRAUMATIC STRESS DISORDER: A META-ANALYSIS AND SYSTEMATIC REVIEW.

Science.gov (United States)

Koch, Saskia B J; van Zuiden, Mirjam; Nawijn, Laura; Frijling, Jessie L; Veltman, Dick J; Olff, Miranda

2016-07-01

About 10% of trauma-exposed individuals develop PTSD. Although a growing number of studies have investigated resting-state abnormalities in PTSD, inconsistent results suggest a need for a meta-analysis and a systematic review. We conducted a systematic literature search in four online databases using keywords for PTSD, functional neuroimaging, and resting-state. In total, 23 studies matched our eligibility criteria. For the meta-analysis, we included 14 whole-brain resting-state studies, reporting data on 663 participants (298 PTSD patients and 365 controls). We used the activation likelihood estimation approach to identify concurrence of whole-brain hypo- and hyperactivations in PTSD patients during rest. Seed-based studies could not be included in the quantitative meta-analysis. Therefore, a separate qualitative systematic review was conducted on nine seed-based functional connectivity studies. The meta-analysis showed consistent hyperactivity in the ventral anterior cingulate cortex and the parahippocampus/amygdala, but hypoactivity in the (posterior) insula, cerebellar pyramis and middle frontal gyrus in PTSD patients, compared to healthy controls. Partly concordant with these findings, the systematic review on seed-based functional connectivity studies showed enhanced salience network (SN) connectivity, but decreased default mode network (DMN) connectivity in PTSD. Combined, these altered resting-state connectivity and activity patterns could represent neurobiological correlates of increased salience processing and hypervigilance (SN), at the cost of awareness of internal thoughts and autobiographical memory (DMN) in PTSD. However, several discrepancies between findings of the meta-analysis and systematic review were observed, stressing the need for future studies on resting-state abnormalities in PTSD patients. © 2016 Wiley Periodicals, Inc.

Meta-analysis of the efficacy and safety of combined surgery in the management of eyes with coexisting cataract and open angle glaucoma

Directory of Open Access Journals (Sweden)

Nan Jiang

2018-02-01

Full Text Available AIM: To conduct a systematic review and quantitative Meta-analysis of the efficacy and safety of combined surgery for the eyes with coexisting cataract and open angle glaucoma. METHODS: We performed a systematic search of the related literature in the Cochrane Library, PubMed, EMBASE, Web of Science databases, CNKI, CBM and Wan Fang databases, with no limitations on language or publication date. The primary efficacy estimate was identified by weighted mean difference of the percentage of intraocular pressure reduction (IOPR% from baseline to end-point, the percentage of number of glaucoma medications reduction from pre- to post-operation, and the secondary efficacy evaluations were performed by odds ratio (OR and 95% confidence interval (CI for complete and qualified success rate. Besides, ORs were applied to assess the tolerability of adverse incidents. Meta-analyses of fixed or random effect models were performed using RevMan software 5.2 to gather the consequences. Heterogeneity was evaluated by Chi2 test and the I2 measure. RESULTS: Ten studies enrolling 3108 patients were included. The combined consequences indicated that both glaucoma and combined cataract and glaucoma surgery significantly decreased IOP. For deep sclerectomy vs deep sclerectomy plus phacoemulsification and canaloplasty vs phaco-canaloplasty, the differences in IOPR% were not all statistically significant while trabeculotomy was detected to gain a quantitatively greater IOPR% compared with trabeculotomy plus phacoemulsification. Furthermore, there was no statistical significance in the complete and qualified success rate, and the rates of adverse incidents for trabeculotomy vs trabeculotomy plus phacoemulsification. CONCLUSION: Compared with trabeculotomy plus phacoemulsification, trabeculectomy alone is more effective in lowering IOP and the number of glaucoma medications, while the two surgeries can not demonstrate statistical differences in the complete success rate

Meta-analysis of the efficacy and safety of combined surgery in the management of eyes with coexisting cataract and open angle glaucoma.

Science.gov (United States)

Jiang, Nan; Zhao, Gui-Qiu; Lin, Jing; Hu, Li-Ting; Che, Cheng-Ye; Wang, Qian; Xu, Qiang; Li, Cui; Zhang, Jie

2018-01-01

To conduct a systematic review and quantitative Meta-analysis of the efficacy and safety of combined surgery for the eyes with coexisting cataract and open angle glaucoma. We performed a systematic search of the related literature in the Cochrane Library, PubMed, EMBASE, Web of Science databases, CNKI, CBM and Wan Fang databases, with no limitations on language or publication date. The primary efficacy estimate was identified by weighted mean difference of the percentage of intraocular pressure reduction (IOPR%) from baseline to end-point, the percentage of number of glaucoma medications reduction from pre- to post-operation, and the secondary efficacy evaluations were performed by odds ratio (OR) and 95% confidence interval (CI) for complete and qualified success rate. Besides, ORs were applied to assess the tolerability of adverse incidents. Meta-analyses of fixed or random effect models were performed using RevMan software 5.2 to gather the consequences. Heterogeneity was evaluated by Chi 2 test and the I 2 measure. Ten studies enrolling 3108 patients were included. The combined consequences indicated that both glaucoma and combined cataract and glaucoma surgery significantly decreased IOP. For deep sclerectomy vs deep sclerectomy plus phacoemulsification and canaloplasty vs phaco-canaloplasty, the differences in IOPR% were not all statistically significant while trabeculotomy was detected to gain a quantitatively greater IOPR% compared with trabeculotomy plus phacoemulsification. Furthermore, there was no statistical significance in the complete and qualified success rate, and the rates of adverse incidents for trabeculotomy vs trabeculotomy plus phacoemulsification. Compared with trabeculotomy plus phacoemulsification, trabeculectomy alone is more effective in lowering IOP and the number of glaucoma medications, while the two surgeries can not demonstrate statistical differences in the complete success rate, qualified success rate, or incidence of adverse

C-reactive protein gene polymorphisms and myocardial infarction risk: a meta-analysis and meta-regression.

Science.gov (United States)

Zhu, Yanbin; Liu, Tongku; He, Haitao; Sun, Yuqing; Zhuo, Fengling

2013-12-01

C-reactive protein (CRP), the classic acute-phase protein, plays an important role in the etiology of myocardial infarction (MI). Emerging evidence has shown that the common polymorphisms in the CRP gene may influence an individual's susceptibility to MI; but individually published studies showed inconclusive results. This meta-analysis aimed to derive a more precise estimation of the associations between CRP gene polymorphisms and MI risk. A literature search of PubMed, Embase, Web of Science, and China BioMedicine (CBM) databases was conducted on articles published before June 1st, 2013. Crude odds ratio (OR) with 95% confidence interval (CI) were calculated. Nine case-control studies were included with a total of 2992 MI patients and 4711 healthy controls. The meta-analysis results indicated that CRP rs3093059 (T>C) polymorphism was associated with decreased risk of MI, especially among Asian populations. However, similar associations were not observed in CRP rs1800947 (G>C) and rs2794521 (G>A) polymorphisms (all p>0.05) among both Asian and Caucasian populations. Univariate and multivariate meta-regression analyses showed that ethnicity may be a major source of heterogeneity. No publication bias was detected in this meta-analysis. In conclusion, the current meta-analysis indicates that CRP rs3093059 (T>C) polymorphism may be associated with decreased risk of MI, especially among Asian populations.

A framework for the meta-analysis of Bland-Altman studies based on a limits of agreement approach.

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Tipton, Elizabeth; Shuster, Jonathan

2017-10-15

Bland-Altman method comparison studies are common in the medical sciences and are used to compare a new measure to a gold-standard (often costlier or more invasive) measure. The distribution of these differences is summarized by two statistics, the 'bias' and standard deviation, and these measures are combined to provide estimates of the limits of agreement (LoA). When these LoA are within the bounds of clinically insignificant differences, the new non-invasive measure is preferred. Very often, multiple Bland-Altman studies have been conducted comparing the same two measures, and random-effects meta-analysis provides a means to pool these estimates. We provide a framework for the meta-analysis of Bland-Altman studies, including methods for estimating the LoA and measures of uncertainty (i.e., confidence intervals). Importantly, these LoA are likely to be wider than those typically reported in Bland-Altman meta-analyses. Frequently, Bland-Altman studies report results based on repeated measures designs but do not properly adjust for this design in the analysis. Meta-analyses of Bland-Altman studies frequently exclude these studies for this reason. We provide a meta-analytic approach that allows inclusion of estimates from these studies. This includes adjustments to the estimate of the standard deviation and a method for pooling the estimates based upon robust variance estimation. An example is included based on a previously published meta-analysis. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

A non-parametric meta-analysis approach for combining independent microarray datasets: application using two microarray datasets pertaining to chronic allograft nephropathy

Directory of Open Access Journals (Sweden)

Archer Kellie J

2008-02-01

Full Text Available Abstract Background With the popularity of DNA microarray technology, multiple groups of researchers have studied the gene expression of similar biological conditions. Different methods have been developed to integrate the results from various microarray studies, though most of them rely on distributional assumptions, such as the t-statistic based, mixed-effects model, or Bayesian model methods. However, often the sample size for each individual microarray experiment is small. Therefore, in this paper we present a non-parametric meta-analysis approach for combining data from independent microarray studies, and illustrate its application on two independent Affymetrix GeneChip studies that compared the gene expression of biopsies from kidney transplant recipients with chronic allograft nephropathy (CAN to those with normal functioning allograft. Results The simulation study comparing the non-parametric meta-analysis approach to a commonly used t-statistic based approach shows that the non-parametric approach has better sensitivity and specificity. For the application on the two CAN studies, we identified 309 distinct genes that expressed differently in CAN. By applying Fisher's exact test to identify enriched KEGG pathways among those genes called differentially expressed, we found 6 KEGG pathways to be over-represented among the identified genes. We used the expression measurements of the identified genes as predictors to predict the class labels for 6 additional biopsy samples, and the predicted results all conformed to their pathologist diagnosed class labels. Conclusion We present a new approach for combining data from multiple independent microarray studies. This approach is non-parametric and does not rely on any distributional assumptions. The rationale behind the approach is logically intuitive and can be easily understood by researchers not having advanced training in statistics. Some of the identified genes and pathways have been

Graphics and Statistics for Cardiology: Data visualisation for meta-analysis.

Science.gov (United States)

Kiran, Amit; Crespillo, Abel Pérez; Rahimi, Kazem

2017-01-01

Graphical displays play a pivotal role in understanding data sets and disseminating results. For meta-analysis, they are instrumental in presenting findings from multiple studies. This report presents guidance to authors wishing to submit graphical displays as part of their meta-analysis to a clinical cardiology journal, such as HeartWhen using graphical displays for meta-analysis, we recommend the following: Use a flow diagram to describe the number of studies returned from the initial search, the inclusion/exclusion criteria applied and the final number of studies used in the meta-analysis.Present results from the meta-analysis using a figure that incorporates a forest plot and underlying (tabulated) statistics, including test for heterogeneity.Use displays such as funnel plot (minimum 10 studies) and Galbraith plot to visually present distribution of effect sizes or associations in order to evaluate small-study effects and publication bias).For meta-regression, the bubble plot is a useful display for assessing associations by study-level factors.Final checks on graphs, such as appropriate use of axis scale, line pattern, text size and graph resolution, should always be performed. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Road safety effects of roundabouts: A meta-analysis.

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Elvik, Rune

2017-02-01

This paper presents a meta-analysis of the road safety effects of converting junctions to roundabouts. 44 studies containing a total of 154 estimates of effect were included. Based on a meta-regression analysis, converting junctions to roundabouts is associated with a reduction of fatal accidents of about 65% and a reduction of injury accidents of about 40%. The mean effect on property-damage-only accidents is ambiguous. Summary estimates of effect are robust for fatal and injury accidents, but vary depending on the model of meta-analysis and the treatment of outlying data points for property-damage-only accidents. A trim-and-fill analysis suggests a weak tendency for publication bias, with modest influence on summary estimates of effect. It is concluded that roundabouts are very effective in reducing traffic fatalities. Copyright © 2016 Elsevier Ltd. All rights reserved.

Systematic reviews with meta-analysis: Why, when, and how?

NARCIS (Netherlands)

Crocetti, E.

2016-01-01

Systematic reviews with meta-analysis represent the gold standard for conducting reliable and transparent reviews of the literature. The purpose of this article is threefold: (a) to address why and when it is worthwhile to conduct a systematic review with meta-analysis, covering advantages of this

Integration of machine learning and meta-analysis identifies the transcriptomic bio-signature of mastitis disease in cattle.

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Sharifi, Somayeh; Pakdel, Abbas; Ebrahimi, Mansour; Reecy, James M; Fazeli Farsani, Samaneh; Ebrahimie, Esmaeil

2018-01-01

Gram-negative bacteria such as Escherichia coli (E. coli) are assumed to be among the main agents that cause severe mastitis disease with clinical signs in dairy cattle. Rapid detection of this disease is so important in order to prevent transmission to other cows and helps to reduce inappropriate use of antibiotics. With the rapid progress in high-throughput technologies, and accumulation of various kinds of '-omics' data in public repositories, there is an opportunity to retrieve, integrate, and reanalyze these resources to improve the diagnosis and treatment of different diseases and to provide mechanistic insights into host resistance in an efficient way. Meta-analysis is a relatively inexpensive option with good potential to increase the statistical power and generalizability of single-study analysis. In the current meta-analysis research, six microarray-based studies that investigate the transcriptome profile of mammary gland tissue after induced mastitis by E. coli infection were used. This meta-analysis not only reinforced the findings in individual studies, but also several novel terms including responses to hypoxia, response to drug, anti-apoptosis and positive regulation of transcription from RNA polymerase II promoter enriched by up-regulated genes. Finally, in order to identify the small sets of genes that are sufficiently informative in E. coli mastitis, the differentially expressed gene introduced by meta-analysis were prioritized by using ten different attribute weighting algorithms. Twelve meta-genes were detected by the majority of attribute weighting algorithms (with weight above 0.7) as most informative genes including CXCL8 (IL8), NFKBIZ, HP, ZC3H12A, PDE4B, CASP4, CXCL2, CCL20, GRO1(CXCL1), CFB, S100A9, and S100A8. Interestingly, the results have been demonstrated that all of these genes are the key genes in the immune response, inflammation or mastitis. The Decision tree models efficiently discovered the best combination of the meta-genes as

Hypothyroidism and carpal tunnel syndrome: a meta-analysis.

Science.gov (United States)

Shiri, Rahman

2014-12-01

This study aimed to assess the magnitude of the association between hypothyroidism and carpal tunnel syndrome (CTS). Eighteen studies were included in a random-effects meta-analysis. A meta-analysis of the studies that did not control their estimates for any confounder showed an association between a thyroid disease (hypo- or hyperthyroidism) and CTS (N = 9,573, effect size [ES] = 1.32 (95% confidence interval [CI], 1.04-1.68) and between hypothyroidism and CTS (N = 64,531, ES = 2.15 [95% CI, 1.64-2.83]). When a meta-analysis limited to the studies that controlled their estimates for some potential confounders, the association between a thyroid disease and CTS disappeared (N = 4,799, ES = 1.17 [95% CI, 0.71-1.92], I(2) = 0%), and the effect size for hypothyroidism largely attenuated (N = 71,133, ES = 1.44 [95% CI, 1.27-1.63], I(2) = 0%). Moreover, there was evidence of publication bias. This meta-analysis found only a modest association between hypothyroidism and CTS. Confounding and publication bias may still account for part of the remaining excess risk. © 2014 Wiley Periodicals, Inc.

Moyer's method of mixed dentition analysis: a meta-analysis ...

African Journals Online (AJOL)

The applicability of tables derived from the data Moyer used to other ethnic groups has ... This implies that Moyer's method of prediction may have population variations. ... Key Words: meta-analysis, mixed dentition analysis, Moyer's method

A Western Dietary Pattern Increases Prostate Cancer Risk: A Systematic Review and Meta-Analysis.

Science.gov (United States)

Fabiani, Roberto; Minelli, Liliana; Bertarelli, Gaia; Bacci, Silvia

2016-10-12

Dietary patterns were recently applied to examine the relationship between eating habits and prostate cancer (PC) risk. While the associations between PC risk with the glycemic index and Mediterranean score have been reviewed, no meta-analysis is currently available on dietary patterns defined by "a posteriori" methods. A literature search was carried out (PubMed, Web of Science) to identify studies reporting the relationship between dietary patterns and PC risk. Relevant dietary patterns were selected and the risks estimated were calculated by a random-effect model. Multivariable-adjusted odds ratios (ORs), for a first-percentile increase in dietary pattern score, were combined by a dose-response meta-analysis. Twelve observational studies were included in the meta-analysis which identified a "Healthy pattern" and a "Western pattern". The Healthy pattern was not related to PC risk (OR = 0.96; 95% confidence interval (CI): 0.88-1.04) while the Western pattern significantly increased it (OR = 1.34; 95% CI: 1.08-1.65). In addition, the "Carbohydrate pattern", which was analyzed in four articles, was positively associated with a higher PC risk (OR = 1.64; 95% CI: 1.35-2.00). A significant linear trend between the Western ( p = 0.011) pattern, the Carbohydrate ( p = 0.005) pattern, and the increment of PC risk was observed. The small number of studies included in the meta-analysis suggests that further investigation is necessary to support these findings.

Examining Psychokinesis: The Interaction of Human Intention with Random Number Generators--A Meta-Analysis

Science.gov (United States)

Bosch, Holger; Steinkamp, Fiona; Boller, Emil

2006-01-01

Seance-room and other large-scale psychokinetic phenomena have fascinated humankind for decades. Experimental research has reduced these phenomena to attempts to influence (a) the fall of dice and, later, (b) the output of random number generators (RNGs). The meta-analysis combined 380 studies that assessed whether RNG output correlated with human…

CrossFit Overview: Systematic Review and Meta-analysis.

Science.gov (United States)

Claudino, João Gustavo; Gabbett, Tim J; Bourgeois, Frank; Souza, Helton de Sá; Miranda, Rafael Chagas; Mezêncio, Bruno; Soncin, Rafael; Cardoso Filho, Carlos Alberto; Bottaro, Martim; Hernandez, Arnaldo Jose; Amadio, Alberto Carlos; Serrão, Julio Cerca

2018-02-26

CrossFit is recognized as one of the fastest growing high-intensity functional training modes in the world. However, scientific data regarding the practice of CrossFit is sparse. Therefore, the objective of this study is to analyze the findings of scientific literature related to CrossFit via systematic review and meta-analysis. Systematic searches of the PubMed, Web of Science, Scopus, Bireme/MedLine, and SciELO online databases were conducted for articles reporting the effects of CrossFit training. The systematic review followed the PRISMA guidelines. The Oxford Levels of Evidence was used for all included articles, and only studies that investigated the effects of CrossFit as a training program were included in the meta-analysis. For the meta-analysis, effect sizes (ESs) with 95% confidence interval (CI) were calculated and heterogeneity was assessed using a random-effects model. Thirty-one articles were included in the systematic review and four were included in the meta-analysis. However, only two studies had a high level of evidence at low risk of bias. Scientific literature related to CrossFit has reported on body composition, psycho-physiological parameters, musculoskeletal injury risk, life and health aspects, and psycho-social behavior. In the meta-analysis, significant results were not found for any variables. The current scientific literature related to CrossFit has few studies with high level of evidence at low risk of bias. However, preliminary data has suggested that CrossFit practice is associated with higher levels of sense of community, satisfaction, and motivation.

Meta-analysis of expression and function of neprilysin in Alzheimer's disease.

Science.gov (United States)

Zhang, Huifeng; Liu, Dan; Wang, Yixing; Huang, Huanhuan; Zhao, Yujia; Zhou, Hui

2017-09-14

Neprilysin (NEP) is one of the most important Aβ-degrading enzymes, and its expression and activity in Alzheimer's brain have been widely reported, but the results remain debatable. Thus, the meta-analysis was performed to elucidate the role of NEP in Alzheimer's disease (AD). The relevant case-control or cohort studies were retrieved according to our inclusion/exclusion criteria. Six studies with 123 controls and 141 AD cases, seven studies with 102 controls and 90 AD cases, and four studies with 93 controls and 132 AD cases were included in meta-analysis of NEP's protein, mRNA, and enzyme activity respectively. We conducted Meta regression to detect the sources of heterogeneity and further performed cumulative meta-analysis or subgroup analysis. Our meta-analysis revealed a significantly lower level of NEP mRNA (SMD=-0.44, 95%CI: -0.87, -0.00, p=0.049) in AD cases than in non-AD cases, and such pattern was not altered over time in the cumulative meta-analysis. However, the decrease of NEP protein (SMD=-0.18, 95%CI: -0.62, 0.25) and enzyme activity (SMD=-0.35, 95%CI: -1.03, 0.32) in AD cases did not pass the significance check, while the cumulative meta-analysis by average age showed the pooled effect became insignificant as adding the studies with younger subjects, which indicates that the protein expression and enzyme activity of NEP in the cortex are affected by age. Therefore, the present meta-analysis suggests the need of further investigation of roles of NEP in AD pathogenesis and treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

Meta-analysis in a nutshell: Techniques and general findings

DEFF Research Database (Denmark)

Paldam, Martin

2015-01-01

The purpose of this article is to introduce the technique and main findings of meta-analysis to the reader, who is unfamiliar with the field and has the usual objections. A meta-analysis is a quantitative survey of a literature reporting estimates of the same parameter. The funnel showing...

Serum tumor-associated autoantibodies as diagnostic biomarkers for lung cancer: A systematic review and meta-analysis.

Directory of Open Access Journals (Sweden)

Zhen-Ming Tang

Full Text Available We performed a comprehensive review and meta-analysis to evaluate the diagnostic values of serum single and multiplex tumor-associated autoantibodies (TAAbs in patients with lung cancer (LC.We searched the MEDLINE and EMBASE databases for relevant studies investigating serum TAAbs for the diagnosis of LC. The primary outcomes included sensitivity, specificity and accuracy of the test.The systematic review and meta-analysis included 31 articles with single autoantibody and 39 with multiplex autoantibodies. Enzyme-linked immunosorbent assay (ELISA was the most common detection method. For the diagnosis of patients with all stages and early-stage LC, different single or combinations of TAAbs demonstrated different diagnostic values. Although individual TAAbs showed low diagnostic sensitivity, the combination of multiplex autoantibodies offered relatively high sensitivity. For the meta-analysis of a same panel of autoantibodies in patients at all stages of LC, the pooled results of the panel of 6 TAAbs (p53, NY-ESO-1, CAGE, GBU4-5, Annexin 1 and SOX2 were: sensitivity 38% (95% CI 0.35-0.40, specificity 89% (95% CI 0.86-0.91, diagnostic accuracy 65.9% (range 62.5-81.8%, AUC 0.52 (0.48-0.57, while the summary estimates of 7 TAAbs (p53, CAGE, NY-ESO-1, GBU4-5, SOX2, MAGE A4 and Hu-D were: sensitivity 47% (95% CI 0.34-0.60, specificity 90% (95% CI 0.89-0.92, diagnostic accuracy 78.4% (range 67.5-88.8%, AUC 0.90 (0.87-0.93. For the meta-analysis of the same panel of autoantibodies in patients at early-stage of LC, the sensitivities of both panels of 7 TAAbs and 6 TAAbs were 40% and 29.7%, while their specificities were 91% and 87%, respectively.Serum single or combinations of multiplex autoantibodies can be used as a tool for the diagnosis of LC patients at all stages or early-stage, but the combination of multiplex autoantibodies shows a higher detection capacity; the diagnostic value of the panel of 7 TAAbs is higher than the panel of 6 TAAbs, which

Adoptive immunotherapy with interleukin-2 & induced killer cells in non-small cell lung cancer: A systematic review & meta-analysis

Directory of Open Access Journals (Sweden)

Denghai Mi

2016-01-01

Interpretation & conclusions: The meta-analysis showed that IL-2 or induced killer cells combination therapy was efficacious in treating NSCLC and improved overall survival. Further analysis of trials having adequate information and data need to be done to confirm these findings.

Does chocolate reduce blood pressure? A meta-analysis

Directory of Open Access Journals (Sweden)

Ried Karin

2010-06-01

Full Text Available Abstract Background Dark chocolate and flavanol-rich cocoa products have attracted interest as an alternative treatment option for hypertension, a known risk factor for cardiovascular disease. Previous meta-analyses concluded that cocoa-rich foods may reduce blood pressure. Recently, several additional trials have been conducted with conflicting results. Our study summarises current evidence on the effect of flavanol-rich cocoa products on blood pressure in hypertensive and normotensive individuals. Methods We searched Medline, Cochrane and international trial registries between 1955 and 2009 for randomised controlled trials investigating the effect of cocoa as food or drink compared with placebo on systolic and diastolic blood pressure (SBP/DBP for a minimum duration of 2 weeks. We conducted random effects meta-analysis of all studies fitting the inclusion criteria, as well as subgroup analysis by baseline blood pressure (hypertensive/normotensive. Meta-regression analysis explored the association between type of treatment, dosage, duration or baseline blood pressure and blood pressure outcome. Statistical significance was set at P Results Fifteen trial arms of 13 assessed studies met the inclusion criteria. Pooled meta-analysis of all trials revealed a significant blood pressure-reducing effect of cocoa-chocolate compared with control (mean BP change ± SE: SBP: -3.2 ± 1.9 mmHg, P = 0.001; DBP: -2.0 ± 1.3 mmHg, P = 0.003. However, subgroup meta-analysis was significant only for the hypertensive or prehypertensive subgroups (SBP: -5.0 ± 3.0 mmHg; P = 0.0009; DBP: -2.7 ± 2.2 mm Hg, P = 0.01, while BP was not significantly reduced in the normotensive subgroups (SBP: -1.6 ± 2.3 mmHg, P = 0.17; DBP: -1.3 ± 1.6 mmHg, P = 0.12. Nine trials used chocolate containing 50% to 70% cocoa compared with white chocolate or other cocoa-free controls, while six trials compared high- with low-flavanol cocoa products. Daily flavanol dosages ranged from 30

Meta-analysis in epidemiology | Yach | South African Medical Journal

African Journals Online (AJOL)

Meta-analysis is the structured and systematic qualitative and quantitative integration of the results of several independent studies (Le. the epidemiology of results). As in any epidemiological study, a meta-analysis needs to start with clearly stated aims and objectives. Attention needs to be paid to selection bias in selecting ...

Individual Participant Data Meta-Analysis of Mechanical Workplace Risk Factors and Low Back Pain

Science.gov (United States)

Shannon, Harry S.; Wells, Richard P.; Walter, Stephen D.; Cole, Donald C.; Côté, Pierre; Frank, John; Hogg-Johnson, Sheilah; Langlois, Lacey E.

2012-01-01

Objectives. We used individual participant data from multiple studies to conduct a comprehensive meta-analysis of mechanical exposures in the workplace and low back pain. Methods. We conducted a systematic literature search and contacted an author of each study to request their individual participant data. Because outcome definitions and exposure measures were not uniform across studies, we conducted 2 substudies: (1) to identify sets of outcome definitions that could be combined in a meta-analysis and (2) to develop methods to translate mechanical exposure onto a common metric. We used generalized estimating equation regression to analyze the data. Results. The odds ratios (ORs) for posture exposures ranged from 1.1 to 2.0. Force exposure ORs ranged from 1.4 to 2.1. The magnitudes of the ORs differed according to the definition of low back pain, and heterogeneity was associated with both study-level and individual-level characteristics. Conclusions. We found small to moderate ORs for the association of mechanical exposures and low back pain, although the relationships were complex. The presence of individual-level OR modifiers in such an area can be best understood by conducting a meta-analysis of individual participant data. PMID:22390445

Medicinal plants with promising antileishmanial activity in Iran: a systematic review and meta-analysis

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Masoud Soosaraei

2017-09-01

Conclusion: The most Iranian plants used as anti-leishmanial activity were Artemisia species, Allium sativum, Achilleamille folium, Peganum harmala and Thymus vulgaris. The present systematic and meta-analysis review provide valuable information about natural products with anti-Leishmania activity, which would be examined in the future experimental and clinical trials and herbal combination therapy.

Prognostic factors associated with the success rates of posterior orthodontic miniscrew implants: A subgroup meta-analysis.

Science.gov (United States)

Hong, Sung-Bin; Kusnoto, Budi; Kim, Eun-Jeong; BeGole, Ellen A; Hwang, Hyeon-Shik; Lim, Hoi-Jeong

2016-03-01

To systematically review previous studies and to assess, via a subgroup meta-analysis, the combined odds ratio (OR) of prognostic factors affecting the success of miniscrew implants (MIs) inserted into the buccal posterior region. Three electronic searches that were limited to articles on clinical human studies using MIs that were published in English prior to March 2015 were conducted. The outcome measure was the success of MIs. Patient factors included age, sex, and jaw of insertion (maxilla vs. mandible), while the MI factors included length and diameter. A meta-analysis was performed on 17 individual studies. The quality of each study was assessed for non-randomized studies and quantified using the Newcastle-Ottawa Scale. The meta-analysis outcome was a combined OR. Subgroup and sensitivity analyses based on the study design, study quality, and sample size of miniscrews implanted were performed. Significantly higher success rates were revealed for MIs inserted in the maxilla, for patients ≥ 20 years of age, and for long MIs (≥ 8 mm) and MIs with a large diameter (> 1.4 mm). All subgroups acquired homogeneity, and the combined OR of the prospective studies (OR, 3.67; 95% confidence interval [CI], 2.10-6.44) was significantly higher in the maxilla than that in the retrospective studies (OR, 2.10; 95% CI, 1.60-2.74). When a treatment plan is made, these risk factors, i.e. jaw of insertion, age, MI length, and MI diameter, should be taken into account, while sex is not critical to the success of MIs.

Meta-analysis of effects of gender in combination with carcass weight and breed on pork quality.

Science.gov (United States)

Trefan, L; Doeschl-Wilson, A; Rooke, J A; Terlouw, C; Bünger, L

2013-03-01

Meta-analysis was performed to quantify the effects of gender in combination with carcass weight and breed on pork quality. Altogether published results from 43 references were used. The traits analyzed were pH at 45 min (pH45min) and pH at 24 h (pH24hr) postmortem, objective color attributes lightness (L*), redness (a*), and yellowness (b*; CIE color system), color and marbling scores, drip loss, intramuscular fat content (IMF), and backfat thickness (P2), as well as sensory scores of juiciness and tenderness. Data for 2 muscle types, LM and Musculus semimembranosus (SMM), were used for the analysis. Swine genders were defined as intact/entire male (EM), surgically castrated male (SM), immunocastrated male (IM), and entire female (EF). After standardization of scaled traits (color, marbling scores, juiciness, tenderness) and accounting for cold carcass weight (CW), statistical analysis was performed using mixed models where breed was included as random effect. The analysis found a general effect of gender on each trait and multiple comparisons identified significant differences among the individual genders for L* (lightness), marbling scores, IMF, P2 in LM, and pH24hr in SMM. For these traits, when genders were grouped into gender categories as "castrates" (IM, SM) and "natural genders" (EM, EF), significant differences were found among estimates related to these categories. Furthermore, significant differences were found between castrates and individual gender types, indicating that castrated animals statistically segregated regarding their pork quality and regardless of type of castration. Pork of SM/EM animals has been found to be the fattest/leanest and there is indication that IM pork has the lightest meat color. Carcass weight dependence was found to be nonlinear (quadratic) for a*, P2, and marbling scores, and linear for b* and color scores in LM and pH24hr in SMM. The analysis identified significant breed effects for all traits, with large variation in the

Efficacy of and patient compliance with a ketogenic diet in adults with intractable epilepsy: a meta-analysis.

Science.gov (United States)

Ye, Fang; Li, Xiao-Jia; Jiang, Wan-Lin; Sun, Hong-Bin; Liu, Jie

2015-01-01

Despite the successful use of a ketogenic diet in pediatric epilepsy, its application in adults has been limited. The aim of this meta-analysis was to summarize the findings of relevant published studies in order to identify the efficacy of and compliance with a ketogenic diet and its main subtypes (i.e., classic ketogenic diet and modified Atkins diet) in adults with intractable epilepsy, and to provide useful information for clinical practice. Electronic searches of PubMed, EMBASE, Google Scholar, and the ISI Web of Science were conducted to identify studies of the efficacy of and patient compliance with a ketogenic diet in adults with intractable epilepsy; the included studies were reviewed. Meta-analyses were performed using STATA to determine combined efficacy rates and combined rates of compliance with the ketogenic diet and its main subtypes. In total, 12 studies qualified for inclusion, and data from 270 patients were evaluated.The results of the meta-analysis revealed combined efficacy rates of all types of ketogenic diet, a classical ketogenic diet, and a modified Atkins diet were 42%, 52%, and 34%, respectively; the corresponding combined compliance rates were 45%, 38%, and 56%. The results indicate that a ketogenic diet is a promising complementary therapy in adult intractable epilepsy, and that while a classical ketogenic diet may be more effective, adult patients are likely to be less compliant with it than with a modified Atkins diet.

Social relationships and cognitive decline: a systematic review and meta-analysis of longitudinal cohort studies.

Science.gov (United States)

Kuiper, Jisca S; Zuidersma, Marij; Zuidema, Sytse U; Burgerhof, Johannes Gm; Stolk, Ronald P; Oude Voshaar, Richard C; Smidt, Nynke

2016-08-01

Although poor social relationships are assumed to contribute to cognitive decline, meta-analytic approaches have not been applied. Individual study results are mixed and difficult to interpret due to heterogeneity in measures of social relationships. We conducted a systematic review and meta-analysis to investigate the relation between poor social relationships and cognitive decline. MEDLINE, Embase and PsycINFO were searched for longitudinal cohort studies examining various aspects of social relationships and cognitive decline in the general population. Odds ratios (ORs) with 95% confidence intervals (CIs) were pooled using random effects meta-analysis. Sources of heterogeneity were explored and likelihood of publication bias was assessed. We stratified analyses according to three aspects of social relationships: structural, functional and a combination of these. We identified 43 articles. Poor social relationships predicted cognitive decline; for structural (19 studies): pooled OR: 1.08 (95% CI: 1.05-1.11); functional (8 studies): pooled OR: 1.15 (95% CI: 1.00-1.32); and combined measures (7 studies): pooled OR: 1.12 (95% CI: 1.01-1.24). Meta-regression and subgroup analyses showed that the heterogeneity could be explained by the type of social relationship measurement and methodological quality of included studies. Despite heterogeneity in study design and measures, our meta-analyses show that multiple aspects of social relationships are associated with cognitive decline. As evidence for publication bias was found, the association might be overestimated and should therefore be interpreted with caution. Future studies are needed to better define the mechanisms underlying these associations. Potential causality of this prognostic association should be examined in future randomized controlled studies. © The Author 2016; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

Quick, “Imputation-free” meta-analysis with proxy-SNPs

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Meesters Christian

2012-09-01

Full Text Available Abstract Background Meta-analysis (MA is widely used to pool genome-wide association studies (GWASes in order to a increase the power to detect strong or weak genotype effects or b as a result verification method. As a consequence of differing SNP panels among genotyping chips, imputation is the method of choice within GWAS consortia to avoid losing too many SNPs in a MA. YAMAS (Yet Another Meta Analysis Software, however, enables cross-GWAS conclusions prior to finished and polished imputation runs, which eventually are time-consuming. Results Here we present a fast method to avoid forfeiting SNPs present in only a subset of studies, without relying on imputation. This is accomplished by using reference linkage disequilibrium data from 1,000 Genomes/HapMap projects to find proxy-SNPs together with in-phase alleles for SNPs missing in at least one study. MA is conducted by combining association effect estimates of a SNP and those of its proxy-SNPs. Our algorithm is implemented in the MA software YAMAS. Association results from GWAS analysis applications can be used as input files for MA, tremendously speeding up MA compared to the conventional imputation approach. We show that our proxy algorithm is well-powered and yields valuable ad hoc results, possibly providing an incentive for follow-up studies. We propose our method as a quick screening step prior to imputation-based MA, as well as an additional main approach for studies without available reference data matching the ethnicities of study participants. As a proof of principle, we analyzed six dbGaP Type II Diabetes GWAS and found that the proxy algorithm clearly outperforms naïve MA on the p-value level: for 17 out of 23 we observe an improvement on the p-value level by a factor of more than two, and a maximum improvement by a factor of 2127. Conclusions YAMAS is an efficient and fast meta-analysis program which offers various methods, including conventional MA as well as inserting proxy

[Effectiveness of acupuncture in postoperative ileus: a systematic review and Meta-analysis].

Science.gov (United States)

Cheong, Kah Bik; Zhang, Jiping; Huang, Yong

2016-06-01

To conduct a systematic review and Meta-analysis of the effectiveness of acupuncture and common acupoint selection for postoperative ileus (POI). Randomized controlled trials (RCTs) comparing acupuncture and non-acupuncture treatment were identified from the databases PubMed, Cochrane, EBSCO (Academic Source Premier and MEDLINE), Ovid (including Evidence-Based Medicine Reviews), China National Knowledge Infrastructure, and Wanfang Data. The data from eligible studies were extracted and a Meta-analysis performed using a fixed-effects model. Results were expressed as relative risk (RR) for dichotomous data, and 95% CI (confidence intervals) were calculated. Each trial was evaluated using the CONSORT (Consolidated Standards of Reporting Trials) and STRICTA (STandards for Reporting Interventions in Controlled Trials of Acupuncture) guideline . The quality of the study was assessed using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. Of the 69 studies screened, eight RCTs were included for review. Among these, four RCTs (with a total of 123 patients in the intervention groups and 124 patients in the control groups) met the criteria for Meta-analysis. The Meta-analysis results indicated that acupuncture combined with usual care showed a significantly higher total effective rate than the control condition (usual care) (RR 1.09, 95% CI 1.01, 1.18; P = 0.02). Zusanli (ST 36) and Shangjuxu (ST 37) were the most common acupoints selected. However, the quality of the studies was generally low, as they did not emphasize the use of blinding. The results suggested that acupuncture might be effective in improving POI; however, a definite conclusion could not be drawn because of the low quality of trials. Further large-scale, high-quality randomized clinical trials are needed to validate these findings and to develop a standardized method of treatment. We hope that the present results will lead to improved research, resulting in better

Traumatic stress and accelerated DNA methylation age: A meta-analysis.

Science.gov (United States)

Wolf, Erika J; Maniates, Hannah; Nugent, Nicole; Maihofer, Adam X; Armstrong, Don; Ratanatharathorn, Andrew; Ashley-Koch, Allison E; Garrett, Melanie; Kimbrel, Nathan A; Lori, Adriana; Va Mid-Atlantic Mirecc Workgroup; Aiello, Allison E; Baker, Dewleen G; Beckham, Jean C; Boks, Marco P; Galea, Sandro; Geuze, Elbert; Hauser, Michael A; Kessler, Ronald C; Koenen, Karestan C; Miller, Mark W; Ressler, Kerry J; Risbrough, Victoria; Rutten, Bart P F; Stein, Murray B; Ursano, Robert J; Vermetten, Eric; Vinkers, Christiaan H; Uddin, Monica; Smith, Alicia K; Nievergelt, Caroline M; Logue, Mark W

2018-06-01

Recent studies examining the association between posttraumatic stress disorder (PTSD) and accelerated aging, as defined by DNA methylation-based estimates of cellular age that exceed chronological age, have yielded mixed results. We conducted a meta-analysis of trauma exposure and PTSD diagnosis and symptom severity in association with accelerated DNA methylation age using data from 9 cohorts contributing to the Psychiatric Genomics Consortium PTSD Epigenetics Workgroup (combined N = 2186). Associations between demographic and cellular variables and accelerated DNA methylation age were also examined, as was the moderating influence of demographic variables. Meta-analysis of regression coefficients from contributing cohorts revealed that childhood trauma exposure (when measured with the Childhood Trauma Questionnaire) and lifetime PTSD severity evidenced significant, albeit small, meta-analytic associations with accelerated DNA methylation age (ps = 0.028 and 0.016, respectively). Sex, CD4T cell proportions, and natural killer cell proportions were also significantly associated with accelerated DNA methylation age (all ps age. There was no evidence of moderation of the trauma or PTSD variables by demographic factors. Results suggest that traumatic stress is associated with advanced epigenetic age and raise the possibility that cells integral to immune system maintenance and responsivity play a role in this. This study highlights the need for additional research into the biological mechanisms linking traumatic stress to accelerated DNA methylation age and the importance of furthering our understanding of the neurobiological and health consequences of PTSD. Published by Elsevier Ltd.

Meta-analytic framework for liquid association.

Science.gov (United States)

Wang, Lin; Liu, Silvia; Ding, Ying; Yuan, Shin-Sheng; Ho, Yen-Yi; Tseng, George C

2017-07-15

Although coexpression analysis via pair-wise expression correlation is popularly used to elucidate gene-gene interactions at the whole-genome scale, many complicated multi-gene regulations require more advanced detection methods. Liquid association (LA) is a powerful tool to detect the dynamic correlation of two gene variables depending on the expression level of a third variable (LA scouting gene). LA detection from single transcriptomic study, however, is often unstable and not generalizable due to cohort bias, biological variation and limited sample size. With the rapid development of microarray and NGS technology, LA analysis combining multiple gene expression studies can provide more accurate and stable results. In this article, we proposed two meta-analytic approaches for LA analysis (MetaLA and MetaMLA) to combine multiple transcriptomic studies. To compensate demanding computing, we also proposed a two-step fast screening algorithm for more efficient genome-wide screening: bootstrap filtering and sign filtering. We applied the methods to five Saccharomyces cerevisiae datasets related to environmental changes. The fast screening algorithm reduced 98% of running time. When compared with single study analysis, MetaLA and MetaMLA provided stronger detection signal and more consistent and stable results. The top triplets are highly enriched in fundamental biological processes related to environmental changes. Our method can help biologists understand underlying regulatory mechanisms under different environmental exposure or disease states. A MetaLA R package, data and code for this article are available at http://tsenglab.biostat.pitt.edu/software.htm. ctseng@pitt.edu. Supplementary data are available at Bioinformatics online. © The Author (2017). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Meta-analysis on the efficacy of foot-and-mouth disease emergency vaccination

DEFF Research Database (Denmark)

Hisham Beshara Halasa, Tariq; Boklund, Anette; Cox, S.

2012-01-01

The objectives of this study were to provide a summary quantification of the efficacy of FMD emergency vaccination based on a systematic review and a meta-analysis of available literature, and to further discuss the suitability of this review and meta-analysis to summarize and further interpret...... of clinical signs including FMD lesions and fever, while the virological protection parameter was estimated based on the outcome of laboratory tests that were used to diagnose FMD infection. A meta-analysis relative risk was calculated per protection parameter. Results of the meta-analyses were examined using...... vaccine. Fortunately, no significant bias that would alter the conclusions was encountered in the analysis. Meta-analysis showed to be a useful tool to summarize literature results from a systematic review of the efficacy of foot and mouth disease emergency vaccination....

Prognostic factors in pediatric pulmonary arterial hypertension: A systematic review and meta-analysis.

Science.gov (United States)

Ploegstra, Mark-Jan; Zijlstra, Willemijn M H; Douwes, Johannes M; Hillege, Hans L; Berger, Rolf M F

2015-04-01

Despite the introduction of targeted therapies in pediatric pulmonary arterial hypertension (PAH), prognosis remains poor. For the definition of treatment strategies and guidelines, there is a high need for an evidence-based recapitulation of prognostic factors. The aim of this study was to identify and evaluate prognostic factors in pediatric PAH by a systematic review of the literature and to summarize the prognostic value of currently reported prognostic factors using meta-analysis. Medline, EMBASE and Cochrane Library were searched on April 1st 2014 to identify original studies that described predictors of mortality or lung-transplantation exclusively in children with PAH. 1053 citations were identified, of which 25 were included for further analysis. Hazard ratios (HR) and 95% confidence intervals were extracted from the papers. For variables studied in at least three non-overlapping cohorts, a combined HR was calculated using random-effects meta-analysis. WHO functional class (WHO-FC, HR 2.7), (N-terminal pro-) brain natriuretic peptide ([NT-pro]BNP, HR 3.2), mean right atrial pressure (mRAP, HR 1.1), cardiac index (HR 0.7), indexed pulmonary vascular resistance (PVRi, HR 1.3) and acute vasodilator response (HR 0.3) were identified as significant prognostic factors (p ≤ 0.001). This systematic review combined with separate meta-analyses shows that WHO-FC, (NT-pro)BNP, mRAP, PVRi, cardiac index and acute vasodilator response are consistently reported prognostic factors for outcome in pediatric PAH. These variables are useful clinical tools to assess prognosis and should be incorporated in treatment strategies and guidelines for children with PAH. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Effect of dietary fiber on circulating C-reactive protein in overweight and obese adults: a meta-analysis of randomized controlled trials.

Science.gov (United States)

Jiao, Jun; Xu, Jia-Ying; Zhang, Weiguo; Han, Shufen; Qin, Li-Qiang

2015-02-01

Previous studies suggested that dietary fiber intake may have a lowing effect on circulating C-reactive protein (CRP) level, a sensitive marker of inflammation, in overweight/obese adults with inconsistent results. A literature search was performed in April 2014 for related randomized controlled trials (RCTs) and meta-analysis was conducted. Meta-analysis including 14 RCTs showed that intervention with dietary fiber or fiber-rich food, compared with control, produced a slight, but significant reduction of 0.37 mg/L (95% CI -0.74, 0) in circulating CRP level among this population. Subgroup analyses showed that such a significant reduction was only observed after combining studies where the total fiber intake was 8 g/d higher in the intervention group than in the control group. No obvious heterogeneity and publication bias were found in the meta-analysis. In conclusion, this meta-analysis provides evidence that dietary fiber or food naturally rich in fiber has beneficial effects on circulating CRP level in overweight/obese adults.

The role of solifenacin, as monotherapy or combination with tamsulosin in ureteral stent-related symptoms: a systematic review and meta-analysis.

Science.gov (United States)

Wang, Jue; Zhang, Xiaobei; Zhang, Tiande; Mu, Jianjun; Bai, Bing; Lei, Yi

2017-11-01

Ureteral stenting is associated with various morbidity and reduced quality of life. We systematically evaluated the efficacy and safety of solifenacin as monotherapy, or combined therapy with tamsulosin versus control or tamsulosin monotherapy in stent-related symptoms (SRSs). Randomized controlled trials evaluating solifenacin or its combination with tamsulosin for the treatment of SRSs were identified via a comprehensive search of Pubmed, Embase, Ovid, The Cochrane Library and relevant sources up to February 2017. Ureteral stent symptom questionnaire (USSQ) and drug-related complications were pooled for meta-analysis. Mean difference and risk difference were calculated as appropriate for each outcome to determine the cumulative effect size. There were 10 studies involving 1786 participants finally eligible in the quantitative analysis. Solifenacin monotherapy significantly reduced the total score of USSQ [MD -14.90; 95% CI (-25.19, -4.60); P = 0.005], as well as indexes of urinary symptoms, body pain, general health, sexual performance, and hematuria (P = 0.02, P = 0.009, P = 0.004, P = 0.02, P = 0.02, respectively), but the differences were insignificant when compared with tamsulosin except improved sexual performance (P = 0.004). Combined therapy of solifenacin and tamsulosin showed no beneficial effects in all indexes of USSQ over solifenacin monotherapy. Only slightly higher incidence of dry mouth (P = 0.02) was found with solifenacin versus control. The result demonstrates the safety and efficacy of solifenacin in reducing SRSs, but no significant advantage was found over tamsulosin. In addition, combination of solifenacin and tamsulosin did not show beneficial effects over solifenacin monotherapy. More high quality trials are warranted to further address this issue, however.

Global Prevalence of Elder Abuse: A Meta-analysis and Meta-regression.

Science.gov (United States)

Ho, C Sh; Wong, S Y; Chiu, M M; Ho, R Cm

2017-06-01

Elder abuse is increasingly recognised as a global public health and social problem. There has been limited inter-study comparison of the prevalence and risk factors for elder abuse. This study aimed to estimate the pooled and subtype prevalence of elder abuse worldwide and identify significant associated risk factors. We conducted a meta-analysis and meta-regression of 34 population-based and 17 non-population-based studies. The pooled prevalences of elder abuse were 10.0% (95% confidence interval, 5.2%-18.6%) and 34.3% (95% confidence interval, 22.9%-47.8%) in population-based studies and third party- or caregiver-reported studies, respectively. Being in a marital relationship was found to be a significant moderator using random-effects model. This meta-analysis revealed that third parties or caregivers were more likely to report abuse than older abused adults. Subgroup analyses showed that females and those resident in non-western countries were more likely to be abused. Emotional abuse was the most prevalent elder abuse subtype and financial abuse was less commonly reported by third parties or caregivers. Heterogeneity in the prevalence was due to the high proportion of married older adults in the sample. Subgroup analysis showed that cultural factors, subtypes of abuse, and gender also contributed to heterogeneity in the pooled prevalence of elder abuse.

The relationship between job satisfaction and health: a meta-analysis.

Science.gov (United States)

Faragher, E B; Cass, M; Cooper, C L

2005-02-01

A vast number of published studies have suggested a link between job satisfaction levels and health. The sizes of the relationships reported vary widely. Narrative overviews of this relationship have been published, but no systematic meta-analysis review has been conducted. A systematic review and meta-analysis of 485 studies with a combined sample size of 267 995 individuals was conducted, evaluating the research evidence linking self-report measures of job satisfaction to measures of physical and mental wellbeing. The overall correlation combined across all health measures was r = 0.312 (0.370 after Schmidt-Hunter adjustment). Job satisfaction was most strongly associated with mental/psychological problems; strongest relationships were found for burnout (corrected r = 0.478), self-esteem(r = 0.429), depression (r = 0.428), and anxiety(r = 0.420). The correlation with subjective physical illness was more modest (r = 0.287). Correlations in excess of 0.3 are rare in this context. The relationships found suggest that job satisfaction level is an important factor influencing the health of workers. Organisations should include the development of stress management policies to identify and eradicate work practices that cause most job dissatisfaction as part of any exercise aimed at improving employee health. Occupational health clinicians should consider counselling employees diagnosed as having psychological problems to critically evaluate their work-and help them to explore ways of gaining greater satisfaction from this important aspect of their life.

Meta-Analysis of the Reasoned Action Approach (RAA) to Understanding Health Behaviors.

Science.gov (United States)

McEachan, Rosemary; Taylor, Natalie; Harrison, Reema; Lawton, Rebecca; Gardner, Peter; Conner, Mark

2016-08-01

Reasoned action approach (RAA) includes subcomponents of attitude (experiential/instrumental), perceived norm (injunctive/descriptive), and perceived behavioral control (capacity/autonomy) to predict intention and behavior. To provide a meta-analysis of the RAA for health behaviors focusing on comparing the pairs of RAA subcomponents and differences between health protection and health-risk behaviors. The present research reports a meta-analysis of correlational tests of RAA subcomponents, examination of moderators, and combined effects of subcomponents on intention and behavior. Regressions were used to predict intention and behavior based on data from studies measuring all variables. Capacity and experiential attitude had large, and other constructs had small-medium-sized correlations with intention; all constructs except autonomy were significant independent predictors of intention in regressions. Intention, capacity, and experiential attitude had medium-large, and other constructs had small-medium-sized correlations with behavior; intention, capacity, experiential attitude, and descriptive norm were significant independent predictors of behavior in regressions. The RAA subcomponents have utility in predicting and understanding health behaviors.

Psychotherapy for chronic major depression and dysthymia: A meta analysis.

NARCIS (Netherlands)

Cuijpers, P.; Straten, van A.; Schuurmans, J.; Oppen, van P.C.; Hollon, S.D.; Andersson, G.

2009-01-01

Abstract Although several studies have examined the effects of psychotherapy on chronic depression and dysthymia, no meta-analysis has been conducted to integrate results of these studies. We conducted a meta-analysis of 16 randomized trials examining the effects of psychotherapy on chronic

Meta-Analysis for Sociology – A Measure-Driven Approach

Science.gov (United States)

Roelfs, David J.; Shor, Eran; Falzon, Louise; Davidson, Karina W.; Schwartz, Joseph E.

2013-01-01

Meta-analytic methods are becoming increasingly important in sociological research. In this article we present an approach for meta-analysis which is especially helpful for sociologists. Conventional approaches to meta-analysis often prioritize “concept-driven” literature searches. However, in disciplines with high theoretical diversity, such as sociology, this search approach might constrain the researcher’s ability to fully exploit the entire body of relevant work. We explicate a “measure-driven” approach, in which iterative searches and new computerized search techniques are used to increase the range of publications found (and thus the range of possible analyses) and to traverse time and disciplinary boundaries. We demonstrate this measure-driven search approach with two meta-analytic projects, examining the effects of various social variables on all-cause mortality. PMID:24163498

Role of the Fc gamma receptor IIA polymorphism in the antiphospholipid syndrome - an international meta-analysis

NARCIS (Netherlands)

Karassa, FB; Bijl, M; Davies, KA; Kallenberg, CGM; Khamashta, MA; Manger, K; Michel, M; Piette, JC; Salmon, JE; Song, YW; Tsuchiya, N; Yoo, DH; Ioannidis, JPA

Objective. To assess the impact of the FcgammaRIIA-R/H131 polymorphism on the risk for antiphospholipid syndrome (APS), both primary and secondary to systemic lupus erythematosus (SLE). Methods. This international meta-analysis combined data from 9 research teams. FcgammaRIIA-R/H131 genotypes were

The combined effects of meta-stereotypes and audience on outgroup and ingroup helping

NARCIS (Netherlands)

van Leeuwen, E.; Oostenbrink, J.J.; Twilt, A.

2014-01-01

Salient meta-stereotypes can promote outgroup helping in a way that allows an ingroup to make a good impression. Although the presence of an audience can similarly activate impression-management concerns, their combined effects on intergroup helping have never been investigated, which was the goal

Thirty Years of Evidence on the Efficacy of Drug Treatments for Chronic Heart Failure With Reduced Ejection Fraction: A Network Meta-Analysis.

Science.gov (United States)

Burnett, Heather; Earley, Amy; Voors, Adriaan A; Senni, Michele; McMurray, John J V; Deschaseaux, Celine; Cope, Shannon

2017-01-01

Treatments that reduce mortality and morbidity in patients with heart failure with reduced ejection fraction, including angiotensin-converting enzyme inhibitors (ACEI), angiotensin receptor blockers (ARB), β-blockers (BB), mineralocorticoid receptor antagonists (MRA), and angiotensin receptor-neprilysin inhibitors (ARNI), have not been studied in a head-to-head fashion. This network meta-analysis aimed to compare the efficacy of these drugs and their combinations regarding all-cause mortality in patients with heart failure with reduced ejection fraction. A systematic literature review identified 57 randomized controlled trials published between 1987 and 2015, which were compared in terms of study and patient characteristics, baseline risk, outcome definitions, and the observed treatment effects. Despite differences identified in terms of study duration, New York Heart Association class, ejection fraction, and use of background digoxin, a network meta-analysis was considered feasible and all trials were analyzed simultaneously. The random-effects network meta-analysis suggested that the combination of ACEI+BB+MRA was associated with a 56% reduction in mortality versus placebo (hazard ratio 0.44, 95% credible interval 0.26-0.66); ARNI+BB+MRA was associated with the greatest reduction in all-cause mortality versus placebo (hazard ratio 0.37, 95% credible interval 0.19-0.65). A sensitivity analysis that did not account for background therapy suggested that ARNI monotherapy is more efficacious than ACEI or ARB monotherapy. The network meta-analysis showed that treatment with ACEI, ARB, BB, MRA, and ARNI and their combinations were better than the treatment with placebo in reducing all-cause mortality, with the exception of ARB monotherapy and ARB plus ACEI. The combination of ARNI+BB+MRA resulted in the greatest mortality reduction. © 2017 The Authors.

Simpson's paradox visualized: The example of the Rosiglitazone meta-analysis

Directory of Open Access Journals (Sweden)

Schumacher Martin

2008-05-01

Full Text Available Abstract Background Simpson's paradox is sometimes referred to in the areas of epidemiology and clinical research. It can also be found in meta-analysis of randomized clinical trials. However, though readers are able to recalculate examples from hypothetical as well as real data, they may have problems to easily figure where it emerges from. Method First, two kinds of plots are proposed to illustrate the phenomenon graphically, a scatter plot and a line graph. Subsequently, these can be overlaid, resulting in a overlay plot. The plots are applied to the recent large meta-analysis of adverse effects of rosiglitazone on myocardial infarction and to an example from the literature. A large set of meta-analyses is screened for further examples. Results As noted earlier by others, occurrence of Simpson's paradox in the meta-analytic setting, if present, is associated with imbalance of treatment arm size. This is well illustrated by the proposed plots. The rosiglitazone meta-analysis shows an effect reversion if all trials are pooled. In a sample of 157 meta-analyses, nine showed an effect reversion after pooling, though non-significant in all cases. Conclusion The plots give insight on how the imbalance of trial arm size works as a confounder, thus producing Simpson's paradox. Readers can see why meta-analytic methods must be used and what is wrong with simple pooling.

Combined oral contraceptives and/or antiandrogens versus insulin sensitizers for polycystic ovary syndrome: a systematic review and meta-analysis.

Science.gov (United States)

Luque-Ramírez, Manuel; Nattero-Chávez, Lía; Ortiz Flores, Andrés E; Escobar-Morreale, Héctor F

2017-12-27

Androgen excess is a key pathogenetic mechanism in polycystic ovary syndrome (PCOS), although hyperinsulinism also contributes to androgen secretion. Therapeutic approaches for adult patients not seeking fertility include combined oral contraceptives (COC), antiandrogens (AA) and/or insulin sensitizers, although these practices are supported by limited high-quality evidence. We aimed to assess the efficacy and safety of these common treatments for PCOS by conducting a meta-analysis of RCTs with the following review questions: Which is the more appropriate therapeutic approach for hyperandrogenic symptoms, hyperandrogenemia, and ovulatory dysfunction in adult women with PCOS not seeking fertility; What is the impact on classic cardiometabolic risk factors of the more common treatments used in those women; Does the combination of the antiandrogenic therapy plus metformin have any impact on efficacy or cardiometabolic profile? We searched PubMed and EMBASE for articles published up to 16 September 2017. After deleting duplicates, the abstracts of 1522 articles were analysed. We subsequently excluded 1446 articles leaving 76 studies for full-text assessment of eligibility. Of them, 43 articles were excluded. Hence, 33 studies and 1521 women were included in the quantitative synthesis and in the meta-analyses. Meta-analyses calculated mean differences (MD), standardized mean differences (SMD), odds ratio (OR) and 95% CIs. Heterogeneity and inconsistency across studies was assessed by χ2 test and Higgins's I2 statistics. Quality and risk of bias of individual studies were assessed according to the Cochrane Handbook for Systematic Reviews of Interventions 5.1.0. We then used the approach recommended by the Grading of Recommendations, Assessments, Development, and Evaluation (GRADE) group to indicate the global quality of evidence for a selection of primary outcomes. Regarding efficacy, the MD in hirsutism score between COC and/or AA and metformin were not significant

Psychotherapy for chronic major depression and dysthymia: A meta analysis

NARCIS (Netherlands)

Cuijpers, P.; van Straten, A.; Schuurmans, J.; van Oppen, P.C.; Hollon, S.D.; Andersson, G.

2010-01-01

Although several studies have examined the effects of psychotherapy on chronic depression and dysthymia, no meta-analysis has been conducted to integrate results of these studies. We conducted a meta-analysis of 16 randomized trials examining the effects of psychotherapy on chronic depression and

Psychotherapy for chronic major depression and dysthymia: A meta analysis.

NARCIS (Netherlands)

Cuijpers, P.; van Straten, A.; Schuurmans, J.; van Oppen, P.C.; Hollon, S.D.; Andersson, G.

2009-01-01

Although several studies have examined the effects of psychotherapy on chronic depression and dysthymia, no meta-analysis has been conducted to integrate results of these studies. We conducted a meta-analysis of 16 randomized trials examining the effects of psychotherapy on chronic depression and

Does chocolate reduce blood pressure? A meta-analysis.

Science.gov (United States)

Ried, Karin; Sullivan, Thomas; Fakler, Peter; Frank, Oliver R; Stocks, Nigel P

2010-06-28

Dark chocolate and flavanol-rich cocoa products have attracted interest as an alternative treatment option for hypertension, a known risk factor for cardiovascular disease. Previous meta-analyses concluded that cocoa-rich foods may reduce blood pressure. Recently, several additional trials have been conducted with conflicting results. Our study summarises current evidence on the effect of flavanol-rich cocoa products on blood pressure in hypertensive and normotensive individuals. We searched Medline, Cochrane and international trial registries between 1955 and 2009 for randomised controlled trials investigating the effect of cocoa as food or drink compared with placebo on systolic and diastolic blood pressure (SBP/DBP) for a minimum duration of 2 weeks. We conducted random effects meta-analysis of all studies fitting the inclusion criteria, as well as subgroup analysis by baseline blood pressure (hypertensive/normotensive). Meta-regression analysis explored the association between type of treatment, dosage, duration or baseline blood pressure and blood pressure outcome. Statistical significance was set at P chocolate compared with control (mean BP change +/- SE: SBP: -3.2 +/- 1.9 mmHg, P = 0.001; DBP: -2.0 +/- 1.3 mmHg, P = 0.003). However, subgroup meta-analysis was significant only for the hypertensive or prehypertensive subgroups (SBP: -5.0 +/- 3.0 mmHg; P = 0.0009; DBP: -2.7 +/- 2.2 mm Hg, P = 0.01), while BP was not significantly reduced in the normotensive subgroups (SBP: -1.6 +/- 2.3 mmHg, P = 0.17; DBP: -1.3 +/- 1.6 mmHg, P = 0.12). Nine trials used chocolate containing 50% to 70% cocoa compared with white chocolate or other cocoa-free controls, while six trials compared high- with low-flavanol cocoa products. Daily flavanol dosages ranged from 30 mg to 1000 mg in the active treatment groups, and interventions ran for 2 to 18 weeks. Meta-regression analysis found study design and type of control to be borderline significant but possibly indirect predictors

Visual Task Demands and the Auditory Mismatch Negativity: An Empirical Study and a Meta-Analysis.

Science.gov (United States)

Wiens, Stefan; Szychowska, Malina; Nilsson, Mats E

2016-01-01

Because the auditory system is particularly useful in monitoring the environment, previous research has examined whether task-irrelevant, auditory distracters are processed even if subjects focus their attention on visual stimuli. This research suggests that attentionally demanding visual tasks decrease the auditory mismatch negativity (MMN) to simultaneously presented auditory distractors. Because a recent behavioral study found that high visual perceptual load decreased detection sensitivity of simultaneous tones, we used a similar task (n = 28) to determine if high visual perceptual load would reduce the auditory MMN. Results suggested that perceptual load did not decrease the MMN. At face value, these nonsignificant findings may suggest that effects of perceptual load on the MMN are smaller than those of other demanding visual tasks. If so, effect sizes should differ systematically between the present and previous studies. We conducted a selective meta-analysis of published studies in which the MMN was derived from the EEG, the visual task demands were continuous and varied between high and low within the same task, and the task-irrelevant tones were presented in a typical oddball paradigm simultaneously with the visual stimuli. Because the meta-analysis suggested that the present (null) findings did not differ systematically from previous findings, the available evidence was combined. Results of this meta-analysis confirmed that demanding visual tasks reduce the MMN to auditory distracters. However, because the meta-analysis was based on small studies and because of the risk for publication biases, future studies should be preregistered with large samples (n > 150) to provide confirmatory evidence for the results of the present meta-analysis. These future studies should also use control conditions that reduce confounding effects of neural adaptation, and use load manipulations that are defined independently from their effects on the MMN.

Visual Task Demands and the Auditory Mismatch Negativity: An Empirical Study and a Meta-Analysis

Science.gov (United States)

Wiens, Stefan; Szychowska, Malina; Nilsson, Mats E.

2016-01-01

Because the auditory system is particularly useful in monitoring the environment, previous research has examined whether task-irrelevant, auditory distracters are processed even if subjects focus their attention on visual stimuli. This research suggests that attentionally demanding visual tasks decrease the auditory mismatch negativity (MMN) to simultaneously presented auditory distractors. Because a recent behavioral study found that high visual perceptual load decreased detection sensitivity of simultaneous tones, we used a similar task (n = 28) to determine if high visual perceptual load would reduce the auditory MMN. Results suggested that perceptual load did not decrease the MMN. At face value, these nonsignificant findings may suggest that effects of perceptual load on the MMN are smaller than those of other demanding visual tasks. If so, effect sizes should differ systematically between the present and previous studies. We conducted a selective meta-analysis of published studies in which the MMN was derived from the EEG, the visual task demands were continuous and varied between high and low within the same task, and the task-irrelevant tones were presented in a typical oddball paradigm simultaneously with the visual stimuli. Because the meta-analysis suggested that the present (null) findings did not differ systematically from previous findings, the available evidence was combined. Results of this meta-analysis confirmed that demanding visual tasks reduce the MMN to auditory distracters. However, because the meta-analysis was based on small studies and because of the risk for publication biases, future studies should be preregistered with large samples (n > 150) to provide confirmatory evidence for the results of the present meta-analysis. These future studies should also use control conditions that reduce confounding effects of neural adaptation, and use load manipulations that are defined independently from their effects on the MMN. PMID:26741815

Meta-análise em pesquisas científicas: enfoque em metodologias Meta analysis in scientific research: a methodological approach

Directory of Open Access Journals (Sweden)

P.A. Lovatto

2007-07-01

Full Text Available Este texto descreve os princípios básicos de sistematização com enfoque em meta-análise. É apresentado o estado da arte da meta-análise, recuperando informações de sua evolução e metodologias básicas para sua realização. São descritos seus antecedentes históricos, os limites das abordagens clássicas de revisão de literatura, as bases conceituais, os objetivos e justificativas. É indicada uma metodologia geral para realização da meta-análise. São apresentados os critérios para a definição dos objetivos. São descritos os procedimentos de sistematização das informações e gestão de base bibliográfica de dados destinada aos estudos meta-analíticos (seleção, codificação, filtragem de dados. São apresentadas as análises mais comuns (gráfica, ponderações, a escolha do modelo estatístico (um fator explicativo qualitativo, um efeito qualitativo ou quantitativo, os fatores de interferência, os procedimentos pós-analíticos (variações residuais, heterogeneidade entre resultados. Em síntese, este texto mostra que a meta-análise é superior às formas tradicionais de revisão de literatura por estimar com maior precisão os efeitos dos tratamentos, ajustando-os para a heterogeneidade experimental. No entanto, a meta-análise exige os efeitos na sistematização e análise dos resultados da pesquisa.This text describes a basic approach of systematization with focus on meta-analysis. It is presented the art state of the meta-analysis, recovering information of its evolution and basic methodologies for its accomplishment. In this text are described the historical antecedents of meta-analysis, the limits of the classic approaches of literature review, the conceptual bases and the objectives. It is indicated a general methodology for meta-analysis procedures. The criteria for the definition of the objectives are presented. The procedures of the systematization and management of bibliographical data base selected to

Food and drug cues activate similar brain regions: a meta-analysis of functional MRI studies.

Science.gov (United States)

Tang, D W; Fellows, L K; Small, D M; Dagher, A

2012-06-06

In healthy individuals, food cues can trigger hunger and feeding behavior. Likewise, smoking cues can trigger craving and relapse in smokers. Brain imaging studies report that structures involved in appetitive behaviors and reward, notably the insula, striatum, amygdala and orbital frontal cortex, tend to be activated by both visual food and smoking cues. Here, by carrying out a meta-analysis of human neuro-imaging studies, we investigate the neural network activated by: 1) food versus neutral cues (14 studies, 142 foci) 2) smoking versus neutral cues (15 studies, 176 foci) 3) smoking versus neutral cues when correlated with craving scores (7 studies, 108 foci). PubMed was used to identify cue-reactivity imaging studies that compared brain response to visual food or smoking cues to neutral cues. Fourteen articles were identified for the food meta-analysis and fifteen articles were identified for the smoking meta-analysis. Six articles were identified for the smoking cue correlated with craving analysis. Meta-analyses were carried out using activation likelihood estimation. Food cues were associated with increased blood oxygen level dependent (BOLD) response in the left amygdala, bilateral insula, bilateral orbital frontal cortex, and striatum. Smoking cues were associated with increased BOLD signal in the same areas, with the exception of the insula. However, the smoking meta-analysis of brain maps correlating cue-reactivity with subjective craving did identify the insula, suggesting that insula activation is only found when craving levels are high. The brain areas identified here are involved in learning, memory and motivation, and their cue-induced activity is an index of the incentive salience of the cues. Using meta-analytic techniques to combine a series of studies, we found that food and smoking cues activate comparable brain networks. There is significant overlap in brain regions responding to conditioned cues associated with natural and drug rewards

Genome-wide meta-analysis in alopecia areata resolves HLA associations and reveals two new susceptibility loci

NARCIS (Netherlands)

Betz, Regina C; Petukhova, Lynn; Ripke, Stephan; Huang, Hailiang; Menelaou, Androniki; Redler, Silke; Becker, Tim; Heilmann, Stefanie; Yamany, Tarek; Duvic, Madeliene; Hordinsky, Maria; Norris, David; Price, Vera H; Mackay-Wiggan, Julian; de Jong, Annemieke; DeStefano, Gina M; Moebus, Susanne; Böhm, Markus; Blume-Peytavi, Ulrike; Wolff, Hans; Lutz, Gerhard; Kruse, Roland; Bian, Li; Amos, Christopher I; Lee, Annette; Gregersen, Peter K; Blaumeiser, Bettina; Altshuler, David; Clynes, Raphael; de Bakker, Paul I W; Nöthen, Markus M; Daly, Mark J; Christiano, Angela M

2015-01-01

Alopecia areata (AA) is a prevalent autoimmune disease with 10 known susceptibility loci. Here we perform the first meta-analysis of research on AA by combining data from two genome-wide association studies (GWAS), and replication with supplemented ImmunoChip data for a total of 3,253 cases and

Lateral Epicondylitis and Physical Exposure at Work? A Review of Prospective Studies and Meta-Analysis.

Science.gov (United States)

Descatha, Alexis; Albo, Francesco; Leclerc, Annette; Carton, Matthieu; Godeau, Diane; Roquelaure, Yves; Petit, Audrey; Aublet-Cuvelier, Agnès

2016-11-01

In view of recent published studies, a meta-analysis was undertaken on prospective studies in order to assess any association between lateral epicondylitis and physical exposure at work. Using the key words "lateral epicondylitis" AND "occupational" AND ("cohort" OR "longitudinal," OR "incidence") without limitations on the language or year of publication, original prospective studies were selected from 4 databases (PubMed, Scopus, Web of Science, and Base de Données de Santé Publique) after 2 rounds (valid design, valid association reported, and valid work exposure). Relevant associations between physical exposure at work and incident lateral epicondylitis were extracted from the articles, and a meta-risk was calculated using the generic variance approach (meta-odds ratios [meta-ORs]). From 2001 to 2014, 5 prospective studies were included. Among 6,922 included subjects (and 3,449 who were followed), 256 cases of incident lateral epicondylitis were diagnosed 2.5-6 years after baseline. All the published studies found a significant estimation of relative risk for a positive association between combined biomechanic exposure involving the wrist and/or elbow and incidence of lateral epicondylitis. The overall meta-OR was 2.6 (95% confidence interval 1.9-3.5), with a low heterogeneity (Q = 1.4, P > 0.05). Funnel plots and Egger's test did not suggest major publication bias. The results of this meta-analysis strongly support the hypothesis of an association between biomechanic exposure involving the wrist and/or elbow at work and incidence of lateral epicondylitis. © 2016, American College of Rheumatology.

Selenium Exposure and Cancer Risk: an Updated Meta-analysis and Meta-regression

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Cai, Xianlei; Wang, Chen; Yu, Wanqi; Fan, Wenjie; Wang, Shan; Shen, Ning; Wu, Pengcheng; Li, Xiuyang; Wang, Fudi

2016-01-01

The objective of this study was to investigate the associations between selenium exposure and cancer risk. We identified 69 studies and applied meta-analysis, meta-regression and dose-response analysis to obtain available evidence. The results indicated that high selenium exposure had a protective effect on cancer risk (pooled OR = 0.78; 95%CI: 0.73–0.83). The results of linear and nonlinear dose-response analysis indicated that high serum/plasma selenium and toenail selenium had the efficacy on cancer prevention. However, we did not find a protective efficacy of selenium supplement. High selenium exposure may have different effects on specific types of cancer. It decreased the risk of breast cancer, lung cancer, esophageal cancer, gastric cancer, and prostate cancer, but it was not associated with colorectal cancer, bladder cancer, and skin cancer. PMID:26786590

Claustrophobia in magnetic resonance imaging: A systematic review and meta-analysis

International Nuclear Information System (INIS)

Munn, Zachary; Moola, Sandeep; Lisy, Karolina; Riitano, Dagmara; Murphy, Fred

2015-01-01

Purpose: Anxiety and claustrophobia are common during MRI scanning. It has been estimated that 2 million scans worldwide cannot be performed annually either due to premature scan termination or refusal due to claustrophobia. The actual prevalence of claustrophobic reactions (defined here as scan terminations or refusals) reported in published studies varies significantly. Materials and methods: A systematic search was performed to identify literature on this topic. Studies were included if they assessed adults undergoing MRI and reported on claustrophobic reactions. Data on the proportion of patients who suffered a claustrophobic reaction was extracted and combined in a meta-analysis where possible. Following the search, 18 studies were retrieved that met the inclusion criteria. Results: There was significant clinical and statistical heterogeneity across the included studies, and data was only included in meta-analysis where there were comparable populations and scan. The pooled proportion for scan terminations due to claustrophobia equalled 1.18% (95% CI 0.79–1.65). Conclusion: The results of this review show that claustrophobia is an issue when undergoing MRI, with approximately 1 out of 100 or 12 out of 1000 people scanned experiencing a claustrophobic reaction requiring premature termination of the scan. Health professionals working in MRI should be prepared to encounter claustrophobic patients. - Highlights: • We reviewed all the published literature reporting on claustrophobic events during MRI. • Meta-analysis of these results shows that 1.2 people out of 100 have a claustrophobic event. • Health professionals working in MRI need to be prepared to encounter claustrophobic patients

Memory and Obstructive Sleep Apnea: A Meta-Analysis

Science.gov (United States)

Wallace, Anna; Bucks, Romola S.

2013-01-01

Study Objectives: To examine episodic memory performance in individuals with obstructive sleep apnea (OSA). Design Meta-analysis was used to synthesize results from individual studies examining the impact of OSA on episodic memory performance. The performance of individuals with OSA was compared to healthy controls or normative data. Participants Forty-two studies were included, comprising 2,294 adults with untreated OSA and 1,364 healthy controls. Studies that recorded information about participants at baseline prior to treatment interventions were included in the analysis. Measurements Participants were assessed with tasks that included a measure of episodic memory: immediate recall, delayed recall, learning, and/or recognition memory. Results: The results of the meta-analyses provide evidence that individuals with OSA are significantly impaired when compared to healthy controls on verbal episodic memory (immediate recall, delayed recall, learning, and recognition) and visuo-spatial episodic memory (immediate and delayed recall), but not visual immediate recall or visuo-spatial learning. When patients were compared to norms, negative effects of OSA were found only in verbal immediate and delayed recall. Conclusions: This meta-analysis contributes to understanding of the nature of episodic memory deficits in individuals with OSA. Impairments to episodic memory are likely to affect the daily functioning of individuals with OSA. Citation Wallace A; Bucks RS. Memory and obstructive sleep apnea: a meta-analysis. SLEEP 2013;36(2):203-220. PMID:23372268

Caffeine ingestion enhances Wingate performance: a meta-analysis.

Science.gov (United States)

Grgic, Jozo

2018-03-01

The positive effects of caffeine ingestion on aerobic performance are well-established; however, recent findings are suggesting that caffeine ingestion might also enhance components of anaerobic performance. A commonly used test of anaerobic performance and power output is the 30-second Wingate test. Several studies explored the effects of caffeine ingestion on Wingate performance, with equivocal findings. To elucidate this topic, this paper aims to determine the effects of caffeine ingestion on Wingate performance using meta-analytic statistical techniques. Following a search through PubMed/MEDLINE, Scopus, and SportDiscus ® , 16 studies were found meeting the inclusion criteria (pooled number of participants = 246). Random-effects meta-analysis of standardized mean differences (SMD) for peak power output and mean power output was performed. Study quality was assessed using the modified version of the PEDro checklist. Results of the meta-analysis indicated a significant difference (p = .005) between the placebo and caffeine trials on mean power output with SMD values of small magnitude (0.18; 95% confidence interval: 0.05, 0.31; +3%). The meta-analysis performed for peak power output indicated a significant difference (p = .006) between the placebo and caffeine trials (SMD = 0.27; 95% confidence interval: 0.08, 0.47 [moderate magnitude]; +4%). The results from the PEDro checklist indicated that, in general, studies are of good and excellent methodological quality. This meta-analysis adds on to the current body of evidence showing that caffeine ingestion can also enhance components of anaerobic performance. The results presented herein may be helpful for developing more efficient evidence-based recommendations regarding caffeine supplementation.

Systematic review and meta-analysis in cardiac surgery: a primer.

Science.gov (United States)

Yanagawa, Bobby; Tam, Derrick Y; Mazine, Amine; Tricco, Andrea C

2018-03-01

The purpose of this article is to review the strengths and weaknesses of systematic reviews and meta-analyses to inform our current understanding of cardiac surgery. A systematic review and meta-analysis of a focused topic can provide a quantitative estimate for the effect of a treatment intervention or exposure. In cardiac surgery, observational studies and small, single-center prospective trials provide most of the clinical outcomes that form the evidence base for patient management and guideline recommendations. As such, meta-analyses can be particularly valuable in synthesizing the literature for a particular focused surgical question. Since the year 2000, there are over 800 meta-analysis-related publications in our field. There are some limitations to this technique, including clinical, methodological and statistical heterogeneity, among other challenges. Despite these caveats, results of meta-analyses have been useful in forming treatment recommendations or in providing guidance in the design of future clinical trials. There is a growing number of meta-analyses in the field of cardiac surgery. Knowledge translation via meta-analyses will continue to guide and inform cardiac surgical practice and our practice guidelines.

When Is Hub Gene Selection Better than Standard Meta-Analysis?

Science.gov (United States)

Langfelder, Peter; Mischel, Paul S.; Horvath, Steve

2013-01-01

Since hub nodes have been found to play important roles in many networks, highly connected hub genes are expected to play an important role in biology as well. However, the empirical evidence remains ambiguous. An open question is whether (or when) hub gene selection leads to more meaningful gene lists than a standard statistical analysis based on significance testing when analyzing genomic data sets (e.g., gene expression or DNA methylation data). Here we address this question for the special case when multiple genomic data sets are available. This is of great practical importance since for many research questions multiple data sets are publicly available. In this case, the data analyst can decide between a standard statistical approach (e.g., based on meta-analysis) and a co-expression network analysis approach that selects intramodular hubs in consensus modules. We assess the performance of these two types of approaches according to two criteria. The first criterion evaluates the biological insights gained and is relevant in basic research. The second criterion evaluates the validation success (reproducibility) in independent data sets and often applies in clinical diagnostic or prognostic applications. We compare meta-analysis with consensus network analysis based on weighted correlation network analysis (WGCNA) in three comprehensive and unbiased empirical studies: (1) Finding genes predictive of lung cancer survival, (2) finding methylation markers related to age, and (3) finding mouse genes related to total cholesterol. The results demonstrate that intramodular hub gene status with respect to consensus modules is more useful than a meta-analysis p-value when identifying biologically meaningful gene lists (reflecting criterion 1). However, standard meta-analysis methods perform as good as (if not better than) a consensus network approach in terms of validation success (criterion 2). The article also reports a comparison of meta-analysis techniques applied to

When is hub gene selection better than standard meta-analysis?

Directory of Open Access Journals (Sweden)

Peter Langfelder

Full Text Available Since hub nodes have been found to play important roles in many networks, highly connected hub genes are expected to play an important role in biology as well. However, the empirical evidence remains ambiguous. An open question is whether (or when hub gene selection leads to more meaningful gene lists than a standard statistical analysis based on significance testing when analyzing genomic data sets (e.g., gene expression or DNA methylation data. Here we address this question for the special case when multiple genomic data sets are available. This is of great practical importance since for many research questions multiple data sets are publicly available. In this case, the data analyst can decide between a standard statistical approach (e.g., based on meta-analysis and a co-expression network analysis approach that selects intramodular hubs in consensus modules. We assess the performance of these two types of approaches according to two criteria. The first criterion evaluates the biological insights gained and is relevant in basic research. The second criterion evaluates the validation success (reproducibility in independent data sets and often applies in clinical diagnostic or prognostic applications. We compare meta-analysis with consensus network analysis based on weighted correlation network analysis (WGCNA in three comprehensive and unbiased empirical studies: (1 Finding genes predictive of lung cancer survival, (2 finding methylation markers related to age, and (3 finding mouse genes related to total cholesterol. The results demonstrate that intramodular hub gene status with respect to consensus modules is more useful than a meta-analysis p-value when identifying biologically meaningful gene lists (reflecting criterion 1. However, standard meta-analysis methods perform as good as (if not better than a consensus network approach in terms of validation success (criterion 2. The article also reports a comparison of meta-analysis techniques

When is hub gene selection better than standard meta-analysis?

Science.gov (United States)

Langfelder, Peter; Mischel, Paul S; Horvath, Steve

2013-01-01

Since hub nodes have been found to play important roles in many networks, highly connected hub genes are expected to play an important role in biology as well. However, the empirical evidence remains ambiguous. An open question is whether (or when) hub gene selection leads to more meaningful gene lists than a standard statistical analysis based on significance testing when analyzing genomic data sets (e.g., gene expression or DNA methylation data). Here we address this question for the special case when multiple genomic data sets are available. This is of great practical importance since for many research questions multiple data sets are publicly available. In this case, the data analyst can decide between a standard statistical approach (e.g., based on meta-analysis) and a co-expression network analysis approach that selects intramodular hubs in consensus modules. We assess the performance of these two types of approaches according to two criteria. The first criterion evaluates the biological insights gained and is relevant in basic research. The second criterion evaluates the validation success (reproducibility) in independent data sets and often applies in clinical diagnostic or prognostic applications. We compare meta-analysis with consensus network analysis based on weighted correlation network analysis (WGCNA) in three comprehensive and unbiased empirical studies: (1) Finding genes predictive of lung cancer survival, (2) finding methylation markers related to age, and (3) finding mouse genes related to total cholesterol. The results demonstrate that intramodular hub gene status with respect to consensus modules is more useful than a meta-analysis p-value when identifying biologically meaningful gene lists (reflecting criterion 1). However, standard meta-analysis methods perform as good as (if not better than) a consensus network approach in terms of validation success (criterion 2). The article also reports a comparison of meta-analysis techniques applied to

Testing moderation in network meta-analysis with individual participant data.

Science.gov (United States)

Dagne, Getachew A; Brown, C Hendricks; Howe, George; Kellam, Sheppard G; Liu, Lei

2016-07-10

Meta-analytic methods for combining data from multiple intervention trials are commonly used to estimate the effectiveness of an intervention. They can also be extended to study comparative effectiveness, testing which of several alternative interventions is expected to have the strongest effect. This often requires network meta-analysis (NMA), which combines trials involving direct comparison of two interventions within the same trial and indirect comparisons across trials. In this paper, we extend existing network methods for main effects to examining moderator effects, allowing for tests of whether intervention effects vary for different populations or when employed in different contexts. In addition, we study how the use of individual participant data may increase the sensitivity of NMA for detecting moderator effects, as compared with aggregate data NMA that employs study-level effect sizes in a meta-regression framework. A new NMA diagram is proposed. We also develop a generalized multilevel model for NMA that takes into account within-trial and between-trial heterogeneity and can include participant-level covariates. Within this framework, we present definitions of homogeneity and consistency across trials. A simulation study based on this model is used to assess effects on power to detect both main and moderator effects. Results show that power to detect moderation is substantially greater when applied to individual participant data as compared with study-level effects. We illustrate the use of this method by applying it to data from a classroom-based randomized study that involved two sub-trials, each comparing interventions that were contrasted with separate control groups. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Sensitivity analysis for publication bias in meta-analysis of diagnostic studies for a continuous biomarker.

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Hattori, Satoshi; Zhou, Xiao-Hua

2018-02-10

Publication bias is one of the most important issues in meta-analysis. For standard meta-analyses to examine intervention effects, the funnel plot and the trim-and-fill method are simple and widely used techniques for assessing and adjusting for the influence of publication bias, respectively. However, their use may be subjective and can then produce misleading insights. To make a more objective inference for publication bias, various sensitivity analysis methods have been proposed, including the Copas selection model. For meta-analysis of diagnostic studies evaluating a continuous biomarker, the summary receiver operating characteristic (sROC) curve is a very useful method in the presence of heterogeneous cutoff values. To our best knowledge, no methods are available for evaluation of influence of publication bias on estimation of the sROC curve. In this paper, we introduce a Copas-type selection model for meta-analysis of diagnostic studies and propose a sensitivity analysis method for publication bias. Our method enables us to assess the influence of publication bias on the estimation of the sROC curve and then judge whether the result of the meta-analysis is sufficiently confident or should be interpreted with much caution. We illustrate our proposed method with real data. Copyright © 2017 John Wiley & Sons, Ltd.

Cholelithiasis, cholecystectomy and risk of hepatocellular carcinoma: A meta-analysis

Directory of Open Access Journals (Sweden)

Lingyun Guo

2014-01-01

Full Text Available Available evidence of the relationship between cholelithiasis, cholecystectomy, and risk of liver cancer and hence we conducted a meta-analysis to investigate the relationships. PubMed, EMBASE, and ISI Web of Knowledge were searched to identify all published cohort studies and case-control studies that evaluated the relationships of cholelithiasis, cholecystectomy and risk of liver cancer and single-cohort studies which evaluated the incidence of liver cancer among patients who understood cholecystectomy (up to February 2013. Comprehensive meta-analysis software was used for meta-analysis. A total of 11 observational studies (six cohort studies and five case-control studies were included in this meta-analysis. The result from meta-analysis showed that cholecystectomy (risk ratio [RR]: 1.59, 95% confidence interval [CI]: 1.01-2.51, I2 = 72% and cholecystolithiasis (RR: 5.40, 95% CI: 3.69-7.89, I2 = 93% was associated with more liver cancer, especially for intrahepatic cholangiocarcinoma (ICC (cholecystectomy: RR: 3.51, 95% CI: 1.84-6.71, I2 = 26%; cholecystolithiasis: RR: 11.06, 95% CI: 6.99-17.52, I2 = 0%. The pooled standardized incidence rates (SIR of liver cancer in patients who understood cholecystectomy showed cholecystectomy might increase the incidence of liver cancer (SIR: 1.57, 95% CI: 1.13-2.20, I2 = 15%. Based on the results of the meta-analysis, cholecystectomy and cholecystolithiasis seemed to be involved in the development of liver cancer, especially for ICC. However, most available studies were case-control studies and short-term cohort studies, so the future studies should more long-term cohort studies should be well-conducted to evaluate the long-term relationship.

The efficacy of trimetazidine on stable angina pectoris: a meta-analysis of randomized clinical trials.

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Peng, Song; Zhao, Min; Wan, Jing; Fang, Qi; Fang, Dong; Li, Kaiyong

2014-12-20

This meta-analysis aimed to evaluate the efficacy of trimetazidine in combination with other anti-anginal drugs versus other anti-anginal drugs in the treatment of stable angina pectoris (SAP). Randomized controlled trials (RCTs) published in English and Chinese were retrieved from computerized databases: Embase, PubMed, and CNKI. Primary outcomes consist of clinical parameters (numbers of weekly angina attacks and nitroglycerin use) and ergometric parameters (time to 1mm ST-segment depression, and total work (in Mets) and exercise duration (in seconds) at peak exercise) in stable angina pectoris treated by trimetazidine or not. The quality of studies was evaluated using Jadad score. Data analysis of 13 studies was performed using Stata 12.0 software. Results showed that treatment of trimetazidine and other anti-anginal drugs was associated with a smaller weekly mean number of angina attacks (WMD=-0.95, 95%CI: -1.30 to -0.61, Z=5.39, Pangina pectoris. Sensitivity analysis was performed. Sub-group analysis showed that treatment duration was not a significant moderator and patients treated within 8 weeks and above 12 weeks had no difference in the outcomes addressed in this meta-analysis. No publish bias was detected. This meta-analysis confirms the efficacy of trimetazidine in the treatment of stable angina pectoris, in comparison with conventional antianginal agents, regardless of treatment duration. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Physical Activity and Cognitive Development: A Meta-Analysis.

Science.gov (United States)

Jackson, William M; Davis, Nicholas; Sands, Stephen A; Whittington, Robert A; Sun, Lena S

2016-10-01

inclusion. From these 18 studies, 8 were independently selected by 2 authors for inclusion in the final analysis; there were no selection discrepancies between authors with regard to the studies to be included. In all, 770 subjects were included, 339 in the control group and 431 in the intervention group. All 8 studies contained a measure of inhibitory control; no other domain of executive function was measured frequently enough to perform meta-analysis, so only measures of inhibitory control were pooled and analyzed. A Cohen d effect size was calculated for each measure using the method of Morris for controlled pre-post control measurement studies. The studies were then combined in a random effects model using Comprehensive Meta Analysis software (Biostat, Englewood, NJ) for Windows (Microsoft, Redmond, WA). All studies showed a positive effect of regular exercise with improvements in measures of inhibitory control, but none were statistically significant for this measure. When pooled, the model revealed a combined Cohen d effect size of 0.2 (95% confidence interval, 0.03-0.37; P=0.021), indicating a small improvement of inhibitory control with long-term physical activity. Heterogeneity was very low (I=0). Many studies used different neuropsychological tests to assess inhibitory control, which may have introduced unforeseen confounders. Other domains of executive functions were not measured frequently enough to perform meta-analysis. Despite attempts to gather unpublished data, positive results were observed in all of the included studies, raising the possibility of publication bias. Increased regular physical activity is associated with a small and measurable, improvement in neuropsychological tests of executive functions, specifically inhibitory control. Executive functions play an important role in complex behavior, and may contribute to academic and career achievement as well as success in social interaction. This finding provides support for the important interaction

The Effect of Hypnosis on Anxiety in Patients With Cancer: A Meta-Analysis.

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Chen, Pei-Ying; Liu, Ying-Mei; Chen, Mei-Ling

2017-06-01

Anxiety is a common form of psychological distress in patients with cancer. One recognized nonpharmacological intervention to reduce anxiety for various populations is hypnotherapy or hypnosis. However, its effect in reducing anxiety in cancer patients has not been systematically evaluated. This meta-analysis was designed to synthesize the immediate and sustained effects of hypnosis on anxiety of cancer patients and to identify moderators for these hypnosis effects. Qualified studies including randomized controlled trials (RCT) and pre-post design studies were identified by searching seven electronic databases: Scopus, Medline Ovidsp, PubMed, PsycInfo-Ovid, Academic Search Premier, CINAHL Plus with FT-EBSCO, and SDOL. Effect size (Hedges' g) was computed for each study. Random-effect modeling was used to combine effect sizes across studies. All statistical analyses were conducted with Comprehensive Meta-Analysis, version 2 (Biostat, Inc., Englewood, NJ, USA). Our meta-analysis of 20 studies found that hypnosis had a significant immediate effect on anxiety in cancer patients (Hedges' g: 0.70-1.41, p Hypnosis delivered by a therapist was significantly more effective than self-hypnosis. Hypnosis can reduce anxiety of cancer patients, especially for pediatric cancer patients who experience procedure-related stress. We recommend therapist-delivered hypnosis should be preferred until more effective self-hypnosis strategies are developed. © 2017 Sigma Theta Tau International.

Exercise and Bone Density: Meta-Analysis

National Research Council Canada - National Science Library

Kelley, George A; Sharpe-Kelley, Kristi

2007-01-01

.... Since no meta-analysis had existed using individual patient data (IPD) to examine the effects of exercise on BMD, our second two-year period of funding was devoted to examining the feasibility...

Circulating folate levels and colorectal adenoma: a case-control study and a meta-analysis.

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Park, Yeong Mi; Youn, Jiyoung; Cho, Chang Ho; Kim, Sung Hi; Lee, Jung Eun

2017-10-01

The relationship between folate and colorectal neoplasia remains controversial. We examined the association between serum folate concentrations and colorectal adenomas in a case-control study of Korean adults and conducted a meta-analysis. Our case-control study included 113 pairs of case and control who underwent colonoscopy and provided blood samples. We used multivariable conditional logistic regression models to obtain the odds ratios and 95% confidence interval (CIs). For meta-analysis, we identified the relevant studies by searching the PubMed database up to February 2017, included our case-control study and combined the study-specific relative risks (RRs) using a random-effects model. In this case-control study, we included 58 men and 55 women with colorectal adenomas and sex and fasting status matched the controls. We did not find any significant association between the serum folate levels and colorectal adenomas in either men or women. For meta-analysis, a total of eleven studies were included in our analysis and classified into two groups; polyp clearance group (PC) for the studies that included participants who underwent endoscopies and had their polyps removed at baseline; and no polyp clearance group (NPC) for the studies that included participants whose histories of endoscopies were unknown or who underwent their first endoscopies. Four PC (1,311 cases and 1,672 non-cases) and eight NPC studies (3,501 cases and 11,347 non-cases) were included. The combined RRs (95% CIs) comparing the bottom with the top categories of circulating folate levels were 1.07 (0.97-1.18) for the NPC group but 1.45 (1.16-1.74) for the PC group. Low circulating folate levels were associated with new adenoma formation.

Myo-inositol effects in women with PCOS: a meta-analysis of randomized controlled trials

Directory of Open Access Journals (Sweden)

Vittorio Unfer1,

2017-10-01

Full Text Available Myo-inositol (MI supplementation in women with polycystic ovary syndrome (PCOS has been evaluated over the last years. Many hormonal and reproductive impairments associated with this disorder seem relieved by the supplement. The objective of the meta-analysis was to assess the effects of MI alone or combined with d-chiro-inositol (DCI on the endocrine and metabolic abnormalities of women with PCOS. Literature was retrieved from selected databases, MEDLINE, EMBASE, PubMed and Research Gate (up to November 2016. Only randomized controlled trials (RCTs investigating the effects of MI alone or combined with DdCI were reviewed. Nine RCTs involving 247 cases and 249 controls were included. Significant decreases in fasting insulin (SMD = −1.021 μU/mL, 95% CI: −1.791 to −0.251, P = 0.009 and homeostasis model assessment (HOMA index (SMD = −0.585, 95% CI: −1.145 to −0.025, P = 0.041 were identified after MI supplementation. The trial sequential analysis of insulin meta-analysis illustrates that the cumulative z-curve crossed the monitoring boundary, providing firm evidence of the intervention effect. A slight trend toward a reduction of testosterone concentration by MI with respect to controls was found (SMD = −0.49, 95% CI: −1.072 to 0.092, P = 0.099, whereas androstenedione levels remained unaffected. Throughout a subgroup’s meta-analysis, a significant increase in serum SHBG was observed only in those studies where MI was administered for at least 24 weeks (SMD = 0.425 nmol/L, 95% CI: 0.050–0.801, P = 0.026. These results highlight the beneficial effect of MI in improving the metabolic profile of women with PCOS, concomitantly reducing their hyperandrogenism.

Effectiveness of Mobile Devices on Vocabulary Learning: A Meta-Analysis

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Mahdi, Hassan Saleh

2018-01-01

Mobile devices are considered as the most widely used information and communication technologies. They have provided great advantages in language learning. This study reports a meta-analysis of the effectiveness of using mobile devices on vocabulary learning. A meta-analysis was conducted on research that compared the outcomes from students…

Impact of evergreening on patients and health insurance: a meta analysis and reimbursement cost analysis of citalopram/escitalopram antidepressants.

Science.gov (United States)

Alkhafaji, Ali A; Trinquart, Ludovic; Baron, Gabriel; Desvarieux, Moïse; Ravaud, Philippe

2012-11-20

"Evergreening" refers to the numerous strategies whereby owners of pharmaceutical products use patent laws and minor drug modifications to extend their monopoly privileges on the drug. We aimed to evaluate the impact of evergreening through the case study of the antidepressant citalopram and its chiral switch form escitalopram by evaluating treatment efficacy and acceptability for patients, as well as health insurance costs for society. To assess efficacy and acceptability, we performed meta-analyses for efficacy and acceptability. We compared direct evidence (meta-analysis of results of head-to-head trials) and indirect evidence (adjusted indirect comparison of results of placebo-controlled trials). To assess health insurance costs, we analyzed individual reimbursement data from a representative sample of the French National Health Insurance Inter-regime Information System (SNIIR-AM) from 2003 to 2010, which allowed for projecting these results to the whole SNIIR-AM population (53 million people). In the meta-analysis of seven head-to-head trials (2,174 patients), efficacy was significantly better for escitalopram than citalopram (combined odds ratio (OR) 1.60 (95% confidence interval 1.05 to 2.46)). However, for the adjusted indirect comparison of 10 citalopram and 12 escitalopram placebo-controlled trials, 2,984 and 3,777 patients respectively, efficacy was similar for the two drug forms (combined indirect OR 1.03 (0.82 to 1.30)). Because of the discrepancy, we could not combine direct and indirect data (test of inconsistency, P = 0.07). A similar discrepancy was found for treatment acceptability. The overall reimbursement cost burden for the citalopram, escitalopram and its generic forms was 120.6 million Euros in 2010, with 96.8 million Euros for escitalopram. The clinical benefit of escitalopram versus citalopram remains uncertain. In our case of evergreening, escitalopram represented a substantially high proportion of the overall reimbursement cost burden as

Classifying oxidative stress by F2-isoprostane levels across human diseases: A meta-analysis.

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van 't Erve, Thomas J; Kadiiska, Maria B; London, Stephanie J; Mason, Ronald P

2017-08-01

The notion that oxidative stress plays a role in virtually every human disease and environmental exposure has become ingrained in everyday knowledge. However, mounting evidence regarding the lack of specificity of biomarkers traditionally used as indicators of oxidative stress in human disease and exposures now necessitates re-evaluation. To prioritize these re-evaluations, published literature was comprehensively analyzed in a meta-analysis to quantitatively classify the levels of systemic oxidative damage across human disease and in response to environmental exposures. In this meta-analysis, the F 2 -isoprostane, 8-iso-PGF 2α , was specifically chosen as the representative marker of oxidative damage. To combine published values across measurement methods and specimens, the standardized mean differences (Hedges' g) in 8-iso-PGF 2α levels between affected and control populations were calculated. The meta-analysis resulted in a classification of oxidative damage levels as measured by 8-iso-PGF 2α across 50 human health outcomes and exposures from 242 distinct publications. Relatively small increases in 8-iso-PGF 2α levels (ganalysis of published data. This analysis provides knowledge on the true involvement of oxidative damage across human health outcomes as well as utilizes past research to prioritize those conditions requiring further scrutiny on the mechanisms of biomarker generation. Copyright © 2017. Published by Elsevier B.V.

Prediction of miscarriage in women with viable intrauterine pregnancy-A systematic review and diagnostic accuracy meta-analysis.

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Pillai, Rekha N; Konje, Justin C; Richardson, Matthew; Tincello, Douglas G; Potdar, Neelam

2018-01-01

Both ultrasound and biochemical markers either alone or in combination have been described in the literature for the prediction of miscarriage. We performed this systematic review and meta-analysis to determine the best combination of biochemical, ultrasound and demographic markers to predict miscarriage in women with viable intrauterine pregnancy. The electronic database search included Medline (1946-June 2017), Embase (1980-June 2017), CINAHL (1981-June 2017) and Cochrane library. Key MESH and Boolean terms were used for the search. Data extraction and collection was performed based on the eligibility criteria by two authors independently. Quality assessment of the individual studies was done using QUADAS 2 (Quality Assessment for Diagnostic Accuracy Studies-2: A Revised Tool) and statistical analysis performed using the Cochrane systematic review manager 5.3 and STATA vs.13.0. Due to the diversity of the combinations used for prediction in the included papers it was not possible to perform a meta-analysis on combination markers. Therefore, we proceeded to perform a meta-analysis on ultrasound markers alone to determine the best marker that can help to improve the diagnostic accuracy of predicting miscarriage in women with viable intrauterine pregnancy. The systematic review identified 18 eligible studies for the quantitative meta-analysis with a total of 5584 women. Among the ultrasound scan markers, fetal bradycardia (n=10 studies, n=1762 women) on hierarchical summary receiver operating characteristic showed sensitivity of 68.41%, specificity of 97.84%, positive likelihood ratio of 31.73 (indicating a large effect on increasing the probability of predicting miscarriage) and negative likelihood ratio of 0.32. In studies for women with threatened miscarriage (n=5 studies, n=771 women) fetal bradycardia showed further increase in sensitivity (84.18%) for miscarriage prediction. Although there is gestational age dependent variation in the fetal heart rate, a plot

Hydropower externalities: a meta analysis

NARCIS (Netherlands)

Mattmann, M.; Logar, I.; Brouwer, R.

2016-01-01

This paper presents a meta-analysis of existing research related to the economic valuation of the external effects of hydropower. A database consisting of 81 observations derived from 29 studies valuing the non-market impacts of hydropower electricity generation is constructed with the main aim to

LncRNA expression and implication in osteosarcoma: a systematic review and meta-analysis

Directory of Open Access Journals (Sweden)

Wang Y

2017-11-01

Full Text Available Ying Wang,1,2,* Yuelong Huang,2,* Peng Xiang,3 Wei Tian2 1Department of Molecular Orthopaedics, Beijing Institute of Traumatology and Orthopaedics, 2Department of Spinal Surgery, Beijing Jishuitan Hospital, The Fourth Clinical Medical College of Peking University, 3Department of Urology, Peking University First Hospital, Beijing, People’s Republic of China *These authors contributed equally to this work Purpose: Osteosarcoma is the most prevalent primary bone tumor in children, adolescents, and older adults, typically presenting with poor survival outcomes. In recent years, ample evidence has shown that many long noncoding RNAs (lncRNAs have been aberrantly expressed in osteosarcoma, demonstrating their potential to serve as prognostic markers. In this study, we performed a meta-analysis on four lncRNAs (TUG1, UCA1, BCAR4, and HULC to systematically evaluate their prognostic value in osteosarcoma.Materials and methods: The eligible articles were systematically searched in PubMed, Web of Science, Embase, and Elsevier ScienceDirect (up to September 22, 2017, and one meta-analysis concerning the association between lncRNA expression and the overall survival (OS of osteosarcoma patients was performed. Survival outcomes were analyzed by OS. Subgroup analyses were performed.Results: A total of 1,361 patients with osteosarcoma and 12 lncRNAs from 16 articles were included in the study. Of the listed lncRNAs, the high expression of 10 lncRNAs indicated worse survival outcomes, while only two lncRNAs were shown to positively affect patients’ OS.Conclusion: This meta-analysis indicated that the abnormally expressed lncRNAs might significantly affect the survival of osteosarcoma patients. Combined use of these lncRNAs may serve as potential novel biomarkers for the indication of clinical outcomes of osteosarcoma patients as well as the selection of adjuvant chemotherapy strategies for clinical treatment of this disease. Keywords: lncRNAs, osteosarcoma

Urban-rural differences in childhood and adolescent obesity in the United States: a systematic review and meta-analysis.

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Johnson, James Allen; Johnson, Asal Mohamadi

2015-06-01

A systematic literature review and subsequent meta-analysis were performed to investigate differences in childhood obesity between urban and rural areas in the United States. A search of published studies comparing childhood obesity in urban and rural settings was undertaken by probing PubMed and Cumulative Index to Nursing and Allied Health Literature (CINAHL) for articles that met predetermined inclusion criteria. A subsequent meta-analysis was conducted to determine the combined effect size and significance of differences in childhood obesity between urban and rural areas. Ten studies were identified for systematic review, five of which contributed to the meta-analysis. All but one study suggested that residence in rural areas was associated with higher prevalence or increased odds of childhood obesity, compared to children living in urban areas. A meta-analysis of 74,168 pooled participants ages 2-19 found that rural children have 26% greater odds of obesity, compared to urban children (odds ratio=1.26; 95% confidence interval, 1.21-1.32). Obesity rates are higher among rural children than urban children in the United States. To ensure successful targeted interventions and effective resource allocation, practitioners and policy makers alike should be cognizant of this disparity in childhood obesity.

SLC6A3 polymorphism and response to methylphenidate in children with ADHD: A systematic review and meta-analysis.

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Soleimani, Robabeh; Salehi, Zivar; Soltanipour, Soheil; Hasandokht, Tolou; Jalali, Mir Mohammad

2018-04-01

Methylphenidate (MPH) is the most commonly used treatment for attention-deficit hyperactivity disorder (ADHD) in children. However, the response to MPH is not similar in all patients. This meta-analysis investigated the potential role of SLC6A3 polymorphisms in response to MPH in children with ADHD. Clinical trials or naturalistic studies were selected from electronic databases. A meta-analysis was conducted using a random-effects model. Cohen's d effect size and 95% confidence intervals (CIs) were determined. Sensitivity analysis and meta-regression were performed. Q-statistic and Egger's tests were conducted to evaluate heterogeneity and publication bias, respectively. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was used to assess the quality of evidence. Sixteen studies with follow-up periods of 1-28 weeks were eligible. The mean treatment acceptability of MPH was 97.2%. In contrast to clinical trials, the meta-analysis of naturalistic studies indicated that children without 10/10 repeat carriers had better response to MPH (Cohen's d: -0.09 and 0.44, respectively). The 9/9 repeat polymorphism had no effect on the response rate (Cohen's d: -0.43). In the meta-regression, a significant association was observed between baseline severity of ADHD, MPH dosage, and combined type of ADHD in some genetic models. Sensitivity analysis indicated the robustness of our findings. No publication bias was observed in our meta-analysis. The GRADE evaluations revealed very low levels of confidence for each outcome of response to MPH. The results of clinical trials and naturalistic studies regarding the effect size between different polymorphisms of SLC6A3 were contradictory. Therefore, further research is recommended. © 2017 Wiley Periodicals, Inc.

Association between Hypertension and Epistaxis: Systematic Review and Meta-analysis.

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Min, Hyun Jin; Kang, Hyun; Choi, Geun Joo; Kim, Kyung Soo

2017-12-01

Objective Whether there is an association or a cause-and-effect relationship between epistaxis and hypertension is a subject of longstanding controversy. The objective of this systematic review and meta-analysis was to determine the association between epistaxis and hypertension and to verify whether hypertension is an independent risk factor of epistaxis. Data Sources A comprehensive search was performed using the MEDLINE, EMBASE, and Cochrane Library databases. Review Methods The review was performed according to the Meta-analysis of Observational Studies in Epidemiology guidelines and reported using the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. Results We screened 2768 unique studies and selected 10 for this meta-analysis. Overall, the risk of epistaxis was significantly increased for patients with hypertension (odds ratio, 1.532 [95% confidence interval (CI), 1.181-1.986]; number needed to treat, 14.9 [95% CI, 12.3-19.0]). Results of the Q test and I 2 statistics suggested considerable heterogeneity ([Formula: see text] = 0.038, I 2 = 49.3%). The sensitivity analysis was performed by excluding 1 study at a time, and it revealed no change in statistical significance. Conclusion Although this meta-analysis had some limitations, our study demonstrated that hypertension was significantly associated with the risk of epistaxis. However, since this association does not support a causal relationship between hypertension and epistaxis, further clinical trials with large patient populations will be required to determine the impact of hypertension on epistaxis.

Cell-Free DNA in Metastatic Colorectal Cancer: A Systematic Review and Meta-Analysis.

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Spindler, Karen-Lise G; Boysen, Anders K; Pallisgård, Niels; Johansen, Julia S; Tabernero, Josep; Sørensen, Morten M; Jensen, Benny V; Hansen, Torben F; Sefrioui, David; Andersen, Rikke F; Brandslund, Ivan; Jakobsen, Anders

2017-09-01

Circulating DNA can be detected and quantified in the blood of cancer patients and used for detection of tumor-specific genetic alterations. The clinical utility has been intensively investigated for the past 10 years. The majority of reports focus on analyzing the clinical potential of tumor-specific mutations, whereas the use of total cell-free DNA (cfDNA) quantification is somehow controversial and sparsely described in the literature, but holds important clinical information in itself. The purpose of the present report was to present a systematic review and meta-analysis of the prognostic value of total cfDNA in patients with metastatic colorectal cancer (mCRC) treated with chemotherapy. In addition, we report on the overall performance of cfDNA as source for KRAS mutation detection. A systematic literature search of PubMed and Embase was performed by two independent investigators. Eligibility criteria were (a) total cfDNA analysis, (b) mCRC, and (c) prognostic value during palliative treatment. The preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines were followed, and meta-analysis applied on both aggregate data extraction and individual patients' data. Ten eligible cohorts were identified, including a total of 1,076 patients. Seven studies used quantitative polymerase chain reaction methods, two BEAMing [beads, emulsification, amplification, and magnetics] technology, and one study digital droplet polymerase chain reaction. The baseline levels of cfDNA was similar in the presented studies, and all studies reported a clear prognostic value in favor of patients with lowest levels of baseline cfDNA. A meta-analysis revealed a combined estimate of favorable overall survival hazard ratio (HR) in patients with levels below the median cfDNA (HR = 2.39, 95% confidence interval 2.03-2.82, p  meta-analysis. Reliable prognostic markers could help to guide patients and treating physicians regarding the relevance and choice of

Small and inconsistent effects of whole body vibration on athletic performance : a systematic review and meta-analysis

NARCIS (Netherlands)

Hortobagyi, Tibor; Lesinski, Melanie; Fernandez-del-Olmo, Miguel; Granacher, Urs

We quantified the acute and chronic effects of whole body vibration on athletic performance or its proxy measures in competitive and/or elite athletes. Systematic literature review and meta-analysis. Whole body vibration combined with exercise had an overall 0.3 % acute effect on maximal voluntary

Combined FDG-PET/CT for the detection of unknown primary tumors: systematic review and meta-analysis

International Nuclear Information System (INIS)

Kwee, Thomas C.; Kwee, Robert M.

2009-01-01

The aim of this study was to systematically review and meta-analyze published data on the diagnostic performance of combined 18F-fluoro-2-deoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) in the detection of primary tumors in patients with cancer of unknown primary (CUP). A systematic search for relevant studies was performed of the PubMed/MEDLINE and Embase databases. Methodological quality of the included studies was assessed. Reported detection rates, sensitivities and specificities were meta-analyzed. Subgroup analyses were performed if results of individual studies were heterogeneous. The 11 included studies, comprising a total sample size of 433 patients with CUP, had moderate methodological quality. Overall primary tumor detection rate, pooled sensitivity and specificity of FDG-PET/CT were 37%, 84% (95% CI 78-88%) and 84% (95% CI 78-89%), respectively. Sensitivity was heterogeneous across studies (P = 0.0001), whereas specificity was homogeneous across studies (P = 0.2114). Completeness of diagnostic workup before FDG-PET/CT, location of metastases of unknown primary, administration of CT contrast agents, type of FDG-PET/CT images evaluated and way of FDG-PET/CT review did not significantly influence diagnostic performance. In conclusion, FDG-PET/CT can be a useful method for unknown primary tumor detection. Future studies are required to prove the assumed advantage of FDG-PET/CT over FDG-PET alone and to further explore causes of heterogeneity. (orig.)

Citation analysis of meta-analysis articles on posttraumatic stress disorder.

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Liao, Xi-Ming; Chen, Ping-Yan

2011-04-01

In the past two decades enormously scientific researches on posttraumatic stress disorder (PTSD) have been undertaken and many related meta-analyses have been published. Citation analysis was used to get comprehensive perspectives of meta-analysis articles (MA articles) on PTSD for the purpose of facilitating the researchers, physicians and policy-makers to understand the PTSD. MA articles on PTSD in any languages from January 1980 to March 2009 were included if they presented meta-analytical methods and received at least one citation recorded in the Web of Science (WoS). Whereas studies, in which any effect sizes of PTSD were not distinguished from other psychological disorders, were excluded. Citations to and by identified MA articles were documented basing on records in WoS. Citation analysis was used to examine distribution patterns of characteristics and citation impact of MA articles on PTSD. Canonical analysis was used to explore the relationship between the characteristics of MA articles and citation impact. Thirty-four MA articles published during 1998 and 2008 were identified and revealed multiple study topics on PTSD: 10 (29.4%) were about epidemiology, 13 (38.2%) about treatment or intervention, 6 (17.6%) about pathophysiology or neurophysiology or neuroendocrine, 3 (8.8%) about childhood and 2 (5.9%) about psychosocial adversity. Two articles cited most frequently with 456 and 145 counts were published in Journal of Consulting and Clinical Psychology by Brewin (2000) and Psychological Bulletin by Ozer (2003), respectively. Mean cited count was 7.48 ± 10.56 and mean age (year 2009 minus article publication year) was (4.24 ± 2.91) years. They had been cited approximately by 67 disciplines and by authors from 42 countries or territories. Characteristics of meta-analysis highly correlated with citation impact and reflected by canonical correlation of 0.899 (P < 0.000 01). The age of MA articles predicted their citation impact. Citation analysis would

Biomechanical Differences of Foot-Strike Patterns During Running: A Systematic Review With Meta-analysis.

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Almeida, Matheus O; Davis, Irene S; Lopes, Alexandre D

2015-10-01

Systematic review with meta-analysis. To determine the biomechanical differences between foot-strike patterns used when running. Strike patterns during running have received attention in the recent literature due to their potential mechanical differences and associated injury risks. Electronic databases (MEDLINE, Embase, LILACS, SciELO, and SPORTDiscus) were searched through July 2014. Studies (cross-sectional, case-control, prospective, and retrospective) comparing the biomechanical characteristics of foot-strike patterns during running in distance runners at least 18 years of age were included in this review. Two independent reviewers evaluated the risk of bias. A meta-analysis with a random-effects model was used to combine the data from the included studies. Sixteen studies were included in the final analysis. In the meta-analyses of kinematic variables, significant differences between forefoot and rearfoot strikers were found for foot and knee angle at initial contact and knee flexion range of motion. A forefoot-strike pattern resulted in a plantar-flexed ankle position and a more flexed knee position, compared to a dorsiflexed ankle position and a more extended knee position for the rearfoot strikers, at initial contact with the ground. In the comparison of rearfoot and midfoot strikers, midfoot strikers demonstrated greater ankle dorsiflexion range of motion and decreased knee flexion range of motion compared to rearfoot strikers. For kinetic variables, the meta-analysis revealed that rearfoot strikers had higher vertical loading rates compared to forefoot strikers. There are differences in kinematic and kinetic characteristics between foot-strike patterns when running. Clinicians should be aware of these characteristics to help in the management of running injuries and advice on training.

Combined Effect of Levels in Personal Self-Regulation and Regulatory Teaching on Meta-Cognitive, on Meta-Motivational, and on Academic Achievement Variables in Undergraduate Students.

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de la Fuente, Jesús; Sander, Paul; Martínez-Vicente, José M; Vera, Mariano; Garzón, Angélica; Fadda, Salvattore

2017-01-01

The Theory of Self- vs . Externally-Regulated Learning™ (SRL vs. ERL) proposed different types of relationships among levels of variables in Personal Self-Regulation (PSR) and Regulatory Teaching (RT) to predict the meta-cognitive, meta-motivational and -emotional variables of learning, and of Academic Achievement in Higher Education. The aim of this investigation was empirical in order to validate the model of the combined effect of low-medium-high levels in PSR and RT on the dependent variables. For the analysis of combinations, a selected sample of 544 undergraduate students from two Spanish universities was used. Data collection was obtained from validated instruments, in Spanish versions. Using an ex-post-facto design, different Univariate and Multivariate Analyses (3 × 1, 3 × 3, and 4 × 1) were conducted. Results provide evidence for a consistent effect of low-medium-high levels of PSR and of RT, thus giving significant partial confirmation of the proposed rational model. As predicted, (1) the levels of PSR and positively and significantly effected the levels of learning approaches, resilience, engagement, academic confidence, test anxiety, and procedural and attitudinal academic achievement; (2) the most favorable type of interaction was a high level of PSR with a high level RT process. The limitations and implications of these results in the design of effective teaching are analyzed, to improve university teaching-learning processes.

Prognosis of Combining Remaining Teeth and Implants in Double-Crown-Retained Removable Dental Prostheses: A Systematic Review and Meta-Analysis.

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Lian, Meifei; Zhao, Kai; Feng, Yunzhi; Yao, Qian

The reliability of combining natural teeth and implants in one removable prosthesis is controversial. This systematic review was conducted to evaluate the prognosis of combined tooth/implant-supported double-crown-retained removable dental prostheses (DCR-RDPs) and to compare them with solely implant-supported prostheses with a minimum observation period of 3 years. Electronic database (PubMed, Embase, Central, and SCI) and manual searches up to August 2016 were conducted to identify human clinical studies on tooth/implant-supported DCR-RDPs. Literature selection and data extraction were accomplished by two independent reviewers. Meta-analyses of survival and complication rates were performed separately for combined tooth/implant-supported and solely implant-supported DCRRDPs. Among the initially identified 366 articles, 17 were included in a quantitative analysis. The estimated overall cumulative survival rate (CSR) for implants in combined tooth/implant-supported DCRRDPs was 98.72% (95% confidence interval [95% CI]: 96.98% to 99.82%), and that for implants in solely implant-supported DCR-RDPs was 98.83% (95% CI: 97.45% to 99.75%). The summary CSR for abutment teeth was 92.96% (95% CI: 85.38% to 98.12%). Double-crown-retained dentures with both abutment types showed high CSRs, most of which were approximately 100%. Regarding prosthetic maintenance treatment, the estimated incidence for patients treated with combined tooth/implant-supported RDPs was 0.164 (95% CI: 0.089 to 0.305) per patient per year (T/P/Y) and that for patients restored with solely implant-supported RDPs was 0.260 (95% CI: 0.149 to 0.454) T/P/Y. Based on four studies with combined tooth/implant-supported DCR-RDPs, no intrusion phenomena were encountered. Subject to the limitations of the present review, combining remaining teeth and implants in DCR-RDPs is a reliable and predictable treatment modality for partially edentulous patients. Comparable high survival rates and minor biologic or

Allergies and risk of head and neck cancer: an original study plus meta-analysis.

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Hsiao, Jenn-Ren; Ou, Chun-Yen; Lo, Hung-I; Huang, Cheng-Chih; Lee, Wei-Ting; Huang, Jehn-Shyun; Chen, Ken-Chung; Wong, Tung-Yiu; Tsai, Sen-Tien; Yen, Chia-Jui; Wu, Yuan-Hua; Hsueh, Wei-Ting; Yang, Ming-Wei; Wu, Shang-Yin; Chang, Jang-Yang; Chang, Kwang-Yu; Lin, Chen-Lin; Wang, Fang-Ting; Wang, Yi-Hui; Weng, Ya-Ling; Yang, Han-Chien; Chang, Jeffrey S

2013-01-01

Although the relationship between allergy and cancer has been investigated extensively, the role of allergy in head and neck cancer (HNC) appears less consistent. It is not clear whether allergies can independently influence the risk of HNC in the presence of known strong environmental risk factors, including consumption of alcohol, betel quid, and cigarette. THE CURRENT PAPER REPORTS RESULTS FROM: 1) an original hospital-based case-control study, which included 252 incident cases of HNC and 236 controls frequency-matched to cases on sex and age; and 2) a meta-analysis combining the results of the current case-control study and 13 previously published studies (9 cohort studies with 727,569 subjects and 550 HNC outcomes and 5 case-control studies with 4,017 HNC cases and 10,928 controls). In the original case-control study, we observed a strong inverse association between allergies and HNC [odds ratio = 0.41, 95% confidence interval (CI): 0.27-0.62]. The meta-analysis also indicated a statistically significant inverse association between HNC and allergies [meta-relative risk (RR) = 0.76, 95% CI: 0.63-0.91], particularly strong for allergic rhinitis (meta-RR = 0.55, 95% CI: 0.40-0.76). In addition, the inverse association between allergies and HNC was observed only among men (meta-RR = 0.67, 95% CI: 0.54-0.84) but not among women (meta-RR = 0.98, 95% CI: 0.81-1.18). These findings suggest that immunity plays an influential role in the risk of HNC. Future studies investigating immune biomarkers, including cytokine profiles and genetic polymorphisms, are warranted to further delineate the relationship between allergies and HNC. Understanding the relationship between allergies and HNC may help devise effective strategies to reduce and treat HNC.

Age, the psychological contract, and job attitudes : a meta-analysis

NARCIS (Netherlands)

Bal, P. Matthijs; de Lange, Annet H.; Jansen, Paul G. W.; van der Velde, Mandy E. G.

Age, the psychological contract, and job attitudes: a meta-analysis P.M. Bal, A H. De Lange, P.G.W Jansen Er M.E G Van der Velde, Gedrag en Organisatie, volume 23, March 2010, nr 1, pp 44-72. The meta-analysis investigated the relations between age and psychological contracts It was expected that

A Bayesian network meta-analysis on second-line systemic therapy in advanced gastric cancer.

Science.gov (United States)

Zhu, Xiaofu; Ko, Yoo-Joung; Berry, Scott; Shah, Keya; Lee, Esther; Chan, Kelvin

2017-07-01

It is unclear which regimen is the most efficacious among the available therapies for advanced gastric cancer in the second-line setting. We performed a network meta-analysis to determine their relative benefits. We conducted a systematic review of randomized controlled trials (RCTs) through the MEDLINE, Embase, and Cochrane Central Register of Controlled Trials databases and American Society of Clinical Oncology abstracts up to June 2014 to identify phase III RCTs on advanced gastric cancer in the second-line setting. Overall survival (OS) data were the primary outcome of interest. Hazard ratios (HRs) were extracted from the publications on the basis of reported values or were extracted from survival curves by established methods. A Bayesian network meta-analysis was performed with WinBUGS to compare all regimens simultaneously. Eight RCTs (2439 patients) were identified and contained extractable data for quantitative analysis. Network meta-analysis showed that paclitaxel plus ramucirumab was superior to single-agent ramucirumab [OS HR 0.51, 95 % credible region (CR) 0.30-0.86], paclitaxel (OS HR 0.81, 95 % CR 0.68-0.96), docetaxel (OS HR 0.56, 95 % CR 0.33-0.94), and irinotecan (OS HR 0.71, 95 % CR 0.52-0.99). Paclitaxel plus ramucirumab also had an 89 % probability of being the best regimen among all these regimens. Single-agent ramucirumab, paclitaxel, docetaxel, and irinotecan were comparable to each other with respect to OS and were superior to best supportive care. This is the first network meta-analysis to compare all second-line regimens reported in phase III gastric cancer trials. The results suggest the paclitaxel plus ramucirumab combination is the most effective therapy and should be the reference regimen for future comparative trials.

Fixed ratio combinations of glucagon like peptide 1 receptor agonists with basal insulin: a systematic review and meta-analysis.

Science.gov (United States)

Liakopoulou, Paraskevi; Liakos, Aris; Vasilakou, Despoina; Athanasiadou, Eleni; Bekiari, Eleni; Kazakos, Kyriakos; Tsapas, Apostolos

2017-06-01

Basal insulin controls primarily fasting plasma glucose but causes hypoglycaemia and weight gain, whilst glucagon like peptide 1 receptor agonists induce weight loss without increasing risk for hypoglycaemia. We conducted a systematic review and meta-analysis of randomised controlled trials to investigate the efficacy and safety of fixed ratio combinations of basal insulin with glucagon like peptide 1 receptor agonists. We searched Medline, Embase, and the Cochrane Library as well as conference abstracts up to December 2016. We assessed change in haemoglobin A 1c , body weight, and incidence of hypoglycaemia and gastrointestinal adverse events. We included eight studies with 5732 participants in the systematic review. Switch from basal insulin to fixed ratio combinations with a glucagon like peptide 1 receptor agonist was associated with 0.72% reduction in haemoglobin A 1c [95% confidence interval -1.03 to -0.41; I 2  = 93%] and 2.35 kg reduction in body weight (95% confidence interval -3.52 to -1.19; I 2  = 93%), reducing also risk for hypoglycaemia [odds ratio 0.70; 95% confidence interval 0.57 to 0.86; I 2  = 85%] but increasing incidence of nausea (odds ratio 6.89; 95% confidence interval 3.73-12.74; I 2  = 79%). Similarly, switching patients from treatment with a glucagon like peptide 1 receptor agonist to a fixed ratio combination with basal insulin was associated with 0.94% reduction in haemoglobin A 1c (95% confidence interval -1.11 to -0.77) and an increase in body weight by 2.89 kg (95% confidence interval 2.17-3.61). Fixed ratio combinations of basal insulin with glucagon like peptide 1 receptor agonists improve glycaemic control whilst balancing out risk for hypoglycaemia and gastrointestinal side effects.

Corticosteroid and antiviral therapy for Bell's palsy: A network meta-analysis

Directory of Open Access Journals (Sweden)

Attia John

2011-01-01

Full Text Available Abstract Background Previous meta-analyses of treatments for Bell's palsy are still inconclusive due to different comparators, insufficient data, and lack of power. We therefore conducted a network meta-analysis combining direct and indirect comparisons for assessing efficacy of steroids and antiviral treatment (AVT at 3 and 6 months. Methods We searched Medline and EMBASE until September 2010 using PubMed and Elsviere search engines. A network meta-analysis was performed to assess disease recovery using a mixed effects hierarchical model. Goodness of fit of the model was assessed, and the pooled odds ratio (OR and 95% confidence interval (CI were estimated. Results Six studies (total n = 1805were eligible and contributed to the network meta-analysis. The pooled ORs for resolution at 3 months were 1.24 (95% CI: 0.79 - 1.94 for Acyclovir plus Prednisolone and 1.02 (95% CI: 0.73 - 1.42 for Valacyclovir plus Prednisolone, versus Prednisolone alone. Either Acyclovir or Valacyclovir singly had significantly lower efficacy than Prednisolone alone, i.e., ORs were 0·44 (95% CI: 0·28 - 0·68 and 0·60 (95% CI: 0·42 - 0·87, respectively. Neither of the antiviral agents was significantly different compared with placebo, with a pooled OR of 1·25 (95% CI: 0·78 - 1·98 for Acyclovir and 0·91 (95% CI: 0·63 - 1·31 for Valacyclovir. Overall, Prednisolone-based treatment increased the chance of recovery 2-fold (95% CI: 1·55 - 2·42 compared to non-Prednisolone-based treatment. To gain 1 extra recovery, 6 and 26 patients need to be treated with Acyclovir and prednisolone compared to placebo and prednisolone alone, respectively. Conclusions Our evidence suggests that the current practice of treating Bell's palsy with AVT plus corticosteroid may lead to slightly higher recovery rates compared to treating with prednisone alone but this does not quite reach statistical significance; prednisone remains the best evidence-based treatment.

Acupuncture in the treatment of tinnitus: a systematic review and meta-analysis.

Science.gov (United States)

Liu, Fenye; Han, Xiuli; Li, Yunfeng; Yu, Shudong

2016-02-01

This study aimed at a systematic review and meta-analysis of all available randomized controlled trials (RCTs) using acupuncture to treat tinnitus. Five electronic databases, in both English and Chinese, were searched. All studies in our review and meta-analysis included parallel RCTs of tinnitus patients which compared subjects receiving acupuncture (or its other forms, such as electroacupuncture) to subjects receiving no treatment, sham treatment, drugs or basic medical therapy. Data from the articles were validated and extracted using a predefined data extraction form. Nearly all of Chinese studies reported positive results, while most of English studies reported negative results. Analysis of the combined data found that the acupuncture treatments seemed to provide some advantages over conventional therapies for tinnitus. It had difference in acupuncture points and sessions between Chinese studies and English studies. Methodological flaws were also found in many of the RCTs, especially in Chinese studies. The results of this review suggest that acupuncture therapy may offer subjective benefit to some tinnitus patients. Acupuncture points and sessions used in Chinese studies may be more appropriate, whereas these studies have many methodological flaws and risk bias, which prevents us making a definitive conclusion.

The Impact of Uncertainty on Investment. A Meta-Analysis

Energy Technology Data Exchange (ETDEWEB)

Koetse, M.J. [Department of Spatial Economics, Vrije Universiteit Amsterdam (Netherlands); De Groot, Henri L.F. [Tinbergen Institute, Amsterdam (Netherlands); Florax, R.J.G.M. [Department of Agricultural Economics, Purdue University, West Lafayette (United States)

2006-07-01

In this paper we perform a meta-analysis on empirical estimates of the impact between investment and uncertainty. Since the outcomes of primary studies are largely incomparable with respect to the magnitude of the effect, our analysis focuses on the direction and statistical significance of the relationship. The standard approach in this situation is to estimate an ordered probit model on a categorical estimate, defined in terms of the direction of the effect. The estimates are transformed into marginal effects, in order to represent the changes in the probability of finding a negative significant, insignificant, and positive significant estimate. Although a meta-analysis generally does not allow for inferences on the correctness of model specifications in primary studies, our results give clear directions for model building in empirical investment research. For example, not including factor prices in investment models may seriously affect the model outcomes. Furthermore, we find that Q models produce more negative significant estimates than other models do, ceteris paribus. The outcome of a study is also affected by the type of data used in a primary study. Although it is clear that meta-analysis cannot always give decisive insights into the explanations for the variation in empirical outcomes, our meta-analysis shows that we can explain to a large extent why empirical estimates of the investment uncertainty relationship differ.

A meta-analysis of cerebrovascular disease and hyperhomocysteinaemia

DEFF Research Database (Denmark)

Nielsen, G M; Tvedegaard, K C; Andersen, Niels Trolle

2000-01-01

Hyperhomocysteinaemia has been identified as a risk factor for stroke and cerebrovascular disease in several studies. To evaluate the evidence we performed a meta-analysis. We found 21 studies searching Medline from 1966-July 1999 using the key words homocysteine, homocystine and cerebrovascular...... was used. The reports on 8 cross-sectional and 4 longitudinal studies gave data on the mean and standard deviations of plasma or serum homocysteine for both cases and controls, and these studies were included in the meta-analysis. The results of the 5 excluded studies all pointed to a positive relationship...

The prevalence of food allergy: A meta-analysis

DEFF Research Database (Denmark)

Rona, Roberto J.; Keil, Thomas; Summers, Colin

2007-01-01

Background: There is uncertainty about the prevalence of food allergy in communities. Objective: To assess the prevalence of food allergy by performing a meta-analysis according to the method of assessment used. Methods: The foods assessed were cow's milk, hen's egg, peanut, fish, shellfish....... The meta-analysis included only original studies. They were stratified by age groups: infant/preschool, school children, and adults. Results: A total of 934 articles were identified, but only 51 were considered appropriate for inclusion. The prevalence of self-reported food allergy was very high compared...

Physical Readiness Training: A Meta-Analysis

National Research Council Canada - National Science Library

Vickers, Jr, Ross R

2007-01-01

.... This meta-analysis of available PRT studies (k = 3) indicated that (a) Fitness gains in the PRT program were equal to the gains in traditional fitness programs, and (b) the injury rate (i.e., hazard ratio...

Tumor markers CA19-9, CA242 and CEA in the diagnosis of pancreatic cancer: a meta-analysis.

Science.gov (United States)

Zhang, Yimin; Yang, Jun; Li, Hongjuan; Wu, Yihua; Zhang, Honghe; Chen, Wenhu

2015-01-01

Pancreatic cancer has the worst prognosis and early detection is crucial for improving patient prognosis. Therefore, we performed a meta-analysis to evaluate and compare the sensitivity and specificity of single test of CA19-9, CA242, and CEA, as well as combination test in pancreatic cancer detection. We searched PubMed, Embase, Medline, and Wanfang databases for studies that evaluated the diagnostic validity of CA19-9, CA242, and CEA between January 1990 and September 2014. Data were analyzed by Meta-Disc and STATA software. A total of 21 studies including 3497 participants, which fulfilled the inclusion criteria were considered for analysis. The pooled sensitivities for CA19-9, CA242, and CEA were 75.4 (95% CI: 73.4-77.4), 67.8 (95% CI: 65.5-70), and 39.5 (95% CI: 37.3-41.7), respectively. The pooled specificities of CA19-9, CA242, and CEA were 77.6 (95% CI: 75.4-79.7), 83 (95% CI: 81-85), and 81.3 (95% CI: 79.3-83.2), respectively. Parallel combination of CA19-9+CA242 has a higher sensitivity (89, 95% CI: 80-95) without impairing the specificity (75, 95% CI: 67-82). Our meta-analysis showed that CA242 and CA19-9 have better performance in the diagnosis of pancreatic cancer than CEA. Furthermore, parallel combination test of CA19-9+CA242 could be of better diagnostic value than individual CA242 or CA19-9 test.

Energy efficiency in Germany - a meta-analysis. Analysis and recommendations

International Nuclear Information System (INIS)

Bauernhansl, Thomas

2014-01-01

The Stuttgart Institute of energy efficiency in production compiled the first meta-analysis ''Energy Efficiency in Germany''.It provides facts and figures on the development atatus and knowledge level of energy efficiency in Germany. The study shows the contribution have been made by individual measures and the potentials which are known, but have not yet been lifted. For this meta-analysis more than 250 items available from research institutions, government departments, professional and industry associations have been identified with the main topic of energy efficiency and evaluated. It provides an overview of the status of development and is an important reference work for industry, associations and politics. [de

Diet influenced tooth erosion prevalence in children and adolescents: Results of a meta-analysis and meta-regression

NARCIS (Netherlands)

Salas, M.M.; Nascimento, G.G.; Vargas-Ferreira, F.; Tarquinio, S.B.; Huysmans, M.C.D.N.J.M.; Demarco, F.F.

2015-01-01

OBJECTIVE: The aim of the present study was to assess the influence of diet in tooth erosion presence in children and adolescents by meta-analysis and meta-regression. DATA: Two reviewers independently performed the selection process and the quality of studies was assessed. SOURCES: Studies

Neurological Soft Signs in Schizophrenia: A Meta-analysis

Science.gov (United States)

Chan, Raymond C. K.; Xu, Ting; Heinrichs, R. Walter; Yu, Yue; Wang, Ya

2010-01-01

Background: Neurological soft signs (NSS) are hypothesized as candidate endophenotypes for schizophrenia, but their prevalence and relations with clinical and demographic data are unknown. The authors undertook a quantification (meta-analysis) of the published literature on NSS in patients with schizophrenia and healthy controls. A systematic search was conducted for published articles reporting NSS and related data using standard measures in schizophrenia and healthy comparison groups. Method: A systematic search was conducted for published articles reporting data on the prevalence of NSS in schizophrenia using standard clinical rating scales and healthy comparison groups. Meta-analyses were performed using the Comprehensive Meta-analysis software package. Effect sizes (Cohen d) indexing the difference between schizophrenic patients and the healthy controls were calculated on the basis of reported statistics. Potential moderator variables evaluated included age of patient samples, level of education, sample sex proportions, medication doses, and negative and positive symptoms. Results: A total of 33 articles met inclusion criteria for the meta-analysis. A large and reliable group difference (Cohen d) indicated that, on average, a majority of patients (73%) perform outside the range of healthy subjects on aggregate NSS measures. Cognitive performance and positive and negative symptoms share 2%–10% of their variance with NSS. Conclusions: NSS occur in a majority of the schizophrenia patient population and are largely distinct from symptomatic and cognitive features of the illness. PMID:19377058

Meta-analysis of five genome-wide association studies identifies multiple new loci associated with testicular germ cell tumor

DEFF Research Database (Denmark)

Wang, Zhaoming; McGlynn, Katherine A.; Rajpert-De Meyts, Ewa

2017-01-01

The international Testicular Cancer Consortium (TECAC) combined five published genome-wide association studies of testicular germ cell tumor (TGCT; 3,558 cases and 13,970 controls) to identify new susceptibility loci. We conducted a fixed-effects meta-analysis, including, to our knowledge, the fi...

GetReal in network meta-analysis : a review of the methodology

NARCIS (Netherlands)

Efthimiou, Orestis; Debray, Thomas P A; van Valkenhoef, Gert; Trelle, Sven; Panayidou, Klea; Moons, Karel G M; Reitsma, Johannes B.; Shang, Aijing; Salanti, Georgia

2016-01-01

Pairwise meta-analysis is an established statistical tool for synthesizing evidence from multiple trials, but it is informative only about the relative efficacy of two specific interventions. The usefulness of pairwise meta-analysis is thus limited in real-life medical practice, where many competing

Network meta-analysis-highly attractive but more methodological research is needed

NARCIS (Netherlands)

Li, Tianjing; Puhan, Milo A.; Vedula, Swaroop S.; Singh, Sonal; Dickersin, Kay; Cameron, Chris; Goodman, Steven N.; Mills, Edward; Musch, David; ter Riet, Gerben; Robinson, Karen; Schmid, Christopher; Song, Fujian; Thorlund, Kristian; Trikalinos, Thomas

2011-01-01

Network meta-analysis, in the context of a systematic review, is a meta-analysis in which multiple treatments (that is, three or more) are being compared using both direct comparisons of interventions within randomized controlled trials and indirect comparisons across trials based on a common

Updated Meta-Analysis of Learner Control within Educational Technology

Science.gov (United States)

Karich, Abbey C.; Burns, Matthew K.; Maki, Kathrin E.

2014-01-01

Giving a student control over their learning has theoretical and intuitive appeal, but its effects are neither powerful nor consistent in the empirical literature base. This meta-analysis updated previous meta-analytic research by Niemiec, Sikorski, and Walberg by studying the overall effectiveness of providing learner control within educational…

Does Orthognathic Surgery Cause or Cure Temporomandibular Disorders? A Systematic Review and Meta-Analysis.

Science.gov (United States)

Al-Moraissi, Essam Ahmed; Wolford, Larry M; Perez, Daniel; Laskin, Daniel M; Ellis, Edward

2017-09-01

There is still controversy about whether orthognathic surgery negatively or positively affects temporomandibular disorders (TMDs). The purpose of this study was to determine whether orthognathic surgery has a beneficial or deleterious effect on pre-existing TMDs. A systematic review and meta-analysis were conducted based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We searched 3 major databases to locate all pertinent articles published from 1980 to March 2016. All subjects in the various studies were stratified a priori into 9 categories based on subdiagnoses of TMDs. The predictor variables were those patients with pre-existing TMDs who underwent orthognathic surgery in various subgroups. The outcome variables were maximal mouth opening and signs and symptoms of a TMD before and after orthognathic surgery based on the type of osteotomy. The meta-analysis was performed using Comprehensive Meta-Analysis software (Biostat, Englewood, NJ). A total of 5,029 patients enrolled in 29 studies were included in this meta-analysis. There was a significant reduction in TMDs in patients with a retrognathic mandible after bilateral sagittal split osteotomy (BSSO) (P = .014), but no significant difference after bimaxillary surgery (BSSO and Le Fort I osteotomy) (P = .336). There was a significant difference in patients with prognathism after isolated BSSO or intraoral vertical ramus osteotomy and after combined BSSO and Le Fort I osteotomy (P = .001), but no significant difference after BSSO (P = .424) or bimaxillary surgery (intraoral vertical ramus osteotomy and Le Fort I osteotomy) (P = .728). Orthognathic surgery caused a decrease in TMD symptoms for many patients who had symptoms before surgery, but it created symptoms in a smaller group of patients who were asymptomatic before surgery. The presence of presurgical TMD symptoms or the type of jaw deformity did not identify which patients' TMDs would improve, remain the

Acupuncture therapy for sudden sensorineural hearing loss: a systematic review and meta-analysis of randomized controlled trials.

Science.gov (United States)

Zhang, Xin-chang; Xu, Xiu-ping; Xu, Wen-tao; Hou, Wen-zhen; Cheng, Ying-ying; Li, Chang-xi; Ni, Guang-xia

2015-01-01

Acupuncture has commonly been used in China, either alone or in combination with Western medicine, to treat sudden sensorineural hearing loss (SSHL). The purpose of this systematic review is to assess the efficacy and safety of acupuncture therapy for patients with SSHL. We searched PubMed, the Cochrane Library, Embase, China National Knowledge Internet (CNKI), Database for Chinese Technical Periodicals (VIP), and Chinese Biomedical literature service system (SinoMed) to collect randomized controlled trials of acupuncture for SSHL published before July 2014. A meta-analysis was conducted according to the Cochrane systematic review method using RevMan 5.2 software. The evidence level for each outcome was assessed using the GRADE methodology. Twelve trials involving 863 patients were included. A meta-analysis showed that the effect of manual acupuncture combined with Western medicine comprehensive treatment (WMCT) was better than WMCT alone (RR 1.33, 95%CI 1.19-1.49) and the same as the effect of electroacupuncture combined with WMCT (RR 1.33, 95%CI 1.19-1.50). One study showed a better effect of electroacupuncture than of WMCT (RR 1.34, 95%CI 1.24-1.45). For mean changes in hearing over all frequencies, the meta-analysis showed a better effect with the combination of acupuncture and WMCT than with WMCT alone (MD 10.85, 95%CI 6.84-14.86). However, the evidence levels for these interventions were low or very low due to a high risk of bias and small sample sizes in the included studies. There was not sufficient evidence showing that acupuncture therapy alone was beneficial for treating SSHL. However, interventions combining acupuncture with WMCT had more efficacious results in the treatment of SSHL than WMCT alone. Electroacupuncture alone might be a viable alternative treatment besides WMCT for SSHL. However, given that there were fewer eligible RCTs and limitations in the included trials, such as methodological drawbacks and small sample sizes, large-scale RCTs are

Acupuncture therapy for sudden sensorineural hearing loss: a systematic review and meta-analysis of randomized controlled trials.

Directory of Open Access Journals (Sweden)

Xin-chang Zhang

Full Text Available Acupuncture has commonly been used in China, either alone or in combination with Western medicine, to treat sudden sensorineural hearing loss (SSHL. The purpose of this systematic review is to assess the efficacy and safety of acupuncture therapy for patients with SSHL.We searched PubMed, the Cochrane Library, Embase, China National Knowledge Internet (CNKI, Database for Chinese Technical Periodicals (VIP, and Chinese Biomedical literature service system (SinoMed to collect randomized controlled trials of acupuncture for SSHL published before July 2014. A meta-analysis was conducted according to the Cochrane systematic review method using RevMan 5.2 software. The evidence level for each outcome was assessed using the GRADE methodology.Twelve trials involving 863 patients were included. A meta-analysis showed that the effect of manual acupuncture combined with Western medicine comprehensive treatment (WMCT was better than WMCT alone (RR 1.33, 95%CI 1.19-1.49 and the same as the effect of electroacupuncture combined with WMCT (RR 1.33, 95%CI 1.19-1.50. One study showed a better effect of electroacupuncture than of WMCT (RR 1.34, 95%CI 1.24-1.45. For mean changes in hearing over all frequencies, the meta-analysis showed a better effect with the combination of acupuncture and WMCT than with WMCT alone (MD 10.85, 95%CI 6.84-14.86. However, the evidence levels for these interventions were low or very low due to a high risk of bias and small sample sizes in the included studies.There was not sufficient evidence showing that acupuncture therapy alone was beneficial for treating SSHL. However, interventions combining acupuncture with WMCT had more efficacious results in the treatment of SSHL than WMCT alone. Electroacupuncture alone might be a viable alternative treatment besides WMCT for SSHL. However, given that there were fewer eligible RCTs and limitations in the included trials, such as methodological drawbacks and small sample sizes, large

A systematic review and meta-analysis of the circulatory, erythrocellular and CSF selenium levels in Alzheimer's disease: A metal meta-analysis (AMMA study-I).

Science.gov (United States)

Reddy, Varikasuvu Seshadri; Bukke, Suman; Dutt, Naveen; Rana, Puneet; Pandey, Arun Kumar

2017-07-01

Available studies in the literature on the selenium levels in Alzheimer's disease (AD) are inconsistent with some studies reporting its decrease in the circulation, while others reported an increase or no change as compared to controls. The objective of this study was to perform a meta-analysis of circulatory (plasma/serum and blood), erythrocyte and cerebrospinal fluid (CSF) selenium levels in AD compared controls. We also performed a meta-analysis of the correlation coefficients (r) to demonstrate the associations between selenium and glutathione peroxidase (GPx) in AD patients. All major databases were searched for eligible studies. We included 12 case-control/observational studies reporting selenium concentrations in AD and controls. Pooled-overall effect size as standardized mean difference (SMD) and pooled r-values were generated using Review Manager 5.3 and MedCalc 15.8 software. Random-effects meta-analysis indicated a decrease in circulatory (SMD=-0.44), erythrocellular (SMD=-0.52) and CSF (SMD=-0.14) selenium levels in AD patients compared to controls. Stratified meta-analysis demonstrated that the selenium levels were decreased in both the subgroups with (SMD=-0.55) and without (SMD=-0.37) age matching between AD and controls. Our results also demonstrated a direct association between decreased selenium levels and GPx in AD. This meta-analysis suggests that circulatory selenium concentration is significantly lower in AD patients compared to controls and this decrease in selenium is directly correlated with an important antioxidant enzyme, the GPx, in AD. Copyright © 2017 Elsevier GmbH. All rights reserved.

Manual therapy, exercise therapy or combined treatment in the management of adult neck pain - A systematic review and meta-analysis.

Science.gov (United States)

Fredin, Ken; Lorås, Håvard

2017-10-01

Neck pain is a common and often disabling musculoskeletal condition. Two therapies frequently prescribed for its management are manual therapy (MT) and exercise therapy (ET), and combining these treatment approaches are common. To assess whether or not combined treatment consisting of MT and ET is more effective than either therapy alone in relieving pain and improving function in adult patients with grade I-II neck pain. Systematic review with meta-analysis. A systematic search on EMBASE, MEDLINE, AMED, CENTRAL and PEDro were performed until June 2017. Randomized controlled trials with adult grade I-II neck pain patients were included if they investigated the combined effect of MT and ET to the same ET or MT alone, and reported pain intensity or disability on numerical scales. Quality of life was assessed as a secondary outcome. Quality of the included trials was assessed with the PEDro scale, and the quality of evidence was assessed with GRADE. 1169 articles were screened, and 7 studies were included, all of which investigated the addition of ET to MT. Only very small and non-significant between group differences was found on pain intensity at rest, neck disability, and quality of life at immediate post-treatment, 6 months, and 12 months follow-up. The quality of evidence was moderate for pain-at-rest outcomes and moderate too low for neck disability and quality of life outcomes. Combined treatment consisting of MT and ET does not seem to be more effective in reducing neck pain intensity at rest, neck disability or improving quality of life in adult patients with grade I-II neck pain, than ET alone. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparison of palbociclib in combination with letrozole or fulvestrant with endocrine therapies for advanced/metastatic breast cancer: network meta-analysis.

Science.gov (United States)

Chirila, Costel; Mitra, Debanjali; Colosia, Ann; Ling, Caroline; Odom, Dawn; Iyer, Shrividya; Kaye, James A

2017-08-01

Palbociclib is the first cyclin-dependent kinase 4/6 inhibitor approved in the United States for HR+/HER2- advanced/metastatic breast cancer, in combination with letrozole as initial endocrine-based therapy in postmenopausal women or with fulvestrant in women with disease progression following endocrine therapy. We compared progression-free survival (PFS) and discontinuations due to adverse events for palbociclib combinations against other endocrine therapies using a mixed-treatment comparison meta-analysis of randomized, controlled trials. A systematic literature review identified relevant trials. Separate analyses were conducted for each palbociclib combination using a Bayesian approach. Treatment rankings were established using the surface under the cumulative ranking curve (SUCRA). Sixty-five unique studies met inclusion criteria. Palbociclib plus letrozole had the highest SUCRA value (99.9%) and was associated with significantly longer PFS than all comparators in treatment-naïve patients (hazard ratios [HRs] ranged from 0.41 to 0.58). Palbociclib plus fulvestrant had the second highest SUCRA value (93.9%) and, in previously treated patients, yielded significantly longer PFS than most comparators (HRs ranged from 0.26 to 0.46); the exception was everolimus plus exemestane, with similar PFS (HR, 1.04; 95% credible interval [CrI], 0.58-1.76). Palbociclib plus fulvestrant was associated with significantly lower odds of discontinuation due to adverse events than everolimus plus exemestane (odds ratio, 0.14; 95% CrI, 0.05-0.39). The results suggest that the two palbociclib combinations yielded significantly greater PFS than endocrine therapy in treatment-naïve and previously treated patients with advanced/metastatic breast cancer. Palbociclib plus fulvestrant was associated with significantly less toxicity than everolimus plus exemestane.

A genome-wide association meta-analysis identifies new childhood obesity loci

Science.gov (United States)

Bradfield, Jonathan P.; Taal, H. Rob; Timpson, Nicholas J.; Scherag, André; Lecoeur, Cecile; Warrington, Nicole M.; Hypponen, Elina; Holst, Claus; Valcarcel, Beatriz; Thiering, Elisabeth; Salem, Rany M.; Schumacher, Fredrick R.; Cousminer, Diana L.; Sleiman, Patrick M.A.; Zhao, Jianhua; Berkowitz, Robert I.; Vimaleswaran, Karani S.; Jarick, Ivonne; Pennell, Craig E.; Evans, David M.; St. Pourcain, Beate; Berry, Diane J.; Mook-Kanamori, Dennis O; Hofman, Albert; Rivadeinera, Fernando; Uitterlinden, André G.; van Duijn, Cornelia M.; van der Valk, Ralf J.P.; de Jongste, Johan C.; Postma, Dirkje S.; Boomsma, Dorret I.; Gauderman, William J.; Hassanein, Mohamed T.; Lindgren, Cecilia M.; Mägi, Reedik; Boreham, Colin A.G.; Neville, Charlotte E.; Moreno, Luis A.; Elliott, Paul; Pouta, Anneli; Hartikainen, Anna-Liisa; Li, Mingyao; Raitakari, Olli; Lehtimäki, Terho; Eriksson, Johan G.; Palotie, Aarno; Dallongeville, Jean; Das, Shikta; Deloukas, Panos; McMahon, George; Ring, Susan M.; Kemp, John P.; Buxton, Jessica L.; Blakemore, Alexandra I.F.; Bustamante, Mariona; Guxens, Mònica; Hirschhorn, Joel N.; Gillman, Matthew W.; Kreiner-Møller, Eskil; Bisgaard, Hans; Gilliland, Frank D.; Heinrich, Joachim; Wheeler, Eleanor; Barroso, Inês; O'Rahilly, Stephen; Meirhaeghe, Aline; Sørensen, Thorkild I.A.; Power, Chris; Palmer, Lyle J.; Hinney, Anke; Widen, Elisabeth; Farooqi, I. Sadaf; McCarthy, Mark I.; Froguel, Philippe; Meyre, David; Hebebrand, Johannes; Jarvelin, Marjo-Riitta; Jaddoe, Vincent W.V.; Smith, George Davey; Hakonarson, Hakon; Grant, Struan F.A.

2012-01-01

Multiple genetic variants have been associated with adult obesity and a few with severe obesity in childhood; however, less progress has been made to establish genetic influences on common early-onset obesity. We performed a North American-Australian-European collaborative meta-analysis of fourteen studies consisting of 5,530 cases (≥95th percentile of body mass index (BMI)) and 8,318 controls (<50th percentile of BMI) of European ancestry. Taking forward the eight novel signals yielding association with P < 5×10−6 in to nine independent datasets (n = 2,818 cases and 4,083 controls) we observed two loci that yielded a genome wide significant combined P-value, namely near OLFM4 on 13q14 (rs9568856; P=1.82×10−9; OR=1.22) and within HOXB5 on 17q21 (rs9299; P=3.54×10−9; OR=1.14). Both loci continued to show association when including two extreme childhood obesity cohorts (n = 2,214 cases and 2,674 controls). Finally, these two loci yielded directionally consistent associations in the GIANT meta-analysis of adult BMI1. PMID:22484627

ALE Meta-Analysis of Schizophrenics Performing the N-Back Task

Science.gov (United States)

Harrell, Zachary

2010-10-01

MRI/fMRI has already proven itself as a valuable tool in the diagnosis and treatment of many illnesses of the brain, including cognitive problems. By exploiting the differences in magnetic susceptibility between oxygenated and deoxygenated hemoglobin, fMRI can measure blood flow in various regions of interest within the brain. This can determine the level of brain activity in relation to motor or cognitive functions and provide a metric for tissue damage or illness symptoms. Structural imaging techniques have shown lesions or deficiencies in tissue volumes in schizophrenics corresponding to areas primarily in the frontal and temporal lobes. These areas are currently known to be involved in working memory and attention, which many schizophrenics have trouble with. The ALE (Activation Likelihood Estimation) Meta-Analysis is able to statistically determine the significance of brain area activations based on the post-hoc combination of multiple studies. This process is useful for giving a general model of brain function in relation to a particular task designed to engage the affected areas (such as working memory for the n-back task). The advantages of the ALE Meta-Analysis include elimination of single subject anomalies, elimination of false/extremely weak activations, and verification of function/location hypotheses.

A meta-frontier approach for causal inference in productivity analysis

DEFF Research Database (Denmark)

Henningsen, Arne; Mpeta, Daniel F.; Adem, Anwar S.

(2012) and create a meta-frontier in order to estimate the effects of participation on the farms’ meta-technology ratio, their group technical efficiency, and their meta-technology technical efficiency. The empirical analysis uses a cross-sectional data set from sunflower farmers in Tanzania, where some...... by the contractor’s provision of (additional) extension service and seeds of high-yielding varieties to the contract farmers....

Radiosurgery of Glomus Jugulare Tumors: A Meta-Analysis

International Nuclear Information System (INIS)

Guss, Zachary D.; Batra, Sachin; Limb, Charles J.; Li, Gordon; Sughrue, Michael E.; Redmond, Kristin; Rigamonti, Daniele; Parsa, Andrew T.; Chang, Steven; Kleinberg, Lawrence; Lim, Michael

2011-01-01

Purpose: During the past two decades, radiosurgery has arisen as a promising approach to the management of glomus jugulare. In the present study, we report on a systematic review and meta-analysis of the available published data on the radiosurgical management of glomus jugulare tumors. Methods and Materials: To identify eligible studies, systematic searches of all glomus jugulare tumors treated with radiosurgery were conducted in major scientific publication databases. The data search yielded 19 studies, which were included in the meta-analysis. The data from 335 glomus jugulare patients were extracted. The fixed effects pooled proportions were calculated from the data when Cochrane's statistic was statistically insignificant and the inconsistency among studies was 36 months. In these studies, 95% of patients achieved clinical control and 96% achieved tumor control. The gamma knife, linear accelerator, and CyberKnife technologies all exhibited high rates of tumor and clinical control. Conclusions: The present study reports the results of a meta-analysis for the radiosurgical management of glomus jugulare. Because of its high effectiveness, we suggest considering radiosurgery for the primary management of glomus jugulare tumors.

Meta-analysis in applied ecology.

Science.gov (United States)

Stewart, Gavin

2010-02-23

This overview examines research synthesis in applied ecology and conservation. Vote counting and pooling unweighted averages are widespread despite the superiority of syntheses based on weighted combination of effects. Such analyses allow exploration of methodological uncertainty in addition to consistency of effects across species, space and time, but exploring heterogeneity remains controversial. Meta-analyses are required to generalize in ecology, and to inform evidence-based decision-making, but the more sophisticated statistical techniques and registers of research used in other disciplines must be employed in ecology to fully realize their benefits.

A meta-analysis of serious digital games for healthy lifestyle promotion

Science.gov (United States)

Several systematic reviews have described health-promoting effects of serious games, but so far no meta-analysis has been reported. This paper presents a meta-analysis of 54 serious digital game studies for healthy lifestyle promotion, in which we investigated the overall effectiveness of serious di...

Ranibizumab alone or in combination with photodynamic therapy vs photodynamic therapy for polypoidal choroidal vasculopathy: a systematic review and Meta-analysis.

Science.gov (United States)

Tang, Kai; Si, Jun-Kang; Guo, Da-Dong; Cui, Yan; Du, Yu-Xiang; Pan, Xue-Mei; Bi, Hong-Sheng

2015-01-01

To compare the efficacy of intravitreal ranibizumab (IVR) alone or in combination with photodynamic therapy (PDT) vs PDT in patients with symptomatic polypoidal choroidal vasculopathy (PCV). A systematic search of a wide range of databases (including PubMed, EMBASE, Cochrane Library and Web of Science) was searched to identify relevant studies. Both randomized controlled trials (RCTs) and non-RCT studies were included. Methodological quality of included literatures was evaluated according to the Newcastle-Ottawa Scale. RevMan 5.2.7 software was used to do the Meta-analysis. Three RCTs and 6 retrospective studies were included. The results showed that PDT monotherapy had a significantly higher proportion in patients who achieved complete regression of polyps than IVR monotherapy at months 3, 6, and 12 (All P≤0.01), respectively. However, IVR had a tendency to be more effective in improving vision on the basis of RCTs. The proportion of patients who gained complete regression of polyps revealed that there was no significant difference between the combination treatment and PDT monotherapy. The mean change of best-corrected visual acuity (BCVA) from baseline showed that the combination treatment had significant superiority in improving vision vs PDT monotherapy at months 3, 6 and 24 (All Pcompare with PDT either in stabilizing or in improving vision, although it can hardly promote the regression of polyps. The combination treatment of PDT and IVR can exert a synergistic effect on regressing polyps and on maintaining or improving visual acuity. Thus, it can be the first-line therapy for PCV.

Fatal flaws in a recent meta-analysis on abortion and mental health.

Science.gov (United States)

Steinberg, Julia R; Trussell, James; Hall, Kelli S; Guthrie, Kate

2012-11-01

Similar to other reviews within the last 4 years, a thorough review by the Royal College of Psychiatrists, published in December 2011, found that compared to delivery of an unintended pregnancy, abortion does not increase women's risk of mental health problems. In contrast, a meta-analysis published in September 2011 concluded that abortion increases women's risk of mental health problems by 81% and that 10% of mental health problems are attributable to abortions. Like others, we strongly question the quality of this meta-analysis and its conclusions. Here we detail seven errors of this meta-analysis and three significant shortcomings of the included studies because policy, practice and the public have been misinformed. These errors and shortcomings render the meta-analysis' conclusions invalid. Copyright © 2012 Elsevier Inc. All rights reserved.

Prevalence of gestational diabetes mellitus in Europe: A meta-analysis.

Science.gov (United States)

Eades, Claire E; Cameron, Dawn M; Evans, Josie M M

2017-07-01

Estimates of the prevalence of gestational diabetes vary widely. It is important to have a clear understanding of the prevalence of this condition to be able to plan interventions and health care provision. This paper describes a meta-analysis of primary research data reporting the prevalence of gestational diabetes mellitus in the general pregnant population of developed countries in Europe. Four electronic databases were systematically searched in May 2016. English language articles reporting gestational diabetes mellitus prevalence using universal screening in general pregnant population samples from developed countries in Europe were included. All papers identified by the search were screened by one author, and then half screened independently by a second author and half by a third author. Data were extracted by one author. Values for the measures of interest were combined using a random effects model and analysis of the effects of moderator variables was carried out. A total of 3258 abstracts were screened, with 40 studies included in the review. Overall prevalence of gestational diabetes mellitus was 5.4% (3.8-7.8). Maternal age, year of data collection, country, area of Europe, week of gestation at testing, and diagnostic criteria were found to have a significant univariate effect on GDM prevalence, and area, week of gestation at testing and year of data collection remained statistically significant in multivariate analysis. Quality category was significant in multivariate but not univariate analysis. This meta-analysis shows prevalence of GDM that is at the upper end of previous estimates in Europe. Copyright © 2017 Elsevier B.V. All rights reserved.

Meta-analysis of 74,046 individuals identifies 11 new susceptibility loci for Alzheimer’s disease

Science.gov (United States)

Lambert, Jean-Charles; Ibrahim-Verbaas, Carla A; Harold, Denise; Naj, Adam C; Sims, Rebecca; Bellenguez, Céline; Jun, Gyungah; DeStefano, Anita L; Bis, Joshua C; Beecham, Gary W; Grenier-Boley, Benjamin; Russo, Giancarlo; Thornton-Wells, Tricia A; Jones, Nicola; Smith, Albert V; Chouraki, Vincent; Thomas, Charlene; Ikram, M Arfan; Zelenika, Diana; Vardarajan, Badri N; Kamatani, Yoichiro; Lin, Chiao-Feng; Gerrish, Amy; Schmidt, Helena; Kunkle, Brian; Dunstan, Melanie L; Ruiz, Agustin; Bihoreau, Marie-Thérèse; Choi, Seung-Hoan; Reitz, Christiane; Pasquier, Florence; Hollingworth, Paul; Ramirez, Alfredo; Hanon, Olivier; Fitzpatrick, Annette L; Buxbaum, Joseph D; Campion, Dominique; Crane, Paul K; Baldwin, Clinton; Becker, Tim; Gudnason, Vilmundur; Cruchaga, Carlos; Craig, David; Amin, Najaf; Berr, Claudine; Lopez, Oscar L; De Jager, Philip L; Deramecourt, Vincent; Johnston, Janet A; Evans, Denis; Lovestone, Simon; Letenneur, Luc; Morón, Francisco J; Rubinsztein, David C; Eiriksdottir, Gudny; Sleegers, Kristel; Goate, Alison M; Fiévet, Nathalie; Huentelman, Matthew J; Gill, Michael; Brown, Kristelle; Kamboh, M Ilyas; Keller, Lina; Barberger-Gateau, Pascale; McGuinness, Bernadette; Larson, Eric B; Green, Robert; Myers, Amanda J; Dufouil, Carole; Todd, Stephen; Wallon, David; Love, Seth; Rogaeva, Ekaterina; Gallacher, John; St George-Hyslop, Peter; Clarimon, Jordi; Lleo, Alberto; Bayer, Anthony; Tsuang, Debby W; Yu, Lei; Tsolaki, Magda; Bossù, Paola; Spalletta, Gianfranco; Proitsi, Petroula; Collinge, John; Sorbi, Sandro; Sanchez-Garcia, Florentino; Fox, Nick C; Hardy, John; Deniz Naranjo, Maria Candida; Bosco, Paolo; Clarke, Robert; Brayne, Carol; Galimberti, Daniela; Mancuso, Michelangelo; Matthews, Fiona; Moebus, Susanne; Mecocci, Patrizia; Zompo, Maria Del; Maier, Wolfgang; Hampel, Harald; Pilotto, Alberto; Bullido, Maria; Panza, Francesco; Caffarra, Paolo; Nacmias, Benedetta; Gilbert, John R; Mayhaus, Manuel; Lannfelt, Lars; Hakonarson, Hakon; Pichler, Sabrina; Carrasquillo, Minerva M; Ingelsson, Martin; Beekly, Duane; Alvarez, Victoria; Zou, Fanggeng; Valladares, Otto; Younkin, Steven G; Coto, Eliecer; Hamilton-Nelson, Kara L; Gu, Wei; Razquin, Cristina; Pastor, Pau; Mateo, Ignacio; Owen, Michael J; Faber, Kelley M; Jonsson, Palmi V; Combarros, Onofre; O’Donovan, Michael C; Cantwell, Laura B; Soininen, Hilkka; Blacker, Deborah; Mead, Simon; Mosley, Thomas H; Bennett, David A; Harris, Tamara B; Fratiglioni, Laura; Holmes, Clive; de Bruijn, Renee F A G; Passmore, Peter; Montine, Thomas J; Bettens, Karolien; Rotter, Jerome I; Brice, Alexis; Morgan, Kevin; Foroud, Tatiana M; Kukull, Walter A; Hannequin, Didier; Powell, John F; Nalls, Michael A; Ritchie, Karen; Lunetta, Kathryn L; Kauwe, John S K; Boerwinkle, Eric; Riemenschneider, Matthias; Boada, Mercè; Hiltunen, Mikko; Martin, Eden R; Schmidt, Reinhold; Rujescu, Dan; Wang, Li-san; Dartigues, Jean-François; Mayeux, Richard; Tzourio, Christophe; Hofman, Albert; Nöthen, Markus M; Graff, Caroline; Psaty, Bruce M; Jones, Lesley; Haines, Jonathan L; Holmans, Peter A; Lathrop, Mark; Pericak-Vance, Margaret A; Launer, Lenore J; Farrer, Lindsay A; van Duijn, Cornelia M; Van Broeckhoven, Christine; Moskvina, Valentina; Seshadri, Sudha; Williams, Julie; Schellenberg, Gerard D; Amouyel, Philippe

2013-01-01

Eleven susceptibility loci for late-onset Alzheimer’s disease (LOAD) were identified by previous studies; however, a large portion of the genetic risk for this disease remains unexplained. We conducted a large, two-stage meta-analysis of genome-wide association studies (GWAS) in individuals of European ancestry. In stage 1, we used genotyped and imputed data (7,055,881 SNPs) to perform meta-analysis on 4 previously published GWAS data sets consisting of 17,008 Alzheimer’s disease cases and 37,154 controls. In stage 2,11,632 SNPs were genotyped and tested for association in an independent set of 8,572 Alzheimer’s disease cases and 11,312 controls. In addition to the APOE locus (encoding apolipoprotein E), 19 loci reached genome-wide significance (P < 5 × 10−8) in the combined stage 1 and stage 2 analysis, of which 11 are newly associated with Alzheimer’s disease. PMID:24162737

The Neural Correlates of Moral Thinking: A Meta-Analysis

OpenAIRE

Douglas J. Bryant; Wang F; Kelley Deardeuff; Emily Zoccoli; Chang S. Nam

2016-01-01

We conducted a meta-analysis to evaluate current research that aims to map the neural correlates of two typical conditions of moral judgment: right-wrong moral judgments and decision-making in moral dilemmas. Utilizing the activation likelihood estimation (ALE) method, we conducted a meta-analysis using neuroimaging data obtained from twenty-one previous studies that measured responses in one or the other of these conditions. We found that across the studies (n = 400), distinct neural circuit...

Meta-analysis: Nitroglycerin for prevention of post-ERCP pancreatitis

DEFF Research Database (Denmark)

Nøjgaard, C; Matzen, P; Andersen, Per Kragh

2009-01-01

BACKGROUND: Acute pancreatitis after ERCP is a severe side effect. AIM: To evaluate the preventive effect of nitroglycerin on post-ERCP pancreatitis by a meta-analysis of randomized clinical studies. METHODS: We searched on Pubmed, Embase, Cochrane Library and all abstracts presented at Digestive......-ERCP pancreatitis after administration of nitroglycerin were identified. Meta-analysis including all five studies showed a relative risk (RR) of 0.61 (95% CI; 0.44, 0.86) with the number needed to treat (NNT) of 26 (95% CI: 16, 82). Three studies evaluated nitroglycerin administered by a dermal patch reaching...... together an RR of 0.66 (95% CI; 0.43, 1.01). The use of nitroglycerin is associated with a significantly increased risk of hypotension (RR 2.25) and headache (RR 3.64). No difference in mortality was observed. CONCLUSIONS: Overall, our meta-analysis supports the use of nitroglycerin in the prevention...

Role of Esophageal Metal Stents Placement and Combination Therapy in Inoperable Esophageal Carcinoma: A Systematic Review and Meta-analysis.

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Lai, Andrew; Lipka, Seth; Kumar, Ambuj; Sethi, Sajiv; Bromberg, David; Li, Nanxing; Shen, Huafeng; Stefaniwsky, Lilia; Brady, Patrick

2018-04-01

More than 50% of patients with esophageal cancer already have inoperable disease at the time of diagnosis. Controversy surrounds the outcomes of patients with advanced esophageal cancer who receive palliative care by either stent alone or stent plus an additional modality. We set out to perform a systematic review and meta-analysis of studies assessing the use of metal stents as treatment options for symptomatic improvement, survival, and adverse events. We searched Embase, MEDLINE, and the Cochrane Central Register of Controlled Trials (CENTRAL) from inception until January 14, 2016, as well as other databases for randomized controlled trials (RCTs) comparing esophageal stent versus either esophageal stent plus brachytherapy, radiotherapy, or chemotherapy. For quality assurance purposes throughout the systematic review, multiple independent extractions were performed, and the process was executed as per the standards of the Cochrane collaboration. Primary outcomes were mean change in dysphagia score, overall survival, and quality of life. Secondary outcomes were adverse events including fever, severe pain, aspiration, fistula, stent migration, perforation, and restenosis. Eight RCTs enrolling 732 patients were included with three distinct comparisons: stents combination therapy vs stents alone (5 studies, n = 417), stents alone versus brachytherapy alone (2 studies, n = 274), and stents + brachytherapy vs brachytherapy alone (1 study, n = 41). Stents combination therapy was defined as stents plus radiotherapy, chemotherapy, or both. Mean change in dysphagia scores favored stents combination therapy versus stents alone, and the effect was seen in patients surviving longer than 3 months. Stents combination therapy was also associated with a more favorable overall survival. The risks of stent migration, aspiration pneumonia, and restenosis were lower in the stents combination group compared to stents alone, while the risks of severe pain, hemorrhage, and

A Meta-Analysis of Typhoid Diagnostic Accuracy Studies: A Recommendation to Adopt a Standardized Composite Reference.

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Helen L Storey

Full Text Available Novel typhoid diagnostics currently under development have the potential to improve clinical care, surveillance, and the disease burden estimates that support vaccine introduction. Blood culture is most often used as the reference method to evaluate the accuracy of new typhoid tests; however, it is recognized to be an imperfect gold standard. If no single gold standard test exists, use of a composite reference standard (CRS can improve estimation of diagnostic accuracy. Numerous studies have used a CRS to evaluate new typhoid diagnostics; however, there is no consensus on an appropriate CRS. In order to evaluate existing tests for use as a reference test or inclusion in a CRS, we performed a systematic review of the typhoid literature to include all index/reference test combinations observed. We described the landscape of comparisons performed, showed results of a meta-analysis on the accuracy of the more common combinations, and evaluated sources of variability based on study quality. This wide-ranging meta-analysis suggests that no single test has sufficiently good performance but some existing diagnostics may be useful as part of a CRS. Additionally, based on findings from the meta-analysis and a constructed numerical example demonstrating the use of CRS, we proposed necessary criteria and potential components of a typhoid CRS to guide future recommendations. Agreement and adoption by all investigators of a standardized CRS is requisite, and would improve comparison of new diagnostics across independent studies, leading to the identification of a better reference test and improved confidence in prevalence estimates.

A Healthy Dietary Pattern Reduces Lung Cancer Risk: A Systematic Review and Meta-Analysis.

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Sun, Yanlai; Li, Zhenxiang; Li, Jianning; Li, Zengjun; Han, Jianjun

2016-03-04

Diet and nutrients play an important role in cancer development and progress; a healthy dietary pattern has been found to be associated with several types of cancer. However, the association between a healthy eating pattern and lung cancer risk is still unclear. Therefore, we conducted a systematic review with meta-analysis to evaluate whether a healthy eating pattern might reduce lung cancer risk. We identified relevant studies from the PubMed and Embase databases up to October 2015, and the relative risks were extracted and combined by the fixed-effects model when no substantial heterogeneity was observed; otherwise, the random-effects model was employed. Subgroup and publication bias analyses were also performed. Finally, eight observational studies were included in the meta-analysis. The pooled relative risk of lung cancer for the highest vs. lowest category of healthy dietary pattern was 0.81 (95% confidence interval, CI: 0.75-0.86), and no significant heterogeneity was detected. The relative risks (RRs) for non-smokers, former smokers and current smokers were 0.89 (95% CI: 0.63-1.27), 0.74 (95% CI: 0.62-0.89) and 0.86 (95% CI: 0.79-0.93), respectively. The results remained stable in subgroup analyses by other confounders and sensitivity analysis. The results of our meta-analysis suggest that a healthy dietary pattern is associated with a lower lung cancer risk, and they provide more beneficial evidence for changing the diet pattern in the general population.

Meta-connectomics: human brain network and connectivity meta-analyses.

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Crossley, N A; Fox, P T; Bullmore, E T

2016-04-01

Abnormal brain connectivity or network dysfunction has been suggested as a paradigm to understand several psychiatric disorders. We here review the use of novel meta-analytic approaches in neuroscience that go beyond a summary description of existing results by applying network analysis methods to previously published studies and/or publicly accessible databases. We define this strategy of combining connectivity with other brain characteristics as 'meta-connectomics'. For example, we show how network analysis of task-based neuroimaging studies has been used to infer functional co-activation from primary data on regional activations. This approach has been able to relate cognition to functional network topology, demonstrating that the brain is composed of cognitively specialized functional subnetworks or modules, linked by a rich club of cognitively generalized regions that mediate many inter-modular connections. Another major application of meta-connectomics has been efforts to link meta-analytic maps of disorder-related abnormalities or MRI 'lesions' to the complex topology of the normative connectome. This work has highlighted the general importance of network hubs as hotspots for concentration of cortical grey-matter deficits in schizophrenia, Alzheimer's disease and other disorders. Finally, we show how by incorporating cellular and transcriptional data on individual nodes with network models of the connectome, studies have begun to elucidate the microscopic mechanisms underpinning the macroscopic organization of whole-brain networks. We argue that meta-connectomics is an exciting field, providing robust and integrative insights into brain organization that will likely play an important future role in consolidating network models of psychiatric disorders.

Quality of life in autism across the lifespan: A meta-analysis

NARCIS (Netherlands)

van Heijst, B.F.C.; Geurts, H.M.

2015-01-01

Autism is a lifelong neurodevelopmental disorder, with a known impact on quality of life. Yet the developmental trajectory of quality of life is not well understood. First, the effect of age on quality of life was studied with a meta-analysis. Our meta-analysis included 10 studies (published between

Child-Centered Play Therapy in the Schools: Review and Meta-Analysis

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Ray, Dee C.; Armstrong, Stephen A.; Balkin, Richard S.; Jayne, Kimberly M.

2015-01-01

The authors conducted a meta-analysis and systematic review that examined 23 studies evaluating the effectiveness of child centered play therapy (CCPT) conducted in elementary schools. Meta-analysis results were explored using a random effects model for mean difference and mean gain effect size estimates. Results revealed statistically significant…

Triple therapy in type 2 diabetes; a systematic review and network meta-analysis

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Martin J. Downes

2015-12-01

Full Text Available Aims. The purpose was to evaluate the evidence for triple therapy regimen using medicines available in Australia for type 2 diabetes.Methods. A systematic literature review was performed to update the relevant evidence from 2002 to 2014 on triple therapy for type 2 diabetes. A multiple-treatments network meta-analysis was undertaken to summarise the comparative efficacy and harms of different triple therapies.Results. Twenty seven trials were identified, most were six months of duration. The following combinations were included in the network meta-analysis: metformin (MET + sulfonylureas (SU (used as reference combination; MET + SU+ dipeptidyl peptidase 4 inhibitors (DPP-4-i; MET + SU+ thiazolidinediones (TZD; MET + SU+ glucagon-like peptide-1 receptor agonists (GLP-1-RA; MET + SU+ insulins; MET + TZD + DPP-4-i; and MET + SU+ sodium/glucose cotransporter 2 inhibitors (SGLT2-i. For HbA1c reduction, all triple therapies were statistically superior to MET+SU dual therapy, except for MET + TZD + DPP-4-i. None of the triple therapy combinations demonstrated differences in HbA1c compared with other triple therapies. MET + SU + SGLT2-i and MET + SU + GLP-1-RA resulted in significantly lower body weight than MET + SU + DPP-4-i, MET+SU+insulin and MET + SU + TZDs; MET + SU + DPP-4-i resulted in significantly lower body weight than MET + SU + insulin and MET + SU + TZD. MET + SU + insulin, MET + SU + TZD and MET + SU + DPP-4-i increased the odds of hypoglycaemia when compared to MET + SU. MET + SU + GLP-1-RA reduced the odds of hypoglycaemia compared to MET + SU + insulin.Conclusion. Care when choosing a triple therapy combination is needed as there is often a risk of increased hypoglycaemia events associated with this regimen and there are very limited data surrounding the long-term effectiveness and safety of combined therapies.

Systematic review and meta-analysis of in vitro synergy of polymyxins and carbapenems.

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Zusman, Oren; Avni, Tomer; Leibovici, Leonard; Adler, Amos; Friberg, Lena; Stergiopoulou, Theodouli; Carmeli, Yehuda; Paul, Mical

2013-10-01

Our objective was to examine the evidence of in vitro synergy of polymyxin-carbapenem combination therapy against Gram-negative bacteria (GNB). A systematic review and meta-analysis were performed. All studies examining in vitro interactions of antibiotic combinations consisting of any carbapenem with colistin or polymyxin B against any GNB were used. A broad search was conducted with no language, date, or publication status restrictions. Synergy rates, defined as a fractional inhibitory concentration index of ≤0.5 or a >2-log reduction in CFU, were pooled separately for time-kill, checkerboard, and Etest methods in a mixed-effect meta-analysis of rates. We examined whether the synergy rate depended on the testing method, type of antibiotic, bacteria, and resistance to carbapenems. Pooled rates with 95% confidence intervals (CI) are shown. Thirty-nine published studies and 15 conference proceeding were included, reporting on 246 different tests on 1,054 bacterial isolates. In time-kill studies, combination therapy showed synergy rates of 77% (95% CI, 64 to 87%) for Acinetobacter baumannii, 44% (95% CI, 30 to 59%) for Klebsiella pneumoniae, and 50% (95% CI, 30 to 69%) for Pseudomonas aeruginosa, with low antagonism rates for all. Doripenem showed high synergy rates for all three bacteria. For A. baumannii, meropenem was more synergistic than imipenem, whereas for P. aeruginosa the opposite was true. Checkerboard and Etest studies generally reported lower synergy rates than time-kill studies. The use of combination therapy led to less resistance development in vitro. The combination of a carbapenem with a polymyxin against GNB, especially A. baumannii, is supported in vitro by high synergy rates, with low antagonism and less resistance development. These findings should be examined in clinical studies.

Systematic Review and Meta-Analysis of In Vitro Synergy of Polymyxins and Carbapenems

Science.gov (United States)

Avni, Tomer; Leibovici, Leonard; Adler, Amos; Friberg, Lena; Stergiopoulou, Theodouli; Carmeli, Yehuda; Paul, Mical

2013-01-01

Our objective was to examine the evidence of in vitro synergy of polymyxin-carbapenem combination therapy against Gram-negative bacteria (GNB). A systematic review and meta-analysis were performed. All studies examining in vitro interactions of antibiotic combinations consisting of any carbapenem with colistin or polymyxin B against any GNB were used. A broad search was conducted with no language, date, or publication status restrictions. Synergy rates, defined as a fractional inhibitory concentration index of ≤0.5 or a >2-log reduction in CFU, were pooled separately for time-kill, checkerboard, and Etest methods in a mixed-effect meta-analysis of rates. We examined whether the synergy rate depended on the testing method, type of antibiotic, bacteria, and resistance to carbapenems. Pooled rates with 95% confidence intervals (CI) are shown. Thirty-nine published studies and 15 conference proceeding were included, reporting on 246 different tests on 1,054 bacterial isolates. In time-kill studies, combination therapy showed synergy rates of 77% (95% CI, 64 to 87%) for Acinetobacter baumannii, 44% (95% CI, 30 to 59%) for Klebsiella pneumoniae, and 50% (95% CI, 30 to 69%) for Pseudomonas aeruginosa, with low antagonism rates for all. Doripenem showed high synergy rates for all three bacteria. For A. baumannii, meropenem was more synergistic than imipenem, whereas for P. aeruginosa the opposite was true. Checkerboard and Etest studies generally reported lower synergy rates than time-kill studies. The use of combination therapy led to less resistance development in vitro. The combination of a carbapenem with a polymyxin against GNB, especially A. baumannii, is supported in vitro by high synergy rates, with low antagonism and less resistance development. These findings should be examined in clinical studies. PMID:23917322

A meta-analysis of the effectiveness of individually oriented Cognitive Behavior Therapy (CBT) for severe agressive behavior in adolescents

NARCIS (Netherlands)

Hoogsteder, L.M; Stams, G.J.J.M.; Figge, M.A.; Changoe, K.; van Horn, J.; Hendriks, J.; Wissink, I.B.

2015-01-01

This meta-analysis, including six studies (13 effect sizes) and 164 adolescents, examined the effectiveness of individually oriented treatment (which means that the intervention contained at least an individual component, possibly in combination with group and/or family therapy) with CBT-elements

A meta-analysis of the effectiveness of individually oriented Cognitive Behavioral Treatment (CBT) for severe agressive behavior in adolescents

NARCIS (Netherlands)

Hoogsteder, L.M.; Stams, G.J.J.M.; Figge, M.A.; Changoe, K.; van Horn, J.E.; Hendriks, J.; Wissink, I.B.

2015-01-01

This meta-analysis, including six studies (13 effect sizes) and 164 adolescents, examined the effectiveness of individually oriented treatment (which means that the intervention contained at least an individual component, possibly in combination with group and/or family therapy) with CBT-elements

Improved resolution in the position of drought-related QTLs in a single mapping population of rice by meta-analysis

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Courtois Brigitte

2009-06-01

Full Text Available Abstract Background Meta-analysis of QTLs combines the results of several QTL detection studies and provides narrow confidence intervals for meta-QTLs, permitting easier positional candidate gene identification. It is usually applied to multiple mapping populations, but can be applied to one. Here, a meta-analysis of drought related QTLs in the Bala × Azucena mapping population compiles data from 13 experiments and 25 independent screens providing 1,650 individual QTLs separated into 5 trait categories; drought avoidance, plant height, plant biomass, leaf morphology and root traits. A heat map of the overlapping 1 LOD confidence intervals provides an overview of the distribution of QTLs. The programme BioMercator is then used to conduct a formal meta-analysis at example QTL clusters to illustrate the value of meta-analysis of QTLs in this population. Results The heat map graphically illustrates the genetic complexity of drought related traits in rice. QTLs can be linked to their physical position on the rice genome using Additional file 1 provided. Formal meta-analysis on chromosome 1, where clusters of QTLs for all trait categories appear close, established that the sd1 semi-dwarfing gene coincided with a plant height meta-QTL, that the drought avoidance meta-QTL was not likely to be associated with this gene, and that this meta-QTL was not pleiotropic with close meta-QTLs for leaf morphology and root traits. On chromosome 5, evidence suggests that a drought avoidance meta-QTL was pleiotropic with leaf morphology and plant biomass meta-QTLs, but not with meta-QTLs for root traits and plant height 10 cM lower down. A region of dense root QTL activity graphically visible on chromosome 9 was dissected into three meta-QTLs within a space of 35 cM. The confidence intervals for meta-QTLs obtained ranged from 5.1 to 14.5 cM with an average of 9.4 cM, which is approximately 180 genes in rice. Additional file 1 Alignment of markers on the Bala �

Contemporary management of frontal sinus mucoceles: a meta-analysis.

Science.gov (United States)

Courson, Andy M; Stankiewicz, James A; Lal, Devyani

2014-02-01

To analyze trends in the surgical management of frontal and fronto-ethmoid mucoceles through meta-analysis. Meta-analysis and case series. A systematic literature review on surgical management of frontal and fronto-ethmoid mucoceles was conducted. Studies were divided into historical (1975-2001) and contemporary (2002-2012) groups. A meta-analysis of these studies was performed. The historical and contemporary cohorts were compared (surgical approach, recurrence, and complications). To study evolution in surgical management, a senior surgeon's experience over 28 years was analyzed separately. Thirty-one studies were included for meta-analysis. The historical cohort included 425 mucoceles from 11 studies. The contemporary cohort included 542 mucoceles from 20 studies. More endoscopic techniques were used in the contemporary versus historical cohort (53.9% vs. 24.7%; P = contemporary). In the historical cohort, higher recurrence was noted in the external group (P = 0.03). Results from endoscopic and open approaches are comparable. Although endoscopic techniques are being increasingly adopted, comparison with our series shows that more cases could potentially be treated endoscopically. Frequent use of open approaches may reflect efficacy, or perhaps lack of expertise and equipment required for endoscopic management. Most contemporary authors favor endoscopic management, limiting open approaches for specific indications (unfavorable anatomy, lateral disease, and scarring). N/A. Copyright © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

[Effect of acupuncture therapy on patients with low back pain: a Meta-analysis].

Science.gov (United States)

Liang, Fei-fan; Chen, Wei-ye; Chen, Bo; Xu, Qin-guang; Zhan, Hong-sheng

2016-05-01

To systematically review the clinical efficacy of acupuncture on the patients with low back pain (LBP). Randomized controlled trials (RCTs) about pure acupuncture therapy versus other treatments in treating LBP were electronically searched in PubMed, CBM, EMbase, The Cochrane Library, CNKI, VIP and Wanfang Data from January 2004 to May 2014. The observed index on the results were the changed scores of VAS, ODI, JOA and RMDQ. Two reviewers independently screened the literatures according to the inclusion and exclusion criteria, as well as the extracted data, and assessed the methodological quality. The results of Meta-analysis was conducted by RevMan 5.2 software. Ten RCTs involved 751 patients were finally included. The results of Meta-analysis indicated that the role of pure acupuncture group in improving the VAS score was better than that of the control group, and the combined effect size was RR = -.32, 95% CI (-1.41, -1.22); Z=27.28, Pacupuncture group in improving the ODI score was better than that of the control group, and the combined effect size was RR = -5.07, 95% CI (-7.50, -2.65); Z=4.10, Pacupuncture group on improved JOA score was better than that of the control group and the combined effect size was RR=2.83, 95% CI (2.02, 3.63), Z=6.90, Pacupuncture group in improving the RMDQ score was better than that of the control group, and the combined effect size was RR = -2.80, 95% CI (-3.49, -2.11), Z=7.95, Pacupuncture may have a favorable effect on self-reported pain and functional limitations in LBP patients.

MetaFIND: A feature analysis tool for metabolomics data

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Cunningham Pádraig

2008-11-01

Full Text Available Abstract Background Metabolomics, or metabonomics, refers to the quantitative analysis of all metabolites present within a biological sample and is generally carried out using NMR spectroscopy or Mass Spectrometry. Such analysis produces a set of peaks, or features, indicative of the metabolic composition of the sample and may be used as a basis for sample classification. Feature selection may be employed to improve classification accuracy or aid model explanation by establishing a subset of class discriminating features. Factors such as experimental noise, choice of technique and threshold selection may adversely affect the set of selected features retrieved. Furthermore, the high dimensionality and multi-collinearity inherent within metabolomics data may exacerbate discrepancies between the set of features retrieved and those required to provide a complete explanation of metabolite signatures. Given these issues, the latter in particular, we present the MetaFIND application for 'post-feature selection' correlation analysis of metabolomics data. Results In our evaluation we show how MetaFIND may be used to elucidate metabolite signatures from the set of features selected by diverse techniques over two metabolomics datasets. Importantly, we also show how MetaFIND may augment standard feature selection and aid the discovery of additional significant features, including those which represent novel class discriminating metabolites. MetaFIND also supports the discovery of higher level metabolite correlations. Conclusion Standard feature selection techniques may fail to capture the full set of relevant features in the case of high dimensional, multi-collinear metabolomics data. We show that the MetaFIND 'post-feature selection' analysis tool may aid metabolite signature elucidation, feature discovery and inference of metabolic correlations.

The relationship between persuasive technology principles, adherence and effect of web-Based interventions for mental health: A meta-analysis.

Science.gov (United States)

Wildeboer, Gina; Kelders, Saskia M; van Gemert-Pijnen, Julia E W C

2016-12-01

Research has shown that web-based interventions concerning mental health can be effective, although there is a broad range in effect sizes. Why some interventions are more effective than others is not clear. Persuasive technology is one of the aspects which has a positive influence on changing attitude and/or behavior, and can contribute to better outcomes. According to the Persuasive Systems Design Model there are various principles that can be deployed. It is unknown whether the number and combinations of principles used in a web-based intervention affect the effectiveness. Another issue in web-based interventions is adherence. Little is known about the relationship of adherence on the effectiveness of web-based interventions. This study examines whether there is a relationship between the number and combinations of persuasive technology principles used in web-based interventions and the effectiveness. Also the influence of adherence on effectiveness of web-based interventions is investigated. This study elaborates on the systematic review by [37] and therefore the articles were derived from that study. Only web-based interventions were included that were intended to be used on more than one occasion and studies were excluded when no information on adherence was provided. 48 interventions targeted at mental health were selected for the current study. A within-group (WG) and between-group (BG) meta-analysis were performed and subsequently subgroup analyses regarding the relationship between the number and combinations of persuasive technology principles and effectiveness. The influence of adherence on the effectiveness was examined through a meta-regression analysis. For the WG meta-analysis 40 treatment groups were included. The BG meta-analysis included 19 studies. The mean pooled effect size in the WG meta-analysis was large and significant (Hedges' g=0.94), while for the BG meta-analysis this was moderate to large and significant (Hedges' g=0.78) in favor of

Meta-analysis for quantitative microbiological risk assessments and benchmarking data

NARCIS (Netherlands)

Besten, den H.M.W.; Zwietering, M.H.

2012-01-01

Meta-analysis studies are increasingly being conducted in the food microbiology area to quantitatively integrate the findings of many individual studies on specific questions or kinetic parameters of interest. Meta-analyses provide global estimates of parameters and quantify their variabilities, and

A systematic review and meta-analysis of the effectiveness of nudging to increase fruit and vegetable choice.

Science.gov (United States)

Broers, Valérie J V; De Breucker, Céline; Van den Broucke, Stephan; Luminet, Olivier

2017-10-01

Nudging refers to interventions that organize the choice architecture in order to alter people's behaviour in a predictable way without forbidding any options or significantly changing their economic incentives. As a strategy to encourage healthy behaviour, nudging can serve as a complement to health education. However, the empirical evidence regarding the effectiveness of nudging as a way to influence food choice remains contradictory. To address this issue, a systematic review and meta-analysis was conducted to test the effects of nudging to encourage people to select more fruit and vegetables. A systematic literature search was performed on PubMed, Medline, PsycInfo, Cochrane library, Scopus and Google Scholar. After quality assessment, 20 articles (23 studies) were retained for narrative synthesis. Twelve articles (14 studies) contained enough information to calculate effect-sizes for meta-analysis using Comprehensive Meta-analysis software. The meta-analysis shows that nudging interventions that aim to increase fruit and/or vegetable choice/sales/servings have a moderately significant effect (d = 0.30), with the largest effect for altering placement (d = 0.39) and combined nudges (d = 0.28). The results of this review provide an indication of the effectiveness of nudging on fruit and vegetable choice in terms of actual effect-sizes, while also highlighting the problems that must be addressed before more definitive conclusions can be drawn. © The Author 2017. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

Long-term Hearing Preservation After Resection of Vestibular Schwannoma: A Systematic Review and Meta-analysis.

Science.gov (United States)

Ahsan, Syed F; Huq, Farhan; Seidman, Michael; Taylor, Andrew

2017-12-01

The objective is to perform a systematic review and meta-analysis of the literature on the long-term results of hearing preservation after vestibular schwannoma resection. Ovid/Medline, PubMed, Embase, and the Cochrane library from January 1980 to January 2015. Inclusion criteria: age ≥18 years, minimum 10 patients in the treatment group, hearing preserving microsurgery, no previous radiation treatment, serviceable hearing at immediate postop follow-up, hearing outcomes reported using Gardner Robinson or the American Academy of Otolaryngology-Head and Neck Surgeons hearing grading scales, and average follow-up of 5 years. Preoperative, immediate postoperative, and last follow-up audiograms were required. Exclusion criteria included neurofibromatosis type 2 patients and surgery for salvage therapy or decompression. Quality evaluated using Methodological Index for Non-Randomized Studies. Meta-analysis was performed using R v3.2.2, Metafor package v 1.9-7. Cohen's D was used to determine effect size. Ten reports had at least 5-year follow-up and used standardized hearing grading scales. The systematic review found that if hearing was preserved at Class A or B at early postop visit, the chance of preserving hearing at 5 years was excellent. Those who maintained speech discrimination score ≥ 89% at the early postoperative follow-up had better long-term hearing preservation. The meta-analysis reveals that only preoperative and postoperative pure-tone average was associated with long-term hearing preservation. Long-term (>5 yr) hearing durability rates are generally very good. Most studies do not report patient and tumor characteristics, therefore precluding combining studies for meta-analysis. Only preoperative and postoperative postoperative pure-tone average was associated with long-term hearing durability.

A meta-analysis of echocardiographic measurements of the left heart for the development of normative reference ranges in a large international cohort

DEFF Research Database (Denmark)

Møgelvang, Rasmus

2014-01-01

, from multiple studies around the world. METHODS AND RESULTS: The Echocardiographic Normal Ranges Meta-Analysis of the Left heart (EchoNoRMAL) collaboration was established and population-based data sets of echocardiographic measurements combined to perform an individual person data meta-analysis. Data...... from 43 studies were received, representing 51 222 subjects, of which 22 404 adults aged 18-80 years were without clinical cardiovascular or renal disease, hypertension or diabetes. Quantile regression or an appropriate parametric regression method will be used to derive reference values at the 5th...

Network meta-analysis using R: a review of currently available automated packages.

Directory of Open Access Journals (Sweden)

Binod Neupane

Full Text Available Network meta-analysis (NMA--a statistical technique that allows comparison of multiple treatments in the same meta-analysis simultaneously--has become increasingly popular in the medical literature in recent years. The statistical methodology underpinning this technique and software tools for implementing the methods are evolving. Both commercial and freely available statistical software packages have been developed to facilitate the statistical computations using NMA with varying degrees of functionality and ease of use. This paper aims to introduce the reader to three R packages, namely, gemtc, pcnetmeta, and netmeta, which are freely available software tools implemented in R. Each automates the process of performing NMA so that users can perform the analysis with minimal computational effort. We present, compare and contrast the availability and functionality of different important features of NMA in these three packages so that clinical investigators and researchers can determine which R packages to implement depending on their analysis needs. Four summary tables detailing (i data input and network plotting, (ii modeling options, (iii assumption checking and diagnostic testing, and (iv inference and reporting tools, are provided, along with an analysis of a previously published dataset to illustrate the outputs available from each package. We demonstrate that each of the three packages provides a useful set of tools, and combined provide users with nearly all functionality that might be desired when conducting a NMA.

Systematic review and meta-analysis of closed suction drainage versus non-drainage in primary hip arthroplasty.

LENUS (Irish Health Repository)

Kelly, Enda G

2014-03-01

The routine use of drains in surgery has been dogmatically instituted in some disciplines. Orthopaedic surgery is one such sub-speciality. The use of postoperative closed suction drainage in total hip arthroplasty (THA) has become increasingly controversial with multiple randomised control trials performed to assess the benefit to outcome in THA. The hypothesis of this systematic review is that closed suction drainage does not infer a benefit and increase transfusion requirements of primary total hip arthroplasty patients. A systematic review and meta-analysis was conducted adhering to the PRISMA guidelines. A search of the available literature was performed on PubMed, Cochrane Central Registry of Controlled Trials, MEDLINE (OVID) and EMBASE using a combination of MeSH terms and Boolean operators. All data analysis was performed using the Cochrane Collaboration\\'s Review Manager 5.1. Sixteen studies (n=2705) were included in the analysis. Post-operative closed suction drainage was found to increase total blood loss and blood transfusion requirements (p<0.05). Surgical site infection demonstrated no significant difference between the two groups (p=0.82). No significant difference in haematoma formation between groups (p=0.19) was elicited. The routine use of closed suction drainage systems post primary hip arthroplasty is not supported by this meta-analysis. However, the heterogeneity between studies does limit the accuracy of the meta-analysis.

Efficacy and safety of statins and exercise combination therapy compared to statin monotherapy in patients with dyslipidaemia: A systematic review and meta-analysis.

Science.gov (United States)

Gui, Ya-Jun; Liao, Cai-Xiu; Liu, Qiong; Guo, Yuan; Yang, Tao; Chen, Jing-Yuan; Wang, Ya-Ting; Hu, Jia-Hui; Xu, Dan-Yan

2017-06-01

Background Statin treatment in association with physical exercise can substantially reduce mortality in dyslipidaemic individuals. However, the available data to compare the efficacy and safety of statins and exercise combination therapy with statin monotherapy are limited. Design Systematic review and meta-analysis. Methods We systematically searched PubMed, Embase and the Cochrane Library from database inception until December 2016. We included randomised and non-randomised studies that compared the efficacy and safety of statins and exercise combination therapy with statin monotherapy in patients with dyslipidaemia. Standardised mean differences were calculated and pooled by means of fixed effects models. The risk of bias and heterogeneity among trials was also assessed. Seven articles were assessed in terms of the efficacy of therapy and 13 from the viewpoint of therapeutic safety. Results In terms of efficacy, statins and exercise combination decreased the incidence of diabetes mellitus, improved insulin sensitivity and inflammation, but caused no change in lipid profile compared to statins alone. In terms of safety, statins and exercise combination increased peak oxygen uptake (standardised mean difference 1.01, 95% confidence interval 0.46 to 1.57) compared to statins alone. In contrast to statin-induced myopathy, chronic exercise training prior to statin treatment could counteract statin-induced adverse effects in skeletal muscle. Conclusion Statins and exercise combination therapy is more effective than statin monotherapy in terms of insulin sensitivity, inflammation and exercise capacity. The small number of studies warrants the need for more randomised controlled trials evaluating the efficacy and safety of combination therapy.

A Systematic Review and Meta-Analysis of Baseline Ohip-Edent Scores.

Science.gov (United States)

Duale, J M J; Patel, Y A; Wu, J; Hyde, T P

2018-03-01

OHIP-EDENT is widely used in the literature to assess Oral-Health-Related-Quality-of-Life (OHRQoL) for edentulous patients. However the normal variance and mean of the baseline OHIP scores has not been reported. It would facilitate critical appraisal of studies if we had knowledge of the normal variation and mean of baseline OHIP-EDENT scores. An established figure for baseline OHIP-EDENT, obtained from a meta-analysis, would simplify comparisons of studies and quantify variations in initial OHRQoL of the trial participants. The aim of this study is to quantify a normal baseline value for pre-operative OHIP-EDENT scores by a systematic review and meta-analysis of the available literature. A systematic literature review was carried. 83 papers were identified that included OHIP-EDENT values. After screening and eligibility assessment, 7 papers were selected and included in the meta-analysis. A meta-analysis for the 7 papers by a random-effect model yielded a mean baseline OHIP-EDENT score of 28.63 with a 95% Confidence intervals from 21.93 to 35.34. A pre-operative baseline OHIP-EDENT has been established by meta-analysis of published papers. This will facilitate the comparison of the initial OHRQoL of one study population to that found elsewhere in the published literature. Copyright© 2018 Dennis Barber Ltd.

Effect of Sling Exercise Training on Balance in Patients with Stroke: A Meta-Analysis.

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Chen, Lianghua; Chen, Junqi; Peng, Qiyuan; Chen, Jingjie; Zou, Yucong; Liu, Gang

2016-01-01

This study aims to evaluate the effect of sling exercise training (SET) on balance in patients with stroke. PubMed, Cochrane Library, Ovid LWW, CBM, CNKI, WanFang, and VIP databases were searched for randomized controlled trials of the effect of SET on balance in patients with stroke. The study design and participants were subjected to metrological analysis. Berg balance Scale (BBS), Barthel index score (BI), and Fugl-Meyer Assessment (FMA) were used as independent parameters for evaluating balance function, activities of daily living(ADL) and motor function after stroke respectively, and were subjected to meta-analysis by RevMan5.3 software. Nine studies with 460 participants were analyzed. Results of meta-analysis showed that the SET treatment combined with conventional rehabilitation was superior to conventional rehabilitation treatments, with increased degrees of BBS (WMD = 3.81, 95% CI [0.15, 7.48], P = 0.04), BI (WMD = 12.98, 95% CI [8.39, 17.56], P risk of bias. Therefore, more multi-center and large-sampled randomized controlled trials are needed to confirm its clinical applications.

Meta-analysis of the relationship between TQM and Business Performance

International Nuclear Information System (INIS)

Ahmad M F; Zakuan N; Jusoh A; Tasir Z; Takala J

2013-01-01

Meta-analysis has been conducted based on 20 previous works from 4,040 firms at 16 countries from Asia, Europe and America. Throughout this paper a meta-analysis, this paper reviews the relationships between TQM and business performance amongst the regions. Meta-analysis result concludes that the average of rc is 0.47; Asia (rc=0.54), America (rc=0.43) and Europe (rc=0.38). The analysis also shows that Asia developed countries have greatest impact of TQM (rc=0.56). However, the analysis of ANOVA and t-test show that there is no significant difference amongst type of country (developed and developing countries) and regions at p=0.05. In addition, the average result of rc 2 is 0.24; Asia (rc 2 =0.33), America (rc 2 =0.22) and Europe (rc 2 =0.15). Meanwhile, rc 2 in developing countries (rc 2 =0.28) are higher than developed countries (rc 2 =0.21).

Efficacy of intensive versus nonintensive physiotherapy in children with cerebral palsy: a meta-analysis.

Science.gov (United States)

Arpino, Carla; Vescio, Maria Fenicia; De Luca, Angela; Curatolo, Paolo

2010-06-01

A commonly used treatment for cerebral palsy in children is so-called 'conventional therapy', which includes physiotherapy or the neurodevelopmental approach. Although more intensive rehabilitative treatment is thought to be more effective than less intensive interventions, this assumption has not been proven. In this study we compared the efficacy of intensive versus nonintensive rehabilitative treatment in children with cerebral palsy. A meta-analysis of the studies published between January 1996 and July 2007 was performed. infants/children/adolescents (1-18 years old); randomized controlled trials using, as outcome measure, the Gross Motor Function Measure score. studies that included therapies not generally used in 'so-called' conventional treatment (i.e. constraint, taping). Treatment effects were combined using the weighted mean difference method. Fixed and random effect meta-analyses were carried out and results were compared. Heterogeneity was also assessed. Funnel plots were examined and the presence of small-study effects was tested. Intensive therapy tended to have a greater effect than nonintensive therapy (1.32; 95% confidence interval: 0.55-2.10). The effect of intensive treatment tended to be apparently stronger for children 2 years of age. Our meta-analysis shows that, in children with cerebral palsy, intensive conventional therapy may improve the functional motor outcome, but the effect size seems to be modest.

The Efficacy and Safety of the Combination of Total Glucosides of Peony and Leflunomide for the Treatment of Rheumatoid Arthritis: A Systemic Review and Meta-Analysis.

Science.gov (United States)

Feng, Zhitao; Xu, Juan; He, Guochao; Cao, Meiqun; Duan, Lihong; Chen, Liguo; Wu, Zhengzhi

2016-01-01

Objective. To evaluate the efficacy and safety of the total glucosides of peony (TGP) and leflunomide (LEF) for the treatment of rheumatoid arthritis (RA). Methods. Randomized controlled trials (RCTs) on the efficacy and safety of the combination of TGP and LEF versus LEF alone for the treatment of RA were retrieved by searching PubMed, EMBASE, Cochrane Library, the China National Knowledge Infrastructure database, and Wanfang database. Results. Eight RCTs including 643 RA patients were included in the present meta-analysis. The quality of included studies was poor. The levels of ESR (P TGP and LEF were significantly lower than RA patients who received LEF therapy alone. The pooled results suggest that the combination of TGP and LEF caused less abnormal liver function than LEF alone (P = 0.02). No significant difference in the gastrointestinal discomfort was identified between the combination of TGP and LEF and LEF alone groups (P = 0.18). Conclusion. The combination of TGP and LEF in treatment of RA presented the characteristics of notably decreasing the levels of laboratory indexes and higher safety in terms of liver function. However, this conclusion should be further investigated based on a larger sample size.

Autogenic training: a meta-analysis of clinical outcome studies.

Science.gov (United States)

Stetter, Friedhelm; Kupper, Sirko

2002-03-01

Autogenic training (AT) is a self-relaxation procedure by which a psychophysiological determined relaxation response is elicited. A meta-analysis was performed to evaluate the clinical effectiveness of AT. Seventy-three controlled outcome studies were found (published 1952-99). Sixty studies (35 randomized controlled trials [RCT]) qualified for inclusion in the meta-analysis. Medium-to-large effect sizes (ES) occurred for pre-post comparisons of disease-specific AT-effects, with the RCTs showing larger ES. When AT was compared to real control conditions, medium ES were found. Comparisons of AT versus other psychological treatment mostly resulted in no effects or small negative ES. This pattern of results was stable at follow-up. Unspecific AT-effects (i.e., effects on mood, cognitive performance, quality of life, and physiological variables) tended to be even larger than main effects. Separate meta-analyses for different disorders revealed a significant reduction of the heterogeneity of ES. Positive effects (medium range) of AT and of AT versus control in the meta-analysis of at least 3 studies were found for tension headache/migraine, mild-to-moderate essential hypertension, coronary heart disease, asthma bronchiale, somatoform pain disorder (unspecified type), Raynaud's disease, anxiety disorders, mild-to-moderate depression/dysthymia, and functional sleep disorders.

The prevalence of food allergy: a meta-analysis.

Science.gov (United States)

Rona, Roberto J; Keil, Thomas; Summers, Colin; Gislason, David; Zuidmeer, Laurian; Sodergren, Eva; Sigurdardottir, Sigurveig T; Lindner, Titia; Goldhahn, Klaus; Dahlstrom, Jorgen; McBride, Doreen; Madsen, Charlotte

2007-09-01

There is uncertainty about the prevalence of food allergy in communities. To assess the prevalence of food allergy by performing a meta-analysis according to the method of assessment used. The foods assessed were cow's milk, hen's egg, peanut, fish, shellfish, and an overall estimate of food allergy. We summarized the information in 5 categories: self-reported symptoms, specific IgE positive, specific skin prick test positive, symptoms combined with sensitization, and food challenge studies. We systematically searched MEDLINE and EMBASE for publications since 1990. The meta-analysis included only original studies. They were stratified by age groups: infant/preschool, school children, and adults. A total of 934 articles were identified, but only 51 were considered appropriate for inclusion. The prevalence of self-reported food allergy was very high compared with objective measures. There was marked heterogeneity between studies regardless of type of assessment or food item considered, and in most analyses this persisted after age stratification. Self-reported prevalence of food allergy varied from 1.2% to 17% for milk, 0.2% to 7% for egg, 0% to 2% for peanuts and fish, 0% to 10% for shellfish, and 3% to 35% for any food. There is a marked heterogeneity in the prevalence of food allergy that could be a result of differences in study design or methodology, or differences between populations. We recommend that measurements be made by using standardized methods, if possible food challenge. We need to be cautious in estimates of prevalence based only on self-reported food allergy.

Fruits, vegetables and breast cancer risk: a systematic review and meta-analysis of prospective studies.

Science.gov (United States)

Aune, D; Chan, D S M; Vieira, A R; Rosenblatt, D A Navarro; Vieira, R; Greenwood, D C; Norat, T

2012-07-01

Evidence for an association between fruit and vegetable intake and breast cancer risk is inconclusive. To clarify the association, we conducted a systematic review and meta-analysis of the evidence from prospective studies. We searched PubMed for prospective studies of fruit and vegetable intake and breast cancer risk until April 30, 2011. We included fifteen prospective studies that reported relative risk estimates and 95 % confidence intervals (CIs) of breast cancer associated with fruit and vegetable intake. Random effects models were used to estimate summary relative risks. The summary relative risk (RR) for the highest versus the lowest intake was 0.89 (95 % CI: 0.80-0.99, I (2) = 0 %) for fruits and vegetables combined, 0.92 (95 % CI: 0.86-0.98, I (2) = 9 %) for fruits, and 0.99 (95 % CI: 0.92-1.06, I (2) = 20 %) for vegetables. In dose-response analyses, the summary RR per 200 g/day was 0.96 (95 % CI: 0.93-1.00, I (2) = 2 %) for fruits and vegetables combined, 0.94 (95 % CI: 0.89-1.00, I (2) = 39 %) for fruits, and 1.00 (95 % CI: 0.95-1.06, I (2) = 17 %) for vegetables. In this meta-analysis of prospective studies, high intake of fruits, and fruits and vegetables combined, but not vegetables, is associated with a weak reduction in risk of breast cancer.

A joint frailty-copula model between tumour progression and death for meta-analysis.

Science.gov (United States)

Emura, Takeshi; Nakatochi, Masahiro; Murotani, Kenta; Rondeau, Virginie

2017-12-01

Dependent censoring often arises in biomedical studies when time to tumour progression (e.g., relapse of cancer) is censored by an informative terminal event (e.g., death). For meta-analysis combining existing studies, a joint survival model between tumour progression and death has been considered under semicompeting risks, which induces dependence through the study-specific frailty. Our paper here utilizes copulas to generalize the joint frailty model by introducing additional source of dependence arising from intra-subject association between tumour progression and death. The practical value of the new model is particularly evident for meta-analyses in which only a few covariates are consistently measured across studies and hence there exist residual dependence. The covariate effects are formulated through the Cox proportional hazards model, and the baseline hazards are nonparametrically modeled on a basis of splines. The estimator is then obtained by maximizing a penalized log-likelihood function. We also show that the present methodologies are easily modified for the competing risks or recurrent event data, and are generalized to accommodate left-truncation. Simulations are performed to examine the performance of the proposed estimator. The method is applied to a meta-analysis for assessing a recently suggested biomarker CXCL12 for survival in ovarian cancer patients. We implement our proposed methods in R joint.Cox package.

Small studies are more heterogeneous than large ones: a meta-meta-analysis

NARCIS (Netherlands)

Hout, J. in't; Ioannidis, J.P.; Borm, G.F.; Goeman, J.J.

2015-01-01

OBJECTIVES: Between-study heterogeneity plays an important role in random-effects models for meta-analysis. Most clinical trials are small, and small trials are often associated with larger effect sizes. We empirically evaluated whether there is also a relationship between trial size and

Meta-analysis of grain yield QTL identified during agricultural drought in grasses showed consensus.

Science.gov (United States)

Swamy, B P Mallikarjuna; Vikram, Prashant; Dixit, Shalabh; Ahmed, H U; Kumar, Arvind

2011-06-16

In the last few years, efforts have been made to identify large effect QTL for grain yield under drought in rice. However, identification of most precise and consistent QTL across the environments and genetics backgrounds is essential for their successful use in Marker-assisted Selection. In this study, an attempt was made to locate consistent QTL regions associated with yield increase under drought by applying a genome-wide QTL meta-analysis approach. The integration of 15 maps resulted in a consensus map with 531 markers and a total map length of 1821 cM. Fifty-three yield QTL reported in 15 studies were projected on a consensus map and meta-analysis was performed. Fourteen meta-QTL were obtained on seven chromosomes. MQTL1.2, MQTL1.3, MQTL1.4, and MQTL12.1 were around 700 kb and corresponded to a reasonably small genetic distance of 1.8 to 5 cM and they are suitable for use in marker-assisted selection (MAS). The meta-QTL for grain yield under drought coincided with at least one of the meta-QTL identified for root and leaf morphology traits under drought in earlier reports. Validation of major-effect QTL on a panel of random drought-tolerant lines revealed the presence of at least one major QTL in each line. DTY12.1 was present in 85% of the lines, followed by DTY4.1 in 79% and DTY1.1 in 64% of the lines. Comparative genomics of meta-QTL with other cereals revealed that the homologous regions of MQTL1.4 and MQTL3.2 had QTL for grain yield under drought in maize, wheat, and barley respectively. The genes in the meta-QTL regions were analyzed by a comparative genomics approach and candidate genes were deduced for grain yield under drought. Three groups of genes such as stress-inducible genes, growth and development-related genes, and sugar transport-related genes were found in clusters in most of the meta-QTL. Meta-QTL with small genetic and physical intervals could be useful in Marker-assisted selection individually and in combinations. Validation and comparative

Genome-Wide Meta-Analysis of Longitudinal Alcohol Consumption Across Youth and Early Adulthood.

Science.gov (United States)

Adkins, Daniel E; Clark, Shaunna L; Copeland, William E; Kennedy, Martin; Conway, Kevin; Angold, Adrian; Maes, Hermine; Liu, Youfang; Kumar, Gaurav; Erkanli, Alaattin; Patkar, Ashwin A; Silberg, Judy; Brown, Tyson H; Fergusson, David M; Horwood, L John; Eaves, Lindon; van den Oord, Edwin J C G; Sullivan, Patrick F; Costello, E J

2015-08-01

The public health burden of alcohol is unevenly distributed across the life course, with levels of use, abuse, and dependence increasing across adolescence and peaking in early adulthood. Here, we leverage this temporal patterning to search for common genetic variants predicting developmental trajectories of alcohol consumption. Comparable psychiatric evaluations measuring alcohol consumption were collected in three longitudinal community samples (N=2,126, obs=12,166). Consumption-repeated measurements spanning adolescence and early adulthood were analyzed using linear mixed models, estimating individual consumption trajectories, which were then tested for association with Illumina 660W-Quad genotype data (866,099 SNPs after imputation and QC). Association results were combined across samples using standard meta-analysis methods. Four meta-analysis associations satisfied our pre-determined genome-wide significance criterion (FDR<0.1) and six others met our 'suggestive' criterion (FDR<0.2). Genome-wide significant associations were highly biological plausible, including associations within GABA transporter 1, SLC6A1 (solute carrier family 6, member 1), and exonic hits in LOC100129340 (mitofusin-1-like). Pathway analyses elaborated single marker results, indicating significant enriched associations to intuitive biological mechanisms, including neurotransmission, xenobiotic pharmacodynamics, and nuclear hormone receptors (NHR). These findings underscore the value of combining longitudinal behavioral data and genome-wide genotype information in order to study developmental patterns and improve statistical power in genomic studies.

Tooth erosion and eating disorders: a systematic review and meta-analysis.

Directory of Open Access Journals (Sweden)

Ana Paula Hermont

Full Text Available BACKGROUND: Eating disorders are associated with the highest rates of morbidity and mortality of any mental disorders among adolescents. The failure to recognize their early signs can compromise a patient's recovery and long-term prognosis. Tooth erosion has been reported as an oral manifestation that might help in the early detection of eating disorders. OBJECTIVES: The aim of this systematic review and meta-analysis was to search for scientific evidence regarding the following clinical question: Do eating disorders increase the risk of tooth erosion? METHODS: An electronic search addressing eating disorders and tooth erosion was conducted in eight databases. Two independent reviewers selected studies, abstracted information and assessed its quality. Data were abstracted for meta-analysis comparing tooth erosion in control patients (without eating disorders vs. patients with eating disorders; and patients with eating disorder risk behavior vs. patients without such risk behavior. Combined odds ratios (ORs and a 95% confidence interval (CI were obtained. RESULTS: Twenty-three papers were included in the qualitative synthesis and assessed by a modified version of the Newcastle-Ottawa Scale. Fourteen papers were included in the meta-analysis. Patients with eating disorders had more risk of tooth erosion (OR = 12.4, 95%CI = 4.1-37.5. Patients with eating disorders who self-induced vomiting had more risk of tooth erosion than those patients who did not self-induce vomiting (OR = 19.6, 95%CI = 5.6-68.8. Patients with risk behavior of eating disorder had more risk of tooth erosion than patients without such risk behavior (Summary OR = 11.6, 95%CI = 3.2-41.7. CONCLUSION: The scientific evidence suggests a causal relationship between tooth erosion and eating disorders and purging practices. Nevertheless, there is a lack of scientific evidence to fulfill the basic criteria of causation between the risk behavior for eating disorders and tooth erosion.

Systematic review and meta-analysis of the effects of football heading.

Science.gov (United States)

Kontos, Anthony P; Braithwaite, Rock; Chrisman, Sara P D; McAllister-Deitrick, Jamie; Symington, Larissa; Reeves, Valerie L; Collins, Michael W

2017-08-01

The objective of this study was to provide a meta-analysis examining the effects of football heading. Meta-analytical review on football heading effects on neurocognitive performance, cognition and symptom reports. Combinations of the key terms were entered into the following electronic database search engines: Cochrane Libraries, PyscARTICLE, PyscINFO, PubMed, ProQuest, SPORTDiscus and Web of Science on 7 July 2016. The following inclusion criteria were used to determine eligibility for studies: (1) the study examined and reported on soccer athletes; (2) the population's age, sex and sport position was described; (3) cognitive function, symptoms, balance or other outcomes were quantitatively measured; (4) football heading exposure was quantitatively measured between at least two groups and (5) the study was written in the English language after December 1979. The literature search process identified 467 unique studies. After applying exclusion criteria, 28 studies remained. Included studies had a total of 2288 participants (female participants =933, male participants =1355), aged 13-70 years. The overall results of random effects modelling of football heading were found to be inconclusive across all outcomes, groups and time points. No moderating variables related to methodological, sample or study characteristics were supported in the analysis; age was a potential moderating variable. We provide the first meta-analytical review of football heading effects aggregated from multiple studies and extended findings from a recent systematic review of the effects of football heading. Our analysis indicates no overall effect for heading a football on adverse outcomes. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Identification of cytokinin-responsive genes using microarray meta-analysis and RNA-Seq in Arabidopsis.

Science.gov (United States)

Bhargava, Apurva; Clabaugh, Ivory; To, Jenn P; Maxwell, Bridey B; Chiang, Yi-Hsuan; Schaller, G Eric; Loraine, Ann; Kieber, Joseph J

2013-05-01

Cytokinins are N(6)-substituted adenine derivatives that play diverse roles in plant growth and development. We sought to define a robust set of genes regulated by cytokinin as well as to query the response of genes not represented on microarrays. To this end, we performed a meta-analysis of microarray data from a variety of cytokinin-treated samples and used RNA-seq to examine cytokinin-regulated gene expression in Arabidopsis (Arabidopsis thaliana). Microarray meta-analysis using 13 microarray experiments combined with empirically defined filtering criteria identified a set of 226 genes differentially regulated by cytokinin, a subset of which has previously been validated by other methods. RNA-seq validated about 73% of the up-regulated genes identified by this meta-analysis. In silico promoter analysis indicated an overrepresentation of type-B Arabidopsis response regulator binding elements, consistent with the role of type-B Arabidopsis response regulators as primary mediators of cytokinin-responsive gene expression. RNA-seq analysis identified 73 cytokinin-regulated genes that were not represented on the ATH1 microarray. Representative genes were verified using quantitative reverse transcription-polymerase chain reaction and NanoString analysis. Analysis of the genes identified reveals a substantial effect of cytokinin on genes encoding proteins involved in secondary metabolism, particularly those acting in flavonoid and phenylpropanoid biosynthesis, as well as in the regulation of redox state of the cell, particularly a set of glutaredoxin genes. Novel splicing events were found in members of some gene families that are known to play a role in cytokinin signaling or metabolism. The genes identified in this analysis represent a robust set of cytokinin-responsive genes that are useful in the analysis of cytokinin function in plants.

GACT: a Genome build and Allele definition Conversion Tool for SNP imputation and meta-analysis in genetic association studies.

Science.gov (United States)

Sulovari, Arvis; Li, Dawei

2014-07-19

Genome-wide association studies (GWAS) have successfully identified genes associated with complex human diseases. Although much of the heritability remains unexplained, combining single nucleotide polymorphism (SNP) genotypes from multiple studies for meta-analysis will increase the statistical power to identify new disease-associated variants. Meta-analysis requires same allele definition (nomenclature) and genome build among individual studies. Similarly, imputation, commonly-used prior to meta-analysis, requires the same consistency. However, the genotypes from various GWAS are generated using different genotyping platforms, arrays or SNP-calling approaches, resulting in use of different genome builds and allele definitions. Incorrect assumptions of identical allele definition among combined GWAS lead to a large portion of discarded genotypes or incorrect association findings. There is no published tool that predicts and converts among all major allele definitions. In this study, we have developed a tool, GACT, which stands for Genome build and Allele definition Conversion Tool, that predicts and inter-converts between any of the common SNP allele definitions and between the major genome builds. In addition, we assessed several factors that may affect imputation quality, and our results indicated that inclusion of singletons in the reference had detrimental effects while ambiguous SNPs had no measurable effect. Unexpectedly, exclusion of genotypes with missing rate > 0.001 (40% of study SNPs) showed no significant decrease of imputation quality (even significantly higher when compared to the imputation with singletons in the reference), especially for rare SNPs. GACT is a new, powerful, and user-friendly tool with both command-line and interactive online versions that can accurately predict, and convert between any of the common allele definitions and between genome builds for genome-wide meta-analysis and imputation of genotypes from SNP-arrays or deep

Life history of the Harlequin ladybird, Harmonia axyridis; a global meta-analysis

NARCIS (Netherlands)

Raak-van den Berg, C.L.; Hemerik, A.; Werf, van der W.; Jong, de P.W.; Lenteren, van J.C.

2017-01-01

Data collected en used for a meta analysis on life history data of H. axyridis. And the resulting 20 best models for each life history characteristic. Published in the paper: Life history of the Harlequin ladybird, Harmonia axyridis; a global meta-analysis.

Medical Student Research: An Integrated Mixed-Methods Systematic Review and Meta-Analysis.

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Mohamed Amgad

Full Text Available Despite the rapidly declining number of physician-investigators, there is no consistent structure within medical education so far for involving medical students in research.To conduct an integrated mixed-methods systematic review and meta-analysis of published studies about medical students' participation in research, and to evaluate the evidence in order to guide policy decision-making regarding this issue.We followed the PRISMA statement guidelines during the preparation of this review and meta-analysis. We searched various databases as well as the bibliographies of the included studies between March 2012 and September 2013. We identified all relevant quantitative and qualitative studies assessing the effect of medical student participation in research, without restrictions regarding study design or publication date. Prespecified outcome-specific quality criteria were used to judge the admission of each quantitative outcome into the meta-analysis. Initial screening of titles and abstracts resulted in the retrieval of 256 articles for full-text assessment. Eventually, 79 articles were included in our study, including eight qualitative studies. An integrated approach was used to combine quantitative and qualitative studies into a single synthesis. Once all included studies were identified, a data-driven thematic analysis was performed.Medical student participation in research is associated with improved short- and long- term scientific productivity, more informed career choices and improved knowledge about-, interest in- and attitudes towards research. Financial worries, gender, having a higher degree (MSc or PhD before matriculation and perceived competitiveness of the residency of choice are among the factors that affect the engagement of medical students in research and/or their scientific productivity. Intercalated BSc degrees, mandatory graduation theses and curricular research components may help in standardizing research education during

Psoriasis and suicidality: A systematic review and meta-analysis.

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Singh, Sanminder; Taylor, Catherine; Kornmehl, Heather; Armstrong, April W

2017-09-01

Psoriasis is associated with psychiatric comorbidities; however, the relationship between psoriasis and suicidality is not well understood. To perform a systematic review and meta-analysis that elucidates the relationship between psoriasis and suicidality. Applying the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we systematically searched the PubMed, EMBASE, PsycINFO, and Cochrane databases. We searched literature published between 1946 and 2017. We identified 18 studies with a total of 1,767,583 participants, of whom 330,207 had psoriasis. On the basis of random effects modeling, the pooled odds ratio (OR) for suicidal ideation among patients with psoriasis was 2.05 (95% confidence interval [CI], 1.54-2.74). Patients with psoriasis were more likely to exhibit suicidal behaviors (combined attempted and completed suicides) with a pooled OR of 1.26 (95% CI, 1.13-1.40). Subgroup analysis showed that patients with psoriasis were more likely to attempt suicides (OR, 1.32; 95% CI, 1.14-1.54) and complete suicide (OR, 1.20; 95% CI, 1.04-1.39) than those without psoriasis. More severe psoriasis and younger age were associated with greater likelihood of suicidality. There are few studies examining suicidality in conjunction with psoriasis severity. Patients with psoriasis have a significantly higher likelihood of suicidal ideation, suicide attempts, and completed suicides. Among patients with psoriasis, those who are younger and whose psoriasis is more severe are at particular risk for suicidality. Copyright © 2017. Published by Elsevier Inc.

Meta-Analysis of Placental Transcriptome Data Identifies a Novel Molecular Pathway Related to Preeclampsia.

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van Uitert, Miranda; Moerland, Perry D; Enquobahrie, Daniel A; Laivuori, Hannele; van der Post, Joris A M; Ris-Stalpers, Carrie; Afink, Gijs B

2015-01-01

Studies using the placental transcriptome to identify key molecules relevant for preeclampsia are hampered by a relatively small sample size. In addition, they use a variety of bioinformatics and statistical methods, making comparison of findings challenging. To generate a more robust preeclampsia gene expression signature, we performed a meta-analysis on the original data of 11 placenta RNA microarray experiments, representing 139 normotensive and 116 preeclamptic pregnancies. Microarray data were pre-processed and analyzed using standardized bioinformatics and statistical procedures and the effect sizes were combined using an inverse-variance random-effects model. Interactions between genes in the resulting gene expression signature were identified by pathway analysis (Ingenuity Pathway Analysis, Gene Set Enrichment Analysis, Graphite) and protein-protein associations (STRING). This approach has resulted in a comprehensive list of differentially expressed genes that led to a 388-gene meta-signature of preeclamptic placenta. Pathway analysis highlights the involvement of the previously identified hypoxia/HIF1A pathway in the establishment of the preeclamptic gene expression profile, while analysis of protein interaction networks indicates CREBBP/EP300 as a novel element central to the preeclamptic placental transcriptome. In addition, there is an apparent high incidence of preeclampsia in women carrying a child with a mutation in CREBBP/EP300 (Rubinstein-Taybi Syndrome). The 388-gene preeclampsia meta-signature offers a vital starting point for further studies into the relevance of these genes (in particular CREBBP/EP300) and their concomitant pathways as biomarkers or functional molecules in preeclampsia. This will result in a better understanding of the molecular basis of this disease and opens up the opportunity to develop rational therapies targeting the placental dysfunction causal to preeclampsia.

Limitations in Using Multiple Imputation to Harmonize Individual Participant Data for Meta-Analysis.

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Siddique, Juned; de Chavez, Peter J; Howe, George; Cruden, Gracelyn; Brown, C Hendricks

2018-02-01

Individual participant data (IPD) meta-analysis is a meta-analysis in which the individual-level data for each study are obtained and used for synthesis. A common challenge in IPD meta-analysis is when variables of interest are measured differently in different studies. The term harmonization has been coined to describe the procedure of placing variables on the same scale in order to permit pooling of data from a large number of studies. Using data from an IPD meta-analysis of 19 adolescent depression trials, we describe a multiple imputation approach for harmonizing 10 depression measures across the 19 trials by treating those depression measures that were not used in a study as missing data. We then apply diagnostics to address the fit of our imputation model. Even after reducing the scale of our application, we were still unable to produce accurate imputations of the missing values. We describe those features of the data that made it difficult to harmonize the depression measures and provide some guidelines for using multiple imputation for harmonization in IPD meta-analysis.

Swimming attendance during childhood and development of asthma: Meta-analysis.

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Valeriani, Federica; Protano, Carmela; Vitali, Matteo; Romano Spica, Vincenzo

2017-05-01

The association between asthma and swimming pool attendance has not been demonstrated and currently there are conflicting results. In order to clarify the association between asthma diagnosis in children and swimming pool attendance, and to assess the consistency of the available epidemiological studies, we completed a literature analysis on the relationship between the exposure to disinfection by-products in indoor swimming pools during childhood and asthma diagnosis. Following the Meta-analysis of Observational Studies in Epidemiology (MOOSE) and Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) criteria, a systematic review and meta-analysis was performed by searching MEDLINE via PubMed, TOXNET, and Scopus databases (from inception to 20 April 2015) using the key word "Asthma" together with "swimming pool", "disinfection by-products", "indoor air pollution" and "children". Inclusion criteria were: English language, a complete analytic study design involving a cohort of children (0-16 years), a well-defined definition of exposure, and the presence of data on effect and variance. Studies on in vivo, in vitro or professional and accidental exposure were excluded. After a screening process, seven reports (n = 5851 subjects) were included out of a total of 2928 references. The reported OR of the association between swimming pool attendance and asthma prevalence ranged from 0.58 to 2.30. The present meta-analysis failed to identify a significant difference in asthma development between children attending swimming pools and controls (OR, 1.084; 95% CI: 0.89-1.31). Swimming in childhood does not increase the likelihood of doctor-diagnosed asthma. Based on this meta-analysis review, the association of the disease with indoor pool attendance is still unclear. © 2016 Japan Pediatric Society.

Impact of evergreening on patients and health insurance: a meta analysis and reimbursement cost analysis of citalopram/escitalopram antidepressants

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Alkhafaji Ali A

2012-11-01

Full Text Available Abstract Background "Evergreening" refers to the numerous strategies whereby owners of pharmaceutical products use patent laws and minor drug modifications to extend their monopoly privileges on the drug. We aimed to evaluate the impact of evergreening through the case study of the antidepressant citalopram and its chiral switch form escitalopram by evaluating treatment efficacy and acceptability for patients, as well as health insurance costs for society. Methods To assess efficacy and acceptability, we performed meta-analyses for efficacy and acceptability. We compared direct evidence (meta-analysis of results of head-to-head trials and indirect evidence (adjusted indirect comparison of results of placebo-controlled trials. To assess health insurance costs, we analyzed individual reimbursement data from a representative sample of the French National Health Insurance Inter-regime Information System (SNIIR-AM from 2003 to 2010, which allowed for projecting these results to the whole SNIIR-AM population (53 million people. Results In the meta-analysis of seven head-to-head trials (2,174 patients, efficacy was significantly better for escitalopram than citalopram (combined odds ratio (OR 1.60 (95% confidence interval 1.05 to 2.46. However, for the adjusted indirect comparison of 10 citalopram and 12 escitalopram placebo-controlled trials, 2,984 and 3,777 patients respectively, efficacy was similar for the two drug forms (combined indirect OR 1.03 (0.82 to 1.30. Because of the discrepancy, we could not combine direct and indirect data (test of inconsistency, P = 0.07. A similar discrepancy was found for treatment acceptability. The overall reimbursement cost burden for the citalopram, escitalopram and its generic forms was 120.6 million Euros in 2010, with 96.8 million Euros for escitalopram. Conclusions The clinical benefit of escitalopram versus citalopram remains uncertain. In our case of evergreening, escitalopram represented a substantially

MR diffusion weighted imaging detecting cerebral infarction: a meta-analysis

International Nuclear Information System (INIS)

Yang Junle; Xu Min; Wang Peng; Zhang Qiujuan; Guo Youmin; Liu Min

2008-01-01

Objective: To determine the diagnostic value of diffusion-weighted imaging(DWI) in hyperacute and acute cerebral infarction by using Meta-analysis. Methods: Based on validity criteria for diagnostic research published by the Cochrane Methods Group on Screening and Diagnostic, studies in English and Chinese from 1997 to 2007 were selected from Medline, Cochrane, Springer, Ovid, Elsevier, LWW and CNKI( China National Knowledge Infrastructure). The characteristics of the included articles were appraised and extracted. Statistical analysis was performed with the software Meta-test 0.6 and Comprehensive meta-analysis 2.0. Heterogeneity of the included articles was tested, which was used to select proper effect model to calculate pooled weighted values of sensitivity and specificity and the corresponding 95% CI. Summary receiver operating characteristic (SROC) curve was performed and the area under the curve (Az) was calculated. Publication bias was analyzed by Funnel Plot in Comprehensive Meta- analysis 2.0. A sensitivity analysis was performed. Results: Twelve articles meeting inclusion criteria were analyzed for the value of DWI in hyperacute cerebral infarction. The pooled sensitivity, specificity and diagnostic odds ratio was 92%, 87%, 180.37 respectively, Az=0.9717. Novice is a main factor for total diagnostic effect (Q=4.34, P>0.05). Non-asymmetric funnel plot suggested the publication bias. Fifteen articles meeting inclusion criteria were analyzed for the value of DWI in both hyperacute and acute cerebral infarction (≤ 24 h). The pooled sensitivity, specificity diagnostic odds ratio was 92%, 91%, 623.62 respectively, Az=0.9659. Fixed effects model used in Meta-analysis for database suggested homogeneity (Q=2.70,P>0.05). Nonasymmetric funnel plot suggested the publication bias. Conclusions As a noninvasive method, diffusion-weighted imaging is valuable in detecting hyperacute and acute cerebral infarction. More support from multi-center prospective researches is

Meta-Analysis of Associations Between Interleukin-10 Polymorphisms and Susceptibility to Vasculitis.

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Jung, Jae Hyun; Song, Gwan Gyu; Lee, Young Ho

2015-01-01

This study determined whether interleukin-10 (IL-10) polymorphisms are associated with susceptibility to vasculitis. A meta-analysis was conducted of the associations between the IL-10 -1082 G/A, -819 C/T, and -592 C/A polymorphisms and the haplotype of the IL-10-1082 G/A, -819 C/T, -592 C/A polymorphisms and vasculitis. A total of 21 comparative studies involving 4121 patients and 5504 controls were considered in the meta-analysis. Meta-analysis revealed no association between the IL-10-1082 G allele and vasculitis in all study subjects (OR = 0.927, 95% CI = 0.780-1.102, p = 0.389). However, disease-specific meta-analysis showed an association between Wegener's granulomatosis (WG) and the IL-10-1082 G allele (OR = 0.729, 95% CI = 0.547-0.971, p = 0.031). Meta-analysis revealed an association between vasculitis and the IL-10-819 C allele (OR = 0.804, 95% CI = 0.706-0.916, p = 0.001) in all study subjects and Behcet's disease (BD) (OR = 0.724, 95% CI = 0.679-0.781, p vasculitis in all study subjects (OR = 0.805, 95% CI = 0.619-0.938, p = 0.005) and BD (OR = 0.718, 95% CI = 0.661-0.781, p vasculitis in Europeans (OR = 1.239, 95% CI = 1.105-1.513, p = 0.035). This meta-analysis showed that IL-10 polymorphisms are associated with vasculitis susceptibility, especially in WG and BD.

[Review of meta-analysis research on exercise in South Korea].

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Song, Youngshin; Gang, Moonhee; Kim, Sun Ae; Shin, In Soo

2014-10-01

The purpose of this study was to evaluate the quality of meta-analysis regarding exercise using Assessment of Multiple Systematic Reviews (AMSTAR) as well as to compare effect size according to outcomes. Electronic databases including the Korean Studies Information Service System (KISS), the National Assembly Library and the DBpia, HAKJISA and RISS4U for the dates 1990 to January 2014 were searched for 'meta-analysis' and 'exercise' in the fields of medical, nursing, physical therapy and physical exercise in Korea. AMSTAR was scored for quality assessment of the 33 articles included in the study. Data were analyzed using descriptive statistics, t-test, ANOVA and χ²-test. The mean score for AMSTAR evaluations was 4.18 (SD=1.78) and about 67% were classified at the low-quality level and 30% at the moderate-quality level. The scores of quality were statistically different by field of research, number of participants, number of databases, financial support and approval by IRB. The effect size that presented in individual studies were different by type of exercise in the applied intervention. This critical appraisal of meta-analysis published in various field that focused on exercise indicates that a guideline such as the PRISMA checklist should be strongly recommended for optimum reporting of meta-analysis across research fields.

Wind power externalities: A meta-analysis

NARCIS (Netherlands)

Mattmann, M.; Logar, I.; Brouwer, R.

2016-01-01

This study presents the first quantitative meta-analysis of the non-market valuation literature on the external effects associated with wind power production. A data set of 60 observations drawn from 32 studies is constructed. The relative economic values of different types of externalities as well

On the Multilevel Nature of Meta-Analysis: A Tutorial, Comparison of Software Programs, and Discussion of Analytic Choices.

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Pastor, Dena A; Lazowski, Rory A

2018-01-01

The term "multilevel meta-analysis" is encountered not only in applied research studies, but in multilevel resources comparing traditional meta-analysis to multilevel meta-analysis. In this tutorial, we argue that the term "multilevel meta-analysis" is redundant since all meta-analysis can be formulated as a special kind of multilevel model. To clarify the multilevel nature of meta-analysis the four standard meta-analytic models are presented using multilevel equations and fit to an example data set using four software programs: two specific to meta-analysis (metafor in R and SPSS macros) and two specific to multilevel modeling (PROC MIXED in SAS and HLM). The same parameter estimates are obtained across programs underscoring that all meta-analyses are multilevel in nature. Despite the equivalent results, not all software programs are alike and differences are noted in the output provided and estimators available. This tutorial also recasts distinctions made in the literature between traditional and multilevel meta-analysis as differences between meta-analytic choices, not between meta-analytic models, and provides guidance to inform choices in estimators, significance tests, moderator analyses, and modeling sequence. The extent to which the software programs allow flexibility with respect to these decisions is noted, with metafor emerging as the most favorable program reviewed.

Electroconvulsive Therapy Added to Non-Clozapine Antipsychotic Medication for Treatment Resistant Schizophrenia: Meta-Analysis of Randomized Controlled Trials.

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Wei Zheng

Full Text Available This meta-analysis of randomized controlled trials (RCTs examined the efficacy and safety of the combination of electroconvulsive therapy (ECT and antipsychotic medication (except for clozapine versus the same antipsychotic monotherapy for treatment-resistant schizophrenia (TRS. Two independent investigators extracted data for a random effects meta-analysis and pre-specified subgroup and meta-regression analyses. Weighted and standard mean difference (WMD/SMD, risk ratio (RR ±95% confidence intervals (CIs, number needed to treat (NNT, and number needed to harm (NNH were calculated. Eleven studies (n = 818, duration = 10.2±5.5 weeks were identified for meta-analysis. Adjunctive ECT was superior to antipsychotic monotherapy regarding (1 symptomatic improvement at last-observation endpoint with an SMD of -0.67 (p<0.00001; I2 = 62%, separating the two groups as early as weeks 1–2 with an SMD of -0.58 (p<0.00001; I2 = 0%; (2 study-defined response (RR = 1.48, p<0.0001 with an NNT of 6 (CI = 4–9 and remission rate (RR = 2.18, p = 0.0002 with an NNT of 8 (CI = 6–16; (3 PANSS positive and general symptom sub-scores at endpoint with a WMD between -3.48 to -1.32 (P = 0.01 to 0.009. Subgroup analyses were conducted comparing double blind/rater-masked vs. open RCTs, those with and without randomization details, and high quality (Jadad≥adadup analyses were Jadad<3 studies. The ECT-antipsychotic combination caused more headache (p = 0.02 with an NNH of 6 (CI = 4–11 and memory impairment (p = 0.001 with an NNH of 3 (CI = 2–5. The use of ECT to augment antipsychotic treatment (clozapine excepted can be an effective treatment option for TRS, with increased frequency of self-reported memory impairment and headache.CRD42014006689 (PROSPERO.

Association between response rates and survival outcomes in patients with newly diagnosed multiple myeloma. A systematic review and meta-regression analysis.

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Mainou, Maria; Madenidou, Anastasia-Vasiliki; Liakos, Aris; Paschos, Paschalis; Karagiannis, Thomas; Bekiari, Eleni; Vlachaki, Efthymia; Wang, Zhen; Murad, Mohammad Hassan; Kumar, Shaji; Tsapas, Apostolos

2017-06-01

We performed a systematic review and meta-regression analysis of randomized control trials to investigate the association between response to initial treatment and survival outcomes in patients with newly diagnosed multiple myeloma (MM). Response outcomes included complete response (CR) and the combined outcome of CR or very good partial response (VGPR), while survival outcomes were overall survival (OS) and progression-free survival (PFS). We used random-effect meta-regression models and conducted sensitivity analyses based on definition of CR and study quality. Seventy-two trials were included in the systematic review, 63 of which contributed data in meta-regression analyses. There was no association between OS and CR in patients without autologous stem cell transplant (ASCT) (regression coefficient: .02, 95% confidence interval [CI] -0.06, 0.10), in patients undergoing ASCT (-.11, 95% CI -0.44, 0.22) and in trials comparing ASCT with non-ASCT patients (.04, 95% CI -0.29, 0.38). Similarly, OS did not correlate with the combined metric of CR or VGPR, and no association was evident between response outcomes and PFS. Sensitivity analyses yielded similar results. This meta-regression analysis suggests that there is no association between conventional response outcomes and survival in patients with newly diagnosed MM. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The relationship between quality of life and methods of delivery: A systematic review and meta-analysis.

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Rezaei, Nazanin; Tavalaee, Zahra; Sayehmiri, Kourosh; Sharifi, Nasibeh; Daliri, Salman

2018-04-01

Some physical, emotional and social changes arise in mothers during the postpartum periods which can affect the quality of life (QOL) of the mother and family. Given the importance of the quality of life in the postpartum period and its influencing factors such as method of delivery, the present study aimed at investigating the relationship between the quality of life and methods of delivery in the world, using a systematic review and meta-analysis method. The present study is a systematic review and meta-analysis on the relationship between aspects of quality of life and method of delivery in the world conducted in Persian and English language articles published by the end of 2015. For this purpose, the databases of Medlib, SID, Scopus, ISI Web of Science, PubMed, Google scholar, Irandoc, Magiran and Iranmedex were searched using key words and their compounds. The results of studies were combined using the random effects model in the meta-analysis. Heterogeneity of studies was assessed using I2 index and Cochran test and data were analyzed using STATA Version 11.1 and SPSS Version 16. Based on the results of the meta-analysis of studies, the aspect of physical functioning had the highest quality of life mean score in women with vaginal delivery: 74.37 (95% CI: 67.7-81) and mental health had the highest QOL mean score in women with cesarean delivery: 65.8 (95% CI: 62.7-69). Also, based on the time elapsed since delivery, mental health had the highest mean score in less than 1 month, 2 months and 4 months' postpartum. Physical pain had the highest mean score 6 months after giving birth, and mental functioning in 8 months after giving birth. The results of the present meta-analysis showed that the mean scores for most dimensions of quality of life in women with vaginal delivery were higher than in women with cesarean delivery.

Curative effects of small incision cataract surgery versus phacoemulsification: a Meta-analysis

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Chang-Jian Yang

2013-08-01

Full Text Available AIM: To evaluate the curative efficacy of small incision cataract surgery(SICSversus phacoemulsification(Phaco.METHODS: A computerized literature search was carried out in Chinese Biomedical Database(CBM, Wanfang Data, VIP and Chinese National Knowledge Infrastructure(CNKIto collect articles published between 1989-2013 concerning the curative efficacy of SICS versus Phaco. The studies were assessed in terms of clinical case-control criteria. Meta-analysis were performed to assess the visual acuity, the complications rates between SICS and Phaco 90 days after surgery. Treatment effects were measured as risk difference(RDbetween SICS and Phaco. Fixed and random effect models were employed to combine results after a heterogeneity test. RESULTS:A total of 8 studies were included in our Meta-analysis. At 90 days postoperative time, there were no significant differences between the two groups at the visual acuity >0.5(P=0.14; and no significant differences on the complications rates of corneal astigmatism, corneal edema, posterior capsular rupture and anterior iris reaction(P>0.05.CONCLUSION: These results suggest that there is no different on the curative effects of SICS and Phaco for cataract.

Curative efficacy and safety of traditional Chinese medicine xuebijing injections combined with ulinastatin for treating sepsis in the Chinese population: A meta-analysis.

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Xiao, Shi-Hui; Luo, Liang; Liu, Xiang-Hong; Zhou, Yu-Ming; Liu, Hong-Ming; Huang, Zhen-Fei

2018-06-01

Sepsis is a clinically critical disease. However, it is still controversial whether the combined use of traditional Chinese medicine Xuebijing injections (XBJI) and western medicine can enhance curative efficacy and ensure safety compared with western medicine alone. Thus, this research consisted of a systematic review of the curative efficacy and safety of traditional Chinese medicine XBJI combined with ulinastatin for treating sepsis in the Chinese population. A total of 8 databases were retrieved: 4 foreign databases, namely, PubMed, The Cochrane Library, Embase, and Web of Science; and 4 Chinese databases, namely, Sino Med, China National Knowledge Infrastructure (CNKI), VIP, and Wangfang Data. The time span of retrieval began from the establishment of each database and ended on August 1, 2017. Published randomized controlled trials about the combined use of traditional Chinese medicine XBJI and western medicine were included, regardless of language. Stata12.0 software was used for statistical analysis. Finally, 16 papers involving 1335 cases were included. The result of meta-analysis showed that compared with the single use of ulinastatin, traditional Chinese medicine XBJI combined with ulinastatin could reduce the time of mechanical ventilation, shorten the length of intensive care unit (ICU) stay, improve the 28-day survival rate, and decrease the occurrence rate of multiple organ dysfunction syndrome, case fatality rate, procalcitonin (PCT) content, APACKEII score, tumor necrosis factor (TNF)-α level, and interleukin (IL)-6 level. On the basis of the common basic therapeutic regimen, the combined use of traditional Chinese medicine XBJI and ulinastatin was compared with the use of ulinastatin alone for treating sepsis in the Chinese population. It was found that the number of adverse events of combination therapy is not significantly increased, and its clinical safety is well within the permitted range. However, considering the limitations of this

Reevaluation of Meta-analysis on prophylactic drug management for recurrence of febrile seizures

Directory of Open Access Journals (Sweden)

Huan LIAO

2015-08-01

Full Text Available Objective To explore the efficiency and safety of drugs to prevent the recurrence of febrile seizures (FS.  Methods Relevant literatures were searched via PubMed, EMBASE/SCOPUS, EBSCO-CINAHL, Web of Science, Cochrane Database of Systematic Reviews from December 1997 to November 2014 using the following keywords: febrile seizure OR febrile convulsion, recurrence, prevention OR prophylaxis, medicine OR medication. Publication type was limited to Meta-analysis. Extract the relevant information of Meta-analysis, such as characteristics of objects, types of study design, number of clinical trials, number of cases, search strategies, databases, information of methodology (methods of randomization, concealment, blinding, withdrawal and exit, follow-up time, heterogeneity analysis, subgroup analysis and outcome assessment, etc. Quality of Reporting of Meta-analyses (QUOROM and Oxman-Guyatt Overview Quality Assessment Questionnaire (OQAQ were used to assess the quality of included Meta-analyses. Jadad decision was used to assess inclusion and exclusion criteria, search strategies, effectiveness evaluation, data extraction and data analysis, to explore reliable evidence of evidence-based medicine.  Results Eventually, four Meta-analyses were included after screening of all the literatures that can be searched out. Among those Meta-analyses, the Meta-analysis of Offringa and Newton (2012 was relatively more reliable. The results suggesed that no clinically important benefits were found in administering intermittent oral or rectal diazepam, oral phenobarbitone, phenytoin, valproate, pyridoxine, buprofen, diclofenac and acetominophen to children with FE. Only one clinical trial reported that intermittent oral clobazam could reduce the recurrence of FE in comparing with placebo at 6-month follow-up (RR = 0.360, 95% CI: 0.200-0.640; P = 0.000, but it should be verified by more randomized controlled trials (RCTs. Among 4 Meta-analyses included in this study

Immune checkpoint inhibitors and targeted therapies for metastatic melanoma: A network meta-analysis.

Science.gov (United States)

Pasquali, Sandro; Chiarion-Sileni, Vanna; Rossi, Carlo Riccardo; Mocellin, Simone

2017-03-01

Immune checkpoint inhibitors and targeted therapies, two new class of drugs for treatment of metastatic melanoma, have not been compared in randomized controlled trials (RCT). We quantitatively summarized the evidence and compared immune and targeted therapies in terms of both efficacy and toxicity. A comprehensive search for RCTs of immune checkpoint inhibitors and targeted therapies was conducted to August 2016. Using a network meta-analysis approach, treatments were compared with each other and ranked based on their effectiveness (as measured by the impact on progression-free survival [PFS]) and acceptability (the inverse of high grade toxicity). Twelve RCTs enrolling 6207 patients were included. Network meta-analysis generated 15 comparisons. Combined BRAF and MEK inhibitors were associated with longer PFS as compared to anti-CTLA4 (HR: 0.22; 95% confidence interval [CI]: 0.12-0.41) and anti-PD1 antibodies alone (HR: 0.38; CI: 0.20-0.72). However, anti-PD1 monoclonal antibodies were less toxic than anti-CTLA4 monoclonal antibodies (RR: 0.65; CI: 0.40-0.78) and their combination significantly increased toxicity compared to either single agent anti-CTLA4 (RR: 2.06; CI: 1.45-2.93) or anti-PD1 monoclonal antibodies (RR: 3.67; CI: 2.27-5.96). Consistently, ranking analysis suggested that the combination of targeted therapies is the most effective strategy, whereas single agent anti-PD1 antibodies have the best acceptability. The GRADE level of evidence quality for these findings was moderate to low. The simultaneous inhibition of BRAF and MEK appears the most effective treatment for melanomas harboring BRAF V600 mutation, although anti-PD1 antibodies appear to be less toxic. Further research is needed to increase the quality of evidence. Copyright © 2017 Elsevier Ltd. All rights reserved.

Systematic review and meta-analysis of glyphosate exposure and risk of lymphohematopoietic cancers.

Science.gov (United States)

Chang, Ellen T; Delzell, Elizabeth

2016-01-01

This systematic review and meta-analysis rigorously examines the relationship between glyphosate exposure and risk of lymphohematopoietic cancer (LHC) including NHL, Hodgkin lymphoma (HL), multiple myeloma (MM), and leukemia. Meta-relative risks (meta-RRs) were positive and marginally statistically significant for the association between any versus no use of glyphosate and risk of NHL (meta-RR = 1.3, 95% confidence interval (CI) = 1.0-1.6, based on six studies) and MM (meta-RR = 1.4, 95% CI = 1.0-1.9; four studies). Associations were statistically null for HL (meta-RR = 1.1, 95% CI = 0.7-1.6; two studies), leukemia (meta-RR = 1.0, 95% CI = 0.6-1.5; three studies), and NHL subtypes except B-cell lymphoma (two studies each). Bias and confounding may account for observed associations. Meta-analysis is constrained by few studies and a crude exposure metric, while the overall body of literature is methodologically limited and findings are not strong or consistent. Thus, a causal relationship has not been established between glyphosate exposure and risk of any type of LHC.

Poor Gait Performance and Prediction of Dementia: Results From a Meta-Analysis.

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Beauchet, Olivier; Annweiler, Cédric; Callisaya, Michele L; De Cock, Anne-Marie; Helbostad, Jorunn L; Kressig, Reto W; Srikanth, Velandai; Steinmetz, Jean-Paul; Blumen, Helena M; Verghese, Joe; Allali, Gilles

2016-06-01

Poor gait performance predicts risk of developing dementia. No structured critical evaluation has been conducted to study this association yet. The aim of this meta-analysis was to systematically examine the association of poor gait performance with incidence of dementia. An English and French Medline search was conducted in June 2015, with no limit of date, using the medical subject headings terms "Gait" OR "Gait Disorders, Neurologic" OR "Gait Apraxia" OR "Gait Ataxia" AND "Dementia" OR "Frontotemporal Dementia" OR "Dementia, Multi-Infarct" OR "Dementia, Vascular" OR "Alzheimer Disease" OR "Lewy Body Disease" OR "Frontotemporal Dementia With Motor Neuron Disease" (Supplementary Concept). Poor gait performance was defined by standardized tests of walking, and dementia was diagnosed according to international consensus criteria. Four etiologies of dementia were identified: any dementia, Alzheimer disease (AD), vascular dementia (VaD), and non-AD (ie, pooling VaD, mixed dementias, and other dementias). Fixed effects meta-analyses were performed on the estimates in order to generate summary values. Of the 796 identified abstracts, 12 (1.5%) were included in this systematic review and meta-analysis. Poor gait performance predicted dementia [pooled hazard ratio (HR) combined with relative risk and odds ratio = 1.53 with P analysis provides evidence that poor gait performance predicts dementia. This association depends on the type of dementia; poor gait performance is a stronger predictor of non-AD dementias than AD. Copyright © 2016 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.

Meniscal allograft transplantation: a meta-analysis

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De Bruycker Manolito

2017-01-01

Full Text Available Purpose: This meta-analysis evaluates the mid- to long-term survival outcome of MAT (meniscal allograft transplantation. Potential prognosticators, with particular focus on chondral status and age of the patient at the time of transplantation, were also analysed. Study design: Meta-analysis. Methods: An online database search was performed using following search string: “meniscal allograft transplantation” and “outcome”. A total of 65 articles were analysed for a total of 3157 performed MAT with a mean follow-up of 5.4 years. Subjective and clinical data was analysed. Results: The subjective and objective results of 2977 patients (3157 allografts were analysed; 70% were male, 30% were female. Thirty-eight percent received an isolated MAT. All other patients underwent at least one concomitant procedure. Lysholm, Knee injury and Osteoarthritis Outcome (KOOS, International Knee Documentation Committee (IKDC and Visual Analogue Scale (VAS scores were analysed. All scores showed a good patient satisfaction at long-term follow-up. The mean overall survival rate was 80.9%. Complication rates were comparable to standard meniscal repair surgery. There was a degenerative evolution in osteoarthritis with at least one grade in 1760 radiographically analysed patients. Concomitant procedures seem to have no effect on the outcome. Age at transplantation is a negative prognosticator. The body mass index (BMI of the patient shows a slightly negative correlation with the outcome of MAT. Conclusions: MAT is a viable solution for the younger patient with chronic pain in the meniscectomised knee joint. The complications are not severe and comparable to meniscal repair. The overall failure rate at final follow-up is acceptable and the allograft heals well in most cases, but MAT cannot be seen as a definitive solution for post-meniscectomy pain. The correct approach to the chronic painful total meniscectomised knee joint thus requires consideration of all

Child Wasting in Emergency Pockets: A Meta-Analysis of Small-Scale Surveys from Ethiopia

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Chiara Altare

2016-01-01

Full Text Available Child undernutrition is a major public health concern in Ethiopia (stunting national prevalence: 44%; wasting: 10%, despite the overall improvement in child health status during the last decade. Hundreds of small-scale surveys are conducted in Ethiopia’s emergency pockets under ENCU’s supervision. We reviewed the evidence from small-scale surveys conducted between 2008 and 2013 with two objectives: to provide a summary estimate of wasting prevalence from emergency pockets and to examine reasons for variation in prevalence estimates. We created a dataset by combining data from the Complex Emergency Database, the Famine Early Warning System Network and the Armed Conflict Location Event Data. We conducted a meta-analysis of small-scale surveys using a random effects model with known within-study heterogeneity. The influence of survey covariates on estimated prevalence was investigated with meta-regression techniques. We included 158 surveys in the analysis. A high degree of heterogeneity among surveys was observed. The overall estimate of wasting prevalence was 10.6% (95% CI 9.8–11.4, with differences among regions and between residents and refugees. Meta-regression results showed that vaccination coverage, child mortality, diarrhea prevalence and food insecurity are significantly associated with wasting prevalence. Child care and displacement status were not. Aggregated analysis of small-scale surveys provides insights into the prevalence of wasting and factors explaining its variation. It can also guide survey planning towards areas with limited data availability.

Values of natural and human-made wetlands: A meta-analysis

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Ghermandi, A.; van den Bergh, J.C.J.M.; Brander, L.M.; de Groot, H.L.F.; Nunes, P.A.L.D.

2010-01-01

The values of goods and services provided by wetland ecosystems are examined through a meta-analysis of an expanded database of wetland value estimates and with a focus on human-made wetlands. This study extends and improves upon previous meta-analyses of the wetland valuation literature in terms of

A Healthy Dietary Pattern Reduces Lung Cancer Risk: A Systematic Review and Meta-Analysis

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Yanlai Sun

2016-03-01

Full Text Available Background: Diet and nutrients play an important role in cancer development and progress; a healthy dietary pattern has been found to be associated with several types of cancer. However, the association between a healthy eating pattern and lung cancer risk is still unclear. Objective: Therefore, we conducted a systematic review with meta-analysis to evaluate whether a healthy eating pattern might reduce lung cancer risk. Methods: We identified relevant studies from the PubMed and Embase databases up to October 2015, and the relative risks were extracted and combined by the fixed-effects model when no substantial heterogeneity was observed; otherwise, the random-effects model was employed. Subgroup and publication bias analyses were also performed. Results: Finally, eight observational studies were included in the meta-analysis. The pooled relative risk of lung cancer for the highest vs. lowest category of healthy dietary pattern was 0.81 (95% confidence interval, CI: 0.75–0.86, and no significant heterogeneity was detected. The relative risks (RRs for non-smokers, former smokers and current smokers were 0.89 (95% CI: 0.63–1.27, 0.74 (95% CI: 0.62–0.89 and 0.86 (95% CI: 0.79–0.93, respectively. The results remained stable in subgroup analyses by other confounders and sensitivity analysis. Conclusions: The results of our meta-analysis suggest that a healthy dietary pattern is associated with a lower lung cancer risk, and they provide more beneficial evidence for changing the diet pattern in the general population.

Prevalence of treponema species detected in endodontic infections: systematic review and meta-regression analysis.

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Leite, Fábio R M; Nascimento, Gustavo G; Demarco, Flávio F; Gomes, Brenda P F A; Pucci, Cesar R; Martinho, Frederico C

2015-05-01

This systematic review and meta-regression analysis aimed to calculate a combined prevalence estimate and evaluate the prevalence of different Treponema species in primary and secondary endodontic infections, including symptomatic and asymptomatic cases. The MEDLINE/PubMed, Embase, Scielo, Web of Knowledge, and Scopus databases were searched without starting date restriction up to and including March 2014. Only reports in English were included. The selected literature was reviewed by 2 authors and classified as suitable or not to be included in this review. Lists were compared, and, in case of disagreements, decisions were made after a discussion based on inclusion and exclusion criteria. A pooled prevalence of Treponema species in endodontic infections was estimated. Additionally, a meta-regression analysis was performed. Among the 265 articles identified in the initial search, only 51 were included in the final analysis. The studies were classified into 2 different groups according to the type of endodontic infection and whether it was an exclusively primary/secondary study (n = 36) or a primary/secondary comparison (n = 15). The pooled prevalence of Treponema species was 41.5% (95% confidence interval, 35.9-47.0). In the multivariate model of meta-regression analysis, primary endodontic infections (P apical abscess, symptomatic apical periodontitis (P < .001), and concomitant presence of 2 or more species (P = .028) explained the heterogeneity regarding the prevalence rates of Treponema species. Our findings suggest that Treponema species are important pathogens involved in endodontic infections, particularly in cases of primary and acute infections. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

REAL-TIME ENERGY INFORMATION AND CONSUMER BEHAVIOR: A META-ANALYSIS AND FORECAST

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The meta-analysis of literature and program results will shed light on potential causes of study-to-study variation in information feedback programs and trials. Outputs from the meta-analysis, such as price elasticity, will be used in NEMS to estimate the impact of a nation...

Transcriptome Analysis of Sunflower Genotypes with Contrasting Oxidative Stress Tolerance Reveals Individual- and Combined- Biotic and Abiotic Stress Tolerance Mechanisms.

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Vemanna S Ramu

Full Text Available In nature plants are often simultaneously challenged by different biotic and abiotic stresses. Although the mechanisms underlying plant responses against single stress have been studied considerably, plant tolerance mechanisms under combined stress is not understood. Also, the mechanism used to combat independently and sequentially occurring many number of biotic and abiotic stresses has also not systematically studied. From this context, in this study, we attempted to explore the shared response of sunflower plants to many independent stresses by using meta-analysis of publically available transcriptome data and transcript profiling by quantitative PCR. Further, we have also analyzed the possible role of the genes so identified in contributing to combined stress tolerance. Meta-analysis of transcriptomic data from many abiotic and biotic stresses indicated the common representation of oxidative stress responsive genes. Further, menadione-mediated oxidative stress in sunflower seedlings showed similar pattern of changes in the oxidative stress related genes. Based on this a large scale screening of 55 sunflower genotypes was performed under menadione stress and those contrasting in oxidative stress tolerance were identified. Further to confirm the role of genes identified in individual and combined stress tolerance the contrasting genotypes were individually and simultaneously challenged with few abiotic and biotic stresses. The tolerant hybrid showed reduced levels of stress damage both under combined stress and few independent stresses. Transcript profiling of the genes identified from meta-analysis in the tolerant hybrid also indicated that the selected genes were up-regulated under individual and combined stresses. Our results indicate that menadione-based screening can identify genotypes not only tolerant to multiple number of individual biotic and abiotic stresses, but also the combined stresses.

Impact of Instructional Decisions on the Effectiveness of Cooperative Learning in Chemistry through Meta-Analysis

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Apugliese, Andrew; Lewis, Scott E.

2017-01-01

Meta-analysis can provide a robust description of the impact of educational reforms and also offer an opportunity to explore the conditions where such reforms are more or less effective. This article describes a meta-analysis on the impact of cooperative learning on students' chemistry understanding. Modifiers in the meta-analysis are purposefully…

Corticosteroids vs corticosteroids plus antiviral agents in the treatment of Bell palsy: a systematic review and meta-analysis.

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Goudakos, John K; Markou, Konstantinos D

2009-06-01

To review systematically and meta-analyze the results of all randomized controlled trials (RCTs) for the treatment of patients with Bell palsy with corticosteroids vs corticosteroids plus antiviral agents. A MEDLINE, EMBASE, Cochrane Library, and CENTRAL database search, followed by extensive hand-searching for the identification of relevant studies. No time and language limitations were applied. Prospective RCTs on the treatment of patients with Bell palsy. Odds ratios (ORs), 95% confidence intervals (CIs), and tests for heterogeneity were reported. Five studies were eventually identified and systematically reviewed. Meta-analysis was performed for 4 studies. Regarding the complete recovery rate of facial nerve paralysis 3 months after initiation of therapy, the current systematic review and meta-analysis suggests that the addition of an antiviral agent does not provide any benefit (OR, 1.03 [95% CI, 0.74-1.42]; P = .88). The same conclusion emerged at posterior (fourth, sixth, and ninth) months of assessment. Subgroup analysis, conducted on the basis of time point of therapy initiation, type of antiviral agent, and blindness of assessments did not change the results obtained. The occurrence rate of adverse effects attributable to therapy choice was not significantly different between patients receiving corticosteroids and those following combined treatment. The present systematic review and meta-analysis, based on the currently available evidence, suggests that the addition of an antiviral agent to corticosteroids for the treatment of Bell palsy is not associated with an increase in the complete recovery rate of the facial motor function.

Serum Uric Acid Levels and Diabetic Peripheral Neuropathy in Type 2 Diabetes: a Systematic Review and Meta-analysis.

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Yu, Shuai; Chen, Ying; Hou, Xu; Xu, Donghua; Che, Kui; Li, Changgui; Yan, Shengli; Wang, Yangang; Wang, Bin

2016-03-01

Previous studies suggested a possible association between serum uric acid levels and peripheral neuropathy in patients with type 2 diabetes, but no definite evidence was available. A systematic review and meta-analysis of relevant studies were performed to comprehensively estimate the association. Pubmed, Web of Science, Embase, and China Biology Medicine (CBM) databases were searched for eligible studies. Study-specific data were combined using random-effect or fixed-effect models of meta-analysis according to between-study heterogeneity. Twelve studies were finally included into the meta-analysis, which involved a total of 1388 type 2 diabetic patients with peripheral neuropathy and 4746 patients without peripheral neuropathy. Meta-analysis showed that there were obvious increased serum uric acid levels in diabetic patients with peripheral neuropathy (weighted mean difference [WMD] = 50.03 μmol/L, 95% confidence interval [95%CI] 22.14-77.93, P = 0.0004). Hyperuricemia was also significantly associated with increased risk of peripheral neuropathy in patients with type 2 diabetes (risk ratio [RR] = 2.83, 95%CI 2.13-3.76, P peripheral neuropathy in type 2 diabetic patients (RR = 1.95, 95%CI 1.23-3.11, P = 0.005). Type 2 diabetic patients with peripheral neuropathy have obvious increased serum uric acid levels, and hyperuricemia is associated with increased risk of peripheral neuropathy. Further prospective cohort studies are needed to validate the impact of serum uric acid levels on peripheral neuropathy risk.

ABO blood group and esophageal carcinoma risk: from a case-control study in Chinese population to meta-analysis.

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Wang, Wei; Liu, Lei; Wang, Zhiwei; Lu, Xiaopeng; Wei, Min; Lin, Tianlong; Zhang, Yixin; Jiang, Songqi; Wang, Qiang; Cao, Ziang; Shi, Minxin

2014-10-01

The association between ABO blood group and the risk of esophageal carcinoma (EC) in previously published studies is uncertain and conflicting. The aim of the current study was to determine the correlation of ABO blood group with EC risk via a case-control study and meta-analysis. We performed a population-based case-control study of 3,595 cases and 41,788 controls in Chinese population to evaluate the association between ABO blood group and EC risk. Then, a comprehensive meta-analysis combining our original data and previously published data was conducted to clearly discern the real relationship. The strength of association was measured by odds ratios (ORs) with 95% confidence intervals (CI). In our case-control study, the risk of EC in blood group B was significantly higher than that in non-B groups (A, O, and AB) (OR = 1.15, 95% CI 1.09-1.21). Compared with non-O groups (A, B, and AB), individuals with blood group O demonstrated a reduced risk of EC (OR = 0.90, 95% CI 0.85-0.94). The meta-analysis also indicated that blood group B was associated with significantly higher EC risk (OR = 1.20, 95% CI 1.10-1.31), and people with blood group O had a decreased EC risk (OR = 0.94, 95% CI 0.90-0.99). Neither the case-control study nor the meta-analysis produced any significant association of blood group A or AB with EC risk. Results from our case-control study and the followed meta-analysis confirmed that there was an increased risk of EC in blood group B individuals, whereas a decreased risk of EC was observed in blood group O individuals.

Using beta coefficients to impute missing correlations in meta-analysis research: Reasons for caution.

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Roth, Philip L; Le, Huy; Oh, In-Sue; Van Iddekinge, Chad H; Bobko, Philip

2018-06-01

Meta-analysis has become a well-accepted method for synthesizing empirical research about a given phenomenon. Many meta-analyses focus on synthesizing correlations across primary studies, but some primary studies do not report correlations. Peterson and Brown (2005) suggested that researchers could use standardized regression weights (i.e., beta coefficients) to impute missing correlations. Indeed, their beta estimation procedures (BEPs) have been used in meta-analyses in a wide variety of fields. In this study, the authors evaluated the accuracy of BEPs in meta-analysis. We first examined how use of BEPs might affect results from a published meta-analysis. We then developed a series of Monte Carlo simulations that systematically compared the use of existing correlations (that were not missing) to data sets that incorporated BEPs (that impute missing correlations from corresponding beta coefficients). These simulations estimated ρ̄ (mean population correlation) and SDρ (true standard deviation) across a variety of meta-analytic conditions. Results from both the existing meta-analysis and the Monte Carlo simulations revealed that BEPs were associated with potentially large biases when estimating ρ̄ and even larger biases when estimating SDρ. Using only existing correlations often substantially outperformed use of BEPs and virtually never performed worse than BEPs. Overall, the authors urge a return to the standard practice of using only existing correlations in meta-analysis. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

A Meta-Analysis of Maternal Smoking during Pregnancy and Autism Spectrum Disorder Risk in Offspring

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Shiming Tang

2015-08-01

Full Text Available The association between maternal smoking during pregnancy and autism spectrum disorder (ASD risk in offspring has been investigated in several studies, but the evidence is not conclusive. We, therefore, conducted this meta-analysis to explore whether an association exists between maternal smoking during pregnancy and ASD risk in offspring. We searched PubMed, Embase, Web of Science, and the Cochrane Library for studies of maternal smoking during pregnancy and ASD risk in offspring up to 10 June 2015. The random-effects model was used to combine results from individual studies. 15 observational studies (6 cohort studies and 9 case-control studies, with 17,890 ASD cases and 1,810,258 participants were included for analysis. The pooled odds ratio (OR was 1.02 (95% confidence interval (CI: 0.93–1.13 comparing mothers who smoked during pregnancy with those who did not. Subgroup and sensitivity analysis suggested the overall result of this analysis was robust. Results from this meta-analysis indicate that maternal smoking during pregnancy is not associated with ASD risk in offspring. Further well-designed cohort studies are needed to confirm the present findings.

A Microsoft-Excel-based tool for running and critically appraising network meta-analyses--an overview and application of NetMetaXL.

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Brown, Stephen; Hutton, Brian; Clifford, Tammy; Coyle, Doug; Grima, Daniel; Wells, George; Cameron, Chris

2014-09-29

The use of network meta-analysis has increased dramatically in recent years. WinBUGS, a freely available Bayesian software package, has been the most widely used software package to conduct network meta-analyses. However, the learning curve for WinBUGS can be daunting, especially for new users. Furthermore, critical appraisal of network meta-analyses conducted in WinBUGS can be challenging given its limited data manipulation capabilities and the fact that generation of graphical output from network meta-analyses often relies on different software packages than the analyses themselves. We developed a freely available Microsoft-Excel-based tool called NetMetaXL, programmed in Visual Basic for Applications, which provides an interface for conducting a Bayesian network meta-analysis using WinBUGS from within Microsoft Excel. . This tool allows the user to easily prepare and enter data, set model assumptions, and run the network meta-analysis, with results being automatically displayed in an Excel spreadsheet. It also contains macros that use NetMetaXL's interface to generate evidence network diagrams, forest plots, league tables of pairwise comparisons, probability plots (rankograms), and inconsistency plots within Microsoft Excel. All figures generated are publication quality, thereby increasing the efficiency of knowledge transfer and manuscript preparation. We demonstrate the application of NetMetaXL using data from a network meta-analysis published previously which compares combined resynchronization and implantable defibrillator therapy in left ventricular dysfunction. We replicate results from the previous publication while demonstrating result summaries generated by the software. Use of the freely available NetMetaXL successfully demonstrated its ability to make running network meta-analyses more accessible to novice WinBUGS users by allowing analyses to be conducted entirely within Microsoft Excel. NetMetaXL also allows for more efficient and transparent

A Microsoft-Excel-based tool for running and critically appraising network meta-analyses—an overview and application of NetMetaXL

Science.gov (United States)

2014-01-01

Background The use of network meta-analysis has increased dramatically in recent years. WinBUGS, a freely available Bayesian software package, has been the most widely used software package to conduct network meta-analyses. However, the learning curve for WinBUGS can be daunting, especially for new users. Furthermore, critical appraisal of network meta-analyses conducted in WinBUGS can be challenging given its limited data manipulation capabilities and the fact that generation of graphical output from network meta-analyses often relies on different software packages than the analyses themselves. Methods We developed a freely available Microsoft-Excel-based tool called NetMetaXL, programmed in Visual Basic for Applications, which provides an interface for conducting a Bayesian network meta-analysis using WinBUGS from within Microsoft Excel. . This tool allows the user to easily prepare and enter data, set model assumptions, and run the network meta-analysis, with results being automatically displayed in an Excel spreadsheet. It also contains macros that use NetMetaXL’s interface to generate evidence network diagrams, forest plots, league tables of pairwise comparisons, probability plots (rankograms), and inconsistency plots within Microsoft Excel. All figures generated are publication quality, thereby increasing the efficiency of knowledge transfer and manuscript preparation. Results We demonstrate the application of NetMetaXL using data from a network meta-analysis published previously which compares combined resynchronization and implantable defibrillator therapy in left ventricular dysfunction. We replicate results from the previous publication while demonstrating result summaries generated by the software. Conclusions Use of the freely available NetMetaXL successfully demonstrated its ability to make running network meta-analyses more accessible to novice WinBUGS users by allowing analyses to be conducted entirely within Microsoft Excel. NetMetaXL also allows

Combining risk estimates from observational studies with different exposure cutpoints: a meta-analysis on body mass index and diabetes type 2.

NARCIS (Netherlands)

Hartemink, Nienke; Boshuizen, Hendriek C; Nagelkerke, Nico J D; Jacobs, Monique A M; Houwelingen, Hans C van

2006-01-01

Studies on a dose-response relation often report separate relative risks for several risk classes compared with a referent class. When performing a meta-analysis of such studies, one has to convert these relative risks into an overall relative risk for a continuous effect. Apart from taking the

Global meta-analysis of transcriptomics studies.

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José Caldas

Full Text Available Transcriptomics meta-analysis aims at re-using existing data to derive novel biological hypotheses, and is motivated by the public availability of a large number of independent studies. Current methods are based on breaking down studies into multiple comparisons between phenotypes (e.g. disease vs. healthy, based on the studies' experimental designs, followed by computing the overlap between the resulting differential expression signatures. While useful, in this methodology each study yields multiple independent phenotype comparisons, and connections are established not between studies, but rather between subsets of the studies corresponding to phenotype comparisons. We propose a rank-based statistical meta-analysis framework that establishes global connections between transcriptomics studies without breaking down studies into sets of phenotype comparisons. By using a rank product method, our framework extracts global features from each study, corresponding to genes that are consistently among the most expressed or differentially expressed genes in that study. Those features are then statistically modelled via a term-frequency inverse-document frequency (TF-IDF model, which is then used for connecting studies. Our framework is fast and parameter-free; when applied to large collections of Homo sapiens and Streptococcus pneumoniae transcriptomics studies, it performs better than similarity-based approaches in retrieving related studies, using a Medical Subject Headings gold standard. Finally, we highlight via case studies how the framework can be used to derive novel biological hypotheses regarding related studies and the genes that drive those connections. Our proposed statistical framework shows that it is possible to perform a meta-analysis of transcriptomics studies with arbitrary experimental designs by deriving global expression features rather than decomposing studies into multiple phenotype comparisons.

Dacron® vs. PTFE as bypass materials in peripheral vascular surgery – systematic review and meta-analysis

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Roll, Stephanie; Müller-Nordhorn, Jacqueline; Keil, Thomas; Scholz, Hans; Eidt, Daniela; Greiner, Wolfgang; Willich, Stefan N

2008-01-01

Background In peripheral vascular bypass surgery different synthetic materials are available for bypass grafting. It is unclear which of the two commonly used materials, polytetrafluoroethylene (PTFE) or polyester (Dacron®) grafts, is to be preferred. Thus, the aim of this meta-analysis and systematic review was to compare the effectiveness of these two prosthetic bypass materials (Dacron® and PTFE). Methods We performed a systematic literature search in MEDLINE, Cochrane-Library – CENTRAL, EMBASE and other databases for relevant publications in English and German published between 1999 and 2008. Only randomized controlled trials were considered for inclusion. We assessed the methodological quality by means of standardized checklists. Primary patency was used as the main endpoint. Random-effect meta-analysis as well as pooling data in life table format was performed to combine study results. Results Nine randomized controlled trials (RCT) were included. Two trials showed statistically significant differences in primary patency, one favouring Dacron® and one favouring PTFE grafts, while 7 trials did not show statistically significant differences between the two materials. Meta-analysis on the comparison of PTFE vs. Dacron® grafts yielded no differences with regard to primary patency rates (hazard ratio 1.04 (95% confidence interval [0.85;1.28]), no significant heterogeneity (p = 0.32, I2 = 14%)). Similarly, there were no significant differences with regard to secondary patency rates. Conclusion Systematic evaluation and meta-analysis of randomized controlled trials comparing Dacron® and PTFE as bypass materials for peripheral vascular surgery showed no evidence of an advantage of one synthetic material over the other. PMID:19099583

Testosterone level and risk of type 2 diabetes in men: a systematic review and meta-analysis

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Qiu-ming Yao

2018-01-01

Full Text Available Background: Type 2 diabetes is a risk factor for testosterone deficiency and impaired sex steroid status. Some studies also investigated the association of testosterone level with diabetes risk in men, but reported controversial findings. To clarify this issue, we conducted a systematic review and meta-analysis. Methods: PubMed, EMBASE and Web of Science were searched for eligible cohort or nested case–control studies published up to August 15, 2017. Meta-analysis was used to calculate the pooled relative risk (RR of type 2 diabetes associated with higher testosterone level. Results: Thirteen cohort or nested case–control studies with 16,709 participants were included. Meta-analysis showed that higher total testosterone level could significantly decrease the risk of type 2 diabetes in men (RR = 0.65; 95% CI 0.50–0.84; P = 0.001, and higher free testosterone level could also decrease the risk of type 2 diabetes in men (RR = 0.94; 95% CI 0.90–0.99; P = 0.014. After excluding two studies that did not calculate RRs by quartiles of testosterone levels, both higher total testosterone and free testosterone levels could decrease the risk of type 2 diabetes in men, and the pooled RRs were 0.62 (95% CI 0.51–0.76; P < 0.001 and 0.77 (95% CI 0.61–0.98; P = 0.03, respectively. Conclusion: This meta-analysis suggests that higher testosterone level can significantly decrease the risk of type 2 diabetes in men. Therefore, combined with previous researches, the findings above suggest a reverse-causality scenario in the relation between testosterone deficiency and risk of type 2 diabetes in men.

Mental health and public policies implemented in the Northeast of Brazil: A systematic review with meta-analysis.

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Januário, Sonilde Saraiva; das Neves Peixoto, Florido Sampaio; Lima, Nádia Nara Rolim; do Nascimento, Vânia Barbosa; de Sousa, Danilo Ferreira; Pereira Luz, Dayse Christina Rodrigues; da Silva, Claúdio Gleidiston Lima; Rolim Neto, Modesto Leite

2017-02-01

Studies about mental disorders are very rare in the Northeast of Brazil, especially when psychopathologies in children and adolescents are considered. The consequence is a small availability of data and an absence of a real epidemiological profile. This is a systematic review with meta-analysis, following the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) protocol, in the period from 2003 to 2015, using the databases LILACS, SciELO and BVS. The analysis comprised the keywords 'models of primary and secondary healthcare in mental health', 'psychiatric reform' and 'policies and services in mental health', using the Boolean operator '# AND'. Original texts based on secondary data from the Hospital Information System of the Brazilian Unified Health System were also included via the Citizen Electronic Record System, Instituto Brasileiro de Geografia e Estatística, and Ministry of Health. Grey literature was used by means of hand searching. A combined analysis of the strategies mentioned in the analyzed articles shows a combined odds ratio of 1.291 (confidence interval (CI) = 1.054-1.582), thus it demonstrates the efficacy of using such strategies in the elaboration of institutional apparatus in mental health. The p-value of the chi-square distribution resulted in .9753, which does not reject the hypothesis of association between strategies in mental health and possible development of institutional apparatus in mental health. A combined analysis of all strategies mentioned in the analyzed studies shows efficacy of using strategies to elaborate institutional apparatus in mental health.

Dietary patterns and colorectal cancer risk: a meta-analysis.

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Feng, Yu-Liang; Shu, Long; Zheng, Pei-Fen; Zhang, Xiao-Yan; Si, Cai-Juan; Yu, Xiao-Long; Gao, Wei; Zhang, Lun

2017-05-01

The analysis of dietary patterns has recently drawn considerable attention as a method of investigating the association between the overall whole diet and the risk of colorectal cancer. However, the results have yielded conflicting findings. Here, we carried out a meta-analysis to identify the association between dietary patterns and the risk of colorectal cancer. A total of 40 studies fulfilled the inclusion criteria and were included in this meta-analysis. The highest category of 'healthy' dietary pattern compared with the lowest category was apparently associated with a decreased risk for colorectal cancer [odds ratio (OR)=0.75; confidence interval (CI): 0.68-0.83; Pcolorectal cancer was shown for the highest compared with the lowest category of a 'western-style' dietary pattern (OR=1.40; CI: 1.26-1.56; Pcolorectal cancer in the highest compared with the lowest category of 'alcohol-consumption' pattern (OR=1.44; CI: 1.13-1.82; P=0.003). The results of this meta-analysis indicate that a 'healthy' dietary pattern may decrease the risk of colorectal cancer, whereas 'western-style' and 'alcohol-consumption' patterns may increase the risk of colorectal cancer.

Abreaction for conversion disorder: systematic review with meta-analysis.

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Poole, Norman A; Wuerz, Axel; Agrawal, Niruj

2010-08-01

The value of drug interviews in the treatment of conversion disorder is at present unknown. To review all the available papers published in English that report on the use of drug interviews for treating conversion/dissociative disorder. Databases (including EMBASE, MEDLINE and PsycINFO) were searched from 1920 to 2009. Selected publications had to report on the use of drug interviews in people diagnosed with a conversion/dissociative disorder. Qualitative and quantitative data were extracted. Predictors of a positive response were ascertained using meta-analytic techniques. Fifty-five papers meeting inclusion criteria were identified. No studies compared the intervention with a suitable control group. However, two studies reported high response rates when drug interview was used in individuals with treatment-resistant conversion disorder. In the meta-analysis, the use of suggestion and occurrence of emotional catharsis during the interview were positively associated with recovery. Combining two medications and comorbid psychiatric disorder were negatively associated with recovery. The evidence for effectiveness of drug interviews is of poor quality but it may be of benefit in the treatment of acute and treatment-resistant conversion disorder. A proactive approach during the interview, making suggestions the individual will respond, could influence outcome. Comorbid psychiatric disorder should be treated conventionally. Experimental studies to determine efficacy are required.

Development and validation of MIX: comprehensive free software for meta-analysis of causal research data

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Ikeda Noriaki

2006-10-01

Full Text Available Abstract Background Meta-analysis has become a well-known method for synthesis of quantitative data from previously conducted research in applied health sciences. So far, meta-analysis has been particularly useful in evaluating and comparing therapies and in assessing causes of disease. Consequently, the number of software packages that can perform meta-analysis has increased over the years. Unfortunately, it can take a substantial amount of time to get acquainted with some of these programs and most contain little or no interactive educational material. We set out to create and validate an easy-to-use and comprehensive meta-analysis package that would be simple enough programming-wise to remain available as a free download. We specifically aimed at students and researchers who are new to meta-analysis, with important parts of the development oriented towards creating internal interactive tutoring tools and designing features that would facilitate usage of the software as a companion to existing books on meta-analysis. Results We took an unconventional approach and created a program that uses Excel as a calculation and programming platform. The main programming language was Visual Basic, as implemented in Visual Basic 6 and Visual Basic for Applications in Excel 2000 and higher. The development took approximately two years and resulted in the 'MIX' program, which can be downloaded from the program's website free of charge. Next, we set out to validate the MIX output with two major software packages as reference standards, namely STATA (metan, metabias, and metatrim and Comprehensive Meta-Analysis Version 2. Eight meta-analyses that had been published in major journals were used as data sources. All numerical and graphical results from analyses with MIX were identical to their counterparts in STATA and CMA. The MIX program distinguishes itself from most other programs by the extensive graphical output, the click-and-go (Excel interface, and the

Creativity and Academic Achievement: A Meta-Analysis

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Gajda, Aleksandra; Karwowski, Maciej; Beghetto, Ronald A.

2017-01-01

This article reports on a meta-analysis of 120 studies (total N = 52,578; 782 effects) examining the relationship between creativity and academic achievement in research conducted since the 1960s. Average correlation between creativity and academic achievement was r = 0.22, 95% CI [0.19, 0.24]. An analysis of moderators revealed that this…

Lead and Conduct Problems: A Meta-Analysis

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Marcus, David K.; Fulton, Jessica J.; Clarke, Erin J.

2010-01-01

This meta-analysis examined the association between conduct problems and lead exposure. Nineteen studies on 8,561 children and adolescents were included. The average "r" across all 19 studies was 0.19 (p less than 0.001), which is considered a medium effect size. Studies that assessed lead exposure using hair element analysis yielded…

Use of meta-analysis to combine candidate gene association studies: application to study the relationship between the ESR PvuII polymorphism and sow litter size

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Alfonso Leopoldo

2005-07-01

Full Text Available Abstract This article investigates the application of meta-analysis on livestock candidate gene effects. The PvuII polymorphism of the ESR gene is used as an example. The association among ESR PvuII alleles with the number of piglets born alive and total born in the first (NBA1, TNB1 and later parities (NBA, TNB is reviewed by conducting a meta-analysis of 15 published studies including 9329 sows. Under a fixed effects model, litter size values were significantly lower in the "AA" genotype groups when compared with "AB" and "BB" homozygotes. Under the random effects model, the results were similar although differences between "AA" and "AB" genotype groups were not clearly significant for NBA and TNB. Nevertheless, the most noticeable result was the high and significant heterogeneity estimated among studies. This heterogeneity could be assigned to error sampling, genotype by environment interaction, linkage or epistasis, as referred to in the literature, but also to the hypothesis of population admixture/stratification. It is concluded that meta-analysis can be considered as a helpful analytical tool to synthesise and discuss livestock candidate gene effects. The main difficulty found was the insufficient information on the standard errors of the estimated genotype effects in several publications. Consequently, the convenience of publishing the standard errors or the concrete P-values instead of the test significance level should be recommended to guarantee the quality of candidate gene effect meta-analyses.

Family history of diabetes and the risk of gestational diabetes mellitus in Iran: A systematic review and meta-analysis.

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Moosazadeh, Mahmood; Asemi, Zatollah; Lankarani, Kamran B; Tabrizi, Reza; Maharlouei, Najmeh; Naghibzadeh-Tahami, Ahmad; Yousefzadeh, Gholamreza; Sadeghi, Reza; Khatibi, Seyed Reza; Afshari, Mahdi; Khodadost, Mahmoud; Akbari, Maryam

2017-11-01

Gestational diabetes is the most prevalent metabolic disorder being firstly diagnosed during pregnancy. The relationship between the family history of diabetes and the gestational diabetes mellitus (GDM) has been investigated in several primary studies with a number of contradictions in the results. Hence, the purpose of the present study is to determine the relationship between the GDM and the family history of diabetes using the meta-analysis method. All published papers in main national and international databases were systematically searched with some specific keywords to find the related studies between 2000 and 2016. We calculated the odds ratio (OR) with 95% confidence interval (CI) in analysis for each study using a random-effect and Mantel-Haenzel method. We also determined heterogeneity among these 33 articles and their publication bias. We entered 33 relevant studies of 2516 articles into the meta-analysis process including 2697 women with family history of diabetes mellitus as well as 29134 women without. Of them, 954 and 4372 subjects developed GDM respectively. Combining the results of the primary studies using the meta-analysis method, the overall odds ratio of family history for developing GDM was estimated as of 3.46 (95% CI: 2.80-4.27). This meta-analysis study revealed that the family history of diabetes is an important risk factor for the gestational diabetes mellitus. Copyright © 2016 Diabetes India. Published by Elsevier Ltd. All rights reserved.

Simulation-based power calculations for planning a two-stage individual participant data meta-analysis.

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Ensor, Joie; Burke, Danielle L; Snell, Kym I E; Hemming, Karla; Riley, Richard D

2018-05-18

Researchers and funders should consider the statistical power of planned Individual Participant Data (IPD) meta-analysis projects, as they are often time-consuming and costly. We propose simulation-based power calculations utilising a two-stage framework, and illustrate the approach for a planned IPD meta-analysis of randomised trials with continuous outcomes where the aim is to identify treatment-covariate interactions. The simulation approach has four steps: (i) specify an underlying (data generating) statistical model for trials in the IPD meta-analysis; (ii) use readily available information (e.g. from publications) and prior knowledge (e.g. number of studies promising IPD) to specify model parameter values (e.g. control group mean, intervention effect, treatment-covariate interaction); (iii) simulate an IPD meta-analysis dataset of a particular size from the model, and apply a two-stage IPD meta-analysis to obtain the summary estimate of interest (e.g. interaction effect) and its associated p-value; (iv) repeat the previous step (e.g. thousands of times), then estimate the power to detect a genuine effect by the proportion of summary estimates with a significant p-value. In a planned IPD meta-analysis of lifestyle interventions to reduce weight gain in pregnancy, 14 trials (1183 patients) promised their IPD to examine a treatment-BMI interaction (i.e. whether baseline BMI modifies intervention effect on weight gain). Using our simulation-based approach, a two-stage IPD meta-analysis has meta-analysis was appropriate. Pre-specified adjustment for prognostic factors would increase power further. Incorrect dichotomisation of BMI would reduce power by over 20%, similar to immediately throwing away IPD from ten trials. Simulation-based power calculations could inform the planning and funding of IPD projects, and should be used routinely.

Induced abortion rate in Iran: a meta-analysis.

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Motaghi, Zahra; Poorolajal, Jalal; Keramat, Afsaneh; Shariati, Mohammad; Yunesian, Masud; Masoumi, Seyyedeh Zahra

2013-10-01

About 44 million induced abortions take place worldwide annually, of which 50% are unsafe. The results of studies investigated the induced abortion rate in Iran are inconsistent. The aim of this meta-analysis was to estimate the incidence rate of induced abortion in Iran. National and international electronic databases, as well as conference databases until July 2012 were searched. Reference lists of articles were screened and the studies' authors were contacted for additional unpublished studies. Cross-sectional studies addressing induced abortion in Iran were included in this meta-analysis. The primary outcome of interest was the induced abortion rate (the number of abortions per 1000 women aged 15-44 years in a year) or the ratio (the number of abortions per 100 live births in a year). The secondary outcome of interest was the prevalence of unintended pregnancies (the number of mistimed, unplanned, or unwanted pregnancies per total pregnancies). Data were analyzed using random effect models. Of 603 retrieved studies, using search strategy, 10 studies involving 102,394 participants were eventually included in the meta-analysis. The induced abortion rate and ratio were estimated as 8.9 per 1000 women aged 15-44 years (95% CI: 5.46, 12.33) and 5.34 per 100 live births (95% CI: 3.61, 7.07), respectively. The prevalence of unintended pregnancy was estimated as 27.94 per 100 pregnant women (95% CI: 23.46, 32.42). The results of this meta-analysis helped a better understanding of the incidence of induced abortion in Iran compared to the other developing countries in Asia. However, additional sources of data on abortion other than medical records and survey studies are needed to estimate the true rate of unsafe abortion in Iran.

A Bayesian approach to meta-analysis of plant pathology studies.

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Mila, A L; Ngugi, H K

2011-01-01

Bayesian statistical methods are used for meta-analysis in many disciplines, including medicine, molecular biology, and engineering, but have not yet been applied for quantitative synthesis of plant pathology studies. In this paper, we illustrate the key concepts of Bayesian statistics and outline the differences between Bayesian and classical (frequentist) methods in the way parameters describing population attributes are considered. We then describe a Bayesian approach to meta-analysis and present a plant pathological example based on studies evaluating the efficacy of plant protection products that induce systemic acquired resistance for the management of fire blight of apple. In a simple random-effects model assuming a normal distribution of effect sizes and no prior information (i.e., a noninformative prior), the results of the Bayesian meta-analysis are similar to those obtained with classical methods. Implementing the same model with a Student's t distribution and a noninformative prior for the effect sizes, instead of a normal distribution, yields similar results for all but acibenzolar-S-methyl (Actigard) which was evaluated only in seven studies in this example. Whereas both the classical (P = 0.28) and the Bayesian analysis with a noninformative prior (95% credibility interval [CRI] for the log response ratio: -0.63 to 0.08) indicate a nonsignificant effect for Actigard, specifying a t distribution resulted in a significant, albeit variable, effect for this product (CRI: -0.73 to -0.10). These results confirm the sensitivity of the analytical outcome (i.e., the posterior distribution) to the choice of prior in Bayesian meta-analyses involving a limited number of studies. We review some pertinent literature on more advanced topics, including modeling of among-study heterogeneity, publication bias, analyses involving a limited number of studies, and methods for dealing with missing data, and show how these issues can be approached in a Bayesian framework

A Meta Analysis on Nitrogen Fertilizer Experiments on Cereal Crops in Iran

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alireza koocheki

2017-10-01

Full Text Available Introduction Though chemical fertilizers increase crop production; their overuse has hardened the soil, decreased fertility, strengthened pesticides, polluted air and water, and released greenhouse gases, thereby bringing hazards to human health and environment as well. Using of chemical fertilizer in agriculture has a history of more than fifty years in Iran. Recently, nitrogen fertilizers consume more than 61 percent of the chemical fertilizer in our country. Globally, the role of chemical fertilizers especially nitrogen fertilizers in agricultural production has been widely studied over the past 50 years, and in our country a considerable amount of research in universities has been dedicated to studying in this field. Meta-analysis is a method for analyzing the results of various studies on a subject. In fact, meta-analysis is a type of research on other research to re-examine the various studies carried out on a particular topic, compare them statistically and, using specific statistical techniques, the results of all those studies combine into a single result. Experiments on the effects of nitrogen fertilizers on cereals yield have a long history in Iran. However, because of high variation in the results, a final conclusion is not readily achieved. Materials and methods In this study, the researches of the effect of different levels of nitrogen fertilizers on yield and yield components of cereals (wheat, corn and rice over the past 20 years have been investigated. These studies included a variety of scientific-research articles. So, 46 papers were selected and the information was extracted from them. To overcome such a difficulty meta-analysis was used to combine and re-analyze the data of independent experiments. For this, 46 published papers related to nitrogen application on cereals including 23, 14 and 9 papers, respectively on wheat, corn and rice were selected based on criteria to satisfy the required data for meta-analysis

A Meta-Analysis of Cross Sectional Studies Investigating Language in Maltreated Children

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Lum, Jarrad A. G.; Powell, Martine; Timms, Lydia; Snow, Pamela

2015-01-01

Purpose: In this review article, meta-analysis was used to summarize research investigating language skills in maltreated children. Method: A systematic search of published studies was undertaken. Studies were included in the meta-analysis if they investigated language skills in groups comprising maltreated and nonmaltreated children. Studies were…

Managing complex research datasets using electronic tools: A meta-analysis exemplar

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Brown, Sharon A.; Martin, Ellen E.; Garcia, Theresa J.; Winter, Mary A.; García, Alexandra A.; Brown, Adama; Cuevas, Heather E.; Sumlin, Lisa L.

2013-01-01

Meta-analyses of broad scope and complexity require investigators to organize many study documents and manage communication among several research staff. Commercially available electronic tools, e.g., EndNote, Adobe Acrobat Pro, Blackboard, Excel, and IBM SPSS Statistics (SPSS), are useful for organizing and tracking the meta-analytic process, as well as enhancing communication among research team members. The purpose of this paper is to describe the electronic processes we designed, using commercially available software, for an extensive quantitative model-testing meta-analysis we are conducting. Specific electronic tools improved the efficiency of (a) locating and screening studies, (b) screening and organizing studies and other project documents, (c) extracting data from primary studies, (d) checking data accuracy and analyses, and (e) communication among team members. The major limitation in designing and implementing a fully electronic system for meta-analysis was the requisite upfront time to: decide on which electronic tools to use, determine how these tools would be employed, develop clear guidelines for their use, and train members of the research team. The electronic process described here has been useful in streamlining the process of conducting this complex meta-analysis and enhancing communication and sharing documents among research team members. PMID:23681256

Granisetron plus dexamethasone for prevention of postoperative nausea and vomiting in patients undergoing laparoscopic surgery: A meta-analysis

OpenAIRE

Zhu, Min; Zhou, Chengmao; Huang, Bing; Ruan, Lin; Liang, Rui

2017-01-01

Objective This study was designed to compare the effectiveness of granisetron plus dexamethasone for preventing postoperative nausea and vomiting (PONV) in patients undergoing laparoscopic surgery. Methods We searched the literature in the Cochrane Library, PubMed, EMBASE, and CNKI. Results In total, 11 randomized controlled trials were enrolled in this analysis. The meta-analysis showed that granisetron in combination with dexamethasone was significantly more effective than granisetron alone...

An improved method for bivariate meta-analysis when within-study correlations are unknown.

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Hong, Chuan; D Riley, Richard; Chen, Yong

2018-03-01

Multivariate meta-analysis, which jointly analyzes multiple and possibly correlated outcomes in a single analysis, is becoming increasingly popular in recent years. An attractive feature of the multivariate meta-analysis is its ability to account for the dependence between multiple estimates from the same study. However, standard inference procedures for multivariate meta-analysis require the knowledge of within-study correlations, which are usually unavailable. This limits standard inference approaches in practice. Riley et al proposed a working model and an overall synthesis correlation parameter to account for the marginal correlation between outcomes, where the only data needed are those required for a separate univariate random-effects meta-analysis. As within-study correlations are not required, the Riley method is applicable to a wide variety of evidence synthesis situations. However, the standard variance estimator of the Riley method is not entirely correct under many important settings. As a consequence, the coverage of a function of pooled estimates may not reach the nominal level even when the number of studies in the multivariate meta-analysis is large. In this paper, we improve the Riley method by proposing a robust variance estimator, which is asymptotically correct even when the model is misspecified (ie, when the likelihood function is incorrect). Simulation studies of a bivariate meta-analysis, in a variety of settings, show a function of pooled estimates has improved performance when using the proposed robust variance estimator. In terms of individual pooled estimates themselves, the standard variance estimator and robust variance estimator give similar results to the original method, with appropriate coverage. The proposed robust variance estimator performs well when the number of studies is relatively large. Therefore, we recommend the use of the robust method for meta-analyses with a relatively large number of studies (eg, m≥50). When the

A Bayesian Nonparametric Meta-Analysis Model

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Karabatsos, George; Talbott, Elizabeth; Walker, Stephen G.

2015-01-01

In a meta-analysis, it is important to specify a model that adequately describes the effect-size distribution of the underlying population of studies. The conventional normal fixed-effect and normal random-effects models assume a normal effect-size population distribution, conditionally on parameters and covariates. For estimating the mean overall…

Dyadic Interracial Interactions: A Meta-Analysis

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Toosi, Negin R.; Babbitt, Laura G.; Ambady, Nalini; Sommers, Samuel R.

2012-01-01

This meta-analysis examined over 40 years of research on interracial interactions by exploring 4 types of outcomes: explicit attitudes toward interaction partners, participants' self-reports of their own emotional state, nonverbal or observed behavior, and objective measures of performance. Data were collected from 108 samples (N = 12,463)…

Vision and Relevant Risk Factor Interventions for Preventing Falls among Older People: A Network Meta-analysis.

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Zhang, Xin-Yi; Shuai, Jian; Li, Li-Ping

2015-05-28

Our study objective was to determine the effect of vision intervention and combinations of different intervention components on preventing falls and fall-related injuries among older people. Six electronic databases were searched to identify seven articles published before May, 2014. We conducted a systematic review of data from seven randomized controlled trails and identified eight regimens: vision intervention alone (V), vision plus exercise (referred to as physical exercise) interventions (V + E), vision plus home hazard interventions (V + HH), vision plus exercise plus home hazard interventions (V + E + HH), vision plus exercise plus sensation interventions (V + E + S), vision plus hearing interventions (V + H), vision plus various risk factor assessment and interventions (V + VRF), and the control group (C, no intervention group). The main outcome was the incidence of falls during the follow-up period. Seven papers included 2723 participants. Network meta-analysis of seven trials, using pairwise comparisons between each intervention, indicated there was no significant difference. However, there was a trend in which intervention incorporating V + VRF had more advantages than any other combination of interventions. In conclusion, V + VRF proves to be more effective than other V combination interventions in preventing falls in older people (≥65 years of age). V alone appears less effective in our network meta-analysis.

Comparison of Maladaptive Meta Cognition Beliefs among Substance Dependents and Non-Dependents

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Omid Saed

2011-05-01

Full Text Available Introduction: The aim of present research was the comparison of maladaptive meta cognition beliefs among substance abusers and non abusers. Methods: For this purpose 70 substance abusers and 70 individuals from the general population by purposive sampling participated in this research and responded to meta cognition questionnaire. For analysis data multiple analysis of variance (MANOVA and discriminant analysis were run. Results: MANOVA revealed that there was significant difference in linier combination of dependent variables (meta cognitive beliefs among two groups also, analysis of dependent variables lonely showed that two groups were significantly different in Positive meta cognitive beliefs, "Negative meta cognitive beliefs", "lack of cognitive confidence", "need to control of thoughts", and "cognitive self-consciousness". Also, the discriminant analysis indicated that three meta-cognitive factors included “negative meta cognitive beliefs", "need to control of thoughts" and "cognitive self-consciousness" were significant predictors to discriminate substance abusers. Conclusion: With consideration of the results it can be concluded that substance abusers have more maladaptive beliefs and these maladaptive beliefs can lead to susceptibility toward substance abuse and staying in this disorder. It is hoped that psychotherapists can be more useful in treating and staying in this research.

Meta-analysis: banding ligation and medical interventions for the prevention of rebleeding from oesophageal varices

DEFF Research Database (Denmark)

Thiele, Maja; Krag, A; Rohde, Ulrich

2012-01-01

In patients with oesophageal varices, the combination of endoscopic variceal ligation (EVL) and medical therapy is recommended as standard of care for prevention of rebleeding. The results of previous meta-analyses on this topic are equivocal.......In patients with oesophageal varices, the combination of endoscopic variceal ligation (EVL) and medical therapy is recommended as standard of care for prevention of rebleeding. The results of previous meta-analyses on this topic are equivocal....

Thyroid Cytology in India: Contemporary Review and Meta-analysis.

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Agarwal, Shipra; Jain, Deepali

2017-11-01

Fine-needle aspiration cytology (FNAC) is a screening test for triaging thyroid nodules, aiding in subsequent clinical management. However, the advantages have been overshadowed by the multiplicity of reporting systems and a wide range of nomenclature used. The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) was formulated in 2007, to give the world a uniform thyroid cytology reporting system, facilitating easy interpretation by the clinicians. Here, we review the status of thyroid FNAC in India in terms of various reporting systems used including a meta-analysis of the previously published data. An extensive literature search was performed using internet search engines. The reports with detailed classification system used in thyroid cytology were included. The meta-analysis of published data was compared with the implied risk of malignancy by TBSRTC. More than 50 studies were retrieved and evaluated. TBSRTC is currently the most widely used reporting system with different studies showing good efficacy and interobserver concordance. Ancillary techniques have, as of now, limited applicability and acceptability in thyroid cytology in India. Twenty-eight published articles met the criteria for inclusion in the meta-analysis. When compared with TBSRTC recommendations, the meta-analysis showed a higher risk of malignancy for categories I and III. Thyroid FNAC is practiced all over India. TBSRTC has found widespread acceptance, with most institutions using this system for routine thyroid cytology reporting. However, reasons for a high malignancy risk for categories I and III need to be looked into. Various possible contributing factors are discussed in the review.

Methicillin resistant Staphylococcus aureus in Ethiopia: a meta-analysis.

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Eshetie, Setegn; Tarekegn, Fentahun; Moges, Feleke; Amsalu, Anteneh; Birhan, Wubet; Huruy, Kahsay

2016-11-21

The burden of methicillin resistant Staphylococcus aureus is a major public health concern worldwide; however the overall epidemiology of multidrug resistant strains is neither coordinated nor harmonized, particularly in developing countries including Ethiopia. Therefore, the aim of this meta-analysis was to assess the burden of methicillin resistant Staphylococcos aureus and its antibiotic resistance pattern in Ethiopia at large. PubMed, Google Scholar, and lancet databases were searched and a total of 20 studies have been selected for meta-analysis. Six authors have independently extracts data on the prevalence of methicillin resistant Staphylococcus aureus among clinical isolates of Staphylococcus aureus. Statistical analysis was achieved by using Open meta-analyst (version 3.13) and Comprehensive meta-analysis (version 3.3) softwares. The overall prevalence of methicillin resistant Staphylococcus aureus and its antibiotic resistance pattern were pooled by using the forest plot, table and figure with 95% CI. The pooled prevalence of methicillin resistant Staphylococcus aureus was 32.5% (95% CI, 24.1 to 40.9%). Moreover, methicillin resistant Staphylococcus aureus strains were found to be highly resistant to penicillin, ampicillin, erythromycin, and amoxicillin, with a pooled resistance ratio of 99.1, 98.1, 97.2 and 97.1%, respectively. On the other hand, comparably low levels of resistance ratio were noted to vancomycin, 5.3%. The overall burden of methicillin resistant Staphylococcus aureus is considerably high, besides these strains showed extreme resistance to penicillin, ampicillin, erythromycin and amoxicillin. In principle, appropriate use of antibiotics, applying safety precautions are the key to reduce the spread of multidrug resistant strains, methicillin resistant Staphylococcus aureus in particular.

The paradox of intragroup conflict: a meta-analysis.

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de Wit, Frank R C; Greer, Lindred L; Jehn, Karen A

2012-03-01

Since the meta-analysis by De Dreu and Weingart (2003b) on the effects of intragroup conflict on group outcomes, more than 80 new empirical studies of conflict have been conducted, often investigating more complex, moderated relationships between conflict and group outcomes, as well as new types of intragroup conflict, such as process conflict. To explore the trends in this new body of literature, we conducted a meta-analysis of 116 empirical studies of intragroup conflict (n = 8,880 groups) and its relationship with group outcomes. To address the heterogeneity across the studies included in the meta-analysis, we also investigated a number of moderating variables. Stable negative relationships were found between relationship and process conflict and group outcomes. In contrast to the results of De Dreu and Weingart, we did not find a strong and negative association between task conflict and group performance. Analyses of main effects as well as moderator analyses revealed a more complex picture. Task conflict and group performance were more positively related among studies where the association between task and relationship conflict was relatively weak, in studies conducted among top management teams rather than non-top management teams, and in studies where performance was measured in terms of financial performance or decision quality rather than overall performance.

Dietary patterns and depression risk: A meta-analysis.

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Li, Ye; Lv, Mei-Rong; Wei, Yan-Jin; Sun, Ling; Zhang, Ji-Xiang; Zhang, Huai-Guo; Li, Bin

2017-07-01

Although some studies have reported potential associations of dietary patterns with depression risk, a consistent perspective hasn't been estimated to date. Therefore, we conducted this meta-analysis to evaluate the relation between dietary patterns and the risk of depression. A literature research was conducted searching MEDLINE and EMBASE databases up to September 2016. In total, 21 studies from ten countries met the inclusion criteria and were included in the present meta-analysis. A dietary pattern characterized by a high intakes of fruit, vegetables, whole grain, fish, olive oil, low-fat dairy and antioxidants and low intakes of animal foods was apparently associated with a decreased risk of depression. A dietary pattern characterized by a high consumption of red and/or processed meat, refined grains, sweets, high-fat dairy products, butter, potatoes and high-fat gravy, and low intakes of fruits and vegetables is associated with an increased risk of depression. The results of this meta-analysis suggest that healthy pattern may decrease the risk of depression, whereas western-style may increase the risk of depression. However, more randomized controlled trails and cohort studies are urgently required to confirm this findings. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Meta-analysis of Cancer Gene Profiling Data.

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Roy, Janine; Winter, Christof; Schroeder, Michael

2016-01-01

The simultaneous measurement of thousands of genes gives the opportunity to personalize and improve cancer therapy. In addition, the integration of meta-data such as protein-protein interaction (PPI) information into the analyses helps in the identification and prioritization of genes from these screens. Here, we describe a computational approach that identifies genes prognostic for outcome by combining gene profiling data from any source with a network of known relationships between genes.

Grey literature in meta-analyses.

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Conn, Vicki S; Valentine, Jeffrey C; Cooper, Harris M; Rantz, Marilyn J

2003-01-01

In meta-analysis, researchers combine the results of individual studies to arrive at cumulative conclusions. Meta-analysts sometimes include "grey literature" in their evidential base, which includes unpublished studies and studies published outside widely available journals. Because grey literature is a source of data that might not employ peer review, critics have questioned the validity of its data and the results of meta-analyses that include it. To examine evidence regarding whether grey literature should be included in meta-analyses and strategies to manage grey literature in quantitative synthesis. This article reviews evidence on whether the results of studies published in peer-reviewed journals are representative of results from broader samplings of research on a topic as a rationale for inclusion of grey literature. Strategies to enhance access to grey literature are addressed. The most consistent and robust difference between published and grey literature is that published research is more likely to contain results that are statistically significant. Effect size estimates of published research are about one-third larger than those of unpublished studies. Unfunded and small sample studies are less likely to be published. Yet, importantly, methodological rigor does not differ between published and grey literature. Meta-analyses that exclude grey literature likely (a) over-represent studies with statistically significant findings, (b) inflate effect size estimates, and (c) provide less precise effect size estimates than meta-analyses including grey literature. Meta-analyses should include grey literature to fully reflect the existing evidential base and should assess the impact of methodological variations through moderator analysis.

The countermovement jump to monitor neuromuscular status: A meta-analysis.

Science.gov (United States)

Claudino, João Gustavo; Cronin, John; Mezêncio, Bruno; McMaster, Daniel Travis; McGuigan, Michael; Tricoli, Valmor; Amadio, Alberto Carlos; Serrão, Julio Cerca

2017-04-01

The primary objective of this meta-analysis was to compare countermovement jump (CMJ) performance in studies that reported the highest value as opposed to average value for the purposes of monitoring neuromuscular status (i.e., fatigue and supercompensation). The secondary aim was to determine the sensitivity of the dependent variables. Systematic review with meta-analysis. The meta-analysis was conducted on the highest or average of a number of CMJ variables. Multiple literature searches were undertaken in Pubmed, Scopus, and Web of Science to identify articles utilizing CMJ to monitor training status. Effect sizes (ES) with 95% confidence interval (95% CI) were calculated using the mean and standard deviation of the pre- and post-testing data. The coefficient of variation (CV) with 95% CI was also calculated to assess the level of instability of each variable. Heterogeneity was assessed using a random-effects model. 151 articles were included providing a total of 531 ESs for the meta-analyses; 85.4% of articles used highest CMJ height, 13.2% used average and 1.3% used both when reporting changes in CMJ performance. Based on the meta-analysis, average CMJ height was more sensitive than highest CMJ height in detecting CMJ fatigue and supercompensation. Furthermore, other CMJ variables such as peak power, mean power, peak velocity, peak force, mean impulse, and power were sensitive in tracking the supercompensation effects of training. The average CMJ height was more sensitive than highest CMJ height in monitoring neuromuscular status; however, further investigation is needed to determine the sensitivity of other CMJ performance variables. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Association of vitamin C with the risk of age-related cataract: a meta-analysis.

Science.gov (United States)

Wei, Lin; Liang, Ge; Cai, Chunmei; Lv, Jin