A secondary meta-synthesis of qualitative studies of gender and access to cardiac rehabilitation.

PubMed

Angus, Jan E; King-Shier, Kathryn M; Spaling, Melisa A; Duncan, Amanda S; Jaglal, Susan B; Stone, James A; Clark, Alexander M

2015-08-01

To discuss issues in the theorization and study of gender observed during a qualitative meta-synthesis of influences on uptake of secondary prevention and cardiac rehabilitation services. Women and men can equally benefit from secondary prevention/cardiac rehabilitation and there is a need to understand gender barriers to uptake. Meta-method analysis secondary to meta-synthesis. For the meta-synthesis, a systematic search was performed to identify and retrieve studies published as full papers during or after 1995 and contained: a qualitative research component wholly or in a mixed method design, extractable population specific data or themes for referral to secondary prevention programmes and adults ≥18 years. Databases searched between January 1995-31 October 2011 included: CSA Sociological Abstracts, EBSCOhost CINAHL, EBSCOhost Gender Studies, EBSCOhost Health Source Nursing: Academic Edition, EBSCOhost SPORTDiscus, EBSCOhost SocINDEX. Studies were reviewed against inclusion/exclusion criteria. Included studies were subject to quality appraisal and standardized data extraction. Of 2264 screened articles, 69 were included in the meta-method analysis. Only four studies defined gender or used gender theories. Findings were mostly presented as inherently the characteristic of gendered worldviews of participants. The major themes suggest a mismatch between secondary prevention/cardiac rehabilitation services and consumers' needs, which are usually portrayed as differing according to gender but may also be subject to intersecting influences such as age or socioeconomic status. There is a persistent lack of theoretically informed gender analysis in qualitative literature in this field. Theory-driven gender analysis will improve the conceptual clarity of the evidence base for gender-sensitive cardiac rehabilitation programme development. © 2015 John Wiley & Sons Ltd.

Conducting a meta-ethnography of qualitative literature: Lessons learnt

PubMed Central

Atkins, Salla; Lewin, Simon; Smith, Helen; Engel, Mark; Fretheim, Atle; Volmink, Jimmy

2008-01-01

Background Qualitative synthesis has become more commonplace in recent years. Meta-ethnography is one of several methods for synthesising qualitative research and is being used increasingly within health care research. However, many aspects of the steps in the process remain ill-defined. Discussion We utilized the seven stages of the synthesis process to synthesise qualitative research on adherence to tuberculosis treatment. In this paper we discuss the methodological and practical challenges faced; of particular note are the methods used in our synthesis, the additional steps that we found useful in clarifying the process, and the key methodological challenges encountered in implementing the meta-ethnographic approach. The challenges included shaping an appropriate question for the synthesis; identifying relevant studies; assessing the quality of the studies; and synthesising findings across a very large number of primary studies from different contexts and research traditions. We offer suggestions that may assist in undertaking meta-ethnographies in the future. Summary Meta-ethnography is a useful method for synthesising qualitative research and for developing models that interpret findings across multiple studies. Despite its growing use in health research, further research is needed to address the wide range of methodological and epistemological questions raised by the approach. PMID:18416812

A qualitative meta-synthesis and theory of postpartum depression.

PubMed

Mollard, Elizabeth K

2014-09-01

To synthesize existing qualitative literature on the first-hand experiences of women suffering from postpartum depression (PPD), to uncover potential common themes, a meta-synthesis of 12 qualitative studies using Noblit and Hare's 7-phase model of meta-ethnography was used. Four themes were discovered: crushed maternal role expectation, going into hiding, loss of sense of self, intense feelings of vulnerability, plus practical life concerns. A preliminary theory of PPD as a 4-step process is proposed, based on the relationships between the themes in this meta-synthesis. This 4-step process is compared and contrasted with Cheryl Tatano Beck's 4-stage theory of PPD "Teetering on the Edge". This meta-synthesis and theory offers a significant contribution to the literature in helping identify PPD distinctly from depression outside of the postpartum period, and deserves further study.

Meta-analysis, complexity, and heterogeneity: a qualitative interview study of researchers' methodological values and practices.

PubMed

Lorenc, Theo; Felix, Lambert; Petticrew, Mark; Melendez-Torres, G J; Thomas, James; Thomas, Sian; O'Mara-Eves, Alison; Richardson, Michelle

2016-11-16

Complex or heterogeneous data pose challenges for systematic review and meta-analysis. In recent years, a number of new methods have been developed to meet these challenges. This qualitative interview study aimed to understand researchers' understanding of complexity and heterogeneity and the factors which may influence the choices researchers make in synthesising complex data. We conducted interviews with a purposive sample of researchers (N = 19) working in systematic review or meta-analysis across a range of disciplines. We analysed data thematically using a framework approach. Participants reported using a broader range of methods and data types in complex reviews than in traditional reviews. A range of techniques are used to explore heterogeneity, but there is some debate about their validity, particularly when applied post hoc. Technical considerations of how to synthesise complex evidence cannot be isolated from questions of the goals and contexts of research. However, decisions about how to analyse data appear to be made in a largely informal way, drawing on tacit expertise, and their relation to these broader questions remains unclear.

A meta-summary of qualitative findings on the lived experience among culturally diverse domestic violence survivors.

PubMed

Childress, Saltanat

2013-09-01

This meta-summary study explores, extracts, and summarizes themes from related qualitative studies on the lived experiences and coping mechanisms among culturally diverse domestic violence survivors. Using Sandelowski and Barroso's meta-summary strategy, a systematic literature review of articles published between 1990 and 2010 was conducted using a qualitative approach. Of a total of 802 studies, nine met the study inclusion criteria. This meta-summary of nine studies confirms the recurring themes in primary qualitative studies in the literature that illustrate women's experiences of domestic violence. These themes include (a) the effects of violence, (b) the cyclical nature of violence, (c) normalizing and tolerating violence, (d) the strength and resilience of victims, (e) barriers to help-seeking, and (f) the role of substance use in domestic violence. The review shows key cross-cultural differences in women's perceptions of abuse and the causes and strategies for responding to abuse. The review also reveals the lack of studies on domestic violence among women from Central Asia and the former Soviet Union.

Parental experiences of providing skin-to-skin care to their newborn infant--part 2: a qualitative meta-synthesis.

PubMed

Anderzén-Carlsson, Agneta; Lamy, Zeni C; Tingvall, Maria; Eriksson, Mats

2014-01-01

To synthesize and interpret qualitative research findings focusing on parental experiences of skin-to-skin care (SSC) for newborn infants. SSC induces many benefits for newborn infants and their parents. Three meta-analyses have been conducted on physiological outcomes, but no previous qualitative meta-synthesis on parental experiences of SSC has been identified. The present meta-synthesis was guided by the methodology described by Paterson and co-workers. Four databases were searched, without year or language limitations, up until December 2013. Manual searches were also performed. The searches and subsequent quality appraisal resulted in the inclusion of 29 original qualitative papers from 9 countries, reporting experiences from 401 mothers and 94 fathers. The meta-synthesis entails a meta-data analysis, analysis of meta-method, and meta-theory in the included primary studies. Based on the three analyses, the meta-synthesis represents a new interpretation of a phenomenon. The results of the meta-data analysis have been presented as a qualitative systematic review in a separate paper. When synthesizing and interpreting the findings from the included analyses, a theoretical model of Becoming a parent under unfamiliar circumstances emerged. Providing SSC seems to be a restorative as well as an energy-draining experience. A supportive environment has been described as facilitating the restorative experience, whereas obstacles in the environment seem to make the provision of SSC energy-draining for parents. When the process is experienced as positive, it facilitates the growth of parental self-esteem and makes the parents ready to assume full responsibility for their child. The results show that SSC can be interpreted not only as a family-including and important health care intervention but also in terms of actually becoming a parent. The process of becoming a parent in this specific situation is influenced by external factors in three different levels; family and

Why, when and how to update a meta-ethnography qualitative synthesis.

PubMed

France, Emma F; Wells, Mary; Lang, Heidi; Williams, Brian

2016-03-15

Meta-ethnography is a unique, systematic, qualitative synthesis approach widely used to provide robust evidence on patient and clinician beliefs and experiences and understandings of complex social phenomena. It can make important theoretical and conceptual contributions to health care policy and practice. Since beliefs, experiences, health care contexts and social phenomena change over time, the continued relevance of the findings from meta-ethnographies cannot be assumed. However, there is little guidance on whether, when and how meta-ethnographies should be updated; Cochrane guidance on updating reviews of intervention effectiveness is unlikely to be fully appropriate. This is the first in-depth discussion on updating a meta-ethnography; it explores why, when and how to update a meta-ethnography. Three main methods of updating the analysis and synthesis are examined. Advantages and disadvantages of each method are outlined, relating to the context, purpose, process and output of the update and the nature of the new data available. Recommendations are made for the appropriate use of each method, and a worked example of updating a meta-ethnography is provided. This article makes a unique contribution to this evolving area of meta-ethnography methodology.

Deriving percentage study weights in multi-parameter meta-analysis models: with application to meta-regression, network meta-analysis and one-stage individual participant data models.

PubMed

Riley, Richard D; Ensor, Joie; Jackson, Dan; Burke, Danielle L

2017-01-01

Many meta-analysis models contain multiple parameters, for example due to multiple outcomes, multiple treatments or multiple regression coefficients. In particular, meta-regression models may contain multiple study-level covariates, and one-stage individual participant data meta-analysis models may contain multiple patient-level covariates and interactions. Here, we propose how to derive percentage study weights for such situations, in order to reveal the (otherwise hidden) contribution of each study toward the parameter estimates of interest. We assume that studies are independent, and utilise a decomposition of Fisher's information matrix to decompose the total variance matrix of parameter estimates into study-specific contributions, from which percentage weights are derived. This approach generalises how percentage weights are calculated in a traditional, single parameter meta-analysis model. Application is made to one- and two-stage individual participant data meta-analyses, meta-regression and network (multivariate) meta-analysis of multiple treatments. These reveal percentage study weights toward clinically important estimates, such as summary treatment effects and treatment-covariate interactions, and are especially useful when some studies are potential outliers or at high risk of bias. We also derive percentage study weights toward methodologically interesting measures, such as the magnitude of ecological bias (difference between within-study and across-study associations) and the amount of inconsistency (difference between direct and indirect evidence in a network meta-analysis).

Parental experiences of providing skin-to-skin care to their newborn infant—Part 2: A qualitative meta-synthesis

PubMed Central

Anderzén-Carlsson, Agneta; Lamy, Zeni C.; Tingvall, Maria; Eriksson, Mats

2014-01-01

Aim To synthesize and interpret qualitative research findings focusing on parental experiences of skin-to-skin care (SSC) for newborn infants. Background SSC induces many benefits for newborn infants and their parents. Three meta-analyses have been conducted on physiological outcomes, but no previous qualitative meta-synthesis on parental experiences of SSC has been identified. Design The present meta-synthesis was guided by the methodology described by Paterson and co-workers. Data sources Four databases were searched, without year or language limitations, up until December 2013. Manual searches were also performed. The searches and subsequent quality appraisal resulted in the inclusion of 29 original qualitative papers from 9 countries, reporting experiences from 401 mothers and 94 fathers. Review methods The meta-synthesis entails a meta-data analysis, analysis of meta-method, and meta-theory in the included primary studies. Based on the three analyses, the meta-synthesis represents a new interpretation of a phenomenon. The results of the meta-data analysis have been presented as a qualitative systematic review in a separate paper. Results When synthesizing and interpreting the findings from the included analyses, a theoretical model of Becoming a parent under unfamiliar circumstances emerged. Providing SSC seems to be a restorative as well as an energy-draining experience. A supportive environment has been described as facilitating the restorative experience, whereas obstacles in the environment seem to make the provision of SSC energy-draining for parents. When the process is experienced as positive, it facilitates the growth of parental self-esteem and makes the parents ready to assume full responsibility for their child. Conclusion The results show that SSC can be interpreted not only as a family-including and important health care intervention but also in terms of actually becoming a parent. The process of becoming a parent in this specific situation is

Meta-GWAS and Meta-Analysis of Exome Array Studies Do Not Reveal Genetic Determinants of Serum Hepcidin

PubMed Central

Galesloot, Tessel E.; van Dijk, Freerk; Geurts-Moespot, Anneke J.; Girelli, Domenico; Kiemeney, Lambertus A. L. M.; Sweep, Fred C. G. J.; Swertz, Morris A.; van der Meer, Peter; Camaschella, Clara; Toniolo, Daniela; Vermeulen, Sita H.; van der Harst, Pim; Swinkels, Dorine W.

2016-01-01

Serum hepcidin concentration is regulated by iron status, inflammation, erythropoiesis and numerous other factors, but underlying processes are incompletely understood. We studied the association of common and rare single nucleotide variants (SNVs) with serum hepcidin in one Italian study and two large Dutch population-based studies. We genotyped common SNVs with genome-wide association study (GWAS) arrays and subsequently performed imputation using the 1000 Genomes reference panel. Cohort-specific GWAS were performed for log-transformed serum hepcidin, adjusted for age and gender, and results were combined in a fixed-effects meta-analysis (total N 6,096). Six top SNVs (p<5x10-6) were genotyped in 3,821 additional samples, but associations were not replicated. Furthermore, we meta-analyzed cohort-specific exome array association results of rare SNVs with serum hepcidin that were available for two of the three cohorts (total N 3,226), but no exome-wide significant signal (p<1.4x10-6) was identified. Gene-based meta-analyses revealed 19 genes that showed significant association with hepcidin. Our results suggest the absence of common SNVs and rare exonic SNVs explaining a large proportion of phenotypic variation in serum hepcidin. We recommend extension of our study once additional substantial cohorts with hepcidin measurements, GWAS and/or exome array data become available in order to increase power to identify variants that explain a smaller proportion of hepcidin variation. In addition, we encourage follow-up of the potentially interesting genes that resulted from the gene-based analysis of low-frequency and rare variants. PMID:27846281

A meta-ethnography of interview-based qualitative research studies on medical students' views and experiences of empathy.

PubMed

Jeffrey, David

2016-12-01

Quantitative research suggests that medical students' empathy declines during their training. This meta-ethnography asks: What new understanding may be gained by a synthesis of interview-based qualitative research on medical students' views and experiences of empathy? How can such a synthesis be undertaken? A meta-ethnography synthesizes individual qualitative studies to generate knowledge increasing understanding and informing debate. A literature search yielded eight qualitative studies which met the inclusion criteria. These were analyzed from a phenomenological and interpretative perspective. The meta-ethnography revealed a conceptual confusion around empathy and a tension in medical education between distancing and connecting with patients. Barriers to empathy included a lack of patient contact and a strong emphasis on the biomedical over the psycho-social aspects of the curriculum. A number of influences discussed in the paper lead students to adopt less overt ways of showing their empathy. These insights deepen our understanding of the apparent decline in empathy in medical students. The lessons from these studies suggest that future curriculum development should include earlier patient contact, more emphasis on psycho-social aspects of care and address the barriers to empathy to ensure that tomorrow's doctors are empathetic as well as competent.

Synthesizing evidence on complex interventions: how meta-analytical, qualitative, and mixed-method approaches can contribute.

PubMed

Petticrew, Mark; Rehfuess, Eva; Noyes, Jane; Higgins, Julian P T; Mayhew, Alain; Pantoja, Tomas; Shemilt, Ian; Sowden, Amanda

2013-11-01

Although there is increasing interest in the evaluation of complex interventions, there is little guidance on how evidence from complex interventions may be reviewed and synthesized, and the relevance of the plethora of evidence synthesis methods to complexity is unclear. This article aims to explore how different meta-analytical approaches can be used to examine aspects of complexity; describe the contribution of various narrative, tabular, and graphical approaches to synthesis; and give an overview of the potential choice of selected qualitative and mixed-method evidence synthesis approaches. The methodological discussions presented here build on a 2-day workshop held in Montebello, Canada, in January 2012, involving methodological experts from the Campbell and Cochrane Collaborations and from other international review centers (Anderson L, Petticrew M, Chandler J, et al. systematic reviews of complex interventions. In press). These systematic review methodologists discussed the broad range of existing methods and considered the relevance of these methods to reviews of complex interventions. The evidence from primary studies of complex interventions may be qualitative or quantitative. There is a wide range of methodological options for reviewing and presenting this evidence. Specific contributions of statistical approaches include the use of meta-analysis, meta-regression, and Bayesian methods, whereas narrative summary approaches provide valuable precursors or alternatives to these. Qualitative and mixed-method approaches include thematic synthesis, framework synthesis, and realist synthesis. A suitable combination of these approaches allows synthesis of evidence for understanding complex interventions. Reviewers need to consider which aspects of complex interventions should be a focus of their review and what types of quantitative and/or qualitative studies they will be including, and this will inform their choice of review methods. These may range from

Teaching meta-analysis using MetaLight.

PubMed

Thomas, James; Graziosi, Sergio; Higgins, Steve; Coe, Robert; Torgerson, Carole; Newman, Mark

2012-10-18

Meta-analysis is a statistical method for combining the results of primary studies. It is often used in systematic reviews and is increasingly a method and topic that appears in student dissertations. MetaLight is a freely available software application that runs simple meta-analyses and contains specific functionality to facilitate the teaching and learning of meta-analysis. While there are many courses and resources for meta-analysis available and numerous software applications to run meta-analyses, there are few pieces of software which are aimed specifically at helping those teaching and learning meta-analysis. Valuable teaching time can be spent learning the mechanics of a new software application, rather than on the principles and practices of meta-analysis. We discuss ways in which the MetaLight tool can be used to present some of the main issues involved in undertaking and interpreting a meta-analysis. While there are many software tools available for conducting meta-analysis, in the context of a teaching programme such software can require expenditure both in terms of money and in terms of the time it takes to learn how to use it. MetaLight was developed specifically as a tool to facilitate the teaching and learning of meta-analysis and we have presented here some of the ways it might be used in a training situation.

Is Disgust Proneness Associated With Anxiety and Related Disorders? A Qualitative Review and Meta-Analysis of Group Comparison and Correlational Studies.

PubMed

Olatunji, Bunmi O; Armstrong, Thomas; Elwood, Lisa

2017-07-01

Research suggests that disgust may be linked to the etiology of some anxiety-related disorders. The present investigation reviews this literature and employs separate meta-analyses of clinical group comparison and correlational studies to examine the association between disgust proneness and anxiety-related disorder symptoms. Meta-analysis of 43 group comparison studies revealed those high in anxiety disorder symptoms reported significantly more disgust proneness than those low in anxiety symptoms. Although this effect was not moderated by clinical versus analogue studies or type of disorder, larger group differences were observed for those high in anxiety symptoms associated with contagion concerns compared to those high in anxiety symptoms not associated with contagion concerns. Similarly, meta-analysis of correlational data across 83 samples revealed moderate associations between disgust proneness and anxiety-related disorder symptoms. Moderator analysis revealed that the association between disgust proneness and anxiety-related disorder symptoms was especially robust for anxiety symptoms associated with contagion concerns. After controlling for measures of negative affect, disgust proneness continued to be moderately correlated with anxiety-related disorder symptoms. However, negative affect was no longer significantly associated with symptoms of anxiety-related disorders when controlling for disgust proneness. The implications of these findings are discussed in the context of a novel transdiagnostic model.

Meta-Study as Diagnostic: Toward Content Over Form in Qualitative Synthesis.

PubMed

Frost, Julia; Garside, Ruth; Cooper, Chris; Britten, Nicky

2016-02-01

Having previously conducted qualitative syntheses of the diabetes literature, we wanted to explore the changes in theoretical approaches, methodological practices, and the construction of substantive knowledge which have recently been presented in the qualitative diabetes literature. The aim of this research was to explore the feasibility of synthesizing existing qualitative syntheses of patient perspectives of diabetes using meta-study methodology. A systematic review of qualitative literature, published between 2000 and 2013, was conducted. Six articles were identified as qualitative syntheses. The meta-study methodology was used to compare the theoretical, methodological, analytic, and synthetic processes across the six studies, exploring the potential for an overarching synthesis. We identified that while research questions have increasingly concentrated on specific aspects of diabetes, the focus on systematic review processes has led to the neglect of qualitative theory and methods. This can inhibit the production of compelling results with meaningful clinical applications. Although unable to produce a synthesis of syntheses, we recommend that researchers who conduct qualitative syntheses pay equal attention to qualitative traditions and systematic review processes, to produce research products that are both credible and applicable. © The Author(s) 2015.

The Student Affair Organizational Dissertation: A Bounded Qualitative Meta-Study

ERIC Educational Resources Information Center

Banning, James H.; Kuk, Linda

2009-01-01

The purpose of this study was to examine dissertations over the past five years that focused on student affairs organizational issues. A bounded qualitative meta-study was used and the methods, theories, and findings of the dissertations were examined. A variety of research methods were used including quantitative, qualitative and mixed designs.…

Assessment Accommodations on Tests of Academic Achievement for Students Who Are Deaf or Hard of Hearing: A Qualitative Meta-Analysis of the Research Literature

ERIC Educational Resources Information Center

Cawthon, Stephanie; Leppo, Rachel

2013-01-01

The authors conducted a qualitative meta-analysis of the research on assessment accommodations for students who are deaf or hard of hearing. There were 16 identified studies that analyzed the impact of factors related to student performance on academic assessments across different educational settings, content areas, and types of assessment…

Meta-Analysis: An Approach to Interview Success.

ERIC Educational Resources Information Center

McCaslin, Mark; Carlson, Nancy M.

An initial research step, developing an effective interview strategy, presents unique challenges for novice and master research alike. To focus qualitative research in the human ecology of the study, the strategy presented in this paper used an initial interview protocol and preanalysis process, called meta-analysis, prior to developing the formal…

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

PubMed

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

Postsecondary study and mental ill-health: a meta-synthesis of qualitative research exploring students' lived experiences.

PubMed

Ennals, Priscilla; Fossey, Ellie; Howie, Linsey

2015-04-01

The postsecondary educational experiences of students living with mental health issues are not well understood. Existing studies are generally qualitative, small and context-specific in nature, and individually have limited influence on policy and practice. To identify and synthesise the findings of qualitative studies exploring student views of studying while living with mental ill-health. A systematic search of six electronic databases including CINAHL, ERIC, PsycINFO and Medline up to March 2013 was conducted. Findings were extracted from included studies and combined using qualitative meta-synthesis to identify core processes. The search identified 16 studies from five countries, with a total of 231 participants. Meta-synthesis of the findings revealed three common core processes: (1) knowing oneself and managing one's mental illness, (2) negotiating the social space, and (3) doing the academic work required for successful postsecondary participation. Beyond the learning processes that underpin studying, these findings suggest knowing oneself and negotiating social spaces of educational settings are key processes for students living with mental ill-health seeking to survive and thrive in postsecondary education. With increased awareness of these processes, students and policy makers may conceive new ways to optimise student experiences of postsecondary study.

A qualitative meta-summary using Sandelowski and Barroso's method for integrating qualitative research to explore barriers and facilitators to self-care in heart failure patients.

PubMed

Herber, Oliver Rudolf; Bücker, Bettina; Metzendorf, Maria-Inti; Barroso, Julie

2017-12-01

Individual qualitative studies provide varied reasons for why heart failure patients do not engage in self-care, yet articles that aggregated primary studies on the subject have methodological weaknesses that justified the execution of a qualitative meta-summary. The aim of this study is to integrate the findings of qualitative studies pertaining to barriers and facilitators to self-care using meta-summary techniques. Qualitative meta-summary techniques by Sandelowski and Barroso were used to combine the findings of qualitative studies. Meta-summary techniques include: (1) extraction of relevant statements of findings from each report; (2) reduction of these statements into abstracted findings and (3) calculation of effect sizes. Databases were searched systematically for qualitative studies published between January 2010 and July 2015. Out of 2264 papers identified, 31 reports based on the accounts of 814 patients were included in the meta-summary. A total of 37 statements of findings provided a comprehensive inventory of findings across all reports. Out of these statements of findings, 21 were classified as barriers, 13 as facilitators and three were classed as both barriers and facilitators. The main themes relating to barriers and facilitators to self-care were: beliefs, benefits of self-care, comorbidities, financial constraints, symptom recognition, ethnic background, inconsistent self-care, insufficient information, positive and negative emotions, organizational context, past experiences, physical environment, self-initiative, self-care adverse effects, social context and personal preferences. Based on the meta-findings identified in this study, future intervention development could address these barriers and facilitators in order to further enhance self-care abilities in heart failure patients.

Work environments and HIV prevention: a qualitative review and meta-synthesis of sex worker narratives.

PubMed

Goldenberg, Shira M; Duff, Putu; Krusi, Andrea

2015-12-16

Sex workers (SWs) experience a disproportionately high burden of HIV, with evidence indicating that complex and dynamic factors within work environments play a critical role in mitigating or producing HIV risks in sex work. In light of sweeping policy efforts to further criminalize sex work globally, coupled with emerging calls for structural responses situated in labour and human-rights frameworks, this meta-synthesis of the qualitative and ethnographic literature sought to examine SWs' narratives to elucidate the ways in which physical, social and policy features of diverse work environments influence SWs' agency to engage in HIV prevention. We conducted a meta-synthesis of qualitative and ethnographic studies published from 2008 to 2014 to elucidate SWs' narratives and lived experiences of the complex and nuanced ways in which physical, social, and policy features of indoor and outdoor work environments shape HIV prevention in the sex industry. Twenty-four qualitative and/or ethnographic studies were included in this meta-synthesis. SWs' narratives revealed the nuanced ways that physical, social, and policy features of work environments shaped HIV risk and interacted with macrostructural constraints (e.g., criminalization, stigma) and community determinants (e.g., sex worker empowerment initiatives) to shape SWs' agency in negotiating condom use. SWs' narratives revealed the ways in which the existence of occupational health and safety standards in indoor establishments, as well as protective practices of third parties (e.g., condom promotion) and other SWs/peers were critical ways of enhancing safety and sexual risk negotiation within indoor work environments. Additionally, working in settings where negative interactions with law enforcement were minimized (e.g., working in decriminalized contexts or environments in which peers/managers successfully deterred unjust policing practices) was critical for supporting SWs' agency to negotiate HIV prevention. Policy

Meta-analysis of human gene expression in response to Mycobacterium tuberculosis infection reveals potential therapeutic targets.

PubMed

Wang, Zhang; Arat, Seda; Magid-Slav, Michal; Brown, James R

2018-01-10

With the global emergence of multi-drug resistant strains of Mycobacterium tuberculosis, new strategies to treat tuberculosis are urgently needed such as therapeutics targeting potential human host factors. Here we performed a statistical meta-analysis of human gene expression in response to both latent and active pulmonary tuberculosis infections from nine published datasets. We found 1655 genes that were significantly differentially expressed during active tuberculosis infection. In contrast, no gene was significant for latent tuberculosis. Pathway enrichment analysis identified 90 significant canonical human pathways, including several pathways more commonly related to non-infectious diseases such as the LRRK2 pathway in Parkinson's disease, and PD-1/PD-L1 signaling pathway important for new immuno-oncology therapies. The analysis of human genome-wide association studies datasets revealed tuberculosis-associated genetic variants proximal to several genes in major histocompatibility complex for antigen presentation. We propose several new targets and drug-repurposing opportunities including intravenous immunoglobulin, ion-channel blockers and cancer immuno-therapeutics for development as combination therapeutics with anti-mycobacterial agents. Our meta-analysis provides novel insights into host genes and pathways important for tuberculosis and brings forth potential drug repurposing opportunities for host-directed therapies.

Meta-synthesis on nurse practitioner autonomy and roles in ambulatory care.

PubMed

Wang-Romjue, Pauline

2018-04-01

Many healthcare stakeholders view nurse practitioners (NPs) as an important workforce resource to help fill the anticipated shortage of 20,400 ambulatory care physicians that is expected by 2020. Multiple quantitative studies revealed the attributes of NPs' practice autonomy and roles. However, there is no qualitative meta-synthesis that describes the experiences of NPs' practice autonomy and roles. To describe and understand the experiences of NPs regarding their practice autonomy and roles in various ambulatory settings through the exploration of existing qualitative studies: meta-synthesis. A qualitative meta-synthesis was conducted to gain insight into ambulatory NPs' practice autonomy and roles through content analysis and reciprocal translation. Articles published between 2000 and 2017 were retrieved by searching 7 databases using the following key words: U.S. qualitative studies, advance practice nurses, NP role in ambulatory care, NP autonomy, and outpatient care. Autonomy, NPs' roles and responsibilities, practice relationships, and organizational work environment pressures are the four main themes that emerged from the content analysis of the nine selected qualitative studies. Within and between states, NPs' experiences with autonomy and NPs' roles are multifaceted depending on state regulations, practice relationships, and organizational work environments. © 2017 Wiley Periodicals, Inc.

Impact of platform switching on marginal peri-implant bone-level changes. A systematic review and meta-analysis

PubMed Central

Strietzel, Frank Peter; Neumann, Konrad; Hertel, Moritz

2015-01-01

Objective To address the focused question, is there an impact of platform switching (PS) on marginal bone level (MBL) changes around endosseous implants compared to implants with platform matching (PM) implant-abutment configurations? Material and methods A systematic literature search was conducted using electronic databases PubMed, Web of Science, Journals@Ovid Full Text and Embase, manual search for human randomized clinical trials (RCTs) and prospective clinical controlled cohort studies (PCCS) reporting on MBL changes at implants with PS-, compared with PM-implant-abutment connections, published between 2005 and June 2013. Results Twenty-two publications were eligible for the systematic review. The qualitative analysis of 15 RCTs and seven PCCS revealed more studies (13 RCTs and three PCCS) showing a significantly less mean marginal bone loss around implants with PS- compared to PM-implant-abutment connections, indicating a clear tendency favoring the PS technique. A meta-analysis including 13 RCTs revealed a significantly less mean MBL change (0.49 mm [CI95% 0.38; 0.60]) at PS implants, compared with PM implants (1.01 mm [CI95% 0.62; 1.40] (P < 0.0001). Conclusions The meta-analysis revealed a significantly less mean MBL change at implants with a PS compared to PM-implant-abutment configuration. Studies included herein showed an unclear as well as high risk of bias mostly, and relatively short follow-up periods. The qualitative analysis revealed a tendency favoring the PS technique to prevent or minimize peri-implant marginal bone loss compared with PM technique. Due to heterogeneity of the included studies, their results require cautious interpretation. PMID:24438506

Comprehensive Gene expression meta-analysis and integrated bioinformatic approaches reveal shared signatures between thrombosis and myeloproliferative disorders

PubMed Central

Jha, Prabhash Kumar; Vijay, Aatira; Sahu, Anita; Ashraf, Mohammad Zahid

2016-01-01

Thrombosis is a leading cause of morbidity and mortality in patients with myeloproliferative disorders (MPDs), particularly polycythemia vera (PV) and essential thrombocythemia (ET). Despite the attempts to establish a link between them, the shared biological mechanisms are yet to be characterized. An integrated gene expression meta-analysis of five independent publicly available microarray data of the three diseases was conducted to identify shared gene expression signatures and overlapping biological processes. Using INMEX bioinformatic tool, based on combined Effect Size (ES) approaches, we identified a total of 1,157 differentially expressed genes (DEGs) (697 overexpressed and 460 underexpressed genes) shared between the three diseases. EnrichR tool’s rich library was used for comprehensive functional enrichment and pathway analysis which revealed “mRNA Splicing” and “SUMO E3 ligases SUMOylate target proteins” among the most enriched terms. Network based meta-analysis identified MYC and FN1 to be the most highly ranked hub genes. Our results reveal that the alterations in biomarkers of the coagulation cascade like F2R, PROS1, SELPLG and ITGB2 were common between the three diseases. Interestingly, the study has generated a novel database of candidate genetic markers, pathways and transcription factors shared between thrombosis and MPDs, which might aid in the development of prognostic therapeutic biomarkers. PMID:27892526

Meta-Ethnography of Qualitative Research on the Experience of Being a Partner to an Individual with Schizophrenia Spectrum Disorder.

PubMed

Lewis, Laura Foran

2017-03-01

Several qualitative studies explore the experience of being a partner to an individual with schizophrenia spectrum disorder, but these studies remain isolated "islands of knowledge." This meta-ethnography aimed to synthesize current qualitative studies using Noblit and Hare's method. Thirteen studies were identified for inclusion. Three overarching themes were revealed: unmet expectations of relationship, renegotiating relationship roles, and separation versus togetherness. Themes interacted as a cycle with separation versus togetherness as temporal endpoints. Partners also renegotiated relationships with mental health professionals to accommodate unmet expectations. Leverage points for intervention were identified.

Word-wide meta-analysis of Quercus forests ectomycorrhizal fungal diversity reveals southwestern Mexico as a hotspot.

PubMed

García-Guzmán, Olimpia Mariana; Garibay-Orijel, Roberto; Hernández, Edith; Arellano-Torres, Elsa; Oyama, Ken

2017-11-01

Quercus is the most diverse genus of ectomycorrhizal (ECM) host plants; it is distributed in the Northern and Southern Hemispheres, from temperate to tropical regions. However, their ECM communities have been scarcely studied in comparison to those of conifers. The objectives of this study were to determine the richness of ECM fungi associated with oak forests in the Cuitzeo basin in southwestern Mexico; and to determine the level of richness, potential endemism and species similarity among ECM fungal communities associated with natural oak forests worldwide through a meta-analysis. The ITS DNA sequences of ECM root tips from 14 studies were included in the meta-analysis. In total, 1065 species of ECM fungi have been documented worldwide; however, 812 species have been only found at one site. Oak forests in Europe contain 416 species, Mexico 307, USA 285, and China 151. Species with wider distributions are Sebacinaceae sp. SH197130, Amanita subjunquillea, Cenococcum geophilum, Cortinarius decipiens, Russula hortensis, R. risigallina, R. subrubescens, Sebacinaceae sp. SH214607, Tomentella ferruginea, and T. lapida. The meta-analysis revealed (1) that Mexico is not only a hotspot for oak species but also for their ECM mycobionts. (2) There is a particularly high diversity of ECM Pezizales in oak seasonal forests from western USA to southwestern Mexico. (3) The oak forests in southwestern Mexico have the largest number of potential endemic species. (4) Globally, there is a high turnover of ECM fungal species associated with oaks, which indicates high levels of alpha and beta diversity in these communities.

Revisiting a Meta-Analysis of Helpful Aspects of Therapy in a Community Counselling Service

ERIC Educational Resources Information Center

Quick, Emma L; Dowd, Claire; Spong, Sheila

2018-01-01

This small scale mixed methods study examines helpful events in a community counselling setting, categorising impacts of events according to Timulak's [(2007). Identifying core categories of client-identified impact of helpful events in psychotherapy: A qualitative meta-analysis. "Psychotherapy Research," 17, 305-314] meta-synthesis of…

Physical Activity and Quality of Life in Cancer Survivors: A Meta-Synthesis of Qualitative Research

PubMed Central

Burke, Shaunna; Wurz, Amanda; Bradshaw, Andrew; Saunders, Stephanie; West, Malcolm A.; Brunet, Jennifer

2017-01-01

Qualitative research on the impact of physical activity on quality of life (QoL) in adults diagnosed with cancer is accumulating. However, the field of physical activity and cancer survivorship lack a synthesis of this research to reliably understand the implications for future research and practice. The aim of this meta-synthesis was to identify, appraise, and synthesize qualitative research on cancer survivors’ perspectives of the impact of physical activity on their QoL. Seven electronic databases were searched for original studies published in English, and reference lists of relevant studies were hand-searched to identify additional studies. Forty studies met eligibility criteria and were included in this meta-synthesis. Study characteristics and major findings were extracted, and findings were summarized, compared, and synthesized. Themes identified in this review revealed that physical activity positively impacted four dimensions of cancer survivors’ QoL: physical (e.g., managing the physical consequences of cancer and its treatment), psychological (e.g., evoking positive self-perceptions), social (e.g., feeling understood by others), and spiritual (e.g., redefining life purpose). This meta-synthesis corroborates conclusions from reviews of quantitative research and illustrates that physical activity can be used to improve QoL in adult cancer survivors, regardless of diagnosis (i.e., stage, cancer type) and treatment status. It also provides detailed insight into specific aspects within each dimension of QoL impacted by physical activity from cancer survivors’ perspectives, which is important for understanding the meaning and utility of physical activity for them. However, more research is needed to further develop the qualitative evidence base in order to better understand how physical activity impacts on QoL experiences in men, young adults, and adults diagnosed with less common types of cancer at different points along cancer trajectory (i

Physical Activity and Quality of Life in Cancer Survivors: A Meta-Synthesis of Qualitative Research.

PubMed

Burke, Shaunna; Wurz, Amanda; Bradshaw, Andrew; Saunders, Stephanie; West, Malcolm A; Brunet, Jennifer

2017-05-20

Qualitative research on the impact of physical activity on quality of life (QoL) in adults diagnosed with cancer is accumulating. However, the field of physical activity and cancer survivorship lack a synthesis of this research to reliably understand the implications for future research and practice. The aim of this meta-synthesis was to identify, appraise, and synthesize qualitative research on cancer survivors' perspectives of the impact of physical activity on their QoL. Seven electronic databases were searched for original studies published in English, and reference lists of relevant studies were hand-searched to identify additional studies. Forty studies met eligibility criteria and were included in this meta-synthesis. Study characteristics and major findings were extracted, and findings were summarized, compared, and synthesized. Themes identified in this review revealed that physical activity positively impacted four dimensions of cancer survivors' QoL: physical (e.g., managing the physical consequences of cancer and its treatment), psychological (e.g., evoking positive self-perceptions), social (e.g., feeling understood by others), and spiritual (e.g., redefining life purpose). This meta-synthesis corroborates conclusions from reviews of quantitative research and illustrates that physical activity can be used to improve QoL in adult cancer survivors, regardless of diagnosis (i.e., stage, cancer type) and treatment status. It also provides detailed insight into specific aspects within each dimension of QoL impacted by physical activity from cancer survivors' perspectives, which is important for understanding the meaning and utility of physical activity for them. However, more research is needed to further develop the qualitative evidence base in order to better understand how physical activity impacts on QoL experiences in men, young adults, and adults diagnosed with less common types of cancer at different points along cancer trajectory (i.e., diagnosis

Assessment accommodations on tests of academic achievement for students who are deaf or hard of hearing: a qualitative meta-analysis of the research literature.

PubMed

Cawthon, Stephanie; Leppo, Rachel

2013-01-01

The authors conducted a qualitative meta-analysis of the research on assessment accommodations for students who are deaf or hard of hearing. There were 16 identified studies that analyzed the impact of factors related to student performance on academic assessments across different educational settings, content areas, and types of assessment accommodations. The meta-analysis found that the results of analyses of group effects of accommodated versus unaccommodated test formats are often not significant, test-level factors exist that can affect how students perceive the assessments, and differences exist in how test items function across different conditions. Student-level factors, including educational context and academic proficiency, influence accommodations' role in assessment processes. The results of this analysis highlight the complexity of and intersections between student-level factors, test-level factors, and larger policy contexts. Findings are discussed within the context of larger changes in academic assessment, including computer-based administration and high-stakes testing.

STEM Education Related Dissertation Abstracts: A Bounded Qualitative Meta-Study

ERIC Educational Resources Information Center

Banning, James; Folkestad, James E.

2012-01-01

This article utilizes a bounded qualitative meta-study framework to examine the 101 dissertation abstracts found by searching the ProQuest Dissertation and Theses[TM] digital database for dissertations abstracts from 1990 through 2010 using the search terms education, science, technology, engineer, and STEM/SMET. Professional search librarians…

Researching children's perspectives in pediatric palliative care: A systematic review and meta-summary of qualitative research.

PubMed

Ghirotto, Luca; Busani, Elena; Salvati, Michela; Di Marco, Valeria; Caldarelli, Valeria; Artioli, Giovanna

2018-05-29

Qualitative research is pivotal in gaining understanding of individuals' experiences in pediatric palliative care. In the past few decades, the number of qualitative studies on pediatric palliative care has increased slightly, as has interest in qualitative research in this area. Nonetheless, a limited number of such studies have included the first-person perspective of children. The aim of this article is to understand the contribution of previous qualitative research on pediatric palliative care that included the voices of children. A systematic review of qualitative studies and a meta-summary were conducted. MEDLINE, CINAHL, PsycINFO, PsycARTICLES, and ERIC were searched without limitations on publication date or language. Eligible articles were qualitative research articles in which the participants were children ranging in age from 3 to 18 years.ResultWe retrieved 16 qualitative research articles reporting on 12 unique studies, and we selected two mixed-method articles. The meta-summary shows eight themes: the relationship with professional caregivers, pain and its management, "living beyond pain," the relationship between pediatric patients and their families, children's view on their treatment and service provision, meanings children give to their end-of-life situation, consequences of clinical decisions, and the relationships among children in pediatric palliative care and their peers.Significance of resultsThis meta-summary presents the "state of the art" of pediatric palliative care qualitative research on children and highlights additional research areas that warrant qualitative study.

How to Perform a Systematic Review and Meta-analysis of Diagnostic Imaging Studies.

PubMed

Cronin, Paul; Kelly, Aine Marie; Altaee, Duaa; Foerster, Bradley; Petrou, Myria; Dwamena, Ben A

2018-05-01

A systematic review is a comprehensive search, critical evaluation, and synthesis of all the relevant studies on a specific (clinical) topic that can be applied to the evaluation of diagnostic and screening imaging studies. It can be a qualitative or a quantitative (meta-analysis) review of available literature. A meta-analysis uses statistical methods to combine and summarize the results of several studies. In this review, a 12-step approach to performing a systematic review (and meta-analysis) is outlined under the four domains: (1) Problem Formulation and Data Acquisition, (2) Quality Appraisal of Eligible Studies, (3) Statistical Analysis of Quantitative Data, and (4) Clinical Interpretation of the Evidence. This review is specifically geared toward the performance of a systematic review and meta-analysis of diagnostic test accuracy (imaging) studies. Copyright © 2018 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

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

ERIC Educational Resources Information Center

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…

The experience of nurses in care for culturally diverse families: A qualitative meta-synthesis 1

PubMed Central

Murcia, Saidy Eliana Arias; Lopez, Lucero

2016-01-01

Abstract Objective: to understand the experience of nurses in care delivery to culturally diverse families. Method: qualitative meta-synthesis. Exhaustive search in seven databases, three repositories and a manual search in references without time limit, in English, Spanish and Portuguese, resulting in 1609 potentially relevant studies. These were assessed based on the title, summary and full text, determining the final inclusion of 14 studies. Two independent reviewers used the Critical Appraisal Skills Programme (CASP) to assess the quality. The interpretative synthesis implied permanent contrast and consensus among the authors, revealing four categories and one meta-theme. Results: "taking care of a culturally diverse family, the experience of crossing a tightrope". Conclusion: the experience of nurses in care delivery to culturally diverse families is demanding and challenging because it imprints a constant tension among barriers, cultural manifestations and the ethical responsibility of care, incipiently revealing elements of cultural competency. The omission of information in the participants' reports in the studies represents a limitation. The findings offer a baseline for professionals and organizations to focus their intervention efforts on the continuing barriers in care delivery to culturally diverse families and strengthens the need for cultural competency training for nurses. PMID:27384469

A Qualitative Meta-Synthesis of Interpersonal Violence Prevention Programs Focused on Males.

PubMed

Taliep, Naiema; Lazarus, Sandy; Naidoo, Anthony V

2017-12-01

Exceptionally high levels of interpersonal violence have triggered a call by many experts for the need to determine effective ways to address the onset and effects of exposure to interpersonal violence. The specific aim of this study was to identify and draw on existing promising practices to make a more informed decision on strategies to develop a contextually relevant intervention that focused on the promotion of positive forms of masculinity to create safety and peace. This study used a qualitative meta-synthesis (QMS) technique to integrate and interpret findings from various intervention studies that focused on males and/or gender. An in-depth literature search yielded a total of 827 papers that met the search criteria. After removal of duplicates, abstract review, and review of the full texts, the subsequent sample for this meta-synthesis included 12 intervention programs and 23 studies. This QMS revealed the value of a comprehensive approach, using multiple strategies, employing participatory and interactive methods, and promoting social mobilization to address interpersonal violence. The promotion of positive forms of masculinity as an interpersonal violence prevention strategy is a much-needed, relatively untapped approach to generating safety and peace for both males and females.

Meta-analysis of chicken--salmonella infection experiments.

PubMed

Te Pas, Marinus F W; Hulsegge, Ina; Schokker, Dirkjan; Smits, Mari A; Fife, Mark; Zoorob, Rima; Endale, Marie-Laure; Rebel, Johanna M J

2012-04-24

Chicken meat and eggs can be a source of human zoonotic pathogens, especially Salmonella species. These food items contain a potential hazard for humans. Chickens lines differ in susceptibility for Salmonella and can harbor Salmonella pathogens without showing clinical signs of illness. Many investigations including genomic studies have examined the mechanisms how chickens react to infection. Apart from the innate immune response, many physiological mechanisms and pathways are reported to be involved in the chicken host response to Salmonella infection. The objective of this study was to perform a meta-analysis of diverse experiments to identify general and host specific mechanisms to the Salmonella challenge. Diverse chicken lines differing in susceptibility to Salmonella infection were challenged with different Salmonella serovars at several time points. Various tissues were sampled at different time points post-infection, and resulting host transcriptional differences investigated using different microarray platforms. The meta-analysis was performed with the R-package metaMA to create lists of differentially regulated genes. These gene lists showed many similarities for different chicken breeds and tissues, and also for different Salmonella serovars measured at different times post infection. Functional biological analysis of these differentially expressed gene lists revealed several common mechanisms for the chicken host response to Salmonella infection. The meta-analysis-specific genes (i.e. genes found differentially expressed only in the meta-analysis) confirmed and expanded the biological functional mechanisms. The meta-analysis combination of heterogeneous expression profiling data provided useful insights into the common metabolic pathways and functions of different chicken lines infected with different Salmonella serovars.

Comprehensive meta-analysis reveals association between multiple imprinting disorders and conception by assisted reproductive technology.

PubMed

Cortessis, Victoria K; Azadian, Moosa; Buxbaum, James; Sanogo, Fatimata; Song, Ashley Y; Sriprasert, Intira; Wei, Pengxiao C; Yu, Jing; Chung, Karine; Siegmund, Kimberly D

2018-04-25

To determine whether a history of conception by assisted reproductive technology (ART) is associated with occurrence of one or more imprinting disorders of either maternal or paternal origin. We implemented a systematic review of scholarly literature followed by comprehensive meta-analysis to quantitatively synthesize data from reports relating to use of ART to occurrence of any imprinting disorder of humans, including Beckwith-Wiedemann (BWS), Angelman (AS), Prader-Willi (PWS), and Silver-Russell (SRS) syndromes, as well as transient neonatal diabetes mellitus (TNDB) and sporadic retinoblasoma (RB). The systematic review identified 13 reports presenting unique data from 23 studies that related conception following ART to occurrence of imprinting disorders. Multiple studies of four disorder were identified, for which meta-analysis yielded the following summary estimates of associations with a history of ART: AS, summary odds ratio (sOR) = 4.7 (95% confidence interval (CI) 2.6-8.5, 4 studies); BWS, sOR = 5.8 (95% CI 3.1-11.1, 8 studies); PWS, sOR = 2.2 (95% CI 1.6-3.0, 6 studies); SRS, sOR = 11.3 (95% CI 4.5-28.5, 3 studies). Only one study reported on each of TNDB and RB. Published data reveal positive associations between history of ART conception and each of four imprinting disorders. Reasons for these associations warrant further investigation.

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

PubMed

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.

Abutment Disconnection/Reconnection Affects Peri-implant Marginal Bone Levels: A Meta-Analysis.

PubMed

Koutouzis, Theofilos; Gholami, Fatemeh; Reynolds, John; Lundgren, Tord; Kotsakis, Georgios A

Preclinical and clinical studies have shown that marginal bone loss can be secondary to repeated disconnection and reconnection of abutments that affect the peri-implant mucosal seal. The aim of this systematic review and meta-analysis was to evaluate the impact of abutment disconnections/reconnections on peri-implant marginal bone level changes. To address this question, two reviewers independently performed an electronic search of three major databases up to October 2015 complemented by manual searches. Eligible articles were selected on the basis of prespecified inclusion and exclusion criteria after a two-phase search strategy and assessed for risk of bias. A random-effects meta-analysis was performed for marginal bone loss. The authors initially identified 392 titles and abstracts. After evaluation, seven controlled clinical studies were included. Qualitative assessment of the articles revealed a trend toward protective marginal bone level preservation for implants with final abutment placement (FAP) at the time of implant placement compared with implants for which there were multiple abutment placements (MAP). The FAP group exhibited a marginal bone level change ranging from 0.08 to 0.34 mm, whereas the MAP group exhibited a marginal bone level change ranging from 0.09 to 0.55 mm. Meta-analysis of the seven studies reporting on 396 implants showed significantly greater bone loss in cases of multiple abutment disconnections/reconnections. The weighted mean difference in marginal bone loss was 0.19 mm (95% confidence interval, 0.06-0.32 mm), favoring bone preservation in the FAP group. Within the limitations of this meta-analysis, abutment disconnection and reconnection significantly affected peri-implant marginal bone levels. These findings pave the way for revisiting current restorative protocols at the restorative treatment planning stage to prevent incipient marginal bone loss.

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

PubMed

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 (P<0.0001). The increasing numbers, intensively global influence and high citations revealed that the meta-analysis 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.

Can Anyone Hear Me? Does Anyone See Me? A Qualitative Meta-Analysis of Women's Experiences of Heart Disease.

PubMed

Galick, Aimee; D'Arrigo-Patrick, Elizabeth; Knudson-Martin, Carmen

2015-08-01

Female heart patients are underdiagnosed and undertreated. The purpose of this qualitative meta-data-analysis was to explain how societal expectations related to gender and the treatment environment influence women's experiences and can inform optimal care. The authors used grounded theory methodology and a social constructionist gender lens to analyze 43 studies (1993-2012) of women's experiences of heart disease. The analysis illustrates how social expectations within both medical and relational contexts led to women experiencing barriers to diagnosis and treatment and inadvertent minimization of their experience and knowledge. Women's descriptions of their experiences suggest three kinds of health care strategies that have the potential to increase women's engagement with heart disease treatment and rehabilitation: (a) support give and take in relational connections, (b) identify and acknowledge unique health-promoting behavior, and (c) focus on empowerment. These findings have interdisciplinary implications for practice with women with heart disease. © The Author(s) 2015.

Capturing the experiences of patients across multiple complex interventions: a meta-qualitative approach

PubMed Central

Webster, Fiona; Christian, Jennifer; Mansfield, Elizabeth; Bhattacharyya, Onil; Hawker, Gillian; Levinson, Wendy; Naglie, Gary; Pham, Thuy-Nga; Rose, Louise; Schull, Michael; Sinha, Samir; Stergiopoulos, Vicky; Upshur, Ross; Wilson, Lynn

2015-01-01

Objectives The perspectives, needs and preferences of individuals with complex health and social needs can be overlooked in the design of healthcare interventions. This study was designed to provide new insights on patient perspectives drawing from the qualitative evaluation of 5 complex healthcare interventions. Setting Patients and their caregivers were recruited from 5 interventions based in primary, hospital and community care in Ontario, Canada. Participants We included 62 interviews from 44 patients and 18 non-clinical caregivers. Intervention Our team analysed the transcripts from 5 distinct projects. This approach to qualitative meta-evaluation identifies common issues described by a diverse group of patients, therefore providing potential insights into systems issues. Outcome measures This study is a secondary analysis of qualitative data; therefore, no outcome measures were identified. Results We identified 5 broad themes that capture the patients’ experience and highlight issues that might not be adequately addressed in complex interventions. In our study, we found that: (1) the emergency department is the unavoidable point of care; (2) patients and caregivers are part of complex and variable family systems; (3) non-medical issues mediate patients’ experiences of health and healthcare delivery; (4) the unanticipated consequences of complex healthcare interventions are often the most valuable; and (5) patient experiences are shaped by the healthcare discourses on medically complex patients. Conclusions Our findings suggest that key assumptions about patients that inform intervention design need to be made explicit in order to build capacity to better understand and support patients with multiple chronic diseases. Across many health systems internationally, multiple models are being implemented simultaneously that may have shared features and target similar patients, and a qualitative meta-evaluation approach, thus offers an opportunity for cumulative

Meta-analysis to determine the effects of plant disease management measures: review and case studies on soybean and apple.

PubMed

Ngugi, Henry K; Esker, Paul D; Scherm, Harald

2011-01-01

in epidemiology and disease management is illustrated with case studies from our work on Phakopsora pachyrhizi on soybean and Erwinia amylovora on apple. We show that although meta-analyses are often used to corroborate and validate general conclusions drawn from more traditional, qualitative reviews, they can also reveal new patterns and interpretations not obvious from individual studies.

Sustained Attention in Children with Primary Language Impairment: A Meta-Analysis

PubMed Central

Ebert, Kerry Danahy; Kohnert, Kathryn

2014-01-01

Purpose This study provides a meta-analysis of the difference between children with primary or specific language impairment (LI) and their typically developing peers on tasks of sustained attention. The meta-analysis seeks to determine if children with LI demonstrate subclinical deficits in sustained attention and, if so, under what conditions. Methods Articles that reported empirical data from the performance of children with LI, in comparison to typically developing peers, on a task assessing sustained attention were considered for inclusion. Twenty-eight effect sizes were included in the meta-analysis. Two moderator analyses addressed the effects of stimulus modality and ADHD exclusion. In addition, reaction time outcomes and the effects of task variables were summarized qualitatively. Results The meta-analysis supports the existence of sustained attention deficits in children with LI in both auditory and visual modalities, as demonstrated by reduced accuracy compared to typically developing peers. Larger effect sizes are found in tasks that use auditory and linguistic stimuli than in studies that use visual stimuli. Conclusions Future research should consider the role that sustained attention weaknesses play in LI, as well as the implications for clinical and research assessment tasks. Methodological recommendations are summarized. PMID:21646419

Sustained attention in children with primary language impairment: a meta-analysis.

PubMed

Ebert, Kerry Danahy; Kohnert, Kathryn

2011-10-01

This study provides a meta-analysis of the difference between children with primary or specific language impairment (LI) and their typically developing peers on tasks of sustained attention. The meta-analysis seeks to determine whether children with LI demonstrate subclinical deficits in sustained attention and, if so, under what conditions. Articles that reported empirical data from the performance of children with LI, in comparison to typically developing peers, on a task assessing sustained attention were considered for inclusion. Twenty-eight effect sizes were included in the meta-analysis. Two moderator analyses addressed the effects of stimulus modality and attention-deficit/hypereactivity disorder exclusion. In addition, reaction time outcomes and the effects of task variables were summarized qualitatively. The meta-analysis supports the existence of sustained attention deficits in children with LI in both auditory and visual modalities, as demonstrated by reduced accuracy compared with typically developing peers. Larger effect sizes are found in tasks that use auditory-linguistic stimuli than in studies that use visual stimuli. Future research should consider the role that sustained attention weaknesses play in LI as well as the implications for clinical and research assessment tasks. Methodological recommendations are summarized.

A Meta-Analysis of Interventions to Reduce Loneliness

PubMed Central

Masi, Christopher M.; Chen, Hsi-Yuan; Hawkley, Louise C.; Cacioppo, John T.

2013-01-01

Social and demographic trends are placing an increasing number of adults at risk for loneliness, an established risk factor for physical and mental illness. The growing costs of loneliness have led to a number of loneliness reduction interventions. Qualitative reviews have identified four primary intervention strategies: 1) improving social skills, 2) enhancing social support, 3) increasing opportunities for social contact, and 4) addressing maladaptive social cognition. An integrative meta-analysis of loneliness reduction interventions was conducted to quantify the effects of each strategy and to examine the potential role of moderator variables. Results revealed that single group pre-post and non-randomized comparison studies yielded larger mean effect sizes relative to randomized comparison studies. Among studies that used the latter design, the most successful interventions addressed maladaptive social cognition. This is consistent with current theories regarding loneliness and its etiology. Theoretical and methodological issues associated with designing new loneliness reduction interventions are discussed. PMID:20716644

Creativity and Academic Achievement: A Meta-Analysis

ERIC Educational Resources Information Center

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…

Knowledge synthesis methods for integrating qualitative and quantitative data: a scoping review reveals poor operationalization of the methodological steps.

PubMed

Tricco, Andrea C; Antony, Jesmin; Soobiah, Charlene; Kastner, Monika; MacDonald, Heather; Cogo, Elise; Lillie, Erin; Tran, Judy; Straus, Sharon E

2016-05-01

To describe and compare, through a scoping review, emerging knowledge synthesis methods for integrating qualitative and quantitative evidence in health care, in terms of expertise required, similarities, differences, strengths, limitations, and steps involved in using the methods. Electronic databases (e.g., MEDLINE) were searched, and two reviewers independently selected studies and abstracted data for qualitative analysis. In total, 121 articles reporting seven knowledge synthesis methods (critical interpretive synthesis, integrative review, meta-narrative review, meta-summary, mixed studies review, narrative synthesis, and realist review) were included after screening of 17,962 citations and 1,010 full-text articles. Common similarities among methods related to the entire synthesis process, while common differences related to the research question and eligibility criteria. The most common strength was a comprehensive synthesis providing rich contextual data, whereas the most common weakness was a highly subjective method that was not reproducible. For critical interpretive synthesis, meta-narrative review, meta-summary, and narrative synthesis, guidance was not provided for some steps of the review process. Some of the knowledge synthesis methods provided guidance on all steps, whereas other methods were missing guidance on the synthesis process. Further work is needed to clarify these emerging knowledge synthesis methods. Copyright © 2016 Elsevier Inc. All rights reserved.

A guide to understanding meta-analysis.

PubMed

Israel, Heidi; Richter, Randy R

2011-07-01

With the focus on evidence-based practice in healthcare, a well-conducted systematic review that includes a meta-analysis where indicated represents a high level of evidence for treatment effectiveness. The purpose of this commentary is to assist clinicians in understanding meta-analysis as a statistical tool using both published articles and explanations of components of the technique. We describe what meta-analysis is, what heterogeneity is, and how it affects meta-analysis, effect size, the modeling techniques of meta-analysis, and strengths and weaknesses of meta-analysis. Common components like forest plot interpretation, software that may be used, special cases for meta-analysis, such as subgroup analysis, individual patient data, and meta-regression, and a discussion of criticisms, are included.

Meta-analysis of Chicken – Salmonella infection experiments

PubMed Central

2012-01-01

Background Chicken meat and eggs can be a source of human zoonotic pathogens, especially Salmonella species. These food items contain a potential hazard for humans. Chickens lines differ in susceptibility for Salmonella and can harbor Salmonella pathogens without showing clinical signs of illness. Many investigations including genomic studies have examined the mechanisms how chickens react to infection. Apart from the innate immune response, many physiological mechanisms and pathways are reported to be involved in the chicken host response to Salmonella infection. The objective of this study was to perform a meta-analysis of diverse experiments to identify general and host specific mechanisms to the Salmonella challenge. Results Diverse chicken lines differing in susceptibility to Salmonella infection were challenged with different Salmonella serovars at several time points. Various tissues were sampled at different time points post-infection, and resulting host transcriptional differences investigated using different microarray platforms. The meta-analysis was performed with the R-package metaMA to create lists of differentially regulated genes. These gene lists showed many similarities for different chicken breeds and tissues, and also for different Salmonella serovars measured at different times post infection. Functional biological analysis of these differentially expressed gene lists revealed several common mechanisms for the chicken host response to Salmonella infection. The meta-analysis-specific genes (i.e. genes found differentially expressed only in the meta-analysis) confirmed and expanded the biological functional mechanisms. Conclusions The meta-analysis combination of heterogeneous expression profiling data provided useful insights into the common metabolic pathways and functions of different chicken lines infected with different Salmonella serovars. PMID:22531008

The transition from clinician to academic in nursing and allied health: a qualitative meta-synthesis.

PubMed

Murray, Carolyn; Stanley, Mandy; Wright, Shelley

2014-03-01

The meta-synthesis provides a collective qualitative understanding of the transition experience from nursing and allied health clinician to academic. This understanding assists the preparation for those making the transition as well as giving guidance to those who have recently commenced in academia. Published qualitative studies about the transition from clinician to academic were systematically selected in order to integrate their findings in a meta-synthesis. Databases searched were CINAHL, EMBASE, MEDLINE, SCOPUS, 'Education Research Complete', and 'Academic Search Premier'. The search terms used were academ* OR facult* AND transition. The search was further refined by adding the terms qualitative AND clinic* OR practit* OR profession*. Studies were appraised for credibility, neutrality and relevance. Findings along with direct quotes were extracted from the studies and thematic analysis was used within an interpretative framework. Seven studies were included in the meta-synthesis. The included studies were from nursing, physiotherapy, health and social care. The central theme was a shift in identity from clinician to academic which involved a progression through 4 phases over a period of 1- 3years. These phases were; 'feeling new and vulnerable'; 'encountering the unexpected'; 'doing things differently' and 'evolving into an academic'. New academics felt unsettled and uncertain in the initial phases of transition. It is proposed that these challenges are related to difficulty extracting tacit knowledge and immersion in a new culture. The change of values and beliefs to adapt to the new culture require a concurrent identity shift which can take up to three years. Newcomers need collegial and institutional guidance with prioritization of tasks to address the multiplicity of the academic role and avoid frustration and disillusionment. Copyright © 2013 Elsevier Ltd. All rights reserved.

Experiences of chronic low back pain: a meta-ethnography of qualitative research.

PubMed

MacNeela, Padraig; Doyle, Catherine; O'Gorman, David; Ruane, Nancy; McGuire, Brian E

2015-01-01

Chronic low back pain (CLBP) is associated with a number of costly disability-related outcomes. It has received increasing attention from qualitative researchers studying its consequences for personal, social, and health care experiences. As research questions and methods diversify, there is a growing need to integrate findings emerging from these studies. A meta-ethnography was carried out to synthesise the findings of 38 separate qualitative articles published on the subjective experience of CLBP between 1994 and 2011. Studies were identified following a literature search and quality appraisal. Four themes were proposed after a process of translating the meaning of text extracts from the findings sections across all the articles. The themes referred to the undermining influence of pain, its disempowering impact on all levels, unsatisfying relationships with health care professionals, and learning to live with the pain. The findings are dominated by wide-ranging distress and loss but also acknowledge self-determination and resilience. Implications of the meta-ethnography for clinicians and future qualitative research are outlined, including the need to study relatively unexamined facets of subjective experience such as illness trajectory and social identity.

Association between BANK1 polymorphisms and susceptibility to autoimmune diseases: A meta-analysis.

PubMed

Bae, S-C; Lee, Y H

2017-03-31

This study aimed to explore whether BANK1 polymorphisms are associated with susceptibility to autoimmune diseases. We conducted a meta-analysis on the associations between the BANK1 rs10516487, rs3733197, and rs17266594 polymorphisms and autoimmune diseases. Twenty-two articles with a total of 22,684 patients and 36,437 controls were included in the meta-analysis. Meta-analysis revealed a significant association between autoimmune diseases and the BANK1 rs10516487 T allele (OR = 1.161, 95% CI = 1.092-1.275, p = 1.9 × 10-6, heterogeneity p<0.001). The analysis also revealed an association between autoimmune diseases and the BANK1 rs3733197 A allele (OR = 1.178, 95% CI = 1.105-1.256, p = 4.5 × 10-7, heterogeneity p = 0.002) and the rs17266594 T allele (OR = 1.189, 95% CI = 1.073-1.315, p = 0.001, heterogeneity p<0.001). Meta-analysis by autoimmune disease type revealed an association between both systemic lupus erythematosus and systemic sclerosis and the BANK1 rs10516487 T allele (OR = 1.294, 95% CI = 1.232-1.360, p<1.0 × 10-8, heterogeneity p = 0.556; OR = 1.102, 95% CI = 1.027-1.183, p = 0.017, heterogeneity p = 0.048). However, meta-analysis failed to indicate an association between the BANK1 rs10516487 T allele and rheumatoid arthritis (RA; OR = 1.006, 95% CI = 1.956-1.058, p = 0.819). This meta-analysis demonstrates that BANK1 rs10516487, rs3733197, and rs17266594 polymorphisms are associated with susceptibility to autoimmune diseases.

Brain-Derived Neurotrophic Factor Levels in Autism: A Systematic Review and Meta-Analysis.

PubMed

Saghazadeh, Amene; Rezaei, Nima

2017-04-01

Brain-derived neurotrophic factor (BDNF) plays an important role in activity-dependent synaptic plasticity. Altered blood BDNF levels have been frequently identified in people with autism spectrum disorders (ASD). There are however wide discrepancies in the evidence. Therefore, we performed the present systematic review and meta-analysis aimed at qualitative and quantitative synthesis of studies that measured blood BDNF levels in ASD and control subjects. Observational studies were identified through electronic database searching and also hand-searching of reference lists of relevant articles. A total of 183 papers were initially identified for review and eventually twenty studies were included in the meta-analysis. A meta-analysis of blood BDNF in 887 patients with ASD and 901 control subjects demonstrated significantly higher BDNF levels in ASD compared to controls with the SMD of 0.47 (95% CI 0.07-0.86, p = 0.02). In addition subgroup meta-analyses were performed based on the BDNF specimen. The present meta-analysis study led to conclusion that BDNF might play role in autism initiation/ propagation and therefore it can be considered as a possible biomarker of ASD.

Visual Skills and Chinese Reading Acquisition: A Meta-Analysis of Correlation Evidence

ERIC Educational Resources Information Center

Yang, Ling-Yan; Guo, Jian-Peng; Richman, Lynn C.; Schmidt, Frank L.; Gerken, Kathryn C.; Ding, Yi

2013-01-01

This paper used meta-analysis to synthesize the relation between visual skills and Chinese reading acquisition based on the empirical results from 34 studies published from 1991 to 2011. We obtained 234 correlation coefficients from 64 independent samples, with a total of 5,395 participants. The meta-analysis revealed that visual skills as a…

The role of the right temporoparietal junction in attention and social interaction as revealed by ALE meta-analysis

PubMed Central

Rottschy, C.; Oberwelland, E.; Bzdok, D.; Fox, P. T.; Eickhoff, S. B.; Fink, G. R.; Konrad, K.

2016-01-01

The right temporoparietal junction (rTPJ) is frequently associated with different capacities that to shift attention to unexpected stimuli (reorienting of attention) and to understand others’ (false) mental state [theory of mind (ToM), typically represented by false belief tasks]. Competing hypotheses either suggest the rTPJ representing a unitary region involved in separate cognitive functions or consisting of subregions subserving distinct processes. We conducted activation likelihood estimation (ALE) meta-analyses to test these hypotheses. A conjunction analysis across ALE meta-analyses delineating regions consistently recruited by reorienting of attention and false belief studies revealed the anterior rTPJ, suggesting an overarching role of this specific region. Moreover, the anatomical difference analysis unravelled the posterior rTPJ as higher converging in false belief compared with reorienting of attention tasks. This supports the concept of an exclusive role of the posterior rTPJ in the social domain. These results were complemented by meta-analytic connectivity mapping (MACM) and resting-state functional connectivity (RSFC) analysis to investigate whole-brain connectivity patterns in task-constrained and task-free brain states. This allowed for detailing the functional separation of the anterior and posterior rTPJ. The combination of MACM and RSFC mapping showed that the posterior rTPJ has connectivity patterns with typical ToM regions, whereas the anterior part of rTPJ co-activates with the attentional network. Taken together, our data suggest that rTPJ contains two functionally fractionated subregions: while posterior rTPJ seems exclusively involved in the social domain, anterior rTPJ is involved in both, attention and ToM, conceivably indicating an attentional shifting role of this region. PMID:24915964

Meta-ethnography 25 years on: challenges and insights for synthesising a large number of qualitative studies.

PubMed

Toye, Francine; Seers, Kate; Allcock, Nick; Briggs, Michelle; Carr, Eloise; Barker, Karen

2014-06-21

Studies that systematically search for and synthesise qualitative research are becoming more evident in health care, and they can make an important contribution to patient care. Our team was funded to complete a meta-ethnography of patients' experience of chronic musculoskeletal pain. It has been 25 years since Noblit and Hare published their core text on meta-ethnography, and the current health research environment brings additional challenges to researchers aiming to synthesise qualitative research. Noblit and Hare propose seven stages of meta-ethnography which take the researcher from formulating a research idea to expressing the findings. These stages are not discrete but form part of an iterative research process. We aimed to build on the methods of Noblit and Hare and explore the challenges of including a large number of qualitative studies into a qualitative systematic review. These challenges hinge upon epistemological and practical issues to be considered alongside expectations about what determines high quality research. This paper describes our method and explores these challenges. Central to our method was the process of collaborative interpretation of concepts and the decision to exclude original material where we could not decipher a concept. We use excerpts from our research team's reflexive statements to illustrate the development of our methods.

Nursing students experienced personal inadequacy, vulnerability and transformation during their patient care encounter: A qualitative meta-synthesis.

PubMed

Kaldal, Maiken Holm; Kristiansen, Jette; Uhrenfeldt, Lisbeth

2018-05-01

To identify, appraise and synthesize the best available evidence exploring nursing students' experiences of professional patient care encounters in a hospital unit. The Joanna Briggs Institute (JBI) guidelines were followed and a meta-synthesis was conducted. Qualitative research articles were considered for inclusion in the review, and JBI's meta-aggregative approach to synthesizing qualitative evidence was followed. An extensive search for relevant literature was undertaken in scientific databases. Data were extracted from the included research articles, and qualitative research findings were pooled using the Qualitative Assessment and Review Instrument. This involved categorization of findings on the basis of similarity of meaning and aggregation of these categories to produce a comprehensive set of synthesized findings. A total of five research articles met the inclusion criteria and were included in the review. The review process resulted in 46 subcategories that were aggregated into 13 categories. The categories generated four synthesized findings: personal existence; personal learning and development; being a professional fellow human; and clinical learning environment. We meta-synthesized that: Nursing students experienced personal inadequacy, vulnerability and a transformation during their patient care encounter. Copyright © 2018 Elsevier Ltd. All rights reserved.

Promoting influenza vaccination: Insights from a qualitative meta-analysis of 14 years of influenza-related communications research by U.S. Centers for Disease Control and Prevention (CDC)

PubMed Central

Nowak, Glen J.; Sheedy, Kristine; Bursey, Kelli; Smith, Teresa M.; Basket, Michelle

2018-01-01

Introduction A primary mission of the U.S. Centers for Disease Control and Prevention's (CDC) is promoting immunization against seasonal influenza. As with most education efforts, CDCs influenza-related communications are often informed by formative research. Methods A qualitative meta-analysis of 29 unpublished, primarily qualitative CDC-sponsored studies related to flu and flu vaccination knowledge, attitudes and beliefs (KABs). The studies, undertaken between 2000 and 2013, involved focus groups, in-depth interviews, message testing and surveys. Some involved health care professionals, while others involved members of the public, including sub-populations at risk for severe illness. Findings The themes that emerged suggested progress in terms of KABs related to influenza and influenza vaccination, but also the persistence of many barriers to vaccine acceptance. With respect to the public, recurring themes included limited understanding of influenza and immunization recommendations, indications of greater sub-group recognition of the value of flu vaccination, continued resistance to vaccination among many, and overestimation of the effectiveness of non-vaccine measures. Seven cognitive facilitators of vaccination were identified in the studies along with six cognitive barriers. For health care providers, the analysis suggests greater knowledge and more favorable beliefs, but many misperceptions persist and are similar to those held by the public. KABs often differed by type or category of health care provider. Conclusions The themes identified in this qualitative analysis illustrate the difficulty in changing KABs related to influenza and influenza vaccine, particularly on the scope and scale needed to greatly improve uptake. Even with an influenza pandemic and more vaccine options available, public and some health care provider perceptions and beliefs are difficult and slow to change. This meta-analysis does, however, provide important insights from previously

Revealing the association between cerebrovascular accidents and ambient temperature: a meta-analysis.

PubMed

Zorrilla-Vaca, Andrés; Healy, Ryan Jacob; Silva-Medina, Melissa M

2017-05-01

The association between cerebrovascular accidents (CVA) and weather has been described across several studies showing multiple conflicting results. In this paper, we aim to conduct a meta-analysis to further clarify this association, as well as to find the potential sources of heterogeneity. PubMed, EMBASE, and Google Scholar were searched from inception through 2015, for articles analyzing the correlation between the incidence of CVA and temperature. A pooled effect size (ES) was estimated using random effects model and expressed as absolute values. Subgroup analyses by type of CVA were also performed. Heterogeneity and influence of covariates-including geographic latitude of the study site, male percentage, average temperature, and time interval-were assessed by meta-regression analysis. Twenty-six articles underwent full data extraction and scoring. A total of 19,736 subjects with CVA from 12 different countries were included and grouped as ischemic strokes (IS; n = 14,199), intracerebral hemorrhages (ICH; n = 3798), and subarachnoid hemorrhages (SAH; n = 1739). Lower ambient temperature was significantly associated with increase in incidence of overall CVA when using unadjusted (pooled ES = 0.23, P < 0.001) and adjusted data (pooled ES = 0.03, P = 0.003). Subgroup analyses showed that lower temperature has higher impact on the incidence of ICH (pooled ES = 0.34, P < 0.001), than that of IS (pooled ES = 0.22, P < 0.001) and SAH (pooled ES = 0.11, P = 0.012). In meta-regression analysis, the geographic latitude of the study site was the most influencing factor on this association (Z-score = 8.68). Synthesis of the existing data provides evidence supporting that a lower ambient temperature increases the incidence of CVA. Further population-based studies conducted at negative latitudes are needed to clarify the influence of this factor.

Revealing the association between cerebrovascular accidents and ambient temperature: a meta-analysis

NASA Astrophysics Data System (ADS)

Zorrilla-Vaca, Andrés; Healy, Ryan Jacob; Silva-Medina, Melissa M.

2017-05-01

The association between cerebrovascular accidents (CVA) and weather has been described across several studies showing multiple conflicting results. In this paper, we aim to conduct a meta-analysis to further clarify this association, as well as to find the potential sources of heterogeneity. PubMed, EMBASE, and Google Scholar were searched from inception through 2015, for articles analyzing the correlation between the incidence of CVA and temperature. A pooled effect size (ES) was estimated using random effects model and expressed as absolute values. Subgroup analyses by type of CVA were also performed. Heterogeneity and influence of covariates—including geographic latitude of the study site, male percentage, average temperature, and time interval—were assessed by meta-regression analysis. Twenty-six articles underwent full data extraction and scoring. A total of 19,736 subjects with CVA from 12 different countries were included and grouped as ischemic strokes (IS; n = 14,199), intracerebral hemorrhages (ICH; n = 3798), and subarachnoid hemorrhages (SAH; n = 1739). Lower ambient temperature was significantly associated with increase in incidence of overall CVA when using unadjusted (pooled ES = 0.23, P < 0.001) and adjusted data (pooled ES = 0.03, P = 0.003). Subgroup analyses showed that lower temperature has higher impact on the incidence of ICH (pooled ES = 0.34, P < 0.001), than that of IS (pooled ES = 0.22, P < 0.001) and SAH (pooled ES = 0.11, P = 0.012). In meta-regression analysis, the geographic latitude of the study site was the most influencing factor on this association ( Z-score = 8.68). Synthesis of the existing data provides evidence supporting that a lower ambient temperature increases the incidence of CVA. Further population-based studies conducted at negative latitudes are needed to clarify the influence of this factor.

Patient Information Needs and Breast Reconstruction After Mastectomy: A Qualitative Meta-Synthesis.

PubMed

Carr, Tracey L; Groot, Gary; Cochran, David; Holtslander, Lorraine

2018-04-27

Although many women benefit from breast reconstruction after mastectomy, several studies report women's dissatisfaction with the level of information they were provided with before reconstruction. The present meta-synthesis examines the qualitative literature that explores women's experiences of breast reconstruction after mastectomy and highlights women's healthcare information needs. After a comprehensive search of 6 electronic databases (CINAHL, Cochrane Library, EMBASE, MEDLINE, PsycINFO, and Scopus), we followed the methodology for synthesizing qualitative research. The search produced 423 studies, which were assessed against 5 inclusion criteria. A meta-synthesis methodology was used to analyze the data through taxonomic classification and constant targeted comparison. Some 17 studies met the inclusion criteria, and findings from 16 studies were synthesized. The role of the healthcare practitioner is noted as a major influence on women's expectations, and in some instances, women did not feel adequately informed about the outcomes of surgery and the recovery process. In general, women's desire for normality and effective emotional coping shapes their information needs. The information needs of women are better understood after considering women's actual experiences with breast reconstruction. It is important to inform women of the immediate outcomes of reconstruction surgery and the recovery process. In an attempt to better address women's information needs, healthcare practitioners should discover women's initial expectations of reconstruction as a starting point in the consultation. In addition, the research revealed the importance of the nurse navigator in terms of assisting women through the recovery process.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work

Medical Student Research: An Integrated Mixed-Methods Systematic Review and Meta-Analysis

PubMed Central

Amgad, Mohamed; Man Kin Tsui, Marco; Liptrott, Sarah J.; Shash, Emad

2015-01-01

Importance Despite the rapidly declining number of physician-investigators, there is no consistent structure within medical education so far for involving medical students in research. Objective 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. Evidence Review 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. Findings and Conclusions 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

Clients' experiences of treatment and recovery in borderline personality disorder: A meta-synthesis of qualitative studies.

PubMed

Katsakou, Christina; Pistrang, Nancy

2017-01-31

This review synthesized findings from qualitative studies exploring clients' experiences of their treatment for borderline personality disorder (BPD) and their perceptions of recovery. Fourteen studies were identified through searches in three electronic databases. The Critical Appraisal Skills Programme was used to appraise the methodological quality of the studies. Thematic analysis was used to synthesize the findings. The meta-synthesis identified 10 themes, grouped into 3 domains. The first domain, "Areas of change," suggests that clients make changes in four main areas: developing self-acceptance and self-confidence; controlling difficult thoughts and emotions; practising new ways of relating to others; and implementing practical changes and developing hope. The second domain, "Helpful and unhelpful treatment characteristics," highlights treatment elements that either supported or hindered recovery: safety and containment; being cared for and respected; not being an equal partner in treatment; and focusing on change. The third domain, "The nature of change," refers to clients' experience of change as an open-ended journey and a series of achievements and setbacks. The meta-synthesis highlights areas of change experienced by individuals receiving treatment for BPD, and treatment characteristics that they value. However, further research is needed to better understand how these changes are achieved. Clinical or methodological significance summary: The present qualitative meta-synthesis brings together findings from 14 qualitative studies. The emerging themes point to areas of improvement in psychological functioning that people struggling with BPD issues have identified as both important and achievable. They also highlight treatment characteristics that might facilitate change in these areas. Treatments emphasizing these characteristics, namely striking a balance between creating a safe, caring space, and actively promoting change, may increase clients

MetaGenyo: a web tool for meta-analysis of genetic association studies.

PubMed

Martorell-Marugan, Jordi; Toro-Dominguez, Daniel; Alarcon-Riquelme, Marta E; Carmona-Saez, Pedro

2017-12-16

Genetic association studies (GAS) aims to evaluate the association between genetic variants and phenotypes. In the last few years, the number of this type of study has increased exponentially, but the results are not always reproducible due to experimental designs, low sample sizes and other methodological errors. In this field, meta-analysis techniques are becoming very popular tools to combine results across studies to increase statistical power and to resolve discrepancies in genetic association studies. A meta-analysis summarizes research findings, increases statistical power and enables the identification of genuine associations between genotypes and phenotypes. Meta-analysis techniques are increasingly used in GAS, but it is also increasing the amount of published meta-analysis containing different errors. Although there are several software packages that implement meta-analysis, none of them are specifically designed for genetic association studies and in most cases their use requires advanced programming or scripting expertise. We have developed MetaGenyo, a web tool for meta-analysis in GAS. MetaGenyo implements a complete and comprehensive workflow that can be executed in an easy-to-use environment without programming knowledge. MetaGenyo has been developed to guide users through the main steps of a GAS meta-analysis, covering Hardy-Weinberg test, statistical association for different genetic models, analysis of heterogeneity, testing for publication bias, subgroup analysis and robustness testing of the results. MetaGenyo is a useful tool to conduct comprehensive genetic association meta-analysis. The application is freely available at http://bioinfo.genyo.es/metagenyo/ .

Trial Sequential Analysis in systematic reviews with meta-analysis.

PubMed

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

2017-03-06

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). 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. 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 (D 2 ) 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 systematic reviews with traditional meta-analyses can

Human papillomavirus vaccine acceptability and decision-making among adolescent boys and parents: A meta-ethnography of qualitative studies.

PubMed

Lacombe-Duncan, Ashley; Newman, Peter A; Baiden, Philip

2018-05-03

Genital warts and human papillomavirus (HPV)-associated cancers in men can be substantially reduced through HPV vaccination; yet, globally, HPV vaccine uptake among boys remains low. This meta-ethnography synthesizes qualitative studies to understand, in-depth, HPV vaccine acceptability and decision-making among adolescent boys and/or their parents. A systematic search identified qualitative studies examining HPV vaccines from the perspectives of boys and/or boys' parents. The Consolidated Criteria for Reporting Qualitative Research (COREQ) 32-item checklist was used to assess quality of reporting. Using meta-ethnographic techniques, we conducted a structured and iterative process of data analysis, coded original studies, and then developed descriptive and analytic themes to synthesize the findings. Review of 15 eligible studies (n = 3362 parents, n = 39 boys) revealed multilevel factors that influence HPV vaccine acceptability and decision-making among adolescent boys and their parents: (1) individual, e.g., low HPV vaccine knowledge/awareness, (2) interpersonal, e.g., key relationships between parents, sons, and healthcare providers (HCP), (3) community/societal, e.g., parental duty to protect, and (4) systemic, e.g., HPV vaccine messaging. Parents generally accepted adolescent boys' sexuality and the need for vaccination, motivated by wanting to protect their sons from HPV and HPV-associated cancers, and valued HCP-initiated discussion and recommendation. Acceptability was mitigated by low awareness/knowledge of HPV vaccines and low perceived benefits for boys, lack of HCP-initiated discussion, out-of-pocket costs, multiple doses, stigma, and mixed messages about HPV. Multilevel factors influence HPV vaccine acceptability and decision-making among parents and their adolescent sons. Providing clear and unambiguous messages about HPV vaccines-for whom (boys and girls), for what (genital warts and cancers in men), and when (before sexual debut

Child-Staff Ratios in Early Childhood Education and Care Settings and Child Outcomes: A Systematic Review and Meta-Analysis.

PubMed

Perlman, Michal; Fletcher, Brooke; Falenchuk, Olesya; Brunsek, Ashley; McMullen, Evelyn; Shah, Prakesh S

2017-01-01

Child-staff ratios are a key quality indicator in early childhood education and care (ECEC) programs. Better ratios are believed to improve child outcomes by increasing opportunities for individual interactions and educational instruction from staff. The purpose of this systematic review, and where possible, meta-analysis, was to evaluate the association between child-staff ratios in preschool ECEC programs and children's outcomes. Searches of Medline, PsycINFO, ERIC, websites of large datasets and reference sections of all retrieved articles were conducted up to July 3, 2015. Cross-sectional or longitudinal studies that evaluated the relationship between child-staff ratios in ECEC classrooms serving preschool aged children and child outcomes were independently identified by two reviewers. Data were independently extracted from included studies by two raters and differences between raters were resolved by consensus. Searches revealed 29 eligible studies (31 samples). Child-staff ratios ranged from 5 to 14.5 preschool-aged children per adult with a mean of 8.65. All 29 studies were included in the systematic review. However, the only meta-analysis that could be conducted was based on three studies that explored associations between ratios and children's receptive language. Results of this meta-analysis were not significant. Results of the qualitative systematic review revealed few significant relationships between child-staff ratios and child outcomes construed broadly. Thus, the available literature reveal few, if any, relationships between child-staff ratios in preschool ECEC programs and children's developmental outcomes. Substantial heterogeneity in the assessment of ratios, outcomes measured, and statistics used to capture associations limited quantitative synthesis. Other methodological limitations of the research integrated in this synthesis are discussed.

Child-Staff Ratios in Early Childhood Education and Care Settings and Child Outcomes: A Systematic Review and Meta-Analysis

PubMed Central

Perlman, Michal; Fletcher, Brooke; Falenchuk, Olesya; Brunsek, Ashley; McMullen, Evelyn; Shah, Prakesh S.

2017-01-01

Child-staff ratios are a key quality indicator in early childhood education and care (ECEC) programs. Better ratios are believed to improve child outcomes by increasing opportunities for individual interactions and educational instruction from staff. The purpose of this systematic review, and where possible, meta-analysis, was to evaluate the association between child-staff ratios in preschool ECEC programs and children’s outcomes. Searches of Medline, PsycINFO, ERIC, websites of large datasets and reference sections of all retrieved articles were conducted up to July 3, 2015. Cross-sectional or longitudinal studies that evaluated the relationship between child-staff ratios in ECEC classrooms serving preschool aged children and child outcomes were independently identified by two reviewers. Data were independently extracted from included studies by two raters and differences between raters were resolved by consensus. Searches revealed 29 eligible studies (31 samples). Child-staff ratios ranged from 5 to 14.5 preschool-aged children per adult with a mean of 8.65. All 29 studies were included in the systematic review. However, the only meta-analysis that could be conducted was based on three studies that explored associations between ratios and children’s receptive language. Results of this meta-analysis were not significant. Results of the qualitative systematic review revealed few significant relationships between child-staff ratios and child outcomes construed broadly. Thus, the available literature reveal few, if any, relationships between child-staff ratios in preschool ECEC programs and children’s developmental outcomes. Substantial heterogeneity in the assessment of ratios, outcomes measured, and statistics used to capture associations limited quantitative synthesis. Other methodological limitations of the research integrated in this synthesis are discussed. PMID:28103288

Capturing the experiences of patients across multiple complex interventions: a meta-qualitative approach.

PubMed

Webster, Fiona; Christian, Jennifer; Mansfield, Elizabeth; Bhattacharyya, Onil; Hawker, Gillian; Levinson, Wendy; Naglie, Gary; Pham, Thuy-Nga; Rose, Louise; Schull, Michael; Sinha, Samir; Stergiopoulos, Vicky; Upshur, Ross; Wilson, Lynn

2015-09-08

The perspectives, needs and preferences of individuals with complex health and social needs can be overlooked in the design of healthcare interventions. This study was designed to provide new insights on patient perspectives drawing from the qualitative evaluation of 5 complex healthcare interventions. Patients and their caregivers were recruited from 5 interventions based in primary, hospital and community care in Ontario, Canada. We included 62 interviews from 44 patients and 18 non-clinical caregivers. Our team analysed the transcripts from 5 distinct projects. This approach to qualitative meta-evaluation identifies common issues described by a diverse group of patients, therefore providing potential insights into systems issues. This study is a secondary analysis of qualitative data; therefore, no outcome measures were identified. We identified 5 broad themes that capture the patients' experience and highlight issues that might not be adequately addressed in complex interventions. In our study, we found that: (1) the emergency department is the unavoidable point of care; (2) patients and caregivers are part of complex and variable family systems; (3) non-medical issues mediate patients' experiences of health and healthcare delivery; (4) the unanticipated consequences of complex healthcare interventions are often the most valuable; and (5) patient experiences are shaped by the healthcare discourses on medically complex patients. Our findings suggest that key assumptions about patients that inform intervention design need to be made explicit in order to build capacity to better understand and support patients with multiple chronic diseases. Across many health systems internationally, multiple models are being implemented simultaneously that may have shared features and target similar patients, and a qualitative meta-evaluation approach, thus offers an opportunity for cumulative learning at a system level in addition to informing intervention design and

Integrated multi-cohort transcriptional meta-analysis of neurodegenerative diseases.

PubMed

Li, Matthew D; Burns, Terry C; Morgan, Alexander A; Khatri, Purvesh

2014-09-04

Neurodegenerative diseases share common pathologic features including neuroinflammation, mitochondrial dysfunction and protein aggregation, suggesting common underlying mechanisms of neurodegeneration. We undertook a meta-analysis of public gene expression data for neurodegenerative diseases to identify a common transcriptional signature of neurodegeneration. Using 1,270 post-mortem central nervous system tissue samples from 13 patient cohorts covering four neurodegenerative diseases, we identified 243 differentially expressed genes, which were similarly dysregulated in 15 additional patient cohorts of 205 samples including seven neurodegenerative diseases. This gene signature correlated with histologic disease severity. Metallothioneins featured prominently among differentially expressed genes, and functional pathway analysis identified specific convergent themes of dysregulation. MetaCore network analyses revealed various novel candidate hub genes (e.g. STAU2). Genes associated with M1-polarized macrophages and reactive astrocytes were strongly enriched in the meta-analysis data. Evaluation of genes enriched in neurons revealed 70 down-regulated genes, over half not previously associated with neurodegeneration. Comparison with aging brain data (3 patient cohorts, 221 samples) revealed 53 of these to be unique to neurodegenerative disease, many of which are strong candidates to be important in neuropathogenesis (e.g. NDN, NAP1L2). ENCODE ChIP-seq analysis predicted common upstream transcriptional regulators not associated with normal aging (REST, RBBP5, SIN3A, SP2, YY1, ZNF143, IKZF1). Finally, we removed genes common to neurodegeneration from disease-specific gene signatures, revealing uniquely robust immune response and JAK-STAT signaling in amyotrophic lateral sclerosis. Our results implicate pervasive bioenergetic deficits, M1-type microglial activation and gliosis as unifying themes of neurodegeneration, and identify numerous novel genes associated with

Meta-ethnography 25 years on: challenges and insights for synthesising a large number of qualitative studies

PubMed Central

2014-01-01

Studies that systematically search for and synthesise qualitative research are becoming more evident in health care, and they can make an important contribution to patient care. Our team was funded to complete a meta-ethnography of patients’ experience of chronic musculoskeletal pain. It has been 25 years since Noblit and Hare published their core text on meta-ethnography, and the current health research environment brings additional challenges to researchers aiming to synthesise qualitative research. Noblit and Hare propose seven stages of meta-ethnography which take the researcher from formulating a research idea to expressing the findings. These stages are not discrete but form part of an iterative research process. We aimed to build on the methods of Noblit and Hare and explore the challenges of including a large number of qualitative studies into a qualitative systematic review. These challenges hinge upon epistemological and practical issues to be considered alongside expectations about what determines high quality research. This paper describes our method and explores these challenges. Central to our method was the process of collaborative interpretation of concepts and the decision to exclude original material where we could not decipher a concept. We use excerpts from our research team’s reflexive statements to illustrate the development of our methods. PMID:24951054

CNV-association meta-analysis in 191,161 European adults reveals new loci associated with anthropometric traits.

PubMed

Macé, Aurélien; Tuke, Marcus A; Deelen, Patrick; Kristiansson, Kati; Mattsson, Hannele; Nõukas, Margit; Sapkota, Yadav; Schick, Ursula; Porcu, Eleonora; Rüeger, Sina; McDaid, Aaron F; Porteous, David; Winkler, Thomas W; Salvi, Erika; Shrine, Nick; Liu, Xueping; Ang, Wei Q; Zhang, Weihua; Feitosa, Mary F; Venturini, Cristina; van der Most, Peter J; Rosengren, Anders; Wood, Andrew R; Beaumont, Robin N; Jones, Samuel E; Ruth, Katherine S; Yaghootkar, Hanieh; Tyrrell, Jessica; Havulinna, Aki S; Boers, Harmen; Mägi, Reedik; Kriebel, Jennifer; Müller-Nurasyid, Martina; Perola, Markus; Nieminen, Markku; Lokki, Marja-Liisa; Kähönen, Mika; Viikari, Jorma S; Geller, Frank; Lahti, Jari; Palotie, Aarno; Koponen, Päivikki; Lundqvist, Annamari; Rissanen, Harri; Bottinger, Erwin P; Afaq, Saima; Wojczynski, Mary K; Lenzini, Petra; Nolte, Ilja M; Sparsø, Thomas; Schupf, Nicole; Christensen, Kaare; Perls, Thomas T; Newman, Anne B; Werge, Thomas; Snieder, Harold; Spector, Timothy D; Chambers, John C; Koskinen, Seppo; Melbye, Mads; Raitakari, Olli T; Lehtimäki, Terho; Tobin, Martin D; Wain, Louise V; Sinisalo, Juha; Peters, Annette; Meitinger, Thomas; Martin, Nicholas G; Wray, Naomi R; Montgomery, Grant W; Medland, Sarah E; Swertz, Morris A; Vartiainen, Erkki; Borodulin, Katja; Männistö, Satu; Murray, Anna; Bochud, Murielle; Jacquemont, Sébastien; Rivadeneira, Fernando; Hansen, Thomas F; Oldehinkel, Albertine J; Mangino, Massimo; Province, Michael A; Deloukas, Panos; Kooner, Jaspal S; Freathy, Rachel M; Pennell, Craig; Feenstra, Bjarke; Strachan, David P; Lettre, Guillaume; Hirschhorn, Joel; Cusi, Daniele; Heid, Iris M; Hayward, Caroline; Männik, Katrin; Beckmann, Jacques S; Loos, Ruth J F; Nyholt, Dale R; Metspalu, Andres; Eriksson, Johan G; Weedon, Michael N; Salomaa, Veikko; Franke, Lude; Reymond, Alexandre; Frayling, Timothy M; Kutalik, Zoltán

2017-09-29

There are few examples of robust associations between rare copy number variants (CNVs) and complex continuous human traits. Here we present a large-scale CNV association meta-analysis on anthropometric traits in up to 191,161 adult samples from 26 cohorts. The study reveals five CNV associations at 1q21.1, 3q29, 7q11.23, 11p14.2, and 18q21.32 and confirms two known loci at 16p11.2 and 22q11.21, implicating at least one anthropometric trait. The discovered CNVs are recurrent and rare (0.01-0.2%), with large effects on height (>2.4 cm), weight (>5 kg), and body mass index (BMI) (>3.5 kg/m 2 ). Burden analysis shows a 0.41 cm decrease in height, a 0.003 increase in waist-to-hip ratio and increase in BMI by 0.14 kg/m 2 for each Mb of total deletion burden (P = 2.5 × 10 -10 , 6.0 × 10 -5 , and 2.9 × 10 -3 ). Our study provides evidence that the same genes (e.g., MC4R, FIBIN, and FMO5) harbor both common and rare variants affecting body size and that anthropometric traits share genetic loci with developmental and psychiatric disorders.Individual SNPs have small effects on anthropometric traits, yet the impact of CNVs has remained largely unknown. Here, Kutalik and co-workers perform a large-scale genome-wide meta-analysis of structural variation and find rare CNVs associated with height, weight and BMI with large effect sizes.

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

PubMed

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.

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

PubMed Central

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 (P<0.10). Outcomes and analysis Cumulative pairwise and network meta-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. 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

Tutoring Adolescents in Literacy: A Meta-Analysis

ERIC Educational Resources Information Center

Jun, Seung Won; Ramirez, Gloria; Cumming, Alister

2010-01-01

What does research reveal about tutoring adolescents in literacy? We conducted a meta-analysis, identifying 152 published studies, of which 12 met rigorous inclusion criteria. We analyzed the 12 studies for the effects of tutoring according to the type, focus, and amount of tutoring; the number, age, and language background of students; and the…

A meta-analysis investigating factors underlying attrition rates in infant ERP studies.

PubMed

Stets, Manuela; Stahl, Daniel; Reid, Vincent M

2012-01-01

In this meta-analysis, we examined interrelationships between characteristics of infant event-related potential (ERP) studies and their attrition rates. One-hundred and forty-nine published studies provided information on 314 experimental groups of which 181 provided data on attrition. A random effects meta-analysis revealed a high average attrition rate of 49.2%. Additionally, we used meta-regression for 178 groups with attrition data to analyze which variables best explained attrition variance. Our main findings were that the nature of the stimuli-visual, auditory, or combined as well as if stimuli were animated-influenced exclusion rates from the final analysis and that infant age did not alter attrition rates.

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

PubMed

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.

The school environment and student health: a systematic review and meta-ethnography of qualitative research

PubMed Central

2013-01-01

Background There is increasing interest in promoting young people’s health by modifying the school environment. However, existing research offers little guidance on how the school context enables or constrains students’ health behaviours, or how students’ backgrounds relate to these processes. For these reasons, this paper reports on a meta-ethnography of qualitative studies examining: through what processes does the school environment (social and physical) influence young people’s health? Methods Systematic review of qualitative studies. Sixteen databases were searched, eliciting 62, 329 references which were screened, with included studies quality assessed, data extracted and synthesized using an adaptation of Noblit and Hare’s meta-ethnographic approach. Results Nineteen qualitative studies were synthesised to explore processes through which school-level influences on young people’s health might occur. Four over-arching meta-themes emerged across studies focused on a range of different health issues. First, aggressive behaviour and substance use are often a strong source of status and bonding at schools where students feel educationally marginalised or unsafe. Second, health-risk behaviours are concentrated in unsupervised ‘hotspots’ at the school. Third, positive relationships with teachers appear to be critical in promoting student wellbeing and limiting risk behaviour; however, certain aspects of schools’ organisation and education policies constrain this, increasing the likelihood that students look for a sense of identity and social support via health-risk behaviours. Fourth, unhappiness at school can cause students to seek sources of ‘escape’, either by leaving school at lunchtime or for longer unauthorized spells or through substance use. These meta-themes resonate with Markham and Aveyard’s theory of human functioning and school organisation, and we draw on these qualitative data to refine and extend this theory, in particular

The school environment and student health: a systematic review and meta-ethnography of qualitative research.

PubMed

Jamal, Farah; Fletcher, Adam; Harden, Angela; Wells, Helene; Thomas, James; Bonell, Chris

2013-09-03

There is increasing interest in promoting young people's health by modifying the school environment. However, existing research offers little guidance on how the school context enables or constrains students' health behaviours, or how students' backgrounds relate to these processes. For these reasons, this paper reports on a meta-ethnography of qualitative studies examining: through what processes does the school environment (social and physical) influence young people's health? Systematic review of qualitative studies. Sixteen databases were searched, eliciting 62,329 references which were screened, with included studies quality assessed, data extracted and synthesized using an adaptation of Noblit and Hare's meta-ethnographic approach. Nineteen qualitative studies were synthesised to explore processes through which school-level influences on young people's health might occur. Four over-arching meta-themes emerged across studies focused on a range of different health issues. First, aggressive behaviour and substance use are often a strong source of status and bonding at schools where students feel educationally marginalised or unsafe. Second, health-risk behaviours are concentrated in unsupervised 'hotspots' at the school. Third, positive relationships with teachers appear to be critical in promoting student wellbeing and limiting risk behaviour; however, certain aspects of schools' organisation and education policies constrain this, increasing the likelihood that students look for a sense of identity and social support via health-risk behaviours. Fourth, unhappiness at school can cause students to seek sources of 'escape', either by leaving school at lunchtime or for longer unauthorized spells or through substance use. These meta-themes resonate with Markham and Aveyard's theory of human functioning and school organisation, and we draw on these qualitative data to refine and extend this theory, in particular conceptualising more fully the role of young people

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

PubMed

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 (P<0.10). Cumulative pairwise and network meta-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

Effectiveness of Telemedicine for Controlling Asthma Symptoms: A Systematic Review and Meta-analysis.

PubMed

Zhao, Jie; Zhai, Yun-Kai; Zhu, Wei-Jun; Sun, Dong-Xu

2015-06-01

The effectiveness of telemedicine for the management of chronic diseases is unclear. This study examined the effectiveness of telemedicine in relieving asthma symptoms. A systematic review of the Medline, Cochrane, EMBASE, and Google Scholar databases was conducted until December 31, 2013 using the following key words: "asthma," "telemedicine," "telehealth," "e-health," "mobile health," "Internet," "telecommunication," "telemanagement," "remote," and "short message service." Inclusion criteria were randomized controlled trial, a diagnosis of asthma, the majority of the patients were ≥18 years of age, and intervention involved any format of telemedicine. A meta-analysis of eligible studies was conducted with the primary outcome being change of asthma symptoms. Of 813 articles identified, 11 were included in the qualitative synthesis, and 6 were included in the meta-analysis. Among the 11 studies, there were 1,460 patients in the intervention groups and 1,349 in the control groups, and the total numbers of participants ranged from 12 to 481 in the intervention groups and from 12 to 487 in the control groups. The mean age of patients ranged in the intervention groups from 34.4 to 54.6 years and in the control groups from 30.7 to 56.4 years. The treatment duration ranged from 0.5 to 12 months. The meta-analysis of six eligible studies revealed no significant difference in asthma symptom score change between the telemedicine and control groups (pooled Hedges's g=0.34, 95% confidence interval=-0.05 to 0.74, Z=1.69, p=0.090). Telemedicine interventions do not appear to improve asthma function scores, but other benefits may be present.

Quality of Life and Aesthetic Plastic Surgery: A Systematic Review and Meta-analysis.

PubMed

Dreher, Rodrigo; Blaya, Carolina; Tenório, Juliana L C; Saltz, Renato; Ely, Pedro B; Ferrão, Ygor A

2016-09-01

Quality of life (QoL) is an important outcome in plastic surgery. However, authors use different scales to address this subject, making it difficult to compare the outcomes. To address this discrepancy, the aim of this study was to perform a systematic review and a random effect meta-analysis. The search was made in two electronic databases (LILACS and PUBMED) using Mesh and non-Mesh terms related to aesthetic plastic surgery and QoL. We performed qualitative and quantitative analyses of the gathered data. We calculated a random effect meta-analysis with Der Simonian and Laird as variance estimator to compare pre- and postoperative QoL standardized mean difference. To check if there is difference between aesthetic surgeries, we compared reduction mammoplasty to other aesthetic surgeries. Of 1,715 identified, 20 studies were included in the qualitative analysis and 16 went through quantitative analysis. The random effect of all aesthetic surgeries shows that QoL improved after surgery. Reduction mammoplasty has improved QoL more than other procedures in social functioning and physical functioning domains. Aesthetic plastic surgery increases QoL. Reduction mammoplasty seems to have better improvement compared with other aesthetic surgeries.

Disclosure of domestic violence in mental health settings: A qualitative meta-synthesis

PubMed Central

Trevillion, Kylee; Hughes, Bryony; Feder, Gene; Borschmann, Rohan; Oram, Siân

2014-01-01

Little is known about how psychiatric services respond to service users’ experiences of domestic violence. This qualitative meta-synthesis examined the healthcare experiences and expectations of mental health service users experiencing domestic violence. Twenty-two biomedical, social science, grey literature databases and websites were searched, supplemented by citation tracking and expert recommendations. Qualitative studies which included mental health service users (aged ≥ 16 years) with experiences of domestic violence were eligible for inclusion. Two reviewers independently extracted data from included papers and assessed quality. Findings from primary studies were combined using meta-synthesis techniques. Twelve studies provided data on 140 female and four male mental health service users. Themes were generally consistent across studies. Overarching theoretical constructs included the role of professionals in identifying domestic violence and facilitating disclosures, implementing personalized care and referring appropriately. Mental health services often failed to identify and facilitate disclosures of domestic violence, and to develop responses that prioritized service users’ safety. Mental health services were reported to give little consideration to the role of domestic violence in precipitating or exacerbating mental illness and the dominance of the biomedical model and stigma of mental illness were found to inhibit effective responses. Mental health services often fail to adequately address the violence experienced by mental health service users. This meta-synthesis highlights the need for mental health services to establish appropriate strategies and responses to domestic violence to ensure optimal care of this vulnerable population. PMID:25137109

Effect of rhythmic auditory cueing on gait in cerebral palsy: a systematic review and meta-analysis.

PubMed

Ghai, Shashank; Ghai, Ishan; Effenberg, Alfred O

2018-01-01

Auditory entrainment can influence gait performance in movement disorders. The entrainment can incite neurophysiological and musculoskeletal changes to enhance motor execution. However, a consensus as to its effects based on gait in people with cerebral palsy is still warranted. A systematic review and meta-analysis were carried out to analyze the effects of rhythmic auditory cueing on spatiotemporal and kinematic parameters of gait in people with cerebral palsy. Systematic identification of published literature was performed adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses and American Academy for Cerebral Palsy and Developmental Medicine guidelines, from inception until July 2017, on online databases: Web of Science, PEDro, EBSCO, Medline, Cochrane, Embase and ProQuest. Kinematic and spatiotemporal gait parameters were evaluated in a meta-analysis across studies. Of 547 records, nine studies involving 227 participants (108 children/119 adults) met our inclusion criteria. The qualitative review suggested beneficial effects of rhythmic auditory cueing on gait performance among all included studies. The meta-analysis revealed beneficial effects of rhythmic auditory cueing on gait dynamic index (Hedge's g =0.9), gait velocity (1.1), cadence (0.3), and stride length (0.5). This review for the first time suggests a converging evidence toward application of rhythmic auditory cueing to enhance gait performance and stability in people with cerebral palsy. This article details underlying neurophysiological mechanisms and use of cueing as an efficient home-based intervention. It bridges gaps in the literature, and suggests translational approaches on how rhythmic auditory cueing can be incorporated in rehabilitation approaches to enhance gait performance in people with cerebral palsy.

MetaMeta: integrating metagenome analysis tools to improve taxonomic profiling.

PubMed

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 .

Promoting influenza vaccination: insights from a qualitative meta-analysis of 14 years of influenza-related communications research by U.S. Centers for Disease Control and Prevention (CDC).

PubMed

Nowak, Glen J; Sheedy, Kristine; Bursey, Kelli; Smith, Teresa M; Basket, Michelle

2015-06-04

A primary mission of the U.S. Centers for Disease Control and Prevention's (CDC) is promoting immunization against seasonal influenza. As with most education efforts, CDC's influenza-related communications are often informed by formative research. A qualitative meta-analysis of 29 unpublished, primarily qualitative CDC-sponsored studies related to flu and flu vaccination knowledge, attitudes and beliefs (KABs). The studies, undertaken between 2000 and 2013, involved focus groups, in-depth interviews, message testing and surveys. Some involved health care professionals, while others involved members of the public, including sub-populations at risk for severe illness. The themes that emerged suggested progress in terms of KABs related to influenza and influenza vaccination, but also the persistence of many barriers to vaccine acceptance. With respect to the public, recurring themes included limited understanding of influenza and immunization recommendations, indications of greater sub-group recognition of the value of flu vaccination, continued resistance to vaccination among many, and overestimation of the effectiveness of non-vaccine measures. Seven cognitive facilitators of vaccination were identified in the studies along with six cognitive barriers. For health care providers, the analysis suggests greater knowledge and more favorable beliefs, but many misperceptions persist and are similar to those held by the public. KABs often differed by type or category of health care provider. The themes identified in this qualitative analysis illustrate the difficulty in changing KABs related to influenza and influenza vaccine, particularly on the scope and scale needed to greatly improve uptake. Even with an influenza pandemic and more vaccine options available, public and some health care provider perceptions and beliefs are difficult and slow to change. This meta-analysis does, however, provide important insights from previously unpublished information that can help

Human papillomavirus vaccine and demyelinating diseases-A systematic review and meta-analysis.

PubMed

Mouchet, Julie; Salvo, Francesco; Raschi, Emanuel; Poluzzi, Elisabetta; Antonazzo, Ippazio Cosimo; De Ponti, Fabrizio; Bégaud, Bernard

2018-06-01

Approved in 2006, human papillomavirus (HPV) vaccines were initially targeted for girls aged 9-14 years. Although the safety of these vaccines has been monitored through post-licensure surveillance programmes, cases of neurological events have been reported worldwide. The present study aimed to assess the risk of developing demyelination after HPV immunization by meta-analysing risk estimates from pharmacoepidemiologic studies. A systematic review was conducted in Medline, Embase, ISI Web of Science and the Cochrane Library from inception to 10 May 2017, without language restriction. Only observational studies including a control group were retained. Study selection was performed by two independent reviewers with disagreements solved through discussion. This meta-analysis was performed using a generic inverse variance random-effect model. Outcomes of interest included a broad category of central demyelination, multiple sclerosis (MS), optic neuritis (ON), and Guillain-Barré syndrome (GBS), each being considered independently. Heterogeneity was investigated; sensitivity and subgroup analyses were performed when necessary. In parallel, post-licensure safety studies were considered for a qualitative review. This study followed the PRISMA statement and the MOOSE reporting guideline. Of the 2,863 references identified, 11 articles were selected for meta-analysis. No significant association emerged between HPV vaccination and central demyelination, the pooled odds ratio being 0.96 [95% CI 0.77-1.20], with a moderate but non-significant heterogeneity (I 2  = 29%). Similar results were found for MS and ON. Sensitivity analyses did not alter our conclusions. Findings from qualitative review of 14 safety studies concluded in an absence of a relevant signal. Owing to limited data on GBS, no meta-analysis was performed for this outcome. This study strongly supports the absence of association between HPV vaccines and central demyelination. Copyright © 2018 Elsevier Ltd

Mandated reporters' experiences with reporting child maltreatment: a meta-synthesis of qualitative studies.

PubMed

McTavish, Jill R; Kimber, Melissa; Devries, Karen; Colombini, Manuela; MacGregor, Jennifer C D; Wathen, C Nadine; Agarwal, Arnav; MacMillan, Harriet L

2017-10-16

To systematically search for research about the effectiveness of mandatory reporting of child maltreatment and to synthesise qualitative research that explores mandated reporters' (MRs) experiences with reporting. As no studies assessing the effectiveness of mandatory reporting were retrieved from our systematic search, we conducted a meta-synthesis of retrieved qualitative research. Searches in Medline (Ovid), Embase, PsycINFO, Cumulative Index to Nursing and Allied Health Literature, Sociological Abstracts, Education Resources Information Center, Criminal Justice Abstracts and Cochrane Library yielded over 6000 citations, which were deduplicated and then screened by two independent reviewers. English-language, primary qualitative studies that investigated MRs' experiences with reporting of child maltreatment were included. Critical appraisal involved a modified checklist from the Critical Appraisal Skills Programme and qualitative meta-synthesis was used to combine results from the primary studies. All healthcare and social-service settings implicated by mandatory reporting laws were included. Included studies crossed nine high-income countries (USA, Australia, Sweden, Taiwan, Canada, Norway, Finland, Israel and Cyprus) and three middle-income countries (South Africa, Brazil and El Salvador). The studies represent the views of 1088 MRs. Factors that influence MRs' decision to report and MRs' views towards and experiences with mandatory reporting of child maltreatment. Forty-four articles reporting 42 studies were included. Findings indicate that MRs struggle to identify and respond to less overt forms of child maltreatment. While some articles (14%) described positive experiences MRs had with the reporting process, negative experiences were reported in 73% of articles and included accounts of harm to therapeutic relationships and child death following removal from their family of origin. The findings of this meta-synthesis suggest that there are many potentially

A refined method for multivariate meta-analysis and meta-regression

PubMed Central

Jackson, Daniel; Riley, Richard D

2014-01-01

Making inferences about the average treatment effect using the random effects model for meta-analysis is problematic in the common situation where there is a small number of studies. This is because estimates of the between-study variance are not precise enough to accurately apply the conventional methods for testing and deriving a confidence interval for the average effect. We have found that a refined method for univariate meta-analysis, which applies a scaling factor to the estimated effects’ standard error, provides more accurate inference. We explain how to extend this method to the multivariate scenario and show that our proposal for refined multivariate meta-analysis and meta-regression can provide more accurate inferences than the more conventional approach. We explain how our proposed approach can be implemented using standard output from multivariate meta-analysis software packages and apply our methodology to two real examples. © 2013 The Authors. Statistics in Medicine published by John Wiley & Sons, Ltd. PMID:23996351

A refined method for multivariate meta-analysis and meta-regression.

PubMed

Jackson, Daniel; Riley, Richard D

2014-02-20

Making inferences about the average treatment effect using the random effects model for meta-analysis is problematic in the common situation where there is a small number of studies. This is because estimates of the between-study variance are not precise enough to accurately apply the conventional methods for testing and deriving a confidence interval for the average effect. We have found that a refined method for univariate meta-analysis, which applies a scaling factor to the estimated effects' standard error, provides more accurate inference. We explain how to extend this method to the multivariate scenario and show that our proposal for refined multivariate meta-analysis and meta-regression can provide more accurate inferences than the more conventional approach. We explain how our proposed approach can be implemented using standard output from multivariate meta-analysis software packages and apply our methodology to two real examples. Copyright © 2013 John Wiley & Sons, Ltd.

Reproductive disorders among cosmetologists and hairdressers: a meta-analysis.

PubMed

Kim, Dohyung; Kang, Mo-Yeol; Choi, Sungyeul; Park, Jaechan; Lee, Hye-Ji; Kim, Eun-A

2016-07-01

Occupational risks for reproductive disorders among hairdressers and cosmetologists have been examined in numerous epidemiological studies, although the results of those studies have been inconsistent. Therefore, we conducted a meta-analysis of published studies to evaluate the risks of reproductive disorders among cosmetologists and hairdressers. We searched the MEDLINE, EMBASE, and Cochrane Library databases, as well as the reference lists of relevant publications, to identify studies for our analysis. After careful consideration, 19 eligible studies were included in the meta-analysis. We also performed systematic evaluations of publication bias, heterogeneity, and publication quality. Study-specific odds ratios (ORs) were weighted using the inverse of their variance to calculate fixed- and random-effect pooled estimates. The meta-analysis revealed a significantly increased risk of infertility (OR 1.15, 95 % CI 1.03-1.28), fetal death (OR 1.14, 95 % CI 1.04-1.24), and preterm delivery (OR 1.04, 95 % CI 1.00-1.07) among hairdressers and cosmetologists. These findings indicate that hairdressers and cosmetologists have a higher risk of reproductive disorders, compared to the general population.

Randomized controlled trials and meta-analysis in medical education: what role do they play?

PubMed

Cook, David A

2012-01-01

Education researchers seek to understand what works, for whom, in what circumstances. Unfortunately, educational environments are complex and research itself is highly context dependent. Faced with these challenges, some have argued that qualitative methods should supplant quantitative methods such as randomized controlled trials (RCTs) and meta-analysis. I disagree. Good qualitative and mixed-methods research are complementary to, rather than exclusive of, quantitative methods. The complexity and challenges we face should not beguile us into ignoring methods that provide strong evidence. What, then, is the proper role for RCTs and meta-analysis in medical education? First, the choice of study design depends on the research question. RCTs and meta-analysis are appropriate for many, but not all, study goals. They have compelling strengths but also numerous limitations. Second, strong methods will not compensate for a pointless question. RCTs do not advance the science when they make confounded comparisons, or make comparison with no intervention. Third, clinical medicine now faces many of the same challenges we encounter in education. We can learn much from other fields about how to handle complexity in RCTs. Finally, no single study will definitively answer any research question. We need carefully planned, theory-building, programmatic research, reflecting a variety of paradigms and approaches, as we accumulate evidence to change the art and science of education.

Hand hygiene among healthcare workers: A qualitative meta summary using the GRADE-CERQual process

PubMed Central

Chatfield, Sheryl L.; DeBois, Kristen; Nolan, Rachael; Crawford, Hannah; Hallam, Jeffrey S.

2016-01-01

Background: Hand hygiene is considered an effective and potentially modifiable infection control behaviour among healthcare workers (HCW). Several meta-studies have been published that compare quantitatively expressed findings, but limited efforts have been made to synthesise qualitative research. Objectives: This paper provides the first report of integrated findings from qualitative research reports on hand hygiene compliance among HCW worldwide that employs the GRADE-CERQual process of quality assessment. Methods: We conducted database searches and identified 36 reports in which authors conducted qualitative or mixed methods research on hand hygiene compliance among HCW. We used Dedoose analysis software to facilitate extraction of relevant excerpts. We applied the GRADE-CERQual process to describe relative confidence as high, moderate or low for nine aggregate findings. Findings: Highest confidence findings included that HCW believe they have access to adequate training, and that management and resource support are sometimes lacking. Individual, subjective criteria also influence hand hygiene. Discussion: These results suggest the need for further investigation into healthcare cultures that are perceived as supportive for infection control. Surveillance processes have potential, especially if information is perceived by HCW as timely and relevant. PMID:28989515

Basal cortisol levels and metabolic syndrome: A systematic review and meta-analysis of observational studies.

PubMed

Garcez, Anderson; Leite, Heloísa Marquardt; Weiderpass, Elisabete; Paniz, Vera Maria Vieira; Watte, Guilherme; Canuto, Raquel; Olinto, Maria Teresa Anselmo

2018-05-17

To perform a qualitative synthesis (systematic review) and quantitative analysis (meta-analysis) to summarize the evidence regarding the relationship between basal cortisol levels and metabolic syndrome (MetS) in adults. A systematic search was performed in the PubMed, Embase, and PsycINFO databases for observational studies on the association between basal cortisol levels and MetS. The quality of individual studies was assessed by the Newcastle-Ottawa score. A random effects model was used to report pooled quantitative results and the I 2 statistic was used to assess heterogeneity. Egger's and Begg's tests were used to evaluate publication bias. Twenty-six studies (19 cross-sectional and seven case-control) met the inclusion criteria for the systematic review. The majority was classified as having a low risk of bias and used established criteria for the diagnosis of MetS. Twenty-one studies provided data on basal cortisol levels as continuous values and were included in the meta-analysis; they comprised 35 analyses and 11,808 subjects. Pooled results showed no significant difference in basal cortisol levels between subjects with and without MetS (standardized mean difference [SMD] = 0.02, 95% confidence interval [CI]=-0.11 to 0.14). There was high heterogeneity between the studies when all comparisons were considered (I 2  = 83.1%;p < 0.001). Paradoxically, meta-analysis of studies evaluating saliva samples showed no significantly lower basal cortisol levels among subjects with MetS (SMD=-0.18, 95% CI=-0.37 to 0.01), whereas those studies that evaluated serum samples (SMD = 0.11, 95% CI=-0.02 to 0.24) and urine samples (SMD = 0.73, 95% CI=-0.40 to 1.86) showed no significantly higher basal cortisol levels among subjects with MetS. In the subgroup and meta-regression analyses, a significant difference in basal cortisol levels was observed according to study design, population base, age, gender, cortisol level assessment method, and study quality

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

PubMed

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.

Coffee consumption and risk of fractures: a meta-analysis

PubMed Central

Liu, Huifang; Yao, Ke; Zhang, Wenjie; Zhou, Jun; Wu, Taixiang

2012-01-01

Introduction Recent studies have indicated higher risk of fractures among coffee drinkers. To quantitatively assess the association between coffee consumption and the risk of fractures, we conducted this meta-analysis. Material and methods We searched MEDLINE and EMBASE for prospective studies reporting the risk of fractures with coffee consumption. Quality of included studies was assessed with the Newcastle Ottawa scale. We conducted a meta-analysis and a cumulative meta-analysis of relative risk (RR) for an increment of one cup of coffee per day, and explored the potential dose-response relationship. Sensitivity analysis was performed where statistical heterogeneity existed. Results We included 10 prospective studies covering 214,059 participants and 9,597 cases. There was overall 3.5% higher fracture risk for an increment of one cup of coffee per day (RR = 1.035, 95% CI: 1.019-1.052). Pooled RRs were 1.049 (95% CI: 1.022-1.077) for women and 0.910 (95% CI: 0.873-0.949) for men. Among women, RR was 1.055 (95% CI: 0.999-1.114) for younger participants, and 1.047 (95% CI: 1.016-1.080) for older ones. Cumulative meta-analysis indicated that risk estimates reached a stabilization level (RR = 1.035, 95% CI: 1.019-1.052), and it revealed a positive dose-response relationship between coffee consumption and risk of fractures either for men and women combined or women specifically. Conclusions This meta-analysis suggests an overall harm of coffee intake in increasing the risk of fractures, especially for women. But current data are insufficient to reach a convincing conclusion and further research needs to be conducted. PMID:23185185

The meta-analytic big bang.

PubMed

Shadish, William R; Lecy, Jesse D

2015-09-01

This article looks at the impact of meta-analysis and then explores why meta-analysis was developed at the time and by the scholars it did in the social sciences in the 1970s. For the first problem, impact, it examines the impact of meta-analysis using citation network analysis. The impact is seen in the sciences, arts and humanities, and on such contemporaneous developments as multilevel modeling, medical statistics, qualitative methods, program evaluation, and single-case design. Using a constrained snowball sample of citations, we highlight key articles that are either most highly cited or most central to the systematic review network. Then, the article examines why meta-analysis came to be in the 1970s in the social sciences through the work of Gene Glass, Robert Rosenthal, and Frank Schmidt, each of whom developed similar theories of meta-analysis at about the same time. The article ends by explaining how Simonton's chance configuration theory and Campbell's evolutionary epistemology can illuminate why meta-analysis occurred with these scholars when it did and not in medical sciences. Copyright © 2015 John Wiley & Sons, Ltd.

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

PubMed

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.

Autogenic training: a meta-analysis of clinical outcome studies.

PubMed

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.

Does chocolate reduce blood pressure? A meta-analysis.

PubMed

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 < 0.05. 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 mg to 1000 mg in the active treatment

Association between TYK2 polymorphisms and susceptibility to autoimmune rheumatic diseases: a meta-analysis.

PubMed

Lee, Y H; Bae, S-C

2016-10-01

This study aimed to explore whether TYK2 polymorphisms are associated with susceptibility to autoimmune rheumatic diseases. We conducted a meta-analysis on the association between TYK2 polymorphisms and autoimmune rheumatic diseases. Twelve studies with a total of 16,335 patients and 30,065 controls were included in the meta-analysis. Meta-analysis revealed an association between rheumatic diseases and the 2 allele of the TYK2 rs2304256 (OR = 0.885, 95% CI = 0.802-0.978, p = 0.016). Furthermore, stratification by ethnicity identified a significant association between this polymorphism and rheumatic diseases in Caucasians (OR = 0.822, 95% CI = 0.706-0.889, p = 9.5 × 10(-7)), but not in Asians (OR = 1.127, 95% CI = 0.835-1.522, p = 0.434). Meta-analysis by rheumatic disease type revealed a significant association between the 2 allele of the TYK2 rs2304256 and SLE in Caucasians (OR = 0.737, 95% CI = 0.673-0.808, p < 1.0 × 10(-8)) but not in Asians (OR = 1.211, 95% CI = 0.813-1.804, p = 0.347). Meta-analysis revealed that the rs12720356 polymorphism was associated with susceptibility to rheumatic diseases in Caucasians (OR = 0.812, 95% CI = 0.661-0.997, p = 0.046) but not in Asians. Interestingly, the rs280519 polymorphism was significantly associated with susceptibility to SLE both in Caucasians and Asians. However, no associations were found between the rs12720270, rs280500, rs280523 and rs8108236 polymorphisms and susceptibility to rheumatic diseases. This meta-analysis demonstrates that the TYK2 rs2304256 and rs12720356 polymorphisms are associated with susceptibility to rheumatic diseases, rs2304256 polymorphism is associated with SLE in Caucasians, and rs280519 polymorphism is associated with SLE in Caucasians and Asians. © The Author(s) 2016.

Parenting and Self-Regulation in Preschoolers: A Meta-Analysis

ERIC Educational Resources Information Center

Karreman, Annemiek; van Tuijl, Cathy; van Aken, Marcel A. G.; Dekovic, Maja

2006-01-01

A meta-analysis of 41 studies was conducted to examine the strength of the relation between parenting (positive control, negative control and responsiveness) and self-regulation in preschoolers. Results revealed significant associations between both types of parental control and self-regulation, with effect sizes being small in magnitude. There…

Effects of prefrontal tDCS on executive function: Methodological considerations revealed by meta-analysis.

PubMed

Imburgio, Michael J; Orr, Joseph M

2018-05-01

A meta-analysis of studies using single-session transcranial direct current stimulation (tDCS) to target the dorsolateral prefrontal cortex (DLPFC) was undertaken to examine the effect of stimulation on executive function (EF) in healthy samples. 27 studies were included in analyses, yielding 71 effect sizes. The most relevant measure for each task was determined a priori and used to calculate Hedge's g. Methodological characteristics of each study were examined individually as potential moderators of effect size. Stimulation effects on three domains of EF (inhibition of prepotent responses, mental set shifting, and information updating and monitoring) were analyzed separately. In line with previous work, the current study found no significant effect of anodal unilateral tDCS, cathodal unilateral tDCS, or bilateral tDCS on EF. Further moderator and subgroup analyses were only carried out for anodal unilateral montages due to the small number of studies using other montages. Subgroup analyses revealed a significant effect of anodal unilateral tDCS on updating tasks, but not on inhibition or set-shifting tasks. Cathode location significantly moderated the effect of anodal unilateral tDCS. Extracranial cathodes yielded a significant effect on EF while cranial cathodes yielded no effect. Anode size also significantly moderated effect of anodal unilateral tDCS, with smaller anodes being more effective than larger anodes. In summary, anodal DLPFC stimulation is more effective at improving updating ability than inhibition and set-shifting ability, but anodal stimulation can significantly improve general executive function when extracranial cathodes or small anodes are used. Future meta-analyses may examine how stimulation's effects on specific behavioral tasks, rather than broader domains, might be affected by methodological moderators. Copyright © 2018 Elsevier Ltd. All rights reserved.

A Meta-Summary of Qualitative Findings about Professional Services for Survivors of Sexual Violence

ERIC Educational Resources Information Center

Martsolf, Donna S.; Draucker, Claire B.; Cook, Christina B.; Ross, Ratchneewan; Stidham, Andrea Warner; Mweemba, Prudencia

2010-01-01

Sexual violence occurs at alarming rates in children and adults. Survivors experience myriad negative health outcomes and legal problems, which place them in need of professional services. A meta-summary was conducted of 31 published qualitative studies on adults' responses to sexual violence, with a focus on survivors' use of professional…

Local anesthetics injection therapy for musculoskeletal disorders: a systematic review and meta-analysis.

PubMed

Mosshammer, Dirk; Mayer, Benjamin; Joos, Stefanie

2013-06-01

Therapeutic injections with local anesthetics (TLA) are widespread and are used for various symptoms of the musculoskeletal system. The aim of the present project was to evaluate the efficacy and safety of TLA in the treatment of musculoskeletal disorders. Systematic literature search for controlled clinical trials (Medline, Cochrane, CAMbase, hand search of references) without language limitation; independent screening of the search results (n=3200 hits), abstract reading, and full-text analysis by 2 reviewers. Two authors independently extracted the data and assessed study quality. Meta-analysis was calculated for studies using a continuous scale for pain assessment. Twenty-four controlled trials were included in this review. In almost all studies no primary outcome measure was defined and the overall study quality was low. The qualitative data analysis revealed no clear trend for or against TLA. The meta-analysis of 12 studies showed no significant difference in pain reduction for TLA compared with control treatments consisting of saline injections or other substances, oral analgesics, or nonpharmacological interventions (standardized mean difference -0.31, 95% confidence interval, -0.75 to 0.14). Minor adverse side effects were reported in 7 studies in both the TLA and the control groups with no trend for one of the groups to be safer. Despite the widespread use of TLA for musculoskeletal disorders in daily practice, available data are sparse and of low quality and, therefore, do not allow a final recommendation. High-quality studies are needed to close the gap between common practice and research.

An overview of meta-analysis for clinicians.

PubMed

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.

Improvement of endothelial function by pitavastatin: a meta-analysis.

PubMed

Katsiki, Niki; Reiner, Željko; Tedeschi Reiner, Eugenia; Al-Rasadi, Khalid; Pirro, Matteo; Mikhailidis, Dimitri P; Sahebkar, Amirhossein

2018-02-01

Dyslipidemia is commonly associated with endothelial dysfunction and increased cardiovascular risk. Pitavastatin has been shown to reduce total and low-density lipoprotein cholesterol, to increase high-density lipoprotein (HDL)-cholesterol and improve HDL function. Furthermore, several trials explored its effects on flow-mediated dilation (FMD), as an index of endothelial function. The authors evaluated the effect of pitavastatin therapy on FMD. The authors performed a systematic review and meta-analysis of all clinical trials exploring the impact of pitavastatin on FMD. The search included PubMed-Medline, Scopus, ISI Web of Knowledge and Google Scholar databases. Quantitative data synthesis was performed using a random-effects model, with weighted mean difference (WMD) and 95% confidence interval (CI) as summary statistics. Six eligible studies comprising 7 treatment arms were selected for this meta-analysis. Overall, WMD was significant for the effect of pitavastatin on FMD (2.45%, 95% CI: 1.31, 3.60, p < 0.001) and the effect size was robust in the leave-one-out sensitivity analysis. This meta-analysis of all available clinical trials revealed a significant increase of FMD induced by pitavastatin.

Cumulative meta-analysis: a new tool for detection of temporal trends and publication bias in ecology.

PubMed Central

Leimu, Roosa; Koricheva, Julia

2004-01-01

Temporal changes in the magnitude of research findings have recently been recognized as a general phenomenon in ecology, and have been attributed to the delayed publication of non-significant results and disconfirming evidence. Here we introduce a method of cumulative meta-analysis which allows detection of both temporal trends and publication bias in the ecological literature. To illustrate the application of the method, we used two datasets from recently conducted meta-analyses of studies testing two plant defence theories. Our results revealed three phases in the evolution of the treatment effects. Early studies strongly supported the hypothesis tested, but the magnitude of the effect decreased considerably in later studies. In the latest studies, a trend towards an increase in effect size was observed. In one of the datasets, a cumulative meta-analysis revealed publication bias against studies reporting disconfirming evidence; such studies were published in journals with a lower impact factor compared to studies with results supporting the hypothesis tested. Correlation analysis revealed neither temporal trends nor evidence of publication bias in the datasets analysed. We thus suggest that cumulative meta-analysis should be used as a visual aid to detect temporal trends and publication bias in research findings in ecology in addition to the correlative approach. PMID:15347521

Identifying fundamental criteria for eating disorder recovery: a systematic review and qualitative meta-analysis.

PubMed

de Vos, Jan Alexander; LaMarre, Andrea; Radstaak, Mirjam; Bijkerk, Charlotte Ariane; Bohlmeijer, Ernst T; Westerhof, Gerben J

2017-01-01

Outcome studies for eating disorders regularly measure pathology change or remission as the only outcome. Researchers, patients and recovered individuals highlight the importance of using additional criteria for measuring eating disorder recovery. There is no clear consensus on which additional criteria are most fundamental. Studies focusing on the perspectives of recovered patients show criteria which are closely related to dimensions of positive functioning as conceptualized in the complete mental health model. The aim of this study was to identify fundamental criteria for eating disorder recovery according to recovered individuals. A systematic review and a qualitative meta-analytic approach were used. Eighteen studies with recovered individuals and meeting various quality criteria were included. The result sections of the included papers were searched for themes that were stated as criteria for recovery or 'being recovered'. All themes were analyzed using a meta-summary technique. Themes were labeled into criteria for recovery and the frequency of the found criteria was examined. In addition to the remission of eating disorder pathology, dimensions of psychological well-being and self-adaptability/resilience were found to be fundamental criteria for eating disorder recovery. The most frequently mentioned criteria were: self-acceptance, positive relationships, personal growth, decrease in eating disorder behavior/cognitions, self-adaptability/resilience and autonomy. People who have recovered rate psychological well-being as a central criterion for ED recovery in addition to the remission of eating disorder symptoms. Supplementary criteria, besides symptom remission, are needed to measure recovery. We recommend including measurements of psychological well-being and self-adaptability/resilience in future research, such as outcome studies and in routine outcome measurement.

Effect of soy isoflavone supplementation on plasma lipoprotein(a) concentrations: A meta-analysis.

PubMed

Simental-Mendía, Luis E; Gotto, Antonio M; Atkin, Stephen L; Banach, Maciej; Pirro, Matteo; Sahebkar, Amirhossein

Soy supplementation has been shown to reduce total and low-density lipoprotein cholesterol, while increasing high-density lipoprotein cholesterol. However, contradictory effects of soy isoflavone supplementation on lipoprotein(a) [Lp(a)] have been reported suggesting the need for a meta-analysis to be undertaken. The aim of the study was to investigate the impact of supplementation with soy isoflavones on plasma Lp(a) levels through a systematic review and meta-analysis of eligible randomized placebo-controlled trials. The search included PubMed-Medline, Scopus, ISI Web of Knowledge, and Google Scholar databases (by March 26, 2017), and quality of studies was evaluated according to Cochrane criteria. Quantitative data synthesis was performed using a random-effects model, with standardized mean difference and 95% confidence interval as summary statistics. Meta-regression and leave-one-out sensitivity analysis were performed to assess the modifiers of treatment response. Ten eligible studies comprising 11 treatment arms with 973 subjects were selected for the meta-analysis. Meta-analysis did not suggest any significant alteration of plasma Lp(a) levels after supplementation with soy isoflavones (standardized mean difference: 0.08, 95% confidence interval: -0.05, 0.20, P = .228). The effect size was robust in the leave-one-out sensitivity analysis. In meta-regression analysis, neither dose nor duration of supplementation with soy isoflavones was significantly associated with the effect size. This meta-analysis of the 10 available randomized placebo-controlled trials revealed no significant effect of soy isoflavones treatment on plasma Lp(a) concentrations. Copyright © 2017 National Lipid Association. Published by Elsevier Inc. All rights reserved.

Religion and Completed Suicide: a Meta-Analysis

PubMed Central

Wu, Andrew; Wang, Jing-Yu; Jia, Cun-Xian

2015-01-01

Introduction Suicide is a major public health concern and a leading cause of death around the world. How religion influences the risk of completed suicide in different settings across the world requires clarification in order to best inform suicide prevention strategies. Methods A meta-analysis using search results from Pubmed and Web of Science databases was conducted following PRISMA protocol and using the keywords “religion” or “religious” or “religiosity” or “spiritual” or “spirituality” plus “suicide” or “suicidality” or “suicide attempt”. Random and fixed effects models were used to generate pooled ORs and I2 values. Sub-analyses were conducted among the following categories: young age (<45yo), older age (≥45yo), western culture, eastern culture, and religious homogeneity. Results Nine studies that altogether evaluated 2339 suicide cases and 5252 comparison participants met all selection criteria and were included in the meta-analysis. The meta-analysis suggested an overall protective effect of religiosity from completed suicide with a pooled OR of 0.38 (95% CI: 0.21–0.71) and I2 of 91%. Sub-analyses similarly revealed significant protective effects for studies performed in western cultures (OR = 0.29, 95% CI: 0.18–0.46), areas with religious homogeneity (OR = 0.18, 95% CI: 0.13–0.26), and among older populations (OR = 0.42, 95% CI: 0.21–0.84). High heterogeneity of our meta-analysis was attributed to three studies in which the methods varied from the other six. Conclusion Religion plays a protective role against suicide in a majority of settings where suicide research is conducted. However, this effect varies based on the cultural and religious context. Therefore, public health professionals need to strongly consider the current social and religious atmosphere of a given population when designing suicide prevention strategies. PMID:26110867

Religion and Completed Suicide: a Meta-Analysis.

PubMed

Wu, Andrew; Wang, Jing-Yu; Jia, Cun-Xian

2015-01-01

Suicide is a major public health concern and a leading cause of death around the world. How religion influences the risk of completed suicide in different settings across the world requires clarification in order to best inform suicide prevention strategies. A meta-analysis using search results from Pubmed and Web of Science databases was conducted following PRISMA protocol and using the keywords "religion" or "religious" or "religiosity" or "spiritual" or "spirituality" plus "suicide" or "suicidality" or "suicide attempt". Random and fixed effects models were used to generate pooled ORs and I2 values. Sub-analyses were conducted among the following categories: young age (<45 yo), older age (≥45 yo), western culture, eastern culture, and religious homogeneity. Nine studies that altogether evaluated 2339 suicide cases and 5252 comparison participants met all selection criteria and were included in the meta-analysis. The meta-analysis suggested an overall protective effect of religiosity from completed suicide with a pooled OR of 0.38 (95% CI: 0.21-0.71) and I2 of 91%. Sub-analyses similarly revealed significant protective effects for studies performed in western cultures (OR = 0.29, 95% CI: 0.18-0.46), areas with religious homogeneity (OR = 0.18, 95% CI: 0.13-0.26), and among older populations (OR = 0.42, 95% CI: 0.21-0.84). High heterogeneity of our meta-analysis was attributed to three studies in which the methods varied from the other six. Religion plays a protective role against suicide in a majority of settings where suicide research is conducted. However, this effect varies based on the cultural and religious context. Therefore, public health professionals need to strongly consider the current social and religious atmosphere of a given population when designing suicide prevention strategies.

Network meta-analysis: an introduction for pharmacists.

PubMed

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.

A User's Guide to the Meta-Analysis of Research Studies. Meta-Stat: Software To Aid in the Meta-Analysis of Research Findings.

ERIC Educational Resources Information Center

Rudner, Lawrence M.; Glass Gene V.; Evartt, David L.; Emery, Patrick J.

This manual and the accompanying software are intended to provide a step-by-step guide to conducting a meta-analytic study along with references for further reading and free high-quality software, "Meta-Stat.""Meta-Stat" is a comprehensive package designed to help in the meta-analysis of research studies in the social and behavioral sciences.…

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

PubMed

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

Multidimensional Perfectionism and Burnout: A Meta-Analysis.

PubMed

Hill, Andrew P; Curran, Thomas

2016-08-01

A meta-analysis of research examining the relationships between multidimensional perfectionism and burnout is provided. In doing so, relationships before and after controlling for the relationship between dimensions of perfectionism were examined along with whether relationships were moderated by domain (work, sport, or education). A literature search yielded 43 studies (N = 9,838) and 663 effect sizes. Meta-analysis using random-effects models revealed that perfectionistic strivings had small negative or non-significant relationships with overall burnout and symptoms of burnout. By contrast, perfectionistic concerns displayed medium-to-large and medium positive relationships with overall burnout and symptoms of burnout. After controlling for the relationship between dimensions of perfectionism, "pure" perfectionistic strivings displayed notably larger negative relationships. In terms of moderation, in some cases, perfectionistic strivings were less adaptive and perfectionistic concerns more maladaptive in the work domain. Future research should examine explanatory mechanisms, adopt longitudinal designs, and develop interventions to reduce perfectionistic concerns fueled burnout. © 2015 by the Society for Personality and Social Psychology, Inc.

Infant search and object permanence: a meta-analysis of the A-not-B error.

PubMed

Wellman, H M; Cross, D; Bartsch, K

1987-01-01

Research on Piaget's stage 4 object concept has failed to reveal a clear or consistent pattern of results. Piaget found that 8-12-month-old infants would make perserverative errors; his explanation for this phenomenon was that the infant's concept of the object was contextually dependent on his or her actions. Some studies designed to test Piaget's explanation have replicated Piaget's basic finding, yet many have found no preference for the A location or the B location or an actual preference for the B location. More recently, researchers have attempted to uncover the causes for these results concerning the A-not-B error. Again, however, different studies have yielded different results, and qualitative reviews have failed to yield a consistent explanation for the results of the individual studies. This state of affairs suggests that the phenomenon may simply be too complex to be captured by individual studies varying 1 factor at a time and by reviews based on similar qualitative considerations. Therefore, the current investigation undertook a meta-analysis, a synthesis capturing the quantitative information across the now sizable number of studies. We entered several important factors into the meta-analysis, including the effects of age, the number of A trials, the length of delay between hiding and search, the number of locations, the distances between locations, and the distinctive visual properties of the hiding arrays. Of these, the analysis consistently indicated that age, delay, and number of hiding locations strongly influence infants' search. The pattern of specific findings also yielded new information about infant search. A general characterization of the results is that, at every age, both above-chance and below-chance performance was observed. That is, at each age at least 1 combination of delay and number of locations yielded above-chance A-not-B errors or significant perseverative search. At the same time, at each age at least 1 alternative

The paradox of intragroup conflict: a meta-analysis.

PubMed

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.

Dating Violence among High-Risk Young Women: A Systematic Review Using Quantitative and Qualitative Methods

PubMed Central

Joly, Lauren E.; Connolly, Jennifer

2016-01-01

Our systematic review identified 21 quantitative articles and eight qualitative articles addressing dating violence among high risk young women. The groups of high-risk young women in this review include street-involved, justice-involved, pregnant or parenting, involved with Child Protective Services, and youth diagnosed with a mental health issue. Our meta-analysis of the quantitative articles indicated that 34% (CI = 0.24–0.45) of high-risk young women report that they have been victims of physical dating violence and 45% (CI = 0.31–0.61) of these young women report perpetrating physical dating violence. Significant moderator variables included questionnaire and timeframe. Meta-synthesis of the qualitative studies revealed that high-risk young women report perpetrating dating violence to gain power and respect, whereas women report becoming victims of dating violence due to increased vulnerability. PMID:26840336

Declining Bias and Gender Wage Discrimination? A Meta-Regression Analysis

ERIC Educational Resources Information Center

Jarrell, Stephen B.; Stanley, T. D.

2004-01-01

The meta-regression analysis reveals that there is a strong tendency for discrimination estimates to fall and wage discrimination exist against the woman. The biasing effect of researchers' gender of not correcting for selection bias has weakened and changes in labor market have made it less important.

[Applications of meta-analysis in multi-omics].

PubMed

Han, Mingfei; Zhu, Yunping

2014-07-01

As a statistical method integrating multi-features and multi-data, meta-analysis was introduced to the field of life science in the 1990s. With the rapid advances in high-throughput technologies, life omics, the core of which are genomics, transcriptomics and proteomics, is becoming the new hot spot of life science. Although the fast output of massive data has promoted the development of omics study, it results in excessive data that are difficult to integrate systematically. In this case, meta-analysis is frequently applied to analyze different types of data and is improved continuously. Here, we first summarize the representative meta-analysis methods systematically, and then study the current applications of meta-analysis in various omics fields, finally we discuss the still-existing problems and the future development of meta-analysis.

Meta-Analysis at Middle Age: A Personal History

ERIC Educational Resources Information Center

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…

Estimating a test's accuracy using tailored meta-analysis-How setting-specific data may aid study selection.

PubMed

Willis, Brian H; Hyde, Christopher J

2014-05-01

To determine a plausible estimate for a test's performance in a specific setting using a new method for selecting studies. It is shown how routine data from practice may be used to define an "applicable region" for studies in receiver operating characteristic space. After qualitative appraisal, studies are selected based on the probability that their study accuracy estimates arose from parameters lying in this applicable region. Three methods for calculating these probabilities are developed and used to tailor the selection of studies for meta-analysis. The Pap test applied to the UK National Health Service (NHS) Cervical Screening Programme provides a case example. The meta-analysis for the Pap test included 68 studies, but at most 17 studies were considered applicable to the NHS. For conventional meta-analysis, the sensitivity and specificity (with 95% confidence intervals) were estimated to be 72.8% (65.8, 78.8) and 75.4% (68.1, 81.5) compared with 50.9% (35.8, 66.0) and 98.0% (95.4, 99.1) from tailored meta-analysis using a binomial method for selection. Thus, for a cervical intraepithelial neoplasia (CIN) 1 prevalence of 2.2%, the post-test probability for CIN 1 would increase from 6.2% to 36.6% between the two methods of meta-analysis. Tailored meta-analysis provides a method for augmenting study selection based on the study's applicability to a setting. As such, the summary estimate is more likely to be plausible for a setting and could improve diagnostic prediction in practice. Copyright © 2014 Elsevier Inc. All rights reserved.

Statistical Power in Meta-Analysis

ERIC Educational Resources Information Center

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…

Diagnostic Accuracy of Memory Measures in Alzheimer’s Dementia and Mild Cognitive Impairment: a Systematic Review and Meta-Analysis

PubMed Central

Weissberger, Gali H.; Strong, Jessica V.; Stefanidis, Kayla B.; Summers, Mathew J.; Bondi, Mark W.; Stricker, Nikki H.

2018-01-01

With an increasing focus on biomarkers in dementia research, illustrating the role of neuropsychological assessment in detecting mild cognitive impairment (MCI) and Alzheimer’s dementia (AD) is important. This systematic review and meta-analysis, conducted in accordance with PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) standards, summarizes the sensitivity and specificity of memory measures in individuals with MCI and AD. Both meta-analytic and qualitative examination of AD versus healthy control (HC) studies (n = 47) revealed generally high sensitivity and specificity (≥ 80% for AD comparisons) for measures of immediate (sensitivity = 87%, specificity = 88%) and delayed memory (sensitivity = 89%, specificity = 89%), especially those involving word-list recall. Examination of MCI versus HC studies (n = 38) revealed generally lower diagnostic accuracy for both immediate (sensitivity = 72%, specificity = 81%) and delayed memory (sensitivity = 75%, specificity = 81%). Measures that differentiated AD from other conditions (n = 10 studies) yielded mixed results, with generally high sensitivity in the context of low or variable specificity. Results confirm that memory measures have high diagnostic accuracy for identification of AD, are promising but require further refinement for identification of MCI, and provide support for ongoing investigation of neuropsychological assessment as a cognitive biomarker of preclinical AD. Emphasizing diagnostic test accuracy statistics over null hypothesis testing in future studies will promote the ongoing use of neuropsychological tests as Alzheimer’s disease research and clinical criteria increasingly rely upon cerebrospinal fluid (CSF) and neuroimaging biomarkers. PMID:28940127

Using beta coefficients to impute missing correlations in meta-analysis research: Reasons for caution.

PubMed

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).

Therapy of bovine endometritis with prostaglandin F2α: a meta-analysis.

PubMed

Haimerl, P; Heuwieser, W; Arlt, S

2013-05-01

The objective of the conducted meta-analysis was to assess the efficacy of the treatment of bovine endometritis with PGF(2α) by statistical means. Postpartum uterine infections have a high prevalence and a very negative effect on reproductive performance in dairy cattle. Because of a wide discordance between research results, a meta-analysis of the efficacy of the treatment of bovine endometritis with PGF(2α) was conducted. A comprehensive literature search was performed using online databases to reveal a total of 2,307 references. In addition, 5 articles were retrieved by reviewing citations. After applying specific exclusion criteria and evaluating specific evidence parameters, 5 publications, comprising 6 trials, were eligible for being analyzed by means of meta-analysis. Data for each trial were extracted and analyzed using meta-analysis software Review Manager (version 5.1; The Nordic Cochrane Centre, Copenhagen, Denmark). Estimated effect sizes of PGF(2α) were calculated on calving to first service and calving to conception interval. Prostaglandin F(2α) treatment of cows with chronic endometritis had a negative effect on both reproductive performance parameters. Heterogeneity was substantial for calving to first service and calving to conception interval [I(2) (measure of variation beyond chance)=100 and 87%, respectively]; therefore, random-effects models were used. Sensitivity analysis as well as subgroup analysis showed that the performance of randomization was influential in modifying effect size of PGF(2α) treatment. The funnel plot illustrated a publication bias toward smaller studies that reported a prolonged calving to conception interval after a PGF(2α) treatment. We conclude that the investigation of this subject by means of meta-analysis did not reveal an improvement of reproductive performance of cows with endometritis after treatment with PGF(2α). Furthermore, there is a shortage of comparable high quality studies investigating

Journal article reporting standards for qualitative primary, qualitative meta-analytic, and mixed methods research in psychology: The APA Publications and Communications Board task force report.

PubMed

Levitt, Heidi M; Bamberg, Michael; Creswell, John W; Frost, David M; Josselson, Ruthellen; Suárez-Orozco, Carola

2018-01-01

The American Psychological Association Publications and Communications Board Working Group on Journal Article Reporting Standards for Qualitative Research (JARS-Qual Working Group) was charged with examining the state of journal article reporting standards as they applied to qualitative research and with generating recommendations for standards that would be appropriate for a wide range of methods within the discipline of psychology. These standards describe what should be included in a research report to enable and facilitate the review process. This publication marks a historical moment-the first inclusion of qualitative research in APA Style, which is the basis of both the Publication Manual of the American Psychological Association (APA, 2010) and APA Style CENTRAL, an online program to support APA Style. In addition to the general JARS-Qual guidelines, the Working Group has developed standards for both qualitative meta-analysis and mixed methods research. The reporting standards were developed for psychological qualitative research but may hold utility for a broad range of social sciences. They honor a range of qualitative traditions, methods, and reporting styles. The Working Group was composed of a group of researchers with backgrounds in varying methods, research topics, and approaches to inquiry. In this article, they present these standards and their rationale, and they detail the ways that the standards differ from the quantitative research reporting standards. They describe how the standards can be used by authors in the process of writing qualitative research for submission as well as by reviewers and editors in the process of reviewing research. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Psychophysiology of Aggression, Psychopathy, and Conduct Problems: A Meta-Analysis

ERIC Educational Resources Information Center

Lorber, Michael F.

2004-01-01

A meta-analysis of 95 studies was conducted to investigate the relations of heart rate (HR) and electrodermal activity (EDA) with aggression, psychopathy, and conduct problems. Analyses revealed a complex constellation of interactive effects, with a failure in some cases of autonomic patterns to generalize across antisocial spectrum behavior…

Association between glutathione S-transferase M1, P1, and NFKB1 polymorphisms and systemic lupus erythematosus susceptibility: a meta-analysis.

PubMed

Lee, Y H; Song, G G

2016-09-30

This study aimed to determine whether Glutathione S-transferase M1 (GSTM1), P1 (GSTT1), NFKB1 polymorphisms confer susceptibility to systemic lupus erythematosus (SLE). We performed a meta-analysis on the associations between GSTM1 and GSTT1 null genotypes, and NFKB1 -94 ins/delATTG polymorphisms and SLE. In total, seven studies were considered for this meta-analysis, which comprised 2,119 SLE patients and 3,014 healthy controls. Meta-analysis of the GSTM1 null polymorphism in 869 SLE and 1,544 control subjects revealed an association between SLE and the GSTM1 null genotype (OR = 1.321, 95% CI = 1.103-1.583, p = 0.002). Stratification by ethnicity indicated an association between the GSTM1 null genotype and SLE in Asians (OR = 1.334, 95% CI = 1.096-1.623, p = 0.004). However, meta-analysis of the GSTT1 null polymorphism, comprising 717 SLE and 1,008 control subjects, revealed no association between SLE and the GSTT1 null genotype overall (OR = 0.850, 95% CI = 0.687-1.051, p = 0.113) or in an Asian population (OR = 0.794, 95% CI = 0.594-1.061, p = 0.119). Meta-analysis of the NFKB1 -94 ins/delATTG polymorphism, comprising 1,250 SLE and 1,127 control subjects, revealed an association between SLE and the NFKB1 D allele (OR = 1.127, 95% CI = 1.011-1.257, p = 0.031). Ethnicity-specific meta-analysis revealed an association between the NFKB1 D allele and SLE in Asians (OR = 1.155, 95% CI = 1.026-1.300, p = 0.017). This meta-analysis demonstrates that the functional GSTM1 and NFKB1 polymorphisms are associated with the SLE risk in Asians.

A meta-analysis and review of holistic face processing.

PubMed

Richler, Jennifer J; Gauthier, Isabel

2014-09-01

The concept of holistic processing is a cornerstone of face recognition research, yet central questions related to holistic processing remain unanswered, and debates have thus far failed to reach a resolution despite accumulating empirical evidence. We argue that a considerable source of confusion in this literature stems from a methodological problem. Specifically, 2 measures of holistic processing based on the composite paradigm (complete design and partial design) are used in the literature, but they often lead to qualitatively different results. First, we present a comprehensive review of the work that directly compares the 2 designs, and which clearly favors the complete design over the partial design. Second, we report a meta-analysis of holistic face processing according to both designs and use this as further evidence for one design over the other. The meta-analysis effect size of holistic processing in the complete design is nearly 3 times that of the partial design. Effect sizes were not correlated between measures, consistent with the suggestion that they do not measure the same thing. Our meta-analysis also examines the correlation between conditions in the complete design of the composite task, and suggests that in an individual differences context, little is gained by including a misaligned baseline. Finally, we offer a comprehensive review of the state of knowledge about holistic processing based on evidence gathered from the measure we favor based on the 1st sections of our review-the complete design-and outline outstanding research questions in that new context. PsycINFO Database Record (c) 2014 APA, all rights reserved.

A Meta-Analysis and Review of Holistic Face Processing

PubMed Central

Richler, Jennifer J.; Gauthier, Isabel

2014-01-01

The concept of holistic processing is a cornerstone of face recognition research, yet central questions related to holistic processing remain unanswered, and debates have thus far failed to reach a resolution despite accumulating empirical evidence. We argue that a considerable source of confusion in this literature stems from a methodological problem. Specifically, two different measures of holistic processing based on the composite paradigm (complete design and partial design) are used in the literature, but they often lead to qualitatively different results. First, we present a comprehensive review of the work that directly compares the two designs, and which clearly favors the complete design over the partial design. Second, we report a meta-analysis of holistic face processing according to both designs, and use this as further evidence for one design over the other. The meta-analysis effect size of holistic processing in the complete design is nearly three times that of the partial design. Effect sizes were not correlated between measures, consistent with the suggestion that they do not measure the same thing. Our meta-analysis also examines the correlation between conditions in the complete design of the composite task, and suggests that in an individual differences context, little is gained by including a misaligned baseline. Finally, we offer a comprehensive review of the state of knowledge about holistic processing based on evidence gathered from the measure we favor based on the first sections of our review—the complete design—and outline outstanding research questions in that new context. PMID:24956123

Formalizing the definition of meta-analysis in Molecular Ecology.

PubMed

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.

Relationship between School Suspension and Student Outcomes: A Meta-Analysis

ERIC Educational Resources Information Center

Noltemeyer, Amity L.; Ward, Rose Marie; Mcloughlin, Caven

2015-01-01

Although the association between school suspension and deleterious outcomes is widely acknowledged, policy and practice need to be informed by an evidence base derived from multiple studies revealing consistent trends. This meta-analysis aims to address this void by examining the degree to which different types of school suspensions (in-school…

Experiences of patient-centredness with specialized community-based care: a systematic review and qualitative meta-synthesis.

PubMed

Winsor, S; Smith, A; Vanstone, M; Giacomini, M; Brundisini, F K; DeJean, D

2013-01-01

Specialized community-based care (SCBC) endeavours to help patients manage chronic diseases by formalizing the link between primary care providers and other community providers with specialized training. Many types of health care providers and community-based programs are employed in SCBC. Patient-centred care focuses on patients' psychosocial experience of health and illness to ensure that patients' care plans are modelled on their individual values, preferences, spirituality, and expressed needs. To synthesize qualitative research on patient and provider experiences of SCBC interventions and health care delivery models, using the core principles of patient-centredness. This report synthesizes 29 primary qualitative studies on the topic of SCBC interventions for patients with chronic conditions. Included studies were published between 2002 and 2012, and followed adult patients in North America, Europe, Australia, and New Zealand. Qualitative meta-synthesis was used to integrate findings across primary research studies. Three core themes emerged from the analysis: patients' health beliefs affect their participation in SCBC interventions;patients' experiences with community-based care differ from their experiences with hospital-based care;patients and providers value the role of nurses differently in community-based chronic disease care. Qualitative research findings are not intended to generalize directly to populations, although meta-synthesis across several qualitative studies builds an increasingly robust understanding that is more likely to be transferable. The diversity of interventions that fall under SCBC and the cross-interventional focus of many of the studies mean that findings might not be generalizable to all forms of SCBC or its specific components. Patients with chronic diseases who participated in SCBC interventions reported greater satisfaction when SCBC helped them better understand their diagnosis, facilitated increased socialization, provided

Diagnostic Accuracy of Memory Measures in Alzheimer's Dementia and Mild Cognitive Impairment: a Systematic Review and Meta-Analysis.

PubMed

Weissberger, Gali H; Strong, Jessica V; Stefanidis, Kayla B; Summers, Mathew J; Bondi, Mark W; Stricker, Nikki H

2017-12-01

With an increasing focus on biomarkers in dementia research, illustrating the role of neuropsychological assessment in detecting mild cognitive impairment (MCI) and Alzheimer's dementia (AD) is important. This systematic review and meta-analysis, conducted in accordance with PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) standards, summarizes the sensitivity and specificity of memory measures in individuals with MCI and AD. Both meta-analytic and qualitative examination of AD versus healthy control (HC) studies (n = 47) revealed generally high sensitivity and specificity (≥ 80% for AD comparisons) for measures of immediate (sensitivity = 87%, specificity = 88%) and delayed memory (sensitivity = 89%, specificity = 89%), especially those involving word-list recall. Examination of MCI versus HC studies (n = 38) revealed generally lower diagnostic accuracy for both immediate (sensitivity = 72%, specificity = 81%) and delayed memory (sensitivity = 75%, specificity = 81%). Measures that differentiated AD from other conditions (n = 10 studies) yielded mixed results, with generally high sensitivity in the context of low or variable specificity. Results confirm that memory measures have high diagnostic accuracy for identification of AD, are promising but require further refinement for identification of MCI, and provide support for ongoing investigation of neuropsychological assessment as a cognitive biomarker of preclinical AD. Emphasizing diagnostic test accuracy statistics over null hypothesis testing in future studies will promote the ongoing use of neuropsychological tests as Alzheimer's disease research and clinical criteria increasingly rely upon cerebrospinal fluid (CSF) and neuroimaging biomarkers.

Association between foot type and lower extremity injuries: systematic literature review with meta-analysis.

PubMed

Tong, Jasper W K; Kong, Pui W

2013-10-01

Systematic literature review with meta-analysis. To investigate the association between nonneutral foot types (high arch and flatfoot) and lower extremity and low back injuries, and to identify the most appropriate methods to use for foot classification. A search of 5 electronic databases (PubMed, Embase, CINAHL, SPORTDiscus, and ProQuest Dissertations and Theses), Google Scholar, and the reference lists of included studies was conducted to identify relevant articles. The review included comparative cross-sectional, case-control, and prospective studies that reported qualitative/quantitative associations between foot types and lower extremity and back injuries. Quality of the selected studies was evaluated, and data synthesis for the level of association between foot types and injuries was conducted. A random-effects model was used to pool odds ratio (OR) and standardized mean difference (SMD) results for meta-analysis. Twenty-nine studies were included for meta-analysis. A significant association between nonneutral foot types and lower extremity injuries was determined (OR = 1.23; 95% confidence interval [CI]: 1.11, 1.37; P<.001). Foot posture index (OR = 2.58; 95% CI: 1.33, 5.02; P<.01) and visual/physical examination (OR = 1.17; 95% CI: 1.06, 1.28; P<.01) were 2 assessment methods using distinct foot-type categories that showed a significant association with lower extremity injuries. For foot-assessment methods using a continuous scale, measurements of lateral calcaneal pitch angle (SMD, 1.92; 95% CI: 1.44, 2.39; P<.00001), lateral talocalcaneal angle (SMD, 1.36; 95% CI: 0.93, 1.80; P<.00001), and navicular height (SMD, 0.34; 95% CI: 0.16, 0.52; P<.001) showed significant effect sizes in identifying high-arch foot, whereas the navicular drop test (SMD, 0.45; 95% CI: 0.03, 0.87; P<.05) and relaxed calcaneal stance position (SMD, 0.49; 95% CI: 0.01, 0.97; P<.05) displayed significant effect sizes in identifying flatfoot. Subgroup analyses revealed no significant

Sample size and power considerations in network meta-analysis

PubMed Central

2012-01-01

Background Network meta-analysis is becoming increasingly popular for establishing comparative effectiveness among multiple interventions for the same disease. Network meta-analysis inherits all methodological challenges of standard pairwise meta-analysis, but with increased complexity due to the multitude of intervention comparisons. One issue that is now widely recognized in pairwise meta-analysis is the issue of sample size and statistical power. This issue, however, has so far only received little attention in network meta-analysis. To date, no approaches have been proposed for evaluating the adequacy of the sample size, and thus power, in a treatment network. Findings In this article, we develop easy-to-use flexible methods for estimating the ‘effective sample size’ in indirect comparison meta-analysis and network meta-analysis. The effective sample size for a particular treatment comparison can be interpreted as the number of patients in a pairwise meta-analysis that would provide the same degree and strength of evidence as that which is provided in the indirect comparison or network meta-analysis. We further develop methods for retrospectively estimating the statistical power for each comparison in a network meta-analysis. We illustrate the performance of the proposed methods for estimating effective sample size and statistical power using data from a network meta-analysis on interventions for smoking cessation including over 100 trials. Conclusion The proposed methods are easy to use and will be of high value to regulatory agencies and decision makers who must assess the strength of the evidence supporting comparative effectiveness estimates. PMID:22992327

Global meta-analysis reveals low consistency of biodiversity congruence relationships.

PubMed

Westgate, Martin J; Barton, Philip S; Lane, Peter W; Lindenmayer, David B

2014-05-21

Knowledge of the number and distribution of species is fundamental to biodiversity conservation efforts, but this information is lacking for the majority of species on earth. Consequently, subsets of taxa are often used as proxies for biodiversity; but this assumes that different taxa display congruent distribution patterns. Here we use a global meta-analysis to show that studies of cross-taxon congruence rarely give consistent results. Instead, species richness congruence is highest at extreme spatial scales and close to the equator, while congruence in species composition is highest at large extents and grain sizes. Studies display highest variance in cross-taxon congruence when conducted in areas with dissimilar areal extents (for species richness) or latitudes (for species composition). These results undermine the assumption that a subset of taxa can be representative of biodiversity. Therefore, researchers whose goal is to prioritize locations or actions for conservation should use data from a range of taxa.

Game-based digital interventions for depression therapy: a systematic review and meta-analysis.

PubMed

Li, Jinhui; Theng, Yin-Leng; Foo, Schubert

2014-08-01

The aim of this study was to review the existing literature on game-based digital interventions for depression systematically and examine their effectiveness through a meta-analysis of randomized controlled trials (RCTs). Database searching was conducted using specific search terms and inclusion criteria. A standard meta-analysis was also conducted of available RCT studies with a random effects model. The standard mean difference (Cohen's d) was used to calculate the effect size of each study. Nineteen studies were included in the review, and 10 RCTs (eight studies) were included in the meta-analysis. Four types of game interventions-psycho-education and training, virtual reality exposure therapy, exercising, and entertainment-were identified, with various types of support delivered and populations targeted. The meta-analysis revealed a moderate effect size of the game interventions for depression therapy at posttreatment (d=-0.47 [95% CI -0.69 to -0.24]). A subgroup analysis showed that interventions based on psycho-education and training had a smaller effect than those based on the other forms, and that self-help interventions yielded better outcomes than supported interventions. A higher effect was achieved when a waiting list was used as the control. The review and meta-analysis support the effectiveness of game-based digital interventions for depression. More large-scale, high-quality RCT studies with sufficient long-term data for treatment evaluation are needed.

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

PubMed

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.

Effectiveness of problem-based learning in Chinese pharmacy education: a meta-analysis.

PubMed

Zhou, Jiyin; Zhou, Shiwen; Huang, Chunji; Xu, Rufu; Zhang, Zuo; Zeng, Shengya; Qian, Guisheng

2016-01-19

This review provides a critical overview of problem-based learning (PBL) practices in Chinese pharmacy education. PBL has yet to be widely applied in pharmaceutical education in China. The results of those studies that have been conducted are published in Chinese and thus may not be easily accessible to international researchers. Therefore, this meta-analysis was carried out to review the effectiveness of PBL. Databases were searched for studies in accordance with the inclusion criteria. Two reviewers independently performed the study identification and data extraction. A meta-analysis was conducted using Revman 5.3 software. Sixteen randomized controlled trials were included. The meta-analysis revealed that PBL had a positive association with higher theoretical scores (SMD = 1.17, 95% CI [0.77, 11.57], P < 0.00001). The questionnaire results show that PBL methods are superior to conventional teaching methods in improving students' learning interest, independent analysis skills, scope of knowledge, self-study, team spirit, and oral expression. This meta-analysis indicates that PBL pedagogy is superior to traditional lecture-based teaching in Chinese pharmacy education. PBL methods could be an optional, supplementary method of pharmaceutical teaching in China. However, Chinese pharmacy colleges and universities should revise PBL curricula according to their own needs, which would maximize the effectiveness of PBL.

[Hemispheric asymmetry modulation for language processing in aging: meta-analysis of studies using the dichotic listening test].

PubMed

Vanhoucke, Elodie; Cousin, Emilie; Baciu, Monica

2013-03-01

Growing evidence suggests that age impacts on interhemispheric representation of language. Dichotic listening test allows assessing language lateralization for spoken language and it generally reveals right-ear/left-hemisphere (LH) predominance for language in young adult subjects. According to reported results, elderly would display increasing LH predominance in some studies or stable LH language lateralization for language in others ones. The aim of this study was to depict the main pattern of results in respect with the effect of normal aging on the hemisphere specialization for language by using dichotic listening test. A meta-analysis based on 11 studies has been performed. The inter-hemisphere asymmetry does not seem to increase according to age. A supplementary qualitative analysis suggests that right-ear advantage seems to increase between 40 and 49 y old and becomes stable or decreases after 55 y old, suggesting right-ear/LH decline.

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

PubMed

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.

Parental, child, and adolescent experience of chronic skin conditions: A meta-ethnography and review of the qualitative literature.

PubMed

Ablett, Kate; Thompson, Andrew R

2016-12-01

Childhood skin conditions can affect the quality of life of children, adolescents, and families. As such, paediatric dermatological conditions have been the focus of a number of qualitative studies and there is now a need to integrate the findings. A meta-ethnography was carried out with the existing 12 studies, which included nine studies examining parental experiences and three studies of child experiences. Meta-ethnographic analysis of the studies identified themes focused on the child's sense of stigmatisation and the challenges for families that arose from this. Common experiences across studies were feelings of difference relating to the appearance of the skin. The results highlight that children and adolescents can experience negative social reactions and that parents may struggle with some aspects of the physical management of the condition. The studies indicate the need to examine in more detail the psychosocial aspects of childhood skin conditions and the role played by stigmatisation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Associations between interleukin-10 polymorphisms and susceptibility to juvenile idiopathic arthritis: a systematic review and meta-analysis.

PubMed

Harsini, Sara; Saghazadeh, Amene; Nedjat, Saharnaz; Rezaei, Nima

2018-03-01

Cytokine genes, including interleukin-10 (IL-10), are known to play important roles in the pathogenesis of juvenile idiopathic arthritis (JIA). This study aims to determine whether the IL-10 polymorphisms confer susceptibility to JIA. A meta-analysis was performed on the associations between the IL-10 -1082 G/A, -592 C/A, and -819 C/T polymorphisms and JIA. A total number of 7 studies involving 1,785 patients and 6,142 controls were considered in the meta-analysis. Meta-analysis of the IL-10 -592 C/A and -819 C/T polymorphisms showed no association with JIA in the study participants, or in Caucasian or Middle Eastern participants. Meta-analysis of the IL-10 -1082 A allele in all study participants, Caucasian and Middle Eastern, showed significant associations with RA (overall ORs were 1.17, 1.15, and 1.41, respectively). Meta-analysis of the AA versus GG genotype of the IL-10 -1082 G/A polymorphism revealed significant associations with JIA (OR = 3.66, 95% CI = 1.44-9.29, P = 0.006) in participants from Middle Eastern countries. Additionally, meta-analysis of the GG versus AA+GA genotypes of the IL-10 -1082 G/A polymorphism revealed the GG genotype as the protective factor against JIA in the Middle Eastern subgroup (OR = 0.44, 95% CI = 0.20-0.94, P = 0,04). Moreover, meta-analysis of the IL-10 -1082 A allele in 4 studies on Hardy-Weinberg equilibrium showed a significant association with JIA (OR = 1.17, 95% CI = 1.07-1.28, P = 0.0009). No association was found between the IL-10 (-1082, -819, -592) ACC, ATA, and GCC haplotypes and JIA. These results suggest that the IL-10 -1082 G/A polymorphism confers susceptibility to JIA.

How new graduate nurses experience patient death: A systematic review and qualitative meta-synthesis.

PubMed

Zheng, Ruishuang; Lee, Susan Fiona; Bloomer, Melissa Jane

2016-01-01

Patient death is an emotional and demanding experience for nurses, especially for new graduate nurses who are unprepared to deliver end-of-life care. Understanding new graduate nurses' experience of death and dying will inform the design of training programs and interventions for improvements in the quality of care and support of new graduates. To summarize new graduate nurses' experience with patient death by examining the findings of existing qualitative studies. Systematic review methods incorporating meta-synthesis were used. A comprehensive search was conducted in 12 databases from January 1990 to December 2014. All qualitative and mixed-method studies in English and Chinese that explored new graduate nurses' experience of patient death were included. Two independent reviewers selected the studies for inclusion and assessed each study quality. Meta-aggregation was performed to synthesize the findings of the included studies. Five primary qualitative studies and one mix-method study met inclusion and quality criteria. Six key themes were identified from the original findings: emotional experiences, facilitating a good death, support for family, inadequacy on end-of-life care issues, personal and professional growth and coping strategies. New graduate nurses expressed a variety of feelings when faced with patient death, but still they tried to facilitate a good death for dying patients and provide support for their families. The nurses benefited from this challenging encounter though they lacked of coping strategies. Copyright © 2015. Published by Elsevier Ltd.

GWAMA: software for genome-wide association meta-analysis.

PubMed

Mägi, Reedik; Morris, Andrew P

2010-05-28

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. 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. 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-study of qualitative research examining determinants of children's independent active free play.

PubMed

Lee, Homan; Tamminen, Katherine A; Clark, Alexander M; Slater, Linda; Spence, John C; Holt, Nicholas L

2015-01-24

To produce a meta-study by completing a systematic review of qualitative research examining determinants of independent active free play in children. Following systematic electronic and manual searches and application of inclusion/exclusion criteria, 46 studies were retained and subjected to meta-method, meta-theory, and meta-data analyses, followed by a final meta-synthesis. Identified determinants of independent active free play were child characteristics (age, competence, and gender), parental restrictions (safety concerns and surveillance), neighborhood and physical environment (fewer children to play with, differences in preferences for play spaces between parents and children, accessibility and proximity, and maintenance), societal changes (reduced sense of community, good parenting ideal, changing roles of parents, privatization of playtime and play spaces), and policy issues (need to give children voice). An ecological model depicting these factors, and the relationships therein, was created. This comprehensive meta-study helps establish a knowledge base for children's independent active free play research by synthesizing a previously fragmented set of studies. Parents' perceived safety concerns are the primary barrier to children's active free play. These safety concerns are moderated by child-level factors (age, competence, gender) and broader social issues. Interventions should focus on community-level solutions that include children's perspectives. From a methods perspective, the reviewed studies used a range of data collection techniques, but methodological details were often inadequately reported. The theoretical sophistication of research in this area could be improved. To this end, the synthesis reported in this study provides a framework for guiding future research.

Genetic Polymorphism of Angiotensin-Converting Enzyme and Chronic Obstructive Pulmonary Disease Risk: An Updated Meta-Analysis

PubMed Central

Kang, Sang Wook; Kim, Su Kang; Jung, Hee-Jae; Kim, Kwan-Il; Kim, Jinju

2016-01-01

The relationship between polymorphism of the angiotensin I converting enzyme (ACE) gene and chronic obstructive pulmonary disease (COPD) has been examined in many previous studies. However, their results were controversial. Therefore, we performed a meta-analysis to evaluate the relationship between the ACE gene and the risk of COPD. Fourteen case-control studies were included in this meta-analysis. The pooled p value, odds ratio (OR), and 95% confidence interval (95% CI) were used to investigate the strength of the association. The meta-analysis was performed using comprehensive meta-analysis software. Our meta-analysis results revealed that ACE polymorphisms were not related to the risk of COPD (p > 0.05 in each model). In further analyses based on ethnicity, we observed an association between insertion/deletion polymorphism of the ACE gene and risk of COPD in the Asian population (codominant 2, OR = 3.126, 95% CI = 1.919–5.093, p < 0.001; recessive, OR = 3.326, 95% CI = 2.190–5.050, p < 0.001) but not in the Caucasian population (p > 0.05 in each model). In conclusion, the present meta-analysis indicated that the insertion/deletion polymorphism of the ACE gene may be associated with susceptibility to COPD in the Asian population but not in the Caucasian population. However, the results of the present meta-analysis need to be confirmed in a larger sample. PMID:27830153

Integromics network meta-analysis on cardiac aging offers robust multi-layer modular signatures and reveals micronome synergism.

PubMed

Dimitrakopoulou, Konstantina; Vrahatis, Aristidis G; Bezerianos, Anastasios

2015-03-04

The avalanche of integromics and panomics approaches shifted the deciphering of aging mechanisms from single molecular entities to communities of them. In this orientation, we explore the cardiac aging mechanisms - risk factor for multiple cardiovascular diseases - by capturing the micronome synergism and detecting longevity signatures in the form of communities (modules). For this, we developed a meta-analysis scheme that integrates transcriptome expression data from multiple cardiac-specific independent studies in mouse and human along with proteome and micronome interaction data in the form of multiple independent weighted networks. Modularization of each weighted network produced modules, which in turn were further analyzed so as to define consensus modules across datasets that change substantially during lifespan. Also, we established a metric that determines - from the modular perspective - the synergism of microRNA-microRNA interactions as defined by significantly functionally associated targets. The meta-analysis provided 40 consensus integromics modules across mouse datasets and revealed microRNA relations with substantial collective action during aging. Three modules were reproducible, based on homology, when mapped against human-derived modules. The respective homologs mainly represent NADH dehydrogenases, ATP synthases, cytochrome oxidases, Ras GTPases and ribosomal proteins. Among various observations, we corroborate to the involvement of miR-34a (included in consensus modules) as proposed recently; yet we report that has no synergistic effect. Moving forward, we determined its age-related neighborhood in which HCN3, a known heart pacemaker channel, was included. Also, miR-125a-5p/-351, miR-200c/-429, miR-106b/-17, miR-363/-92b, miR-181b/-181d, miR-19a/-19b, let-7d/-7f, miR-18a/-18b, miR-128/-27b and miR-106a/-291a-3p pairs exhibited significant synergy and their association to aging and/or cardiovascular diseases is supported in many cases by a

Participation in mental healthcare: a qualitative meta-synthesis.

PubMed

Stomski, Norman J; Morrison, Paul

2017-01-01

Facilitation of service user participation in the co-production of mental healthcare planning and service delivery is an integral component of contemporary mental health policy and clinical guidelines. However, many service users continue to experience exclusion from the planning of their care. This review synthesizes qualitative research about participation in mental healthcare and articulates essential processes that enable service user participation in mental health care. Electronic databases were systematically searched. Studies were included if they were peer reviewed qualitative studies, published between 2000 and 2015, examining participation in mental health care. The Critical Appraisal Skills Program checklist was used to assess the quality of each included study. Constant comparison was used to identify similar constructs across several studies, which were then abstracted into thematic constructs. The synthesis resulted in the identification of six principal themes, which articulate key processes that facilitate service user participation in mental healthcare. These themes included: exercising influence; tokenism; sharing knowledge; lacking capacity; respect; and empathy. This meta-synthesis demonstrates that service user participation in mental healthcare remains a policy aspiration, which generally has not been translated into clinical practice. The continued lack of impact on policy on the delivery of mental healthcare suggests that change may have to be community driven. Systemic service user advocacy groups could contribute critically to promoting authentic service user participation in the co-production of mental health services.

MODEL-DRIVEN META-ANALYSES FOR INFORMING HEALTH CARE: A DIABETES META-ANALYSIS AS AN EXEMPLAR

PubMed Central

Brown, Sharon A.; Becker, Betsy Jane; García, Alexandra A.; Brown, Adama; Ramírez, Gilbert

2015-01-01

A relatively novel type of meta-analysis, a model-driven meta-analysis, involves the quantitative synthesis of descriptive, correlational data and is useful for identifying key predictors of health outcomes and informing clinical guidelines. Few such meta-analyses have been conducted and thus, large bodies of research remain unsynthesized and uninterpreted for application in health care. We describe the unique challenges of conducting a model-driven meta-analysis, focusing primarily on issues related to locating a sample of published and unpublished primary studies, extracting and verifying descriptive and correlational data, and conducting analyses. A current meta-analysis of the research on predictors of key health outcomes in diabetes is used to illustrate our main points. PMID:25142707

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

PubMed Central

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

Bayesian Meta-Analysis of Coefficient Alpha

ERIC Educational Resources Information Center

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…

The Impact of Aortic Occlusion Balloon on Mortality After Endovascular Repair of Ruptured Abdominal Aortic Aneurysms: A Meta-analysis and Meta-regression Analysis.

PubMed

Karkos, Christos D; Papadimitriou, Christina T; Chatzivasileiadis, Theodoros N; Kapsali, Nikoletta S; Kalogirou, Thomas E; Giagtzidis, Ioakeim T; Papazoglou, Konstantinos O

2015-12-01

We aimed to investigate whether the use of aortic occlusion balloon (AOB) has an impact on mortality of patients undergoing endovascular repair of ruptured abdominal aortic aneurysms (RAAAs). A meta-analysis of the English-language literature was undertaken through February 2013. Articles reporting data on outcome after endovascular repair of RAAAs were identified and information regarding the use of AOB was sought. Included in this meta-analysis were 39 eligible studies reporting 1277 patients. The pooled perioperative mortality was 21.6% (95% CI 18.1-25.1%). There was significant within-study heterogeneity (I(2) 50.2%, P < 0.001). A total of 200 patients required AOB with an estimated pooled proportion of 14.1% (8.9-19.3%). Individual random-effects meta-regression investigating the effect of AOB and other risk factors on mortality revealed a significant linear association of hemodynamic instability, bifurcated endograft approach, and primary conversion to open repair with mortality and a nonlinear (second degree polynomial) association of AOB with mortality. On multivariable meta-regression models, both hemodynamic instability and AOB were found to be statistically significant, independent predictors of mortality. In particular, there was a statistically significant negative correlation between AOB and mortality and a positive effect of hemodynamic instability on mortality. In practical terms, mortality was significantly higher in studies with a higher proportion of hemodynamically unstable patients and lower in studies with a higher rate of AOB use. This study provides meta-analytical evidence that the use of an AOB in unstable RAAA patients undergoing endovascular repair may improve the results.

Model-driven meta-analyses for informing health care: a diabetes meta-analysis as an exemplar.

PubMed

Brown, Sharon A; Becker, Betsy Jane; García, Alexandra A; Brown, Adama; Ramírez, Gilbert

2015-04-01

A relatively novel type of meta-analysis, a model-driven meta-analysis, involves the quantitative synthesis of descriptive, correlational data and is useful for identifying key predictors of health outcomes and informing clinical guidelines. Few such meta-analyses have been conducted and thus, large bodies of research remain unsynthesized and uninterpreted for application in health care. We describe the unique challenges of conducting a model-driven meta-analysis, focusing primarily on issues related to locating a sample of published and unpublished primary studies, extracting and verifying descriptive and correlational data, and conducting analyses. A current meta-analysis of the research on predictors of key health outcomes in diabetes is used to illustrate our main points. © The Author(s) 2014.

Meta-Analysis of Personality Traits in Alzheimer’s Disease: A Comparison with Healthy Subjects

PubMed Central

D’Iorio, Alfonsina; Garramone, Federica; Piscopo, Fausta; Baiano, Chiara; Raimo, Simona; Santangelo, Gabriella

2018-01-01

Background: The role of specific personality traits as factor risks of Alzheimer’s disease (AD) has been consistently found, whereas personality traits specifically related to AD (after the diagnosis) have not been outlined yet. Objective: A meta-analysis of published studies was performed to determine whether AD patients have a distinctive personality trait profile compared to healthy subjects (HC), similar to or different from a premorbid personality profile consistently reported in previous studies. Methods: A systematic literature search was performed using PsycInfo (PROQUEST), PubMed, and Scopus. The meta-analysis pooled results from primary studies using Hedges’ g unbiased approach. Results: The meta-analysis included 10 primary studies and revealed that, when the personality was evaluated by informant-rated measures, AD patients had significantly higher levels of Neuroticism, lower levels of Openness, Agreeableness, Conscientiousness, and Extraversion than HCs. When the personality was evaluated by self-rated measures, the results obtained from informants were confirmed for Neuroticism, Openness, and Extraversion but not for Agreeableness and Conscientiousness where AD patients and HCs achieved similar scores. Conclusions: The meta-analysis revealed that high Neuroticism and low Openness and Extraversion are distinctive personality traits significantly associated with a diagnosis of AD when evaluated both self-rated and informant-rated measures. This personality trait profile is similar to premorbid one, which contributes to development of AD over time. Therefore, our findings indirectly support the idea of specific premorbid personality traits as harbingers of AD. PMID:29480186

Trial Sequential Methods for Meta-Analysis

ERIC Educational Resources Information Center

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…

Game-Based Digital Interventions for Depression Therapy: A Systematic Review and Meta-Analysis

PubMed Central

Theng, Yin-Leng; Foo, Schubert

2014-01-01

Abstract The aim of this study was to review the existing literature on game-based digital interventions for depression systematically and examine their effectiveness through a meta-analysis of randomized controlled trials (RCTs). Database searching was conducted using specific search terms and inclusion criteria. A standard meta-analysis was also conducted of available RCT studies with a random effects model. The standard mean difference (Cohen's d) was used to calculate the effect size of each study. Nineteen studies were included in the review, and 10 RCTs (eight studies) were included in the meta-analysis. Four types of game interventions—psycho-education and training, virtual reality exposure therapy, exercising, and entertainment—were identified, with various types of support delivered and populations targeted. The meta-analysis revealed a moderate effect size of the game interventions for depression therapy at posttreatment (d=−0.47 [95% CI −0.69 to −0.24]). A subgroup analysis showed that interventions based on psycho-education and training had a smaller effect than those based on the other forms, and that self-help interventions yielded better outcomes than supported interventions. A higher effect was achieved when a waiting list was used as the control. The review and meta-analysis support the effectiveness of game-based digital interventions for depression. More large-scale, high-quality RCT studies with sufficient long-term data for treatment evaluation are needed. PMID:24810933

Meta-analysis in Stata using gllamm.

PubMed

Bagos, Pantelis G

2015-12-01

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 correlated estimates, for multilevel or hierarchical meta-analysis, or for meta-analysis of longitudinal data. In this work, we show with practical applications that many disparate models, including but not limited to the ones mentioned earlier, can be fitted using gllamm. The software is very versatile and can handle a wide variety of models with applications in a wide range of disciplines. The method presented here takes advantage of these modeling capabilities and makes use of appropriate transformations, based on the Cholesky decomposition of the inverse of the covariance matrix, known as generalized least squares, in order to handle correlated data. The models described earlier can be thought of as special instances of a general linear mixed-model formulation, but to the author's knowledge, a general exposition in order to incorporate all the available models for meta-analysis as special cases and the instructions to fit them in Stata has not been presented so far. Source code is available at http:www.compgen.org/tools/gllamm. Copyright © 2015 John Wiley & Sons, Ltd.

[Why evidence-based medicine? 20 years of meta-analysis].

PubMed

Ceballos, C; Valdizán, J R; Artal, A; Almárcegui, C; Allepuz, C; García Campayo, J; Fernández Liesa, R; Giraldo, P; Puértolas, T

2000-10-01

Meta-analysis, described within evidence-based medicine, has become a frequent issue in recent medical literature. An exhaustive search of reported meta-analysis from any medical specialty is described. Search of papers included in Medline or Embase between 1973-1998. A study of intra and inter-reviewers liability about selection and classification have been performed. A descriptive analysis of the reported papers (frequency tables and graphics) is described, including differences of mean of reported meta-analysis papers by medical specialty and year. 1,518 papers were selected and classified. Most frequently found (45.91%) were: methodology (15.7%), psychiatry (11.79%), cardiology (10.01%) and oncology (8.36%). Inter personal agreement was 0.93 in selecting papers and 0.72 in classifying them. Between 1977-1987 overall mean of reported studies of meta-analysis (1.67 + 4.10) was significatively inferior to the 1988-1998 (49.54 + 56.55) (p < 0.001). Global number of meta-analysis was positively correlated (p < 0.05) with the number of studies about fundamentals and methodology during the study period. The method used to identify meta-analysis reports can be considered to be adequate; however, the agreement in classifying them in medical specialties was inferior. A progressive increase in the number of reported meta-analysis since 1977 can be demonstrated. Specialties with a greater number of meta-analysis published in the literature were: psychiatry, oncology and cardiology. Diffusion of knowledge about fundamentals and methodology of meta-analysis seems to have drawn and increase in performing and reporting this kind of analysis.

The complex genetics of gait speed: genome-wide meta-analysis approach

PubMed Central

Lunetta, Kathryn L.; Smith, Jennifer A.; Eicher, John D.; Vered, Rotem; Deelen, Joris; Arnold, Alice M.; Buchman, Aron S.; Tanaka, Toshiko; Faul, Jessica D.; Nethander, Maria; Fornage, Myriam; Adams, Hieab H.; Matteini, Amy M.; Callisaya, Michele L.; Smith, Albert V.; Yu, Lei; De Jager, Philip L.; Evans, Denis A.; Gudnason, Vilmundur; Hofman, Albert; Pattie, Alison; Corley, Janie; Launer, Lenore J.; Knopman, Davis S.; Parimi, Neeta; Turner, Stephen T.; Bandinelli, Stefania; Beekman, Marian; Gutman, Danielle; Sharvit, Lital; Mooijaart, Simon P.; Liewald, David C.; Houwing-Duistermaat, Jeanine J.; Ohlsson, Claes; Moed, Matthijs; Verlinden, Vincent J.; Mellström, Dan; van der Geest, Jos N.; Karlsson, Magnus; Hernandez, Dena; McWhirter, Rebekah; Liu, Yongmei; Thomson, Russell; Tranah, Gregory J.; Uitterlinden, Andre G.; Weir, David R.; Zhao, Wei; Starr, John M.; Johnson, Andrew D.; Ikram, M. Arfan; Bennett, David A.; Cummings, Steven R.; Deary, Ian J.; Harris, Tamara B.; Kardia, Sharon L. R.; Mosley, Thomas H.; Srikanth, Velandai K.; Windham, Beverly G.; Newman, Ann B.; Walston, Jeremy D.; Davies, Gail; Evans, Daniel S.; Slagboom, Eline P.; Ferrucci, Luigi; Kiel, Douglas P.; Murabito, Joanne M.; Atzmon, Gil

2017-01-01

Emerging evidence suggests that the basis for variation in late-life mobility is attributable, in part, to genetic factors, which may become increasingly important with age. Our objective was to systematically assess the contribution of genetic variation to gait speed in older individuals. We conducted a meta-analysis of gait speed GWASs in 31,478 older adults from 17 cohorts of the CHARGE consortium, and validated our results in 2,588 older adults from 4 independent studies. We followed our initial discoveries with network and eQTL analysis of candidate signals in tissues. The meta-analysis resulted in a list of 536 suggestive genome wide significant SNPs in or near 69 genes. Further interrogation with Pathway Analysis placed gait speed as a polygenic complex trait in five major networks. Subsequent eQTL analysis revealed several SNPs significantly associated with the expression of PRSS16, WDSUB1 and PTPRT, which in addition to the meta-analysis and pathway suggested that genetic effects on gait speed may occur through synaptic function and neuronal development pathways. No genome-wide significant signals for gait speed were identified from this moderately large sample of older adults, suggesting that more refined physical function phenotypes will be needed to identify the genetic basis of gait speed in aging. PMID:28077804

Examining Ecological Constraints on the Intergenerational Transmission of Attachment Via Individual Participant Data Meta-analysis.

PubMed

Verhage, Marije L; Fearon, R M Pasco; Schuengel, Carlo; van IJzendoorn, Marinus H; Bakermans-Kranenburg, Marian J; Madigan, Sheri; Roisman, Glenn I; Oosterman, Mirjam; Behrens, Kazuko Y; Wong, Maria S; Mangelsdorf, Sarah; Priddis, Lynn E; Brisch, Karl-Heinz

2018-05-09

Parents' attachment representations and child-parent attachment have been shown to be associated, but these associations vary across populations (Verhage et al., 2016). The current study examined whether ecological factors may explain variability in the strength of intergenerational transmission of attachment, using individual participant data (IPD) meta-analysis. Analyses on 4,396 parent-child dyads (58 studies, child age 11-96 months) revealed a combined effect size of r = .29. IPD meta-analyses revealed that effect sizes for the transmission of autonomous-secure representations to secure attachments were weaker under risk conditions and weaker in adolescent parent-child dyads, whereas transmission was stronger for older children. Findings support the ecological constraints hypothesis on attachment transmission. Implications for attachment theory and the use of IPD meta-analysis are discussed. © 2018 The Authors. Child Development published by Wiley Periodicals, Inc. on behalf of Society for Research in Child Development.

A Meta-Synthesis of Qualitative Findings About Dance/Movement Therapy for Individuals With Trauma.

PubMed

Levine, Brooklyn; Land, Helen M

2016-02-01

The therapeutic potential of using dance/movement therapy is being increasingly recognized. Preliminary interdisciplinary research findings suggest engaging the body in trauma treatment might reduce the length of treatment by addressing the connections among thoughts, feelings, neurobiology, and somatic responses in the survivor. Unfortunately, empirical research investigating its effectiveness as a psychotherapeutic intervention has been limited due to the lack of a clear manual for mental health care practitioners. The present study aims to synthesize findings from the existing qualitative literature in a qualitative meta-synthesis. Our findings will contribute to the development of a body-oriented intervention for mental health care practitioners to use for trauma. © The Author(s) 2015.

Adding results to a meta-analysis: Theory and example

NASA Astrophysics Data System (ADS)

Willson, Victor L.

Meta-analysis has been used as a research method to describe bodies of research data. It promotes hypothesis formation and the development of science education laws. A function overlooked, however, is the role it plays in updating research. Methods to integrate new research with meta-analysis results need explication. A procedure is presented using Bayesian analysis. Research in science education attitude correlation with achievement has been published after a recent meta-analysis of the topic. The results show how new findings complement the previous meta-analysis and extend its conclusions. Additional methodological questions adddressed are how studies are to be weighted, which variables are to be examined, and how often meta-analysis are to be updated.

Benzodiazepines for PTSD: A Systematic Review and Meta-Analysis.

PubMed

Guina, Jeffrey; Rossetter, Sarah R; DeRHODES, Bethany J; Nahhas, Ramzi W; Welton, Randon S

2015-07-01

Although benzodiazepines (BZDs) are commonly used in the treatment of posttraumatic stress disorder (PTSD), no systematic review or meta-analysis has specifically examined this treatment. The goal of this study was to analyze and summarize evidence concerning the efficacy of BZDs in treating PTSD. The review protocol was undertaken according to the principles recommended by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and is registered with the PROSPERO international prospective register of systematic reviews (http://www.crd.york.ac.uk/PROSPERO, registration number CRD42014009318). Two authors independently conducted a search of all relevant articles using multiple electronic databases and independently abstracted information from studies measuring PTSD outcomes in patients using BZDs. Eighteen clinical trials and observational studies were identified, with a total of 5236 participants. Outcomes were assessed using qualitative and quantitative syntheses, including meta-analysis. BZDs are ineffective for PTSD treatment and prevention, and risks associated with their use tend to outweigh potential short-term benefits. In addition to adverse effects in general populations, BZDs are associated with specific problems in patients with PTSD: worse overall severity, significantly increased risk of developing PTSD with use after recent trauma, worse psychotherapy outcomes, aggression, depression, and substance use. Potential biopsychosocial explanations for these results are proposed based on studies that have investigated BZDs, PTSD, and relevant animal models. The results of this systematic review suggest that BZDs should be considered relatively contraindicated for patients with PTSD or recent trauma. Evidence-based treatments for PTSD should be favored over BZDs.

Meta-Analysis in Stata Using Gllamm

ERIC Educational Resources Information Center

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…

Effectiveness of Various Innovative Learning Methods in Health Science Classrooms: A Meta-Analysis

ERIC Educational Resources Information Center

Kalaian, Sema A.; Kasim, Rafa M.

2017-01-01

This study reports the results of a meta-analysis of the available literature on the effectiveness of various forms of innovative small-group learning methods on student achievement in undergraduate college health science classrooms. The results of the analysis revealed that most of the primary studies supported the effectiveness of the…

The more total cognitive load is reduced by cues, the better retention and transfer of multimedia learning: A meta-analysis and two meta-regression analyses.

PubMed

Xie, Heping; Wang, Fuxing; Hao, Yanbin; Chen, Jiaxue; An, Jing; Wang, Yuxin; Liu, Huashan

2017-01-01

Cueing facilitates retention and transfer of multimedia learning. From the perspective of cognitive load theory (CLT), cueing has a positive effect on learning outcomes because of the reduction in total cognitive load and avoidance of cognitive overload. However, this has not been systematically evaluated. Moreover, what remains ambiguous is the direct relationship between the cue-related cognitive load and learning outcomes. A meta-analysis and two subsequent meta-regression analyses were conducted to explore these issues. Subjective total cognitive load (SCL) and scores on a retention test and transfer test were selected as dependent variables. Through a systematic literature search, 32 eligible articles encompassing 3,597 participants were included in the SCL-related meta-analysis. Among them, 25 articles containing 2,910 participants were included in the retention-related meta-analysis and the following retention-related meta-regression, while there were 29 articles containing 3,204 participants included in the transfer-related meta-analysis and the transfer-related meta-regression. The meta-analysis revealed a statistically significant cueing effect on subjective ratings of cognitive load (d = -0.11, 95% CI = [-0.19, -0.02], p < 0.05), retention performance (d = 0.27, 95% CI = [0.08, 0.46], p < 0.01), and transfer performance (d = 0.34, 95% CI = [0.12, 0.56], p < 0.01). The subsequent meta-regression analyses showed that dSCL for cueing significantly predicted dretention for cueing (β = -0.70, 95% CI = [-1.02, -0.38], p < 0.001), as well as dtransfer for cueing (β = -0.60, 95% CI = [-0.92, -0.28], p < 0.001). Thus in line with CLT, adding cues in multimedia materials can indeed reduce SCL and promote learning outcomes, and the more SCL is reduced by cues, the better retention and transfer of multimedia learning.

The more total cognitive load is reduced by cues, the better retention and transfer of multimedia learning: A meta-analysis and two meta-regression analyses

PubMed Central

Hao, Yanbin; Chen, Jiaxue; An, Jing; Wang, Yuxin; Liu, Huashan

2017-01-01

Cueing facilitates retention and transfer of multimedia learning. From the perspective of cognitive load theory (CLT), cueing has a positive effect on learning outcomes because of the reduction in total cognitive load and avoidance of cognitive overload. However, this has not been systematically evaluated. Moreover, what remains ambiguous is the direct relationship between the cue-related cognitive load and learning outcomes. A meta-analysis and two subsequent meta-regression analyses were conducted to explore these issues. Subjective total cognitive load (SCL) and scores on a retention test and transfer test were selected as dependent variables. Through a systematic literature search, 32 eligible articles encompassing 3,597 participants were included in the SCL-related meta-analysis. Among them, 25 articles containing 2,910 participants were included in the retention-related meta-analysis and the following retention-related meta-regression, while there were 29 articles containing 3,204 participants included in the transfer-related meta-analysis and the transfer-related meta-regression. The meta-analysis revealed a statistically significant cueing effect on subjective ratings of cognitive load (d = −0.11, 95% CI = [−0.19, −0.02], p < 0.05), retention performance (d = 0.27, 95% CI = [0.08, 0.46], p < 0.01), and transfer performance (d = 0.34, 95% CI = [0.12, 0.56], p < 0.01). The subsequent meta-regression analyses showed that dSCL for cueing significantly predicted dretention for cueing (β = −0.70, 95% CI = [−1.02, −0.38], p < 0.001), as well as dtransfer for cueing (β = −0.60, 95% CI = [−0.92, −0.28], p < 0.001). Thus in line with CLT, adding cues in multimedia materials can indeed reduce SCL and promote learning outcomes, and the more SCL is reduced by cues, the better retention and transfer of multimedia learning. PMID:28854205

Using structural equation modeling for network meta-analysis.

PubMed

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

ERIC Educational Resources Information Center

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…

Combining aneuploidy and dysplasia for colitis' cancer risk assessment outperforms current surveillance efficiency: a meta-analysis.

PubMed

Meyer, Rüdiger; Freitag-Wolf, Sandra; Blindow, Silke; Büning, Jürgen; Habermann, Jens K

2017-02-01

Cancer risk assessment for ulcerative colitis patients by evaluating histological changes through colonoscopy surveillance is still challenging. Thus, additional parameters of high prognostic impact for the development of colitis-associated carcinoma are necessary. This meta-analysis was conducted to clarify the value of aneuploidy as predictor for individual cancer risk compared with current surveillance parameters. A systematic web-based search identified studies published in English that addressed the relevance of the ploidy status for individual cancer risk during surveillance in comparison to neoplastic mucosal changes. The resulting data were included into a meta-analysis, and odds ratios (OR) were calculated for aneuploidy or dysplasia or aneuploidy plus dysplasia. Twelve studies addressing the relevance of aneuploidy compared to dyplasia were comprehensively evaluated and further used for meta-analysis. The meta-analysis revealed that aneuploidy (OR 5.31 [95 % CI 2.03, 13.93]) is an equally effective parameter for cancer risk assessment in ulcerative colitis patients as dysplasia (OR 4.93 [1.61, 15.11]). Strikingly, the combined assessment of dysplasia and aneuploidy is superior compared to applying each parameter alone (OR 8.99 [3.08, 26.26]). This meta-analysis reveals that aneuploidy is an equally effective parameter for individual cancer risk assessment in ulcerative colitis as the detection of dysplasia. More important, the combined assessment of dysplasia and aneuploidy outperforms the use of each parameter alone. We suggest image cytometry for ploidy assessment to become an additional feature of consensus criteria to individually assess cancer risk in UC.

The Empirical Review of Meta-Analysis Published in Korea

ERIC Educational Resources Information Center

Park, Sunyoung; Hong, Sehee

2016-01-01

Meta-analysis is a statistical method that is increasingly utilized to combine and compare the results of previous primary studies. However, because of the lack of comprehensive guidelines for how to use meta-analysis, many meta-analysis studies have failed to consider important aspects, such as statistical programs, power analysis, publication…

Network meta-analysis, electrical networks and graph theory.

PubMed

Rücker, Gerta

2012-12-01

Network meta-analysis is an active field of research in clinical biostatistics. It aims to combine information from all randomized comparisons among a set of treatments for a given medical condition. We show how graph-theoretical methods can be applied to network meta-analysis. A meta-analytic graph consists of vertices (treatments) and edges (randomized comparisons). We illustrate the correspondence between meta-analytic networks and electrical networks, where variance corresponds to resistance, treatment effects to voltage, and weighted treatment effects to current flows. Based thereon, we then show that graph-theoretical methods that have been routinely applied to electrical networks also work well in network meta-analysis. In more detail, the resulting consistent treatment effects induced in the edges can be estimated via the Moore-Penrose pseudoinverse of the Laplacian matrix. Moreover, the variances of the treatment effects are estimated in analogy to electrical effective resistances. It is shown that this method, being computationally simple, leads to the usual fixed effect model estimate when applied to pairwise meta-analysis and is consistent with published results when applied to network meta-analysis examples from the literature. Moreover, problems of heterogeneity and inconsistency, random effects modeling and including multi-armed trials are addressed. Copyright © 2012 John Wiley & Sons, Ltd. Copyright © 2012 John Wiley & Sons, Ltd.

The efficiency of health care production in OECD countries: A systematic review and meta-analysis of cross-country comparisons.

PubMed

Varabyova, Yauheniya; Müller, Julia-Maria

2016-03-01

There has been an ongoing interest in the analysis and comparison of the efficiency of health care systems using nonparametric and parametric applications. The objective of this study was to review the current state of the literature and to synthesize the findings on health system efficiency in OECD countries. We systematically searched five electronic databases through August 2014 and identified 22 studies that analyzed the efficiency of health care production at the country level. We summarized these studies with view on their sample, methods, and utilized variables. We developed and applied a checklist of 14 items to assess the quality of the reviewed studies along four dimensions: reporting, external validity, bias, and power. Moreover, to examine the internal validity of findings we meta-analyzed the efficiency estimates reported in 35 models from ten studies. The qualitative synthesis of the literature indicated large differences in study designs and methods. The meta-analysis revealed low correlations between country rankings suggesting a lack of internal validity of the efficiency estimates. In conclusion, methodological problems of existing cross-country comparisons of the efficiency of health care systems draw into question the ability of these comparisons to provide meaningful guidance to policy-makers. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

A Review of Meta-Analysis Packages in R

ERIC Educational Resources Information Center

Polanin, Joshua R.; Hennessy, Emily A.; Tanner-Smith, Emily E.

2017-01-01

Meta-analysis is a statistical technique that allows an analyst to synthesize effect sizes from multiple primary studies. To estimate meta-analysis models, the open-source statistical environment R is quickly becoming a popular choice. The meta-analytic community has contributed to this growth by developing numerous packages specific to…

Implementing informative priors for heterogeneity in meta-analysis using meta-regression and pseudo data.

PubMed

Rhodes, Kirsty M; Turner, Rebecca M; White, Ian R; Jackson, Dan; Spiegelhalter, David J; Higgins, Julian P T

2016-12-20

Many meta-analyses combine results from only a small number of studies, a situation in which the between-study variance is imprecisely estimated when standard methods are applied. Bayesian meta-analysis allows incorporation of external evidence on heterogeneity, providing the potential for more robust inference on the effect size of interest. We present a method for performing Bayesian meta-analysis using data augmentation, in which we represent an informative conjugate prior for between-study variance by pseudo data and use meta-regression for estimation. To assist in this, we derive predictive inverse-gamma distributions for the between-study variance expected in future meta-analyses. These may serve as priors for heterogeneity in new meta-analyses. In a simulation study, we compare approximate Bayesian methods using meta-regression and pseudo data against fully Bayesian approaches based on importance sampling techniques and Markov chain Monte Carlo (MCMC). We compare the frequentist properties of these Bayesian methods with those of the commonly used frequentist DerSimonian and Laird procedure. The method is implemented in standard statistical software and provides a less complex alternative to standard MCMC approaches. An importance sampling approach produces almost identical results to standard MCMC approaches, and results obtained through meta-regression and pseudo data are very similar. On average, data augmentation provides closer results to MCMC, if implemented using restricted maximum likelihood estimation rather than DerSimonian and Laird or maximum likelihood estimation. The methods are applied to real datasets, and an extension to network meta-analysis is described. The proposed method facilitates Bayesian meta-analysis in a way that is accessible to applied researchers. © 2016 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd. © 2016 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.

Motor function and incident dementia: a systematic review and meta-analysis.

PubMed

Kueper, Jacqueline Kathleen; Speechley, Mark; Lingum, Navena Rebecca; Montero-Odasso, Manuel

2017-09-01

cognitive and mobility decline are interrelated processes, whereby mobility decline coincides or precedes the onset of cognitive decline. to assess whether there is an association between performance on motor function tests and incident dementia. electronic database, grey literature and hand searching identified studies testing for associations between baseline motor function and incident dementia in older adults. of 2,540 potentially relevant documents, 37 met the final inclusion criteria and were reviewed qualitatively. Three meta-analyses were conducted using data from 10 studies. Three main motor domains-upper limb motor function, parkinsonism and lower limb motor function-emerged as associated with increased risk of incident dementia. Studies including older adults without neurological overt disease found a higher risk of incident dementia associated with poorer performance on composite motor function scores, balance and gait velocity (meta-analysis pooled HR = 1.94, 95% CI: 1.41, 2.65). Mixed results were found across different study samples for upper limb motor function, overall parkinsonism (meta-analysis pooled OR = 3.05, 95% CI: 1.31, 7.08), bradykinesia and rigidity. Studies restricted to older adults with Parkinson's Disease found weak or no association with incident dementia even for motor domains highly associated in less restrictive samples. Tremor was not associated with an increased risk of dementia in any population (meta-analysis pooled HR = 0.80, 95% CI 0.31, 2.03). lower limb motor function was associated with increased risk of developing dementia, while tremor and hand grip strength were not. Our results support future research investigating the inclusion of quantitative motor assessment, specifically gait velocity tests, for clinical dementia risk evaluation. © The Author 2017. Published by Oxford University Press on behalf of the British Geriatrics Society.All rights reserved. For permissions, please email: journals.permissions@oup.com

Cognitive functioning in patients with affective disorders and schizophrenia: a meta-analysis.

PubMed

Stefanopoulou, Evgenia; Manoharan, Andiappan; Landau, Sabine; Geddes, John R; Goodwin, Guy; Frangou, Sophia

2009-01-01

There is considerable evidence for cognitive dysfunction in schizophrenia and affective disorders, but the pattern of potential similarities or differences between diagnostic groups remains uncertain. The objective of this study was to conduct a quantitative review of studies on cognitive performance in schizophrenia and affective disorders. Relevant articles were identified through literature search in major databases for the period between January 1980 and December 2005. Meta-analytic treatment of the original studies revealed widespread cognitive deficits in patients with schizophrenia and affective disorders in intellectual ability and speed of information processing, in encoding and retrieval, rule discovery and in response generation and response inhibition. Differences between diagnostic groups were quantitative rather than qualitative.

The impact of pneumatic tube system on routine laboratory parameters: a systematic review and meta-analysis.

PubMed

Kapoula, Georgia V; Kontou, Panagiota I; Bagos, Pantelis G

2017-10-26

Pneumatic tube system (PTS) is a widely used method of transporting blood samples in hospitals. The aim of this study was to evaluate the effects of the PTS transport in certain routine laboratory parameters as it has been implicated with hemolysis. A systematic review and a meta-analysis were conducted. PubMed and Scopus databases were searched (up until November 2016) to identify prospective studies evaluating the impact of PTS transport in hematological, biochemical and coagulation measurements. The random-effects model was used in the meta-analysis utilizing the mean difference (MD). Heterogeneity was quantitatively assessed using the Cohran's Q and the I2 index. Subgroup analysis, meta-regression analysis, sensitivity analysis, cumulative meta-analysis and assessment of publication bias were performed for all outcomes. From a total of 282 studies identified by the searching procedure, 24 were finally included in the meta-analysis. The meta-analysis yielded statistically significant results for potassium (K) [MD=0.04 mmol/L; 95% confidence interval (CI)=0.015-0.065; p=0.002], lactate dehydrogenase (LDH) (MD=10.343 U/L; 95% CI=6.132-14.554; p<10-4) and aspartate aminotransferase (AST) (MD=1.023 IU/L; 95% CI=0.344-1.702; p=0.003). Subgroup analysis and random-effects meta-regression analysis according to the speed and distance of the samples traveled via the PTS revealed that there is relation between the rate and the distance of PTS with the measurements of K, LDH, white blood cells and red blood cells. This meta-analysis suggests that PTS may be associated with alterations in K, LDH and AST measurements. Although these findings may not have any significant clinical effect on laboratory results, it is wise that each hospital validates their PTS.

Why Do Rape Survivors Volunteer for Face-to-Face Interviews? A Meta-Study of Victims' Reasons for and Concerns about Research Participation

ERIC Educational Resources Information Center

Campbell, Rebecca; Adams, Adrienne E.

2009-01-01

There is growing interest in understanding how different research methods are perceived by victims of violence and what survivors will reveal to researchers (termed "meta-research" or "meta-studies"). The purpose of this project was to conduct a qualitative meta-study on why rape survivors chose to participate in community-based, face-to-face…

Understanding the complex interplay of barriers to physical activity amongst black and minority ethnic groups in the United Kingdom: a qualitative synthesis using meta-ethnography.

PubMed

Koshoedo, Sejlo A; Paul-Ebhohimhen, Virginia A; Jepson, Ruth G; Watson, Margaret C

2015-07-12

To conduct a meta-ethnographic analysis of qualitative studies to identify barriers to Black and Minority Ethnic (BME) individuals engaging in physical activity in the UK context. A qualitative synthesis using meta-ethnographic methods to synthesis studies of barriers to engaging in physical activity among BME groups in the UK. A comprehensive search strategy of multiple databases was employed to identify qualitative research studies published up to October 2012. The eleven searched databases included ASSIA, MEDLINE, EMBASE, CINAHL, Health Technology Assessment (HTA), NHS Scotland Library, Physical Activity Health Alliance (PAHA), PsyINFO, Social Services Abstract, Sport discuss and Web of Science. The Noblit and Hare's meta-ethnographic approach was undertaken to develop an inductive and interpretive form of knowledge synthesis. Fourteen papers met the inclusion criteria. The synthesis indicated that barriers to physical activity among BME individuals were influenced by four main concepts: perceptions; cultural expectations; personal barriers; and factors limiting access to facilities. BME individuals had different understandings of physical activity were influenced by migration history, experiences, cultural and health beliefs. This in turn may have a disempowering effect on BME individuals in terms of adopting or maintaining physical activity. These barriers to physical activity were explained at a higher conceptual level by a socio-ecological model. The social construct 'individual perception and understanding of physical activity' was particularly relevant to theoretical models and interventions. Interventions to promote engagement with physical activity need to address perceptions of this behaviour. The elicited concepts and contexts could be used to enhance the development of tailored effective health promotion interventions for BME individuals.

Fall-Risk-Increasing Drugs: A Systematic Review and Meta-analysis: III. Others.

PubMed

Seppala, Lotta J; van de Glind, Esther M M; Daams, Joost G; Ploegmakers, Kimberley J; de Vries, Max; Wermelink, Anne M A T; van der Velde, Nathalie

2018-04-01

The use of psychotropic medication and cardiovascular medication has been associated with an increased risk of falling. However, other frequently prescribed medication classes are still under debate as potential risk factors for falls in the older population. The aim of this systematic review and meta-analysis is to evaluate the associations between fall risk and nonpsychotropic and noncardiovascular medications. A systematic review and meta-analysis. A search was conducted in Medline, PsycINFO, and Embase. Key search concepts were "falls," "aged," "medication," and "causality." Studies were included that investigated nonpsychotropic and noncardiovascular medications as risk factors for falls in participants ≥60 years or participants with a mean age ≥70 years. A meta-analysis was performed using the generic inverse variance method, pooling unadjusted and adjusted odds ratio (OR) estimates separately. In a qualitative synthesis, 281 studies were included. The results of meta-analysis using adjusted data were as follows (a pooled OR [95% confidence interval]): analgesics, 1.42 (0.91-2.23); nonsteroidal anti-inflammatory drugs (NSAIDs), 1.09 (0.96-1.23); opioids, 1.60 (1.35-1.91); anti-Parkinson drugs, 1.54 (0.99-2.39); antiepileptics, 1.55 (1.25-1.92); and polypharmacy, 1.75 (1.27-2.41). Most of the meta-analyses resulted in substantial heterogeneity that did not disappear after stratification for population and setting in most cases. In a descriptive synthesis, consistent associations with falls were observed for long-term proton pump inhibitor use and opioid initiation. Laxatives showed inconsistent associations with falls (7/20 studies showing a positive association). Opioid and antiepileptic use and polypharmacy were significantly associated with increased risk of falling in the meta-analyses. Long-term use of proton pump inhibitors and opioid initiation might increase the fall risk. Future research is necessary because the causal role of some medication

Diagnostic accuracy of imaging devices in glaucoma: A meta-analysis.

PubMed

Fallon, Monica; Valero, Oliver; Pazos, Marta; Antón, Alfonso

Imaging devices such as the Heidelberg retinal tomograph-3 (HRT3), scanning laser polarimetry (GDx), and optical coherence tomography (OCT) play an important role in glaucoma diagnosis. A systematic search for evidence-based data was performed for prospective studies evaluating the diagnostic accuracy of HRT3, GDx, and OCT. The diagnostic odds ratio (DOR) was calculated. To compare the accuracy among instruments and parameters, a meta-analysis considering the hierarchical summary receiver-operating characteristic model was performed. The risk of bias was assessed using quality assessment of diagnostic accuracy studies, version 2. Studies in the context of screening programs were used for qualitative analysis. Eighty-six articles were included. The DOR values were 29.5 for OCT, 18.6 for GDx, and 13.9 for HRT. The heterogeneity analysis demonstrated statistically a significant influence of degree of damage and ethnicity. Studies analyzing patients with earlier glaucoma showed poorer results. The risk of bias was high for patient selection. Screening studies showed lower sensitivity values and similar specificity values when compared with those included in the meta-analysis. The classification capabilities of GDx, HRT, and OCT were high and similar across the 3 instruments. The highest estimated DOR was obtained with OCT. Diagnostic accuracy could be overestimated in studies including prediagnosed groups of subjects. Copyright © 2017 Elsevier Inc. All rights reserved.

Association between Homocysteine and Cerebral Small Vessel Disease: A Meta-Analysis.

PubMed

Piao, Xiangyu; Wu, Guangyao; Yang, Pei; Shen, Jing; De, Ailing; Wu, Jianlin; Qu, Qiumin

2018-05-22

This study aimed to evaluate whether elevated homocysteine levels is associated with risk of different subtypes of cerebral small vessel disease (CSVD) by using meta-analysis. Electronic databases were systematically searched up to April 2018 for collecting the studies reporting homocysteine levels in CSVD or CSVD subtypes. After an inclusion and exclusion criteria, the data was extracted. All data was analyzed using Stata software v.12.0 (Stata Corp LP, College Station, TX). The standardized mean difference (SMD) and 95% confidence interval (CI) were used to compare continuous variables. Eighteen studies met eligibility criteria with 5088 participants (1987 patients with CSVD and 3101 controls) included in the meta-analysis. Meta-analysis revealed that, compared with the controls group, the CSVD group had significantly higher homocysteine levels, with the SMD of .50 and 95% CI (.36-.64). Subgroup analyses suggested white matter lesion had significantly higher levels of homocysteine compared with controls (SMD = .56, 95% CI .39-.73), followed by silent brain infarction (SMD = .33, 95% CI .24-.42) and lacunar infarction (SMD = .17, 95% CI -.06 to .40). This meta-analysis found that CSVD or CSVD subtypes have a significantly higher homocysteine levels than in controls. Further prospective population-based studies are needed to longitudinally evaluate the association between homocysteine levels and progression of different CSVD subtypes. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Multivariate Methods for Meta-Analysis of Genetic Association Studies.

PubMed

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.

Comparison of variance estimators for meta-analysis of instrumental variable estimates

PubMed Central

Schmidt, AF; Hingorani, AD; Jefferis, BJ; White, J; Groenwold, RHH; Dudbridge, F

2016-01-01

Abstract Background: Mendelian randomization studies perform instrumental variable (IV) analysis using genetic IVs. Results of individual Mendelian randomization studies can be pooled through meta-analysis. We explored how different variance estimators influence the meta-analysed IV estimate. Methods: Two versions of the delta method (IV before or after pooling), four bootstrap estimators, a jack-knife estimator and a heteroscedasticity-consistent (HC) variance estimator were compared using simulation. Two types of meta-analyses were compared, a two-stage meta-analysis pooling results, and a one-stage meta-analysis pooling datasets. Results: Using a two-stage meta-analysis, coverage of the point estimate using bootstrapped estimators deviated from nominal levels at weak instrument settings and/or outcome probabilities ≤ 0.10. The jack-knife estimator was the least biased resampling method, the HC estimator often failed at outcome probabilities ≤ 0.50 and overall the delta method estimators were the least biased. In the presence of between-study heterogeneity, the delta method before meta-analysis performed best. Using a one-stage meta-analysis all methods performed equally well and better than two-stage meta-analysis of greater or equal size. Conclusions: In the presence of between-study heterogeneity, two-stage meta-analyses should preferentially use the delta method before meta-analysis. Weak instrument bias can be reduced by performing a one-stage meta-analysis. PMID:27591262

Understanding the information needs of people with haematological cancers. A meta-ethnography of quantitative and qualitative research.

PubMed

Atherton, K; Young, B; Salmon, P

2017-11-01

Clinical practice in haematological oncology often involves difficult diagnostic and treatment decisions. In this context, understanding patients' information needs and the functions that information serves for them is particularly important. We systematically reviewed qualitative and quantitative evidence on haematological oncology patients' information needs to inform how these needs can best be addressed in clinical practice. PsycINFO, Medline and CINAHL Plus electronic databases were searched for relevant empirical papers published from January 2003 to July 2016. Synthesis of the findings drew on meta-ethnography and meta-study. Most quantitative studies used a survey design and indicated that patients are largely content with the information they receive from physicians, however much or little they actually receive, although a minority of patients are not content with information. Qualitative studies suggest that a sense of being in a caring relationship with a physician allows patients to feel content with the information they have been given, whereas patients who lack such a relationship want more information. The qualitative evidence can help explain the lack of association between the amount of information received and contentment with it in the quantitative research. Trusting relationships are integral to helping patients feel that their information needs have been met. © 2017 John Wiley & Sons Ltd.

Data extraction for complex meta-analysis (DECiMAL) guide.

PubMed

Pedder, Hugo; Sarri, Grammati; Keeney, Edna; Nunes, Vanessa; Dias, Sofia

2016-12-13

As more complex meta-analytical techniques such as network and multivariate meta-analyses become increasingly common, further pressures are placed on reviewers to extract data in a systematic and consistent manner. Failing to do this appropriately wastes time, resources and jeopardises accuracy. This guide (data extraction for complex meta-analysis (DECiMAL)) suggests a number of points to consider when collecting data, primarily aimed at systematic reviewers preparing data for meta-analysis. Network meta-analysis (NMA), multiple outcomes analysis and analysis combining different types of data are considered in a manner that can be useful across a range of data collection programmes. The guide has been shown to be both easy to learn and useful in a small pilot study.

Indirect health costs in ulcerative colitis and Crohn's disease: a systematic review and meta-analysis.

PubMed

Kawalec, Paweł; Malinowski, Krzysztof Piotr

2015-04-01

The aim of this systematic review was to collect all current data on indirect costs related to inflammatory bowel disease as well as assessing homogeneity and comparability, and conducting a meta-analysis. Costs were collected using databases from Medline, Embase and Centre for Reviews and Dissemination databases, then average annual cost per patient was calculated and expressed in 2013-rate USD using the consumer price index and purchasing power parity (scenario 1) and then adjusted to specific gross domestic product (scenario 2) to make them comparable. The studies were then included in quantitative synthesis using the meta-analysis and bootstrap methods. This systematic review was carried out and reported in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. From 18 publications, overall annual indirect costs per patient as a result of the quantitative synthesis among all studies eligible for meta-analysis ranged from US$2425.01-US$9622.15 depending on the scenario and model used for analysis. The cost of presenteeism was assessed in only two studies. Considering heterogeneity among all identified studies random-effect model presented the most accurate results of meta-analysis equal to US$7189.27 and US$9622.15 per patient per year for scenario 1 and scenario 2, respectively. This systematic review revealed the existence of a relatively small number of studies that reported on the great economic burden of the disease upon society. A great variety of methodologies and cost components resulted in a very large discrepancy in indirect costs and made meta-analysis difficult to perform, so two scenarios were considered and meta-analysis conducted in subgroups to make data more comparable.

Narcissism and Social Networking Behavior: A Meta-Analysis.

PubMed

Gnambs, Timo; Appel, Markus

2018-04-01

The increasing popularity of social networking sites (SNS) such as Facebook and Twitter has given rise to speculations that the intensity of using these platforms is associated with narcissistic tendencies. However, recent research on this issue has been all but conclusive. We present a three-level, random effects meta-analysis including 289 effect sizes from 57 studies (total N = 25,631) on the association between trait narcissism and social networking behavior. The meta-analysis identified a small to moderate effect of ρ = .17 (τ = .11), 95% CI [.13, .21], for grandiose narcissism that replicated across different social networking platforms, respondent characteristics, and time. Moderator analyses revealed pronounced cultural differences, with stronger associations in power-distant cultures. Moreover, social networking behaviors geared toward self-presentation and the number of SNS friends exhibited stronger effects than usage durations. Overall, the study not only supported but also refined the notion of a relationship between engaging in social networking sites and narcissistic personality traits. © 2017 Wiley Periodicals, Inc.

Protection from sunburn with beta-Carotene--a meta-analysis.

PubMed

Köpcke, Wolfgang; Krutmann, Jean

2008-01-01

Nutritional protection against skin damage from sunlight is increasingly advocated to the general public, but its effectiveness is controversial. In this meta-analysis, we have systematically reviewed the existing literature on human supplementation studies on dietary protection against sunburn by beta-carotene. A review of literature until June 2007 was performed in PubMed, ISI Web of Science and EBM Cochrane library and identified a total of seven studies which evaluated the effectiveness of beta-carotene in protection against sunburn. Data were abstracted from these studies by means of a standardized data collection protocol. The subsequent meta-analysis showed that (1) beta-carotene supplementation protects against sunburn and (2) the study duration had a significant influence on the effected size. Regression plot analysis revealed that protection required a minimum of 10 weeks of supplementation with a mean increase of the protective effect of 0.5 standard deviations with every additional month of supplementation. Thus, dietary supplementation of humans with beta-carotene provides protection against sunburn in a time-dependent manner.

Statistical Learning in Specific Language Impairment: A Meta-Analysis

ERIC Educational Resources Information Center

Lammertink, Imme; Boersma, Paul; Wijnen, Frank; Rispens, Judith

2017-01-01

Purpose: The current meta-analysis provides a quantitative overview of published and unpublished studies on statistical learning in the auditory verbal domain in people with and without specific language impairment (SLI). The database used for the meta-analysis is accessible online and open to updates (Community-Augmented Meta-Analysis), which…

Fall-Risk-Increasing Drugs: A Systematic Review and Meta-Analysis: I. Cardiovascular Drugs.

PubMed

de Vries, Max; Seppala, Lotta J; Daams, Joost G; van de Glind, Esther M M; Masud, Tahir; van der Velde, Nathalie

2018-04-01

Use of certain medications is recognized as a major and modifiable risk factor for falls. Although the literature on psychotropic drugs is compelling, the literature on cardiovascular drugs as potential fall-risk-increasing drugs is conflicting. The aim of this systematic review and meta-analysis is to provide a comprehensive overview of the associations between cardiovascular medications and fall risk in older adults. Design: A systematic review and meta-analysis. Medline, Embase, and PsycINFO. Key search concepts were "fall," "aged," "causality," and "medication." Studies that investigated cardiovascular medications as risk factors for falls in participants ≥60 years old or participants with a mean age of 70 or older were included. A meta-analysis was performed using the generic inverse variance method, pooling unadjusted and adjusted odds ratios (ORs) separately. In total, 131 studies were included in the qualitative synthesis. Meta-analysis using adjusted ORs showed significant results (pooled OR [95% confidence interval]) for loop diuretics, OR 1.36 (1.17, 1.57), and beta-blocking agents, OR 0.88 (0.80, 0.97). Meta-analysis using unadjusted ORs showed significant results for digitalis, OR 1.60 (1.08, 2.36); digoxin, OR 2.06 (1.56, 2.74); and statins, OR 0.80 (0.65, 0.98). Most of the meta-analyses resulted in substantial heterogeneity that mostly did not disappear after stratification for population and setting. In a descriptive synthesis, consistent associations were not observed. Loop diuretics were significantly associated with increased fall risk, whereas beta-blockers were significantly associated with decreased fall risk. Digitalis and digoxin may increase the risk of falling, and statins may reduce it. For the majority of cardiovascular medication groups, outcomes were inconsistent. Furthermore, recent studies indicate that specific drug properties, such as selectivity of beta-blockers, may affect fall risk, and drug-disease interaction also may play

A random effects meta-analysis model with Box-Cox transformation.

PubMed

Yamaguchi, Yusuke; Maruo, Kazushi; Partlett, Christopher; Riley, Richard D

2017-07-19

In a random effects meta-analysis model, true treatment effects for each study are routinely assumed to follow a normal distribution. However, normality is a restrictive assumption and the misspecification of the random effects distribution may result in a misleading estimate of overall mean for the treatment effect, an inappropriate quantification of heterogeneity across studies and a wrongly symmetric prediction interval. We focus on problems caused by an inappropriate normality assumption of the random effects distribution, and propose a novel random effects meta-analysis model where a Box-Cox transformation is applied to the observed treatment effect estimates. The proposed model aims to normalise an overall distribution of observed treatment effect estimates, which is sum of the within-study sampling distributions and the random effects distribution. When sampling distributions are approximately normal, non-normality in the overall distribution will be mainly due to the random effects distribution, especially when the between-study variation is large relative to the within-study variation. The Box-Cox transformation addresses this flexibly according to the observed departure from normality. We use a Bayesian approach for estimating parameters in the proposed model, and suggest summarising the meta-analysis results by an overall median, an interquartile range and a prediction interval. The model can be applied for any kind of variables once the treatment effect estimate is defined from the variable. A simulation study suggested that when the overall distribution of treatment effect estimates are skewed, the overall mean and conventional I 2 from the normal random effects model could be inappropriate summaries, and the proposed model helped reduce this issue. We illustrated the proposed model using two examples, which revealed some important differences on summary results, heterogeneity measures and prediction intervals from the normal random effects model. The

Meta-analysis in clinical trials revisited.

PubMed

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.

Meta-Analysis in Clinical Trials Revisited

PubMed Central

Laird, Nan

2015-01-01

In this paper, we revisit a 1986 article we published in this Journal, Meta-Analysis in Clinical Trials, where we introduced a random-effect 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. PMID:26343745

Conventional drilling versus piezosurgery for implant site preparation: a meta-analysis.

PubMed

Sendyk, Daniel Isaac; Oliveira, Natacha Kalline; Pannuti, Claudio Mendes; Naclério-Homem, Maria da Graça; Wennerberg, Ann; Zindel Deboni, Maria Cristina

2018-03-27

The aim of this study was to evaluate the evidence of a correlation between the stability of dental implants placed by piezosurgery, compared with implants placed by conventional drilling. An electronic search in MEDLINE, SCOPUS and the Cochrane Library was undertaken until August 2016 and was supplemented by manual searches and by unpublished studies at OpenGray. Only randomized controlled clinical trials that reported implant site preparation with piezosurgery and with conventional drilling were considered eligible for inclusion in this review. Meta-analyses were performed to evaluate the impact of piezosurgery on implant stability. Of 456 references electronically retrieved, 3 were included in the qualitative analysis and quantitative synthesis. The pooled estimates suggest that there is no significant difference between piezosurgery and conventional drilling at baseline (WMD: 2.20; 95% CI: -5.09, 9,49; p = 0.55). At 90 days, the pooled estimates revealed a statistically significant difference (WMD: 3.63; 95% CI: 0.58, 6.67, p = 0.02) favouring piezosurgery. Implant stability is slightly improved when osteotomy was performed by a piezoelectric device. More randomized controlled clinical trials are needed to verify these findings.

CTLA-4 polymorphisms and susceptibility to inflammatory bowel disease: a meta-analysis.

PubMed

Lee, Young Ho; Kim, Jae-Hoon; Seo, Young Ho; Choi, Sung Jae; Ji, Jong Dae; Song, Gwan Gyu

2014-05-01

The aim of this study was to explore whether the cytotoxic T lymphocyte associated antigen-4 (CTLA-4) polymorphisms are associated with susceptibility to ulcerative colitis (UC) and Crohn's disease (CD). The authors conducted a meta-analysis on associations between CTLA-4 +49 A/G, -318 C/T, CT60 A/G polymorphisms, and (AT)n repeat in the 3' untranslated region (UTR) and UC and CD susceptibility. A total of 15 comparison studies were considered in our meta-analysis. Meta-analysis revealed no association between UC and the CTLA-4 +49 G and CTLA-4 -318 T alleles in all subjects (OR=0.982, 95% CI=0.851-1.1339, p=0.804; OR=0.500, 95% CI=0.223-1.124, p=0.094). No association was found between UC and the CTLA-4 CT60 A/G polymorphism in Europeans. However, a significant association was observed between the longer allele (⩾118bp) of the (AT)n and UC in Asian population (OR=6.073, 95% CI=4.246-8.684, p=1.0×10(-9)). Meta-analysis of the CTLA-4 +49 A/G, -318 C/T, CT60 A/G polymorphisms showed no association with CD. This meta-analysis demonstrates that the CTLA-4 (AT)n repeat in 3' UTR may be associated with susceptibility to UC in Asians, while no association was found between the CTLA-4 +49 A/G, -318 C/T, and CD60 A/G polymorphism and susceptibility to UC and CD. Copyright © 2014 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

Evaluating the Quality of Evidence from a Network Meta-Analysis

PubMed Central

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

Serum S100B Is Related to Illness Duration and Clinical Symptoms in Schizophrenia—A Meta-Regression Analysis

PubMed Central

Schümberg, Katharina; Polyakova, Maryna; Steiner, Johann; Schroeter, Matthias L.

2016-01-01

S100B has been linked to glial pathology in several psychiatric disorders. Previous studies found higher S100B serum levels in patients with schizophrenia compared to healthy controls, and a number of covariates influencing the size of this effect have been proposed in the literature. Here, we conducted a meta-analysis and meta-regression analysis on alterations of serum S100B in schizophrenia in comparison with healthy control subjects. The meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement to guarantee a high quality and reproducibility. With strict inclusion criteria 19 original studies could be included in the quantitative meta-analysis, comprising a total of 766 patients and 607 healthy control subjects. The meta-analysis confirmed higher values of the glial serum marker S100B in schizophrenia if compared with control subjects. Meta-regression analyses revealed significant effects of illness duration and clinical symptomatology, in particular the total score of the Positive and Negative Syndrome Scale (PANSS), on serum S100B levels in schizophrenia. In sum, results confirm glial pathology in schizophrenia that is modulated by illness duration and related to clinical symptomatology. Further studies are needed to investigate mechanisms and mediating factors related to these findings. PMID:26941608

Random-effects meta-analysis: the number of studies matters.

PubMed

Guolo, Annamaria; Varin, Cristiano

2017-06-01

This paper investigates the impact of the number of studies on meta-analysis and meta-regression within the random-effects model framework. It is frequently neglected that inference in random-effects models requires a substantial number of studies included in meta-analysis to guarantee reliable conclusions. Several authors warn about the risk of inaccurate results of the traditional DerSimonian and Laird approach especially in the common case of meta-analysis involving a limited number of studies. This paper presents a selection of likelihood and non-likelihood methods for inference in meta-analysis proposed to overcome the limitations of the DerSimonian and Laird procedure, with a focus on the effect of the number of studies. The applicability and the performance of the methods are investigated in terms of Type I error rates and empirical power to detect effects, according to scenarios of practical interest. Simulation studies and applications to real meta-analyses highlight that it is not possible to identify an approach uniformly superior to alternatives. The overall recommendation is to avoid the DerSimonian and Laird method when the number of meta-analysis studies is modest and prefer a more comprehensive procedure that compares alternative inferential approaches. R code for meta-analysis according to all of the inferential methods examined in the paper is provided.

Multivariate meta-analysis: potential and promise.

PubMed

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

2011-09-10

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.

Cognitive-Based Interventions to Improve Mobility: A Systematic Review and Meta-analysis.

PubMed

Marusic, Uros; Verghese, Joe; Mahoney, Jeannette R

2018-06-01

A strong relation between cognition and mobility has been identified in aging, supporting a role for enhancement mobility through cognitive-based interventions. However, a critical evaluation of the consistency of treatment effects of cognitive-based interventions is currently lacking. The objective of this study was 2-fold: (1) to review the existing literature on cognitive-based interventions aimed at improving mobility in older adults and (2) to assess the clinical effectiveness of cognitive interventions on gait performance. A systematic review of randomized controlled trials (RCT) of cognitive training interventions for improving simple (normal walking) and complex (dual task walking) gait was conducted in February 2018. Older adults without major cognitive, psychiatric, neurologic, and/or sensory impairments were included. Random effect meta-analyses and a subsequent meta-regression were performed to generate overall cognitive intervention effects on single- and dual-task walking conditions. Ten RCTs met inclusion criteria, with a total of 351 participants included in this meta-analysis. Cognitive training interventions revealed a small effect of intervention on complex gait [effect size (ES) = 0.47, 95% confidence interval (CI) 0.13 to 0.81, P = .007, I 2  = 15.85%], but not simple gait (ES = 0.35, 95% CI -0.01 to 0.71, P = .057, I 2  = 57.32%). Moreover, a meta-regression analysis revealed that intervention duration, training frequency, total number of sessions, and total minutes spent in intervention were not significant predictors of improvement in dual-task walking speed, though there was a suggestive trend toward a negative association between dual-task walking speed improvements and individual training session duration (P = .067). This meta-analysis provides support for the fact that cognitive training interventions can improve mobility-related outcomes, especially during challenging walking conditions requiring higher-order executive

Systematic Review and Meta-Analysis of Studies Evaluating Diagnostic Test Accuracy: A Practical Review for Clinical Researchers-Part II. Statistical Methods of Meta-Analysis

PubMed Central

Lee, Juneyoung; Kim, Kyung Won; Choi, Sang Hyun; Huh, Jimi

2015-01-01

Meta-analysis of diagnostic test accuracy studies differs from the usual meta-analysis of therapeutic/interventional studies in that, it is required to simultaneously analyze a pair of two outcome measures such as sensitivity and specificity, instead of a single outcome. Since sensitivity and specificity are generally inversely correlated and could be affected by a threshold effect, more sophisticated statistical methods are required for the meta-analysis of diagnostic test accuracy. Hierarchical models including the bivariate model and the hierarchical summary receiver operating characteristic model are increasingly being accepted as standard methods for meta-analysis of diagnostic test accuracy studies. We provide a conceptual review of statistical methods currently used and recommended for meta-analysis of diagnostic test accuracy studies. This article could serve as a methodological reference for those who perform systematic review and meta-analysis of diagnostic test accuracy studies. PMID:26576107

Personality and Parkinson's disease: A meta-analysis.

PubMed

Santangelo, Gabriella; Garramone, Federica; Baiano, Chiara; D'Iorio, Alfonsina; Piscopo, Fausta; Raimo, Simona; Vitale, Carmine

2018-04-01

Personality changes are considered pre-motor features of Parkinson's disease (PD). Cross-sectional studies revealed that PD patients were more introvert, apprehensive, and cautious than healthy subjects (HS), whereas other studies failed to disclose these behavioural traits. Some studies found mixed results concerning Novelty Seeking (NS) and Harm Avoidance (HA) profiles in PD patients. To better clarify the personality profile in PD we performed a meta-analysis on studies exploring such topic according to both Cloninger's Psychobiological Model (PM) and Big Five Model (BFM) METHODS: The meta-analysis included 17 studies evaluating the personality in PD patients compared with HS. The outcomes were the dimensions of the temperament and character of the PM and personality traits of BFM. Effect sizes from data reported in the primary studies were computed using Hedges'g unbiased approach. Heterogeneity among the studies and publication bias were assessed. Meta-regressions were conducted with age at evaluation, gender, schooling, and type of personality trait tools as moderators. As for PM, PD patients scored higher on HA and lower on NS than HS. No difference was found on Reward Dependence, Perseverance/Persistence and on character level. As for BFM, higher levels of Neuroticism, but lower levels of Openness and Extraversion were associated with PD. The personality profile in PD is characterized by high Neuroticism and HA, and by low Openness, Extraversion and NS. The personality profile delineated in the present study on PD patients seems to reflect the premorbid one and might contribute to development and persistence of affective disorders. Copyright © 2018 Elsevier Ltd. All rights reserved.

Anxiety, depression, and health-related quality of life in heterozygous familial hypercholesterolemia: A systematic review and meta-analysis.

PubMed

Akioyamen, Leo E; Genest, Jacques; Shan, Shubham D; Inibhunu, Happy; Chu, Anna; Tu, Jack V

2018-06-01

Heterozygous familial hypercholesterolemia (FH) is a common genetic disease predisposing affected individuals to a high risk of cardiovascular disease. Yet, considerable uncertainty exists regarding its impact on psychosocial wellbeing. We performed a systematic review and meta-analysis of the association between FH and symptoms of anxiety and depression, and health-related quality of life (HRQL). We searched MEDLINE, EMBASE, Global Health, the Cochrane Library, PsycINFO, and PubMed for peer-reviewed literature published in English between January 1, 1990 and January 1, 2018. Quantitative and qualitative studies were eligible if they included patients with confirmed FH and evaluated its association with symptoms of anxiety or depression, or HRQL. We performed a narrative synthesis of studies, including thematic analysis of qualitative studies, and where data permitted, random-effects meta-analysis reporting standardized mean differences (SMD) and 95% confidence intervals. We found 10 eligible studies measuring HRQL, depression and anxiety. Random-effects meta-analysis of 4 (n = 4293) and 5 studies (n = 5098), respectively, showed that patients with FH had slightly lower symptoms of anxiety (SMD: -0.29 [95% CI: -0.53, -0.04]) and mental HRQL (SMD: -0.10 [95% -0.20, -0.00]) relative to general population controls. No significant differences existed in depressive symptoms (SMD: 0.04 [95% CI: -0.12, 0.19]) or physical HRQL scores (SMD: 0.02 [95% CI: -0.09, 0.12]). Our systematic review suggests that patients with FH may report small but measurable differences in anxiety symptoms and mental HRQL. Copyright © 2018 Elsevier Inc. All rights reserved.

A Meta-analysis Method to Advance Design of Technology-Based Learning Tool: Combining Qualitative and Quantitative Research to Understand Learning in Relation to Different Technology Features

NASA Astrophysics Data System (ADS)

Zhang, Lin

2014-02-01

Educators design and create various technology tools to scaffold students' learning. As more and more technology designs are incorporated into learning, growing attention has been paid to the study of technology-based learning tool. This paper discusses the emerging issues, such as how can learning effectiveness be understood in relation to different technology features? And how can pieces of qualitative and quantitative results be integrated to achieve a broader understanding of technology designs? To address these issues, this paper proposes a meta-analysis method. Detailed explanations about the structure of the methodology and its scientific mechanism are provided for discussions and suggestions. This paper ends with an in-depth discussion on the concerns and questions that educational researchers might raise, such as how this methodology takes care of learning contexts.

Proton-pump inhibitors and risk of fractures: an update meta-analysis.

PubMed

Zhou, B; Huang, Y; Li, H; Sun, W; Liu, J

2016-01-01

To identify the relationship between proton-pump inhibitors (PPIs) and the risk of fracture, we conducted an update meta-analysis of observational studies. Results showed that PPI use was associated with a modestly increased risk of hip, spine, and any-site fracture. Many studies have investigated the association of proton-pump inhibitors (PPIs) with fracture risk, but the results have been inconsistent. To evaluate this question, we performed a meta-analysis of relevant observational studies. A systematic literature search up to February 2015 was performed in PubMed. We combined relative risks (RRs) for fractures using random-effects models and conducted subgroup and stratified analyses. Eighteen studies involving a total of 244,109 fracture cases were included in this meta-analysis. Pooled analysis showed that PPI use could moderately increase the risk of hip fracture [RR = 1.26, 95 % confidence intervals (CIs) 1.16–1.36]. There was statistically significant heterogeneity among studies (p < 0.001; I 2 = 71.9 %). After limiting to cohort studies, there was also a moderate increase in hip fracture risk without evidence of study heterogeneity. Pooling revealed that short-term use (<1 year) and longer use (>1 year) were similarly associated with increased risk of hip fracture. Furthermore, a moderately increased risk of spine (RR = 1.58, 95 % CI 1.38–1.82) and any-site fracture (RR = 1.33, 95 % CI 1.15–1.54) was also found among PPI users. In this update meta-analysis of observational studies, PPI use modestly increased the risk of hip, spine, and any-site fracture, but no evidence of duration effect in subgroup analysis.

A meta-synthesis study of literature review and systematic review published in nurse prescribing

PubMed Central

Darvishpour, Azar; Joolaee, Soodabeh; Cheraghi, Mohammad Ali

2014-01-01

Background: Prescribing represents a new aspect of practice for nurses. To make qualitative results more accessible to clinicians, researchers, and policy makers, individuals are urged to synthesize findings from related studies. Therefore this study aimed to aggregate and interpret existing literature review and systematic studies to obtain new insights on nurse prescription. Methods: This was a qualitative meta synthesis study using Walsh and Downe process. In order to obtain data all Digital National Library of Medicine's databases, search engines and several related sites were used. Full texts with "review and nurs* prescri* " words in the title or abstract in English language and published without any time limitation were considered. After eliminating duplicate and irrelevant studies, 11 texts were selected. Data analysis was conducted using qualitative content analysis. Multiple codes were compared based on the differences and similarities and divided to the categories and themes. Results: The results from the meta synthesis of the 11 studies revealed 8 themes namely: leading countries in prescribing, views, features, infrastructures, benefits, disadvantages, facilitators and barriers of nursing prescription that are discussed in this article. The results led to a schematic model. Conclusion: Despite the positive view on nurse prescribing, there are still issues such as legal, administrative, weak research and educational deficiencies in academic preparation of nurses that needs more effort in these areas and requires further research. PMID:25405142

A meta-synthesis study of literature review and systematic review published in nurse prescribing.

PubMed

Darvishpour, Azar; Joolaee, Soodabeh; Cheraghi, Mohammad Ali

2014-01-01

Prescribing represents a new aspect of practice for nurses. To make qualitative results more accessible to clinicians, researchers, and policy makers, individuals are urged to synthesize findings from related studies. Therefore this study aimed to aggregate and interpret existing literature review and systematic studies to obtain new insights on nurse prescription. This was a qualitative meta synthesis study using Walsh and Downe process. In order to obtain data all Digital National Library of Medicine's databases, search engines and several related sites were used. Full texts with "review and nurs* prescri* " words in the title or abstract in English language and published without any time limitation were considered. After eliminating duplicate and irrelevant studies, 11 texts were selected. Data analysis was conducted using qualitative content analysis. Multiple codes were compared based on the differences and similarities and divided to the categories and themes. The results from the meta synthesis of the 11 studies revealed 8 themes namely: leading countries in prescribing, views, features, infrastructures, benefits, disadvantages, facilitators and barriers of nursing prescription that are discussed in this article. The results led to a schematic model. Despite the positive view on nurse prescribing, there are still issues such as legal, administrative, weak research and educational deficiencies in academic preparation of nurses that needs more effort in these areas and requires further research.

Using multiple group modeling to test moderators in meta-analysis.

PubMed

Schoemann, Alexander M

2016-12-01

Meta-analysis is a popular and flexible analysis that can be fit in many modeling frameworks. Two methods of fitting meta-analyses that are growing in popularity are structural equation modeling (SEM) and multilevel modeling (MLM). By using SEM or MLM to fit a meta-analysis researchers have access to powerful techniques associated with SEM and MLM. This paper details how to use one such technique, multiple group analysis, to test categorical moderators in meta-analysis. In a multiple group meta-analysis a model is fit to each level of the moderator simultaneously. By constraining parameters across groups any model parameter can be tested for equality. Using multiple groups to test for moderators is especially relevant in random-effects meta-analysis where both the mean and the between studies variance of the effect size may be compared across groups. A simulation study and the analysis of a real data set are used to illustrate multiple group modeling with both SEM and MLM. Issues related to multiple group meta-analysis and future directions for research are discussed. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Association between serum uric acid level and multiple system atrophy: A meta-analysis.

PubMed

Zhang, Xi; Liu, De-Shan; An, Chun-Yao; Liu, Yu-Zhao; Liu, Xiao-Hong; Zhang, Fang; Ning, Lu-Ning; Li, Chang-Ling; Ma, Chun-Mei; Hu, Rui-Ting

2018-06-01

Lower serum uric acid (UA) levels are considered to be related to the risk to develop many neurodegenerative disorders. However, the association between serum UA level and multiple system atrophy (MSA) remains controversial. The aim of this meta-analysis was to evaluate the relationship between serum UA level and MSA. PubMed, Web of Science, Embase, Cochrane Library and China National Knowledge Infrastructure (CNKI) were searched for eligible studies. Standardized mean difference (SMD) and 95% confidence intervals (95% CI) were calculated in a fixed-effects model or a random-effects model when appropriate. Subgroup analyses were carried out based on gender. A total of 6 eligible studies involving 547 MSA patients and 637 healthy individuals were identified. Meta-analysis results revealed that individuals with MSA had lower sera levels of UA as compared with healthy controls (pooled SMD is -0.51, 95%CI: -0.88 to -0.14; p = 0.006). The subgroup analysis to detect sex differences showed that the pooled SMD was -0.61 (95% CI: -0.82 to -0.40; p < 0.0001) for males and -0.22 (95% CI: -0.55 to 0.10; p = 0.18) for females compared with healthy controls. Our meta-analysis revealed that lower serum level of UA is associated with an increased risk of MSA and the relationship is significant in men but not in women. Copyright © 2018 Elsevier B.V. All rights reserved.

The effects of aromatherapy on sleep improvement: a systematic literature review and meta-analysis.

PubMed

Hwang, Eunhee; Shin, Sujin

2015-02-01

To evaluate the existing data on aromatherapy interventions for improvement of sleep quality. Systematic literature review and meta-analysis on the effects of aromatherapy. Study Sources: Electronic databases, including the Korea Education and Research Information Service (KERIS), Korean studies Information Service System (KISS), National Assembly Library, and eight academies within the Korean Society of Nursing Science, were searched to identify studies published between 2000 and August 2013. Randomized controlled and quasi-experimental trials that included aromatherapy for the improvement of sleep quality. Of the 245 publications identified, 13 studies met the inclusion and exclusion criteria, and 12 studies were used in the meta-analysis. Meta-analysis of the 12 studies using a random-effects model revealed that the use of aromatherapy was effective in improving sleep quality (95% confidence interval [CI], 0.540-1.745; Z=3.716). Subgroup analysis revealed that inhalation aromatherapy (95% CI, 0.792-1.541; Z=6.107) was more effective than massage therapy (95% CI, 0.128-2.166; Z=2.205) in unhealthy (95% CI, 0.248-1.100; Z=3.100) and healthy (95% CI, 0.393-5.104; Z=2.287) participants, respectively. Readily available aromatherapy treatments appear to be effective and promote sleep. Thus, it is essential to develop specific guidelines for the efficient use of aromatherapy.

Drivers of Wetland Conversion: a Global Meta-Analysis

PubMed Central

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

Drivers of wetland conversion: a global meta-analysis.

PubMed

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

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

PubMed

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 <65 years than for those aged ≥65 years, and higher for men than for women. According to the results of stratified 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.

Conducting Qualitative Data Analysis: Qualitative Data Analysis as a Metaphoric Process

ERIC Educational Resources Information Center

Chenail, Ronald J.

2012-01-01

In the second of a series of "how-to" essays on conducting qualitative data analysis, Ron Chenail argues the process can best be understood as a metaphoric process. From this orientation he suggests researchers follow Kenneth Burke's notion of metaphor and see qualitative data analysis as the analyst systematically considering the "this-ness" of…

Factors associated with community reintegration in the first year after stroke: a qualitative meta-synthesis.

PubMed

Walsh, Mary E; Galvin, Rose; Loughnane, Cliona; Macey, Chris; Horgan, N Frances

2015-01-01

Although acute stroke care has improved survival, many individuals report dissatisfaction with community reintegration after stroke. The aim of this qualitative meta-synthesis was to examine the barriers and facilitators of community reintegration in the first year after stroke from the perspective of people with stroke. A systematic literature search was conducted. Papers that used qualitative methods to explore the experiences of individuals with stroke around community reintegration in the first year after stroke were included. Two reviewers independently assessed the methodological quality of papers. Themes, concepts and interpretations were extracted from each study, compared and meta-synthesised. From the 18 included qualitative studies four themes related to community reintegration in the first year after stroke were identified: (i) the primary effects of stroke, (ii) personal factors, (iii) social factors and (iv) relationships with professionals. This review suggests that an individual's perseverance, adaptability and ability to overcome emotional challenges can facilitate reintegration into the community despite persisting effects of their stroke. Appropriate support from family, friends, the broader community and healthcare professionals is important. Therapeutic activities should relate to meaningful activities and should be tailored to the individual stroke survivor. Stroke survivors feel that rehabilitation in familiar environments and therapeutic activities that reflect real-life could help their community re-integration. In addition to the physical sequelae of stroke, emotional consequences of stroke should be addressed during rehabilitation. Healthcare professionals can provide clear and locally relevant advice to facilitate aspects of community reintegration, including the return to driving and work.

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

PubMed

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.

Adjunctive minocycline for schizophrenia: A meta-analysis of randomized controlled trials.

PubMed

Xiang, Ying-Qiang; Zheng, Wei; Wang, Shi-Bin; Yang, Xin-Hu; Cai, Dong-Bin; Ng, Chee H; Ungvari, Gabor S; Kelly, Deanna L; Xu, Wei-Ying; Xiang, Yu-Tao

2017-01-01

This study aimed to conduct a meta-analysis of the efficacy and safety of adjunctive minocycline for schizophrenia. Randomized controlled trials (RCTs) comparing adjunctive minocycline with placebo in patients with schizophrenia were included in the meta-analysis. Two independent investigators extracted and synthesized data. Standard mean differences (SMDs), risk ratio (RR) ±95% confidence intervals (CIs) and the number-needed-to-harm (NNH) were calculated. Eight RCTs with 548 schizophrenia patient including 286 (52.2%) patients on minocycline (171.9±31.2mg/day) and 262 (47.8%) on placebo completed 18.5±13.4 weeks of treatment. Meta-analyses of Positive and Negative Syndrome Scale (PANSS) (7 RCTs with 8 treatment arms)/Brief Psychiatric Rating Scale (BPRS) (1 RCT) total score [SMD: -0.64, (95%CI: -1.02, -0.27), P=0.0008; I 2 =74%], positive, negative and general symptom scores [SMD: -0.69 to -0.22 (95%CI: -0.98, -0.03), P=0.02-0.00001; I 2 =7-63%] revealed a significant superiority of adjunctive minocycline treatment over the placebo. There was no significant difference regarding neurocognitive function, discontinuation rate and adverse drug reactions between the two groups. This meta-analysis showed that adjunctive minocycline appears to be efficacious and safe for schizophrenia. Due to significant heterogeneity, future studies with a large sample size are needed to confirm these findings. Copyright © 2016 Elsevier B.V. and ECNP. All rights reserved.

Delayed reward discounting and addictive behavior: a meta-analysis.

PubMed

MacKillop, James; Amlung, Michael T; Few, Lauren R; Ray, Lara A; Sweet, Lawrence H; Munafò, Marcus R

2011-08-01

Delayed reward discounting (DRD) is a behavioral economic index of impulsivity and numerous studies have examined DRD in relation to addictive behavior. To synthesize the findings across the literature, the current review is a meta-analysis of studies comparing DRD between criterion groups exhibiting addictive behavior and control groups. The meta-analysis sought to characterize the overall patterns of findings, systematic variability by sample and study type, and possible small study (publication) bias. Literature reviews identified 310 candidate articles from which 46 studies reporting 64 comparisons were identified (total N=56,013). From the total comparisons identified, a small magnitude effect was evident (d= .15; p< .00001) with very high heterogeneity of effect size. Based on systematic observed differences, large studies assessing DRD with a small number of self-report items were removed and an analysis of 57 comparisons (n=3,329) using equivalent methods and exhibiting acceptable heterogeneity revealed a medium magnitude effect (d= .58; p< .00001). Further analyses revealed significantly larger effect sizes for studies using clinical samples (d= .61) compared with studies using nonclinical samples (d=.45). Indices of small study bias among the various comparisons suggested varying levels of influence by unpublished findings, ranging from minimal to moderate. These results provide strong evidence of greater DRD in individuals exhibiting addictive behavior in general and particularly in individuals who meet criteria for an addictive disorder. Implications for the assessment of DRD and research priorities are discussed.

Delayed reward discounting and addictive behavior: a meta-analysis

PubMed Central

Amlung, Michael T.; Few, Lauren R.; Ray, Lara A.; Sweet, Lawrence H.; Munafò, Marcus R.

2011-01-01

Rationale Delayed reward discounting (DRD) is a behavioral economic index of impulsivity and numerous studies have examined DRD in relation to addictive behavior. To synthesize the findings across the literature, the current review is a meta-analysis of studies comparing DRD between criterion groups exhibiting addictive behavior and control groups. Objectives The meta-analysis sought to characterize the overall patterns of findings, systematic variability by sample and study type, and possible small study (publication) bias. Methods Literature reviews identified 310 candidate articles from which 46 studies reporting 64 comparisons were identified (total N=56,013). Results From the total comparisons identified, a small magnitude effect was evident (d=.15; p<.00001) with very high heterogeneity of effect size. Based on systematic observed differences, large studies assessing DRD with a small number of self-report items were removed and an analysis of 57 comparisons (n=3,329) using equivalent methods and exhibiting acceptable heterogeneity revealed a medium magnitude effect (d=.58; p<.00001). Further analyses revealed significantly larger effect sizes for studies using clinical samples (d=.61) compared with studies using nonclinical samples (d=.45). Indices of small study bias among the various comparisons suggested varying levels of influence by unpublished findings, ranging from minimal to moderate. Conclusions These results provide strong evidence of greater DRD in individuals exhibiting addictive behavior in general and particularly in individuals who meet criteria for an addictive disorder. Implications for the assessment of DRD and research priorities are discussed. PMID:21373791

Multivariate meta-analysis with an increasing number of parameters

PubMed Central

Boca, Simina M.; Pfeiffer, Ruth M.; Sampson, Joshua N.

2017-01-01

Summary Meta-analysis can average estimates of multiple parameters, such as a treatment’s effect on multiple outcomes, across studies. Univariate meta-analysis (UVMA) considers each parameter individually, while multivariate meta-analysis (MVMA) considers the parameters jointly and accounts for the correlation between their estimates. The performance of MVMA and UVMA has been extensively compared in scenarios with two parameters. Our objective is to compare the performance of MVMA and UVMA as the number of parameters, p, increases. Specifically, we show that (i) for fixed-effect meta-analysis, the benefit from using MVMA can substantially increase as p increases; (ii) for random effects meta-analysis, the benefit from MVMA can increase as p increases, but the potential improvement is modest in the presence of high between-study variability and the actual improvement is further reduced by the need to estimate an increasingly large between study covariance matrix; and (iii) when there is little to no between study variability, the loss of efficiency due to choosing random effects MVMA over fixed-effect MVMA increases as p increases. We demonstrate these three features through theory, simulation, and a meta-analysis of risk factors for Non-Hodgkin Lymphoma. PMID:28195655

Biological risk factors for suicidal behaviors: a meta-analysis

PubMed Central

Chang, B P; Franklin, J C; Ribeiro, J D; Fox, K R; Bentley, K H; Kleiman, E M; Nock, M K

2016-01-01

Prior studies have proposed a wide range of potential biological risk factors for future suicidal behaviors. Although strong evidence exists for biological correlates of suicidal behaviors, it remains unclear if these correlates are also risk factors for suicidal behaviors. We performed a meta-analysis to integrate the existing literature on biological risk factors for suicidal behaviors and to determine their statistical significance. We conducted a systematic search of PubMed, PsycInfo and Google Scholar for studies that used a biological factor to predict either suicide attempt or death by suicide. Inclusion criteria included studies with at least one longitudinal analysis using a biological factor to predict either of these outcomes in any population through 2015. From an initial screen of 2541 studies we identified 94 cases. Random effects models were used for both meta-analyses and meta-regression. The combined effect of biological factors produced statistically significant but relatively weak prediction of suicide attempts (weighted mean odds ratio (wOR)=1.41; CI: 1.09–1.81) and suicide death (wOR=1.28; CI: 1.13–1.45). After accounting for publication bias, prediction was nonsignificant for both suicide attempts and suicide death. Only two factors remained significant after accounting for publication bias—cytokines (wOR=2.87; CI: 1.40–5.93) and low levels of fish oil nutrients (wOR=1.09; CI: 1.01–1.19). Our meta-analysis revealed that currently known biological factors are weak predictors of future suicidal behaviors. This conclusion should be interpreted within the context of the limitations of the existing literature, including long follow-up intervals and a lack of tests of interactions with other risk factors. Future studies addressing these limitations may more effectively test for potential biological risk factors. PMID:27622931

Steep delay discounting and addictive behavior: a meta-analysis of continuous associations.

PubMed

Amlung, Michael; Vedelago, Lana; Acker, John; Balodis, Iris; MacKillop, James

2017-01-01

To synthesize continuous associations between delayed reward discounting (DRD) and both addiction severity and quantity-frequency (QF); to examine moderators of these relationships; and to investigate publication bias. Meta-analysis of published studies examining continuous associations between DRD and addictive behaviors. Published, peer-reviewed studies on addictive behaviors (alcohol, tobacco, cannabis, stimulants, opiates and gambling) were identified via PubMed, MEDLINE and PsycInfo. Studies were restricted to DRD measures of monetary gains. Random-effects meta-analysis was conducted using Pearson's r as the effect size. Publication bias was evaluated using fail-safe N, Begg-Mazumdar and Egger's tests, meta-regression of publication year and effect size and imputation of missing studies. The primary meta-analysis revealed a small magnitude effect size that was highly significant (r = 0.14, P < 10 -14 ). Significantly larger effect sizes were observed for studies examining severity compared with QF (P = 0.01), but not between the type of addictive behavior (P = 0.30) or DRD assessment (P = 0.90). Indices of publication bias suggested a modest impact of unpublished findings. Delayed reward discounting is associated robustly with continuous measures of addiction severity and quantity-frequency. This relation is generally robust across type of addictive behavior and delayed reward discounting assessment modality. © 2016 Society for the Study of Addiction.

Steep Delay Discounting and Addictive Behavior: A Meta-Analysis of Continuous Associations

PubMed Central

Amlung, Michael; Vedelago, Lana; Acker, John; Balodis, Iris; MacKillop, James

2016-01-01

Aims To synthesize continuous associations between delayed reward discounting (DRD) and both addiction severity and quantity-frequency (QF); to examine moderators of these relationships; and to investigate publication bias. Methods Meta-analysis of published studies examining continuous associations between DRD and addictive behaviors. Published, peer-reviewed studies on addictive behaviors (alcohol, tobacco, cannabis, stimulants, opiates, and gambling) were identified via PubMed, MEDLINE, and PsycInfo. Studies were restricted to DRD measures of monetary gains. Random effects meta-analysis was conducted using Pearson’s r as the effect size. Publication bias was evaluated using fail-safe N, Begg-Mazumdar and Egger’s tests, meta-regression of publication year and effect size, and imputation of missing studies. Results The primary meta-analysis revealed a small magnitude effect size that was highly significant (r = 0.14, p < 10−14). Significantly larger effect sizes were observed for studies examining severity compared with QF (p = 0.01), but not between the type of addictive behavior (p = 0.30) or DRD assessment (p = 0.90). Indices of publication bias suggested a modest impact of unpublished findings. Conclusions Delayed reward discounting is robustly associated with continuous measures of addiction severity and quantity-frequency. This relation is generally robust across type of addictive behavior and delayed reward discounting assessment modality. PMID:27450931

Integration of Research Studies: Meta-Analysis of Research. Methods of Integrative Analysis; Final Report.

ERIC Educational Resources Information Center

Glass, Gene V.; And Others

Integrative analysis, or what is coming to be known as meta-analysis, is the integration of the findings of many empirical research studies of a topic. Meta-analysis differs from traditional narrative forms of research reviewing in that it is more quantitative and statistical. Thus, the methods of meta-analysis are merely statistical methods,…

Multivariate meta-analysis: Potential and promise

PubMed Central

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

The Relationship between Serum Lipids and Sudden Sensorineural Hearing Loss: A Systematic Review and Meta-Analysis

PubMed Central

Chang, I Jen; Kang, Chung Jan; Yueh, Chen Yu; Fang, Ku Hao; Yeh, Re Ming; Tsai, Yao Te

2015-01-01

Background Sudden sensorineural hearing loss (SSNHL) is a relatively common condition that is usually of unknown etiology. A number of individual studies have investigated the association between various serum lipids and SSNHL; however, the findings have been inconsistent. In an attempt to obtain more definitive information on the relationship between serum lipids and SSNHL, we carried out a systematic review and meta-analysis. Methods Medline, the Cochrane Library, and EMBASE were searched using the following key words: lipid, cholesterol, triglyceride, fat, serum, blood, sudden hearing loss, hearing loss, hearing disorders. Randomized controlled trials, prospective cohort studies, and retrospective case-control studies involving patients with SSNHL and healthy controls that examined the relationship (reported as odds ratios [OR]) between lipid profiles and SSNHL were included. Primary outcomes were total cholesterol and low-density lipoprotein cholesterol (LDL-C) concentrations. Secondary outcomes were triglyceride, high-density lipoprotein cholesterol, and lipoprotein(a) concentrations. Results A total of 6 case-control studies were included in this systematic review/meta-analysis. The total number of participants ranged from 30 to 250 in the case group and from 43 to 271 in the control group. Meta-analysis revealed no significant difference in total cholesterol levels between the case and control groups (pooled OR = 1.79, 95% confidence interval [CI] = 0.98 to 3.26, P = 0.057). Likewise, meta-analysis revealed no significant difference in LDL-C concentrations between the case and control groups (pooled OR = 1.15, 95% CI = 0.64 to 2.07, P = 0.639). Since there were an insufficient number of studies reporting data for the secondary outcomes, meta-analysis was not possible. Conclusions Our results do not provide evidence for serum lipids being associated with SSNHL, nor do they definitively rule out such an association. Additional studies are needed to ascertain

Hypothyroidism as a risk factor for open angle glaucoma: A systematic review and meta-analysis

PubMed Central

Liu, Yue; Zheng, Guangying

2017-01-01

Purpose The relationship between hypothyroidism and primary open angle glaucoma (POAG) has attracted intense interest recently, but the reported results have been controversial. This meta-analysis was carried out to determine the association between hypothyroidism and POAG. Methods The literature was identified from three databases (Web of Science, Embase, and PubMed). The meta-analyses were performed using random-effects models, with results reported as adjusted odds ratios (ORs) with 95% confidence intervals (CI 95%). Results A total of 11 studies meeting the inclusion criteria were included in the final meta-analysis. The pooled OR based on 11 risk estimates showed a statistically significant increased risk of POAG prevalence among individuals with hypothyroidism (OR = 1.64, 95% CI = 1.27–2.13). Substantial heterogeneity among these studies was detected (P < 0.001; I2 = 83.2%). Sub-group analysis revealed that the cohort studies and case–control studies showed a significant association between hypothyroidism and POAG, which was not observed in cross-sectional studies. There was no significant publication bias in this study. Conclusions The findings of this meta-analysis indicate that individuals with hypothyroidism have an increased risk of developing POAG. PMID:29069095

Describing qualitative research undertaken with randomised controlled trials in grant proposals: a documentary analysis.

PubMed

Drabble, Sarah J; O'Cathain, Alicia; Thomas, Kate J; Rudolph, Anne; Hewison, Jenny

2014-02-18

There is growing recognition of the value of conducting qualitative research with trials in health research. It is timely to reflect on how this qualitative research is presented in grant proposals to identify lessons for researchers and research commissioners. As part of a larger study focusing on how to maximise the value of undertaking qualitative research with trials, we undertook a documentary analysis of proposals of funded studies. Using the metaRegister of Controlled Trials (mRCT) database we identified trials funded in the United Kingdom, ongoing between 2001 and 2010, and reporting the use of qualitative research. We requested copies of proposals from lead researchers. We extracted data from the proposals using closed and open questions, analysed using descriptive statistics and content analysis respectively. 2% (89/3812) of trials in the mRCT database described the use of qualitative research undertaken with the trial. From these 89 trials, we received copies of 36 full proposals, of which 32 met our inclusion criteria. 25% used less than a single paragraph to describe the qualitative research. The aims of the qualitative research described in these proposals focused mainly on the intervention or trial conduct. Just over half (56%) of the proposals included an explicit rationale for conducting the qualitative research with the trial, the most frequent being to optimise implementation into clinical practice or to interpret trial findings. Key information about methods, expertise and resources was missing in a large minority of proposals, in particular sample size, type of analysis, and non-personnel resources. 28% specifically stated that qualitative researchers would conduct the qualitative research. Our review of proposals of successfully funded studies identified good practice but also identified limited space given to describing the qualitative research, with an associated lack of attention to the rationale for doing the qualitative research and

Diagnostic significance of microRNAs as novel biomarkers for bladder cancer: a meta-analysis of ten articles.

PubMed

Shi, Hong-Bin; Yu, Jia-Xing; Yu, Jian-Xiu; Feng, Zheng; Zhang, Chao; Li, Guang-Yong; Zhao, Rui-Ning; Yang, Xiao-Bo

2017-08-03

Previous studies have revealed the importance of microRNAs' (miRNAs) function as biomarkers in diagnosing human bladder cancer (BC). However, the results are discordant. Consequently, the possibility of miRNAs to be BC biomarkers was summarized in this meta-analysis. In this study, the relevant articles were systematically searched from CBM, PubMed, EMBASE, and Chinese National Knowledge Infrastructure (CNKI). The bivariate model was used to calculate the pooled diagnostic parameters and summary receiver operator characteristic (SROC) curve in this meta-analysis, thereby estimating the whole predictive performance. STATA software was used during the whole analysis. Thirty-one studies from 10 articles, including 1556 cases and 1347 controls, were explored in this meta-analysis. In short, the pooled sensitivity, area under the SROC curve, specificity, positive likelihood ratio, diagnostic odds ratio, and negative likelihood ratio were 0.72 (95%CI 0.66-0.76), 0.80 (0.77-0.84), 0.76 (0.71-0.81), 3.0 (2.4-3.8), 8 (5.0-12.0), and 0.37 (0.30-0.46) respectively. Additionally, sub-group and meta-regression analyses revealed that there were significant differences between ethnicity, miRNA profiling, and specimen sub-groups. These results suggested that Asian population-based studies, multiple-miRNA profiling, and blood-based assays might yield a higher diagnostic accuracy than their counterparts. This meta-analysis demonstrated that miRNAs, particularly multiple miRNAs in the blood, might be novel, useful biomarkers with relatively high sensitivity and specificity and can be used for the diagnosis of BC. However, further prospective studies with more samples should be performed for further validation.

Comparing Effects of Different Applications on Pre-Service Teachers: A Meta-Analysis

ERIC Educational Resources Information Center

Elaldi, Senel; Batdi, Veli

2016-01-01

This study attempts to reveal whether different applications have effects on retention and attitude of pre-service teachers studying in various branches in Turkey through meta-analysis. Studies carried out between 2005 and 2015 in national and international area, 324 (218 articles, 106 theses) were chosen. However, 23 studies (9 retention and 14…

Automatic imitation: A meta-analysis.

PubMed

Cracco, Emiel; Bardi, Lara; Desmet, Charlotte; Genschow, Oliver; Rigoni, Davide; De Coster, Lize; Radkova, Ina; Deschrijver, Eliane; Brass, Marcel

2018-05-01

Automatic imitation is the finding that movement execution is facilitated by compatible and impeded by incompatible observed movements. In the past 15 years, automatic imitation has been studied to understand the relation between perception and action in social interaction. Although research on this topic started in cognitive science, interest quickly spread to related disciplines such as social psychology, clinical psychology, and neuroscience. However, important theoretical questions have remained unanswered. Therefore, in the present meta-analysis, we evaluated seven key questions on automatic imitation. The results, based on 161 studies containing 226 experiments, revealed an overall effect size of g z = 0.95, 95% CI [0.88, 1.02]. Moderator analyses identified automatic imitation as a flexible, largely automatic process that is driven by movement and effector compatibility, but is also influenced by spatial compatibility. Automatic imitation was found to be stronger for forced choice tasks than for simple response tasks, for human agents than for nonhuman agents, and for goalless actions than for goal-directed actions. However, it was not modulated by more subtle factors such as animacy beliefs, motion profiles, or visual perspective. Finally, there was no evidence for a relation between automatic imitation and either empathy or autism. Among other things, these findings point toward actor-imitator similarity as a crucial modulator of automatic imitation and challenge the view that imitative tendencies are an indicator of social functioning. The current meta-analysis has important theoretical implications and sheds light on longstanding controversies in the literature on automatic imitation and related domains. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Problems and Issues in Meta-Analysis.

ERIC Educational Resources Information Center

George, Carrie A.

Single studies, by themselves, rarely explain the effect of treatments or interventions definitively in the social sciences. Researchers created meta-analysis in the 1970s to address this need. Since then, meta-analytic techniques have been used to support certain treatment modalities and to influence policymakers. Although these techniques…

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

PubMed

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.

The effectiveness of oral appliances for obstructive sleep apnea syndrome: A meta-analysis.

PubMed

Zhu, Yafen; Long, Hu; Jian, Fan; Lin, Jianchang; Zhu, Jingyi; Gao, Meiya; Lai, Wenli

2015-12-01

To evaluate the effectiveness of oral appliances (OAs) for managing patients with obstructive sleep apnea (OSA). PubMed, Embase, Web of Science, CENTRAL and SIGLE were electronically searched from January 1980 to September 2015 for randomized or nonrandomized controlled trials that assessed the effectiveness of OAs on OSAS. The processes of study search, selection, data extraction, assessment of risk of bias and evaluation of evidence quality were conducted independently by two reviewer authors. Meta-analyses were performed in Review Manager 5, Stata11.0 and StatsDirect 2.7.9. Finally, we included 17 eligible studies which compared OAs and placebo or blank control. Six outcomes were assessed in this meta-analysis, i.e., apnea hypopnea index (AHI), respiratory arousal index (RAI), minimum oxygen saturation(MinSaO2), rapid eye movement (REM) sleep, sleep efficiency and Epworth Sleepiness Scale (ESS). Meta-analysis revealed that the pooled mean differences were -10.26 [95% CI: (-12.59, -7.93)], -9.03 [95% CI: (-11.89, -6.17)], 3.08 [95% CI: (1.97, 4.19)], 0.36 [95% CI: (-0.30, 1.02)], 1.34 [95% CI: (-0.05, 2.73)] and -1.76 [95% CI: (-2.57, -0.94)], respectively. The sensitivity analysis and subgroup analysis displayed generally robust results except for MinSaO2, REM sleep and sleep efficiency. Furthermore, publication bias was detected in RAI and MinSaO2. The available evidence indicates benefits in respiration and sleep quality with oral appliances as compared to placebo devices or blank control, while we cannot determine its effectiveness in sleep efficiency and sleep architecture alterations. However, due to low evidence quality as revealed by GRADE, this finding should be interpreted with caution. Through critical meta-analyses, we found that oral appliances are effective in respiration improving and sleep quality. The existing evidence supports the employment of OAs as a recommendable treatment option for OSA. This meta-analysis helps to direct clinical practice

Affective outcomes of virtual reality exposure therapy for anxiety and specific phobias: a meta-analysis.

PubMed

Parsons, Thomas D; Rizzo, Albert A

2008-09-01

Virtual reality exposure therapy (VRET) is an increasingly common treatment for anxiety and specific phobias. Lacking is a quantitative meta-analysis that enhances understanding of the variability and clinical significance of anxiety reduction outcomes after VRET. Searches of electronic databases yielded 52 studies, and of these, 21 studies (300 subjects) met inclusion criteria. Although meta-analysis revealed large declines in anxiety symptoms following VRET, moderator analyses were limited due to inconsistent reporting in the VRET literature. This highlights the need for future research studies that report uniform and detailed information regarding presence, immersion, anxiety and/or phobia duration, and demographics.

Air ions and mood outcomes: a review and meta-analysis

PubMed Central

2013-01-01

Background Psychological effects of air ions have been reported for more than 80 years in the media and scientific literature. This study summarizes a qualitative literature review and quantitative meta-analysis, where applicable, that examines the potential effects of exposure to negative and positive air ions on psychological measures of mood and emotional state. Methods A structured literature review was conducted to identify human experimental studies published through August, 2012. Thirty-three studies (1957–2012) evaluating the effects of air ionization on depression, anxiety, mood states, and subjective feelings of mental well-being in humans were included. Five studies on negative ionization and depression (measured using a structured interview guide) were evaluated by level of exposure intensity (high vs. low) using meta-analysis. Results Consistent ionization effects were not observed for anxiety, mood, relaxation/sleep, and personal comfort. In contrast, meta-analysis results showed that negative ionization, overall, was significantly associated with lower depression ratings, with a stronger association observed at high levels of negative ion exposure (mean summary effect and 95% confidence interval (CI) following high- and low-density exposure: 14.28 (95% CI: 12.93-15.62) and 7.23 (95% CI: 2.62-11.83), respectively). The response to high-density ionization was observed in patients with seasonal or chronic depression, but an effect of low-density ionization was observed only in patients with seasonal depression. However, no relationship between the duration or frequency of ionization treatment on depression ratings was evident. Conclusions No consistent influence of positive or negative air ionization on anxiety, mood, relaxation, sleep, and personal comfort measures was observed. Negative air ionization was associated with lower depression scores particularly at the highest exposure level. Future research is needed to evaluate the biological

Genetic Polymorphisms of Glutathione-Related Enzymes (GSTM1, GSTT1, and GSTP1) and Schizophrenia Risk: A Meta-Analysis

PubMed Central

Kim, Su Kang; Kang, Sang Wook; Chung, Joo-Ho; Park, Hae Jeong; Cho, Kyu Bong; Park, Min-Su

2015-01-01

The association between polymorphisms of glutathione-related enzyme (GST) genes and the risk of schizophrenia has been investigated in many published studies. However, their results were inconclusive. Therefore, we performed a meta-analysis to explore the association between the GSTM1, GSTT1, and GSTP1 polymorphisms and the risk of schizophrenia. Twelve case-control studies were included in this meta-analysis. The odds ratio (OR) and 95% confidence interval (95% CI) were used to investigate the strength of the association. Our meta-analysis results revealed that GSTM1, GSTT1, and GSTP1 polymorphisms were not related to risk of schizophrenia (p > 0.05 in each model). Further analyses based on ethnicity, GSTM polymorphism showed weak association with schizophrenia in East Asian population (OR = 1.314, 95% CI = 1.025–1.684, p = 0.031). In conclusion, our meta-analysis indicated the GSTM1 polymorphism may be the only genetic risk factor for schizophrenia in East Asian population. However, more meta-analysis with a larger sample size were needed to provide more precise evidence. PMID:26295386

Neurocognitive effects of methylphenidate in adults with attention-deficit/hyperactivity disorder: A meta-analysis.

PubMed

Pievsky, Michelle A; McGrath, Robert E

2018-05-08

PIEVSKY, M. A., and R. E. McGrath. Neurocognitive effects of methylphenidate in adults with attention-deficit/hyperactivity disorder: A meta-analysis…NEUROSCI BIOBEHAV REV 81(1) XXX-XXX, 2017.- This meta-analysis summarized 21 double-blind randomized controlled trials with a mean study duration of 18 days comparing the neurocognitive functioning of adults with attention-deficit/hyperactivity disorder (ADHD) on methylphenidate vs placebo. Effect sizes were weighted using a random-effects model. Scores on neurocognitive measures and tests of driving ability were on average higher on methylphenidate than on placebo, g = 0.17, p < .01, 95% CI = [0.05, 0.28], with little heterogeneity, Q(20) = 15.05, p = .77, I 2  = 0. Performance on methylphenidate was significantly better than on placebo for the following domains: working memory (mean g = 0.13, 95% CI = [0.00, 0.26]), reaction time variability (0.16, [0.03, 0.28]), vigilance (0.22, [0.11, 0.33]), driving (0.22, [0.10, 0.34]), and response inhibition (0.23, [0.10, 0.36]). Quantitative and qualitative assessment revealed evidence of publication bias. Summarizing across studies, methylphenidate improved the performance of adults with ADHD on neurocognitive measures and tests of driving, suggesting that methylphenidate is an effective treatment for adults with ADHD and can improve processes related to attention and concentration. Copyright © 2018 Elsevier Ltd. All rights reserved.

A methodological systematic review of what's wrong with meta-ethnography reporting.

PubMed

France, Emma F; Ring, Nicola; Thomas, Rebecca; Noyes, Jane; Maxwell, Margaret; Jepson, Ruth

2014-11-19

Syntheses of qualitative studies can inform health policy, services and our understanding of patient experience. Meta-ethnography is a systematic seven-phase interpretive qualitative synthesis approach well-suited to producing new theories and conceptual models. However, there are concerns about the quality of meta-ethnography reporting, particularly the analysis and synthesis processes. Our aim was to investigate the application and reporting of methods in recent meta-ethnography journal papers, focusing on the analysis and synthesis process and output. Methodological systematic review of health-related meta-ethnography journal papers published from 2012-2013. We searched six electronic databases, Google Scholar and Zetoc for papers using key terms including 'meta-ethnography.' Two authors independently screened papers by title and abstract with 100% agreement. We identified 32 relevant papers. Three authors independently extracted data and all authors analysed the application and reporting of methods using content analysis. Meta-ethnography was applied in diverse ways, sometimes inappropriately. In 13% of papers the approach did not suit the research aim. In 66% of papers reviewers did not follow the principles of meta-ethnography. The analytical and synthesis processes were poorly reported overall. In only 31% of papers reviewers clearly described how they analysed conceptual data from primary studies (phase 5, 'translation' of studies) and in only one paper (3%) reviewers explicitly described how they conducted the analytic synthesis process (phase 6). In 38% of papers we could not ascertain if reviewers had achieved any new interpretation of primary studies. In over 30% of papers seminal methodological texts which could have informed methods were not cited. We believe this is the first in-depth methodological systematic review of meta-ethnography conduct and reporting. Meta-ethnography is an evolving approach. Current reporting of methods, analysis and

Polysomnographic Characteristics of Sleep in Stroke: A Systematic Review and Meta-Analysis

PubMed Central

Baglioni, Chiara; Nissen, Christoph; Schweinoch, Adrian; Riemann, Dieter; Spiegelhalder, Kai; Berger, Mathias; Weiller, Cornelius; Sterr, Annette

2016-01-01

Background Research on sleep after stroke has focused mainly on sleep disordered breathing. However, the extend to which sleep physiology is altered in stroke survivors, how these alterations compare to healthy volunteers, and how sleep changes might affect recovery as well as physical and mental health has yet to be fully researched. Motivated by the view that a deeper understanding of sleep in stroke is needed to account for its role in health and well-being as well as its relevance for recovery and rehabilitation, we conducted a systematic review and meta-analysis of polysomnographic studies comparing stroke to control populations. Method Medline and PsycInfo databases were searched using "stroke" and words capturing polysomnographic parameters as search terms. This yielded 1692 abstracts for screening, with 15 meeting the criteria for systematic review and 9 for meta-analysis. Prisma best practice guidelines were followed for the systematic review; the Comprehensive Meta-Analysis software was used for random effects modelling. Results The meta-analysis revealed that patients with stroke have poorer sleep than controls. Patients had lower sleep efficiency (mean 75% vs 84%), shorter total-sleep-time (309.4 vs 340.3 min) and more wake-after-sleep-onset (97.2 vs 53.8 min). Patients also spend more time in stage 1 (13% vs 10%) and less time in stage 2 sleep (36% vs 45%) and slow-wave-sleep (10% vs 12%). No group differences were identified for REM sleep. The systematic review revealed a strong bias towards studies in the early recovery phase of stroke, with no study reporting specifically on patients in the chronic state. Moreover, participants in the control groups included community samples as well as other patients groups. Conclusions These results indicate poorer sleep in patients with stroke than controls. While strongly suggestive in nature, the evidence base is limited and methodologically diverse, and hands a clear mandate for further research. A particular

Grey Matter Alterations Co-Localize with Functional Abnormalities in Developmental Dyslexia: An ALE Meta-Analysis

PubMed Central

Linkersdörfer, Janosch; Lonnemann, Jan; Lindberg, Sven; Hasselhorn, Marcus; Fiebach, Christian J.

2012-01-01

The neural correlates of developmental dyslexia have been investigated intensively over the last two decades and reliable evidence for a dysfunction of left-hemispheric reading systems in dyslexic readers has been found in functional neuroimaging studies. In addition, structural imaging studies using voxel-based morphometry (VBM) demonstrated grey matter reductions in dyslexics in several brain regions. To objectively assess the consistency of these findings, we performed activation likelihood estimation (ALE) meta-analysis on nine published VBM studies reporting 62 foci of grey matter reduction in dyslexic readers. We found six significant clusters of convergence in bilateral temporo-parietal and left occipito-temporal cortical regions and in the cerebellum bilaterally. To identify possible overlaps between structural and functional deviations in dyslexic readers, we conducted additional ALE meta-analyses of imaging studies reporting functional underactivations (125 foci from 24 studies) or overactivations (95 foci from 11 studies ) in dyslexics. Subsequent conjunction analyses revealed overlaps between the results of the VBM meta-analysis and the meta-analysis of functional underactivations in the fusiform and supramarginal gyri of the left hemisphere. An overlap between VBM results and the meta-analysis of functional overactivations was found in the left cerebellum. The results of our study provide evidence for consistent grey matter variations bilaterally in the dyslexic brain and substantial overlap of these structural variations with functional abnormalities in left hemispheric regions. PMID:22916214

Lost at Sea: Summary Results of a Meta-Analysis of the Efficacy of Teacher Induction and Implications for Administrative Practice

ERIC Educational Resources Information Center

Shockley, Robert; Watlington, Eliah; Felsher, Rivka

2011-01-01

This paper summarizes a qualitative meta-analysis of the empirical research on the effectiveness of teacher induction programs over the last decade for the purpose of identifying the essential elements that make them effective in reducing teacher attrition. The study used Herzberg's two-factor theory of motivation as the theoretical framework for…

Candidate Loci for Yield-Related Traits in Maize Revealed by a Combination of MetaQTL Analysis and Regional Association Mapping

PubMed Central

Chen, Lin; An, Yixin; Li, Yong-xiang; Li, Chunhui; Shi, Yunsu; Song, Yanchun; Zhang, Dengfeng; Wang, Tianyu; Li, Yu

2017-01-01

Maize grain yield and related traits are complex and are controlled by a large number of genes of small effect or quantitative trait loci (QTL). Over the years, a large number of yield-related QTLs have been identified in maize and deposited in public databases. However, integrating and re-analyzing these data and mining candidate loci for yield-related traits has become a major issue in maize. In this study, we collected information on QTLs conferring maize yield-related traits from 33 published studies. Then, 999 of these QTLs were iteratively projected and subjected to meta-analysis to obtain metaQTLs (MQTLs). A total of 76 MQTLs were found across the maize genome. Based on a comparative genomics strategy, several maize orthologs of rice yield-related genes were identified in these MQTL regions. Furthermore, three potential candidate genes (Gene ID: GRMZM2G359974, GRMZM2G301884, and GRMZM2G083894) associated with kernel size and weight within three MQTL regions were identified using regional association mapping, based on the results of the meta-analysis. This strategy, combining MQTL analysis and regional association mapping, is helpful for functional marker development and rapid identification of candidate genes or loci. PMID:29312420

Neutrophil-to-lymphocyte ratio as a prognostic indicator in head and neck cancer: A systematic review and meta-analysis.

PubMed

Tham, Tristan; Bardash, Yonatan; Herman, Saori Wendy; Costantino, Peter David

2018-05-14

The purposes of this systematic review and meta-analysis were to investigate the relationship between the neutrophil-to-lymphocyte ratio (NLR) and prognosis in head and neck cancer. A systematic review and meta-analysis were done to investigate the role of NLR in overall survival (OS), disease-specific survival (DSS), disease-free survival (DFS), and progression-free survival (PFS). For qualitative analysis, 33 cohorts with over 10 072 patients were included. For quantitative analysis, 15 studies were included with 5562 patients. The pooled data demonstrated that an elevated NLR significantly predicted poorer OS and DSS. An elevated pretreatment NLR is a prognostic marker for head and neck cancer. It represents a simple and easily obtained marker that could be used to stratify groups of high-risk patients who might benefit from adjuvant therapy. © 2018 Wiley Periodicals, Inc.

Alcohol mixed with energy drink (AMED): A critical review and meta-analysis.

PubMed

Verster, Joris C; Benson, Sarah; Johnson, Sean J; Alford, Chris; Godefroy, Samuel Benrejeb; Scholey, Andrew

2018-03-01

The purpose of this systematic review and meta-analysis was to critically review the (1) prevalence of alcohol mixed with energy drink (AMED) consumption, (2) motives for AMED consumption, (3) correlates of AMED consumption, and (4) whether AMED consumption has an impact on (a) alcohol consumption, (b) subjective intoxication, and (c) risk-taking behavior. Overall a minority of the population consumes AMED, typically infrequently. Motives for AMED consumption are predominantly hedonistic and social. Meta-analyses revealed that AMED consumers drink significantly more alcohol than alcohol-only (AO) consumers. Within-subject comparisons restricted to AMED consumers revealed that alcohol consumption does not significantly differ between typical AMED and AO occasions. On past month heaviest drinking occasions, AMED users consume significantly less alcohol on AMED occasions when compared to AO occasions. AMED consumers experience significantly fewer negative consequences and risk-taking behavior on AMED occasions compared with AO occasions. Meta-analyses of subjective intoxication studies suggest that AMED consumption does not differentially affect subjective intoxication when compared to AO consumption. In conclusion, when compared to AO consumption, mixing alcohol with energy drink does not affect subjective intoxication and seems unlikely to increase total alcohol consumption, associated risk-taking behavior, nor other negative alcohol-related consequences. Further research may be necessary to fully reveal the effects of AMED. © 2018 The Authors Human Psychopharmacology: Clinical and Experimental Published by John Wiley & Sons Ltd.

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

PubMed

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.

Multivariate meta-analysis with an increasing number of parameters.

PubMed

Boca, Simina M; Pfeiffer, Ruth M; Sampson, Joshua N

2017-05-01

Meta-analysis can average estimates of multiple parameters, such as a treatment's effect on multiple outcomes, across studies. Univariate meta-analysis (UVMA) considers each parameter individually, while multivariate meta-analysis (MVMA) considers the parameters jointly and accounts for the correlation between their estimates. The performance of MVMA and UVMA has been extensively compared in scenarios with two parameters. Our objective is to compare the performance of MVMA and UVMA as the number of parameters, p, increases. Specifically, we show that (i) for fixed-effect (FE) meta-analysis, the benefit from using MVMA can substantially increase as p increases; (ii) for random effects (RE) meta-analysis, the benefit from MVMA can increase as p increases, but the potential improvement is modest in the presence of high between-study variability and the actual improvement is further reduced by the need to estimate an increasingly large between study covariance matrix; and (iii) when there is little to no between-study variability, the loss of efficiency due to choosing RE MVMA over FE MVMA increases as p increases. We demonstrate these three features through theory, simulation, and a meta-analysis of risk factors for non-Hodgkin lymphoma. © Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

The Contradictions of Telehealth User Experience in Chronic Obstructive Pulmonary Disease (COPD): A Qualitative Meta-Synthesis.

PubMed

Brunton, Lisa; Bower, Peter; Sanders, Caroline

2015-01-01

As the global burden of chronic disease rises, policy makers are showing a strong interest in adopting telehealth technologies for use in long term condition management, including COPD. However, there remain barriers to its implementation and sustained use. To date, there has been limited qualitative investigation into how users (both patients/carers and staff) perceive and experience the technology. We aimed to systematically review and synthesise the findings from qualitative studies that investigated user perspectives and experiences of telehealth in COPD management, in order to identify factors which may impact on uptake. Systematic review and meta-synthesis of published qualitative studies of user (patients, their carers and clinicians) experience of telehealth technologies for the management of Chronic Obstructive Pulmonary Disease. ASSIA, CINAHL, Embase, Medline, PsychInfo and Web of Knowledge databases were searched up to October 2014. Reference lists of included studies and reference lists of key papers were also searched. Quality appraisal was guided by an adapted version of the CASP qualitative appraisal tool. 705 references (after duplicates removed) were identified and 10 papers, relating to 7 studies were included in the review. Most authors of included studies had identified both positive and negative experiences of telehealth use in the management of COPD. Through a line of argument synthesis we were able to derive new insights from the data to identify three overarching themes that have the ability to either impede or promote positive user experience of telehealth in COPD: the influence on moral dilemmas of help seeking-(enables dependency or self-care); transforming interactions (increases risk or reassurance) and reconfiguration of 'work' practices (causes burden or empowerment). Findings from this meta-synthesis have implications for the future design and implementation of telehealth services. Future research needs to include potential users at

Speaking to Read: Meta-Analysis of Peer-Mediated Learning for English Language Learners

ERIC Educational Resources Information Center

Cole, Mikel W.

2014-01-01

This meta-analysis examines the effectiveness of a group of instructional approaches (i.e., cooperative, collaborative, and peer tutoring) at improving literacy outcomes for English language learners. Main effects analyses of a sample of 28 experimental and quasi-experimental studies reveal that peer-mediation is more effective for ELLs than…

Comparative Effectiveness of Treatments for Binge-Eating Disorder: Systematic Review and Network Meta-Analysis.

PubMed

Peat, Christine M; Berkman, Nancy D; Lohr, Kathleen N; Brownley, Kimberly A; Bann, Carla M; Cullen, Katherine; Quattlebaum, Mary J; Bulik, Cynthia M

2017-09-01

Psychological and pharmacological interventions for binge-eating disorder have previously demonstrated efficacy (compared with placebo or waitlist control); thus, we aimed to expand that literature with a review of comparative effectiveness. We searched MEDLINE,® EMBASE,® Cochrane Library, Academic OneFile, CINAHL® for binge-eating disorder treatment articles and selected studies using predetermined inclusion and exclusion criteria. Data were sufficient for network meta-analysis comparing two pharmacological interventions; psychological interventions were analysed qualitatively. In all, 28 treatment comparisons were included in this review: one pharmacological comparison (second-generation antidepressants versus lisdexamfetamine) and 26 psychological comparisons. Only three statistically significant differences emerged: lisdexamfetamine was better at increasing binge abstinence than second-generation antidepressants; therapist-led cognitive behavioural therapy was better at reducing binge-eating frequency than behavioural weight loss, but behavioural weight loss was better at reducing weight. The majority of other treatment comparisons revealed few significant differences between groups. Thus, patients and clinicians can choose from several effective treatment options. Copyright © 2017 John Wiley & Sons, Ltd and Eating Disorders Association. Copyright © 2017 John Wiley & Sons, Ltd and Eating Disorders Association.

Graphical tools for network meta-analysis in STATA.

PubMed

Chaimani, Anna; Higgins, Julian P T; Mavridis, Dimitris; Spyridonos, Panagiota; Salanti, Georgia

2013-01-01

Network meta-analysis synthesizes direct and indirect evidence in a network of trials that compare multiple interventions and has the potential to rank the competing treatments according to the studied outcome. Despite its usefulness network meta-analysis is often criticized for its complexity and for being accessible only to researchers with strong statistical and computational skills. The evaluation of the underlying model assumptions, the statistical technicalities and presentation of the results in a concise and understandable way are all challenging aspects in the network meta-analysis methodology. In this paper we aim to make the methodology accessible to non-statisticians by presenting and explaining a series of graphical tools via worked examples. To this end, we provide a set of STATA routines that can be easily employed to present the evidence base, evaluate the assumptions, fit the network meta-analysis model and interpret its results.

Graphical Tools for Network Meta-Analysis in STATA

PubMed Central

Chaimani, Anna; Higgins, Julian P. T.; Mavridis, Dimitris; Spyridonos, Panagiota; Salanti, Georgia

2013-01-01

Network meta-analysis synthesizes direct and indirect evidence in a network of trials that compare multiple interventions and has the potential to rank the competing treatments according to the studied outcome. Despite its usefulness network meta-analysis is often criticized for its complexity and for being accessible only to researchers with strong statistical and computational skills. The evaluation of the underlying model assumptions, the statistical technicalities and presentation of the results in a concise and understandable way are all challenging aspects in the network meta-analysis methodology. In this paper we aim to make the methodology accessible to non-statisticians by presenting and explaining a series of graphical tools via worked examples. To this end, we provide a set of STATA routines that can be easily employed to present the evidence base, evaluate the assumptions, fit the network meta-analysis model and interpret its results. PMID:24098547

Norovirus and Rotavirus Disease Severity in Children: Systematic Review and Meta-analysis.

PubMed

Riera-Montes, Margarita; O'Ryan, Miguel; Verstraeten, Thomas

2018-06-01

Rotaviruses (RVs) and noroviruses (NoVs) are the most common causes of severe acute gastroenteritis in children. It is generally accepted that RVs cause severe acute gastroenteritis in a higher proportion of cases compared with NoVs. To our knowledge, there are no systematic reviews and meta-analyses comparing the severity of NoV and RV disease. We searched MEDLINE for studies reporting data for NoV and RV medically attended disease severity in children. We included studies where all children had been tested for both NoV (reverse transcription polymerase chain reaction) and RV (enzyme-linked immunosorbent assay or reverse transcription polymerase chain reaction) and that reported disease severity using the Vesikari or modified Vesikari score, or provided clinical information on severity. We generated pooled estimates of the mean with 95% confidence intervals using random effects meta-analysis. We identified 266 publications, of which 31 were retained for qualitative analysis and 26 for quantitative analysis. Fourteen studies provided data on severity score for the meta-analysis. The pooled mean severity scores (95% confidence interval) among outpatients were 10 (8-12) and 11 (8-14) for NoV and RV, respectively. Among inpatients, they were 11 (9-13) for NoV and 12 (10-14) for RV. The difference was statistically significant among inpatients, but relatively small (1 point in a 20-point scale). About 20% more children with RV required rehydration when compared with children with NoV. NoV causes moderate to severe disease similar to RV in young children. This information should be useful for future evaluations of an eventual introduction of NoV vaccines in national immunization programs.

Technology's Effect on Achievement in Higher Education: A Stage I Meta-Analysis of Classroom Applications

ERIC Educational Resources Information Center

Schmid, Richard F.; Bernard, Robert M.; Borokhovski, Eugene; Tamim, Rana; Abrami, Philip C.; Wade, C. Anne; Surkes, Michael A.; Lowerison, Gretchen

2009-01-01

This paper reports the findings of a Stage I meta-analysis exploring the achievement effects of computer-based technology use in higher education classrooms (non-distance education). An extensive literature search revealed more than 6,000 potentially relevant primary empirical studies. Analysis of a representative sample of 231 studies (k = 310)…

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

ERIC Educational Resources Information Center

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…

Race and Older Mothers’ Differentiation: A Sequential Quantitative and Qualitative Analysis

PubMed Central

Sechrist, Jori; Suitor, J. Jill; Riffin, Catherine; Taylor-Watson, Kadari; Pillemer, Karl

2011-01-01

The goal of this paper is to demonstrate a process by which qualitative and quantitative approaches are combined to reveal patterns in the data that are unlikely to be detected and confirmed by either method alone. Specifically, we take a sequential approach to combining qualitative and quantitative data to explore race differences in how mothers differentiate among their adult children. We began with a standard multivariate analysis examining race differences in mothers’ differentiation among their adult children regarding emotional closeness and confiding. Finding no race differences in this analysis, we conducted an in-depth comparison of the Black and White mothers’ narratives to determine whether there were underlying patterns that we had been unable to detect in our first analysis. Using this method, we found that Black mothers were substantially more likely than White mothers to emphasize interpersonal relationships within the family when describing differences among their children. In our final step, we developed a measure of familism based on the qualitative data and conducted a multivariate analysis to confirm the patterns revealed by the in-depth comparison of the mother’s narratives. We conclude that using such a sequential mixed methods approach to data analysis has the potential to shed new light on complex family relations. PMID:21967639

Prenatal selective serotonin reuptake inhibitor use and the risk of autism spectrum disorder in children: A systematic review and meta-analysis.

PubMed

Kaplan, Yusuf C; Keskin-Arslan, Elif; Acar, Selin; Sozmen, Kaan

2016-12-01

To determine whether an up-to-date systematic review and meta-analysis of observational studies would support the previously suggested associations regarding prenatal selective serotonin reuptake inhibitor (SSRI) use and the risk for autism spectrum disorders (ASD) in children. PubMed/MEDLINE, Cochrane Central Register of Controlled Trials and Reprotox databases were searched; observational studies with an exposed and unexposed group were included. The meta-analysis of case-control studies demonstrated a significantly increased risk of ASD in the children whose mothers were prenatally exposed to SSRIs during different exposure time windows (except third trimester). The qualitative review of the cohort studies suggested inconsistent findings. The significant association between preconception-only SSRI exposure and ASD in the children and negative/inconsistent findings among cohort studies weaken the significant associations detected in this meta-analysis. We suggest that confounding by indication still cannot be ruled out regarding prenatal SSRI exposure and ASD in children. Copyright © 2016 Elsevier Inc. All rights reserved.

MTHFR gene polymorphism and risk of myeloid leukemia: a meta-analysis.

PubMed

Dong, Song; Liu, Yueling; Chen, Jieping

2014-09-01

An increasing body of evidence has shown that the amino acid changes at position 1298 might eliminate methylenetetrahydrofolate reductase (MTHFR) enzyme activity, leading to insufficient folic acid and subsequent human chromosome breakage. Epidemiological studies have linked MTHFR single-nucleotide polymorphism (SNP) rs1801131 to myeloid leukemia risk, with considerable discrepancy in their results. We therefore were prompted to clarify this issue by use of a meta-analysis. The search terms were used to cover the possible reports in the MEDLINE, Web of Knowledge, and China National Knowledge Infrastructure (CNKI) databases. Odds ratios were estimated to assess the association of SNP rs1801131 with myeloid leukemia risk. Statistical heterogeneity was detected using the Q-statistic and I (2) metric. Subgroup analysis was performed by ethnicity, histological subtype, and Hardy-Weinberg equilibrium (HWE). This meta-analysis of eight publications with a total of 1,114 cases and 3,227 controls revealed no global association. Nor did the subgroup analysis according to histological subtype and HWE show any significant associations. However, Asian individuals who harbored the CC genotype were found to have 1.66-fold higher risk of myeloid leukemia (odds ratio, 1.66; 95 % confidence interval, 1.10 to 2.49; P h = 0.342; I (2) = 0.114). Our meta-analysis has presented evidence supporting a possible association between the CC genotype of MTHFR SNP rs1801131 and myeloid leukemia in Asian populations.

Meta-analysis reveals gender difference in the association of liver cancer incidence and excess BMI.

PubMed

Yao, Kun-Fang; Ma, Ming; Ding, Guo-Yong; Li, Zhan-Ming; Chen, Hui-Ling; Han, Bing; Chen, Qiang; Jiang, Xin-Quan; Wang, Li-Shun

2017-09-22

Excess body weight has a positive association with risk of liver cancer, but the gender difference in the relationship between body mass index and liver cancer risk remains uncertainty. In this work, we performed meta-analysis for excess body weight and risk of liver cancer incidence to identify the gender difference. We searched the English-languages database and the Chinese literature databases to May 12, 2017. Overall, a total of 17 studies were included. Relative risks (RRs) with 95% confidence intervals was used to evaluate the strength of these associations. The RRs of liver cancer incidence for obese men and women were 2.04 (1.70-2.44) and 1.56 (1.37-1.78). The former one was significantly higher than the later one (P for interaction = 0.02). Notably, the RR of liver cancer incidence in non-Asian obese men was even higher than their counter part (2.31(1.85-2.91) vs. 1.56 (1.31-1.86), P for interaction = 0.01). Similar gender difference was observed in the dose-response curve. As example, at the point of BMI = 32 kg/m 2 , the RRs for men and women were 1.61 (1.45-1.79) and 1.41 (1.02-1.94) respectively. Findings from this meta-analysis indicate that obesity is associated with a higher risk of liver cancer incidence in men, especially in non-Asian men, which might partially contribute to the male dominance of liver cancer incidence.

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

PubMed

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.

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

PubMed Central

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

2016-01-01

Motivation: 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. Results: 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. Availability and implementation: Code is available at https://github.com/aalto-ics-kepaco Contacts: anna.cichonska@helsinki.fi or matti.pirinen@helsinki.fi Supplementary information: Supplementary data are available at Bioinformatics online. PMID:27153689

The Economic Value of Mangroves: A Meta-Analysis

Treesearch

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...

Pregnant women's perceptions of gestational weight gain: A systematic review and meta-synthesis of qualitative research.

PubMed

Vanstone, Meredith; Kandasamy, Sujane; Giacomini, Mita; DeJean, Deirdre; McDonald, Sarah D

2017-10-01

Excess gestational weight gain has numerous negative health outcomes for women and children, including high blood pressure, diabetes, and cesarean section (maternal) and high birth weight, trauma at birth, and asphyxia (infants). Excess weight gain in pregnancy is associated with a higher risk of long-term obesity in both mothers and children. Despite a concerted public health effort, the proportion of pregnant women gaining weight in excess of national guidelines continues to increase. To understand this phenomenon and offer suggestions for improving interventions, we conducted a systematic review of qualitative research on pregnant women's perceptions and experiences of weight gain in pregnancy. We used the methodology of qualitative meta-synthesis to analyze 42 empirical qualitative research studies conducted in high-income countries and published between 2005 and 2015. With this synthesis, we provide an account of the underlying factors and circumstances (barriers, facilitators, and motivators) that pregnant women identify as important for appropriate weight gain. We also offer a description of the strategies identified by pregnant women as acceptable and appropriate ways to promote healthy weight gain. Through our integrative analysis, we identify women's common perception on the struggle to enact health behaviors and physical, social, and environmental factors outside of their control. Effective and sensitive interventions to encourage healthy weight gain in pregnancy must consider the social environment in which decisions about weight take place. © 2016 John Wiley & Sons Ltd.

Serum vitamin D levels in relation to schizophrenia: a systematic review and meta-analysis of observational studies.

PubMed

Valipour, Ghazaleh; Saneei, Parvane; Esmaillzadeh, Ahmad

2014-10-01

Although several observational studies have investigated the association between vitamin D status and schizophrenia, we are aware of no comprehensive meta-analysis in this regard. We aimed to conduct a systematic review and a meta-analysis of observational studies to summarize the available data on the association between serum vitamin D levels and schizophrenia. A systematic research on all published articles until October 2013 was conducted in PubMed, ISI (Web of science), SCOPUS, and Google Scholar. All observational studies that had measured serum vitamin D levels in schizophrenic patients were included in the systematic review. After considering exclusion criteria, we had 19 studies for the systematic review that were included in three separate meta-analyses: 1) a meta-analysis on mean levels of 25-hydroxyvitamin D [25(OH)D] (n = 13); 2) a meta-analysis on the prevalence of vitamin D deficiency (n = 8); 3) a meta-analysis on odds ratios (n = 8). Findings from a meta-analysis on means revealed that the overall mean difference in serum 25(OH)D levels between schizophrenic patients and control participants was -5.91 ng/mL [95% confidence interval (CI) -10.68, -1.14]. Subgroup analyses based on study design, the patient's hospitalization status, study quality, and study location did not explain between-study heterogeneity; however, type of biomarker assessed [25-hydroxyvitamin D3 vs 25-hydroxyvitamin D (D2 & D3)] could account for some degree of heterogeneity. RESULTS from the meta-analysis on the prevalence of vitamin D deficiency indicated that the overall prevalence of vitamin D deficiency in schizophrenic patients was 65.3% (95% CI 46.4%-84.2%). Findings from the meta-analysis on odds ratios indicated that vitamin D-deficient persons were 2.16 times (95% CI 1.32, 3.56) more likely to have schizophrenia than those with vitamin D sufficiency. No evidence of heterogeneity was detected. We found a strong association between vitamin D deficiency and schizophrenia

Educational intervention on physical restraint use in long-term care facilities - Systematic review and meta-analysis.

PubMed

Lan, Shao-Huan; Lu, Li-Chin; Lan, Shou-Jen; Chen, Jong-Chen; Wu, Wen-Jun; Chang, Shen-Peng; Lin, Long-Yau

2017-08-01

"Physical restraint" formerly used as a measure of protection for psychiatric patients is now widely used. However, existing studies showed that physical restraint not only has inadequate effect of protection but also has negative effects on residents. To analyzes the impact of educational program on the physical restraint use in long-term care facilities. A systematic review with meta-analysis and meta-regression. Eight databases, including Cochrane Library, ProQuest, PubMed, EMBASE, EBSCO, Web of Science, Ovid Medline and Physiotherapy Evidence Database (PEDro), were searched up to January 2017. Eligible studies were classified by intervention and accessed for quality using the Quality Assessment Tool for quantitative studies. Sixteen research articles were eligible in the final review; 10 randomize control trail studies were included in the analysis. The meta-analysis revealed that the use of physical restraint was significantly less often in the experimental (education) group (OR = 0.55, 95% CI: 0.39 to 0.78, p < 0.001) compared to the control group. Meta-regression revealed the period of post education would have decreased the effect of the restraint educational program (β: 0.08, p = 0.002); instead, the longer education period and more times of education would have a stronger effect of reducing the use of physical restraint (β: -0.07, p < 0.001; β: -0.04, p = 0.056). The educational program had an effect on the reduced use of physical restraint. The results of meta-regression suggest that long-term care facilities should provide a continuous education program of physical restraint for caregivers. Copyright © 2017. Published by Elsevier Taiwan.

Association between individual differences in non-symbolic number acuity and math performance: a meta-analysis.

PubMed

Chen, Qixuan; Li, Jingguang

2014-05-01

Many recent studies have examined the association between number acuity, which is the ability to rapidly and non-symbolically estimate the quantity of items appearing in a scene, and symbolic math performance. However, various contradictory results have been reported. To comprehensively evaluate the association between number acuity and symbolic math performance, we conduct a meta-analysis to synthesize the results observed in previous studies. First, a meta-analysis of cross-sectional studies (36 samples, N = 4705) revealed a significant positive correlation between these skills (r = 0.20, 95% CI = [0.14, 0.26]); the association remained after considering other potential moderators (e.g., whether general cognitive abilities were controlled). Moreover, a meta-analysis of longitudinal studies revealed 1) that number acuity may prospectively predict later math performance (r = 0.24, 95% CI = [0.11, 0.37]; 6 samples) and 2) that number acuity is retrospectively correlated to early math performance as well (r = 0.17, 95% CI = [0.07, 0.26]; 5 samples). In summary, these pieces of evidence demonstrate a moderate but statistically significant association between number acuity and math performance. Based on the estimated effect sizes, power analyses were conducted, which suggested that many previous studies were underpowered due to small sample sizes. This may account for the disparity between findings in the literature, at least in part. Finally, the theoretical and practical implications of our meta-analytic findings are presented, and future research questions are discussed. Copyright © 2014 Elsevier B.V. All rights reserved.

Methodology Series Module 6: Systematic Reviews and Meta-analysis

PubMed Central

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. PMID:27904176

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

PubMed

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.

A meta-analysis of peripheral blood nerve growth factor levels in patients with schizophrenia.

PubMed

Qin, X-Y; Wu, H-T; Cao, C; Loh, Y P; Cheng, Y

2017-09-01

Neurotrophins particularly brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) are crucial modulators in the neurodevelopment and maintenance of central and peripheral nervous systems. Neurotrophin hypothesis of schizophrenia (SCZ) postulated that the changes in the brains of SCZ patients are the result of disturbances of developing processes involving neurotrophic factors. This hypothesis was mainly supported by the abnormal regulation of BDNF in SCZ, especially the decreased peripheral blood BDNF levels in SCZ patients validated by several meta-analyses. However, the regulation of NGF in SCZ remains unclear because of the inconsistent findings from the clinical studies. Therefore, we undertook, to the best of our knowledge, the first systematic review with a meta-analysis to quantitatively summarize the peripheral blood NGF data in SCZ patients compared with healthy control (HC) subjects. A systematic search of Pubmed, PsycINFO and Web of Science identified 13 articles encompassing a sample of 1693 individuals for the meta-analysis. Random-effects meta-analysis showed that patients with SCZ had significantly decreased peripheral blood levels of NGF when compared with the HC subjects (Hedges's g=-0.633, 95% confidence interval (CI)=-0.948 to -0.318, P<0.001). Subgroup analyses revealed reduced NGF levels both in serum (Hedges's g=-0.671, 95% CI=-1.259 to -0.084, P=0.025) and plasma (Hedges's g=-0.621, 95% CI=-0.980 to -0.261, P<0.001) of the patients, and in drug-free (Hedges's g=-0.670, 95% CI=-1.118 to -0.222, P=0.003) and medicated (Hedges's g=-0.357, 95% CI=-0.592 to -0.123, P=0.003) patients with SCZ. Furthermore, meta-regression analyses showed that age, gender and sample size had no moderating effects on the outcome of the meta-analysis, whereas disease severity might be a confounding factor for the meta-analysis. These results demonstrated that patients with SCZ are accompanied by the decreased peripheral blood NGF levels, strengthening

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

PubMed

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.

Lucid dreaming incidence: A quality effects meta-analysis of 50years of research.

PubMed

Saunders, David T; Roe, Chris A; Smith, Graham; Clegg, Helen

2016-07-01

We report a quality effects meta-analysis on studies from the period 1966-2016 measuring either (a) lucid dreaming prevalence (one or more lucid dreams in a lifetime); (b) frequent lucid dreaming (one or more lucid dreams in a month) or both. A quality effects meta-analysis allows for the minimisation of the influence of study methodological quality on overall model estimates. Following sensitivity analysis, a heterogeneous lucid dreaming prevalence data set of 34 studies yielded a mean estimate of 55%, 95% C. I. [49%, 62%] for which moderator analysis showed no systematic bias for suspected sources of variability. A heterogeneous lucid dreaming frequency data set of 25 studies yielded a mean estimate of 23%, 95% C. I. [20%, 25%], moderator analysis revealed no suspected sources of variability. These findings are consistent with earlier estimates of lucid dreaming prevalence and frequent lucid dreaming in the population but are based on more robust evidence. Copyright © 2016 Elsevier Inc. All rights reserved.

Pesticide exposure and risk of Alzheimer’s disease: a systematic review and meta-analysis

NASA Astrophysics Data System (ADS)

Yan, Dandan; Zhang, Yunjian; Liu, Liegang; Yan, Hong

2016-09-01

Evidence suggests that lifelong cumulative exposure to pesticides may generate lasting toxic effects on the central nervous system and contribute to the development of Alzheimer’s disease (AD). A number of reports indicate a potential association between long-term/low-dose pesticide exposure and AD, but the results are inconsistent. Therefore, we conducted a meta-analysis to clarify this association. Relevant studies were identified according to inclusion criteria. Summary odds ratios (ORs) were calculated using fixed-effects models. A total of seven studies were included in our meta-analysis. A positive association was observed between pesticide exposure and AD (OR = 1.34 95% confidence interval [CI] = 1.08, 1.67; n = 7). The summary ORs with 95% CIs from the crude and adjusted effect size studies were 1.14 (95% CI = 0.94, 1.38; n = 7) and 1.37 (95% CI = 1.09, 1.71; n = 5), respectively. The sensitivity analyses of the present meta-analysis did not substantially modify the association between pesticide exposure and AD. Subgroup analyses revealed that high-quality studies tended to show significant relationships. The present meta-analysis suggested a positive association between pesticide exposure and AD, confirming the hypothesis that pesticide exposure is a risk factor for AD. Further high-quality cohort and case-control studies are required to validate a causal relationship.

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

PubMed

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

Social projection to ingroups and outgroups: a review and meta-analysis.

PubMed

Robbins, Jordan M; Krueger, Joachim I

2005-01-01

Social projection is the tendency to expect similarities between oneself and others. A review of the literature and a meta-analysis reveal that projection is stronger when people make judgments about ingroups than when they make judgments about outgroups. Analysis of moderator variables further reveals that ingroup projection is stronger for laboratory groups than for real social categories. The mode of analysis (i.e., nomothetic vs. idiographic) and the order of judgments (i.e., self or group judged first) have no discernable effects. Outgroup projection is positive, but small in size. Together, these findings support the view that projection can serve as an egocentric heuristic for inductive reasoning. The greater strength of ingroup projection can contribute to ingroup-favoritism, perceptions of ingroup homogeneity, and cooperation with ingroup members.

Does albendazole affect seizure remission and computed tomography response in children with neurocysticercosis? A Systematic review and meta-analysis.

PubMed

Mazumdar, Maitreyi; Pandharipande, Pari; Poduri, Annapurna

2007-02-01

A recent trial suggested that albendazole reduces seizures in adults with neurocysticercosis. There is still no consensus regarding optimal management of neurocysticercosis in children. The authors conducted a systematic review and meta-analysis to assess the efficacy of albendazole in children with neurocysticercosis, by searching the Cochrane Databases, MEDLINE, EMBASE, and LILACS. Three reviewers extracted data using an intent-to-treat analysis. Random effects models were used to estimate relative risks. Four randomized trials were selected for meta-analysis, and 10 observational studies were selected for qualitative review. The relative risk of seizure remission in treatment versus control was 1.26 (1.09, 1.46). The relative risk of improvement in computed tomography in these trials was 1.15 (0.97, 1.36). Review of observational studies showed conflicting results, likely owing to preferential administration of albendazole to sicker children.

The experience of lived space in persons with dementia: a systematic meta-synthesis.

PubMed

Førsund, Linn Hege; Grov, Ellen Karine; Helvik, Anne-Sofie; Juvet, Lene Kristine; Skovdahl, Kirsti; Eriksen, Siren

2018-02-01

Identifying how persons with dementia experience lived space is important for enabling supportive living environments and creating communities that compensate for the fading capabilities of these persons. Several single studies have explored this topic; however, few studies have attempted to explicitly review and synthesize this research literature. The aim of this systematic meta-synthesis was therefore to interpret and synthesize knowledge regarding persons with dementia's experience of space. A systematic, computerized search of AgeLine, CINAHL Complete, Embase, Medline and PsycINFO was conducted using a search strategy that combined MeSH terms and text words for different types of dementia with different descriptions of experience. Studies with 1) a sample of persons with dementia, 2) qualitative interviews as a research method and 3) a description of experiences of lived space were included. The search resulted in 1386 articles, of which 136 were identified as eligible and were read and assessed using the CASP criteria. The analysis was inspired by qualitative content analyses. This interpretative qualitative meta-synthesis included 45 articles encompassing interviews with 672 persons with dementia. The analysis showed that living in one's own home and living in long-term care established different settings and posed diverse challenges for the experience of lived space in persons with dementia. The material revealed four main categories that described the experience of lived space: (1) belonging; (2) meaningfulness; (3) safety and security; and (4) autonomy. It showed how persons with dementia experienced a reduction in their lived space due to the progression of dementia. A comprehensive understanding of the categories led to the latent theme: "Living with dementia is like living in a space where the walls keep closing in". This meta-synthesis reveals a process whereby lived space gradually becomes smaller for persons with dementia. This underscores the

Meta-Analysis of Drainage Versus No Drainage After Laparoscopic Cholecystectomy

PubMed Central

Lucarelli, Pierino; Di Filippo, Annalisa; De Angelis, Francesco; Stipa, Francesco; Spaziani, Erasmo

2014-01-01

Background and Objectives: Routine drainage after laparoscopic cholecystectomy is still controversial. This meta-analysis was performed to assess the role of drains in reducing complications in laparoscopic cholecystectomy. Methods: An electronic search of Medline, Science Citation Index Expanded, Scopus, and the Cochrane Library database from January 1990 to June 2013 was performed to identify randomized clinical trials that compare prophylactic drainage with no drainage in laparoscopic cholecystectomy. The odds ratio for qualitative variables and standardized mean difference for continuous variables were calculated. Results: Twelve randomized controlled trials were included in the meta-analysis, involving 1939 patients randomized to a drain (960) versus no drain (979). The morbidity rate was lower in the no drain group (odds ratio, 1.97; 95% confidence interval, 1.26 to 3.10; P = .003). The wound infection rate was lower in the no drain group (odds ratio, 2.35; 95% confidence interval, 1.22 to 4.51; P = .01). Abdominal pain 24 hours after surgery was less severe in the no drain group (standardized mean difference, 2.30; 95% confidence interval, 1.27 to 3.34; P < .0001). No significant difference was present with respect to the presence and quantity of subhepatic fluid collection, shoulder tip pain, parenteral ketorolac consumption, nausea, vomiting, and hospital stay. Conclusion: This study was unable to prove that drains were useful in reducing complications in laparoscopic cholecystectomy. PMID:25516708

Pharmacological Control of Complications Following to Third Molar Removal: Evidence Based on A Meta-Analysis.

PubMed

Isiordia-Espinoza, Mario Alberto; Bologna-Molina, Ronell Eduardo; Hernández-Miramontes, Ycenna Ailed; Zapata-Morales, Juan Ramón; Alonso-Castro, Angel Jobsabad; Martínez-Morales, Flavio; Sánchez-Enriquez, Sergio; Serafín-Higuera, Nicolás Addiel; Pérez-Cortez, Guillermo; Franco-de la Torre, Lorenzo

2018-06-26

The purpose of this meta-analysis was to evaluate the clinical efficacy of non-steroidal anti-inflammatory drugs and dexamethasone on the trismus, postsurgical pain, facial swelling, as well as the analgesic consumption after third molar surgery. The reports were identified in the most important medical databases. Those studies that met the requirements were fully assessed according to the inclusion and exclusion criteria. The quality of each report was evaluated with the Oxford Quality Scale and using the Cochrane Collaboration's risk of bias tool. Each meta-analysis was done using the technique of mean difference and 95% confidence intervals employing a random effects model with the Review Manager 5.3., from the Cochrane Library. Significant statistical difference was accepted when the p value was less than 0.05 on the test of overall effect (Z value). Qualitative evaluation was done using the data of 330 patients extracted from seven articles and the quantitative assessment with data of 200 patients from three reports. It was not observed difference among non-steroidal anti-inflammatory drugs and dexamethasone in any of the clinical effectiveness indicators. The outcomes of our meta-analysis indicate that non-steroidal anti-inflammatory drugs and dexamethasone have good therapeutic effect for the management of inflammatory complications following to third molar surgery. © Georg Thieme Verlag KG Stuttgart · New York.

Meta-Analysis and the Solomon Four-Group Design.

ERIC Educational Resources Information Center

Sawilowsky, Shlomo; And Others

1994-01-01

A Monte Carlo study considers the use of meta analysis with the Solomon four-group design. Experiment-wise Type I error properties and the relative power properties of Stouffer's Z in the Solomon four-group design are explored. Obstacles to conducting meta analysis in the Solomon design are discussed. (SLD)

Non-cognate translation priming in masked priming lexical decision experiments: A meta-analysis.

PubMed

Wen, Yun; van Heuven, Walter J B

2017-06-01

The masked translation priming paradigm has been widely used in the last 25 years to investigate word processing in bilinguals. Motivated by studies reporting mixed findings, in particular for second language (L2) to first language (L1) translation priming, we conducted, for the first time in the literature, a meta-analysis of 64 masked priming lexical decision experiments across 24 studies to assess the effect sizes of L1-L2 and L2-L1 non-cognate translation priming effects in bilinguals. Our meta-analysis also investigated the influence of potential moderators of translation priming effects. The results provided clear evidence of significant translation priming effects for both directions, with L1-L2 translation priming significantly larger than L2-L1 translation priming (i.e., effect size of 0.86 vs. 0.31). The analyses also revealed that L1-L2 translation effect sizes were moderated by the interval between prime and target (ISI), whereas L2-L1 translation effect sizes were modulated by the number of items per cell. Theoretical and methodological implications of this meta-analysis are discussed and recommendations for future studies are provided.

Curcuminoids Lower Plasma Leptin Concentrations: A Meta-analysis.

PubMed

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.

Relationship between hypothyroidism and the incidence of gestational diabetes: A meta-analysis.

PubMed

Gong, Li-Li; Liu, He; Liu, Li-Hong

2016-04-01

Hypothyroidism disorders and gestational diabetes are among the most common endocrinopathies during pregnancy. We conducted a meta-analysis to investigate whether hypothyroidism in pregnancy is associated with gestational diabetes risk. Published literature from PubMed and EMBASE were searched for eligible publications. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using a fixed- or random-effects model. Seven articles described the relationship between hypothyroidism and risk of gestational diabetes. This meta-analysis revealed that overt hypothyroidism was associated with an increased risk of gestational diabetes (OR 1.892, 95% CI 1.679-2.132, p < 0.001). The relative risk of gestational diabetes was also increased in subclinical hypothyroidism, with the OR of 1.558 (95% CI 1.292-1.877, p < 0.001). There was no evidence of significant association between hypothyroxinemia and risk of gestational diabetes (OR 1.394, 95% CI 0.753-2.580, p = 0.291). The OR for all of the hypothyroidism was 1.749 (95% CI 1.586-1.928, p < 0.001), and an association was found. Results of this meta-analysis indicate that hypothyroidism may be a risk factor for gestational diabetes. Copyright © 2016. Published by Elsevier B.V.

A meta-ethnography of the acculturation and socialization experiences of migrant care workers.

PubMed

Ho, Ken H M; Chiang, Vico C L

2015-02-01

To report a meta-ethnography of qualitative research studies exploring the acculturation and socialization experiences of migrant care workers. Migrant care workers are increasingly participating in health and social care in developed countries. There is a need to understand this increasingly socioculturally diversified workforce. A comprehensive search through 12 databases and a manual search of journals related to transculture for studies on socialization and acculturation experiences (published 1993-2013) was completed. The inclusion criteria were peer-reviewed studies on the acculturation or socialization experiences of migrant care workers published in English in any country, using a qualitative or mixed-methods approach. This meta-ethnography employed the seven-phase Noblit and Hare method with reciprocal translation, refutational synthesis and lines-of-argument to synthesize qualitative studies. Three main themes were identified: (a) schema for the migration dream: optimism; (b) the reality of the migration dream: so close, yet so far; and (c) resilience: from chaos to order. A general framework of motivated psychosocial and behavioural adaptation was proposed. This meta-ethnography also revealed the vulnerabilities of migrant nurses in the process of acculturation and socialization. The general framework of behavioural and psychosocial adaptation revealed factors that impede and facilitate behavioural and psychosocial changes. Strategies to enrich external and internal resources should be targeted at encouraging multiculturalism and at improving the psychosocial resources of migrant care workers. It is suggested that research investigating the prominence of nursing vulnerabilities be conducted. © 2014 John Wiley & Sons Ltd.

Tooth erosion and eating disorders: a systematic review and meta-analysis.

PubMed

Hermont, Ana Paula; Oliveira, Patrícia A D; Martins, Carolina C; Paiva, Saul M; Pordeus, Isabela A; Auad, Sheyla M

2014-01-01

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. 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? 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. 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). 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.

Comparing Active Pediatric Obesity Treatments Using Meta-Analysis

ERIC Educational Resources Information Center

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:…

Dealing with the Conflicting Results of Psycholinguistic Experiments: How to Resolve Them with the Help of Statistical Meta-analysis.

PubMed

Rákosi, Csilla

2018-01-22

This paper proposes the use of the tools of statistical meta-analysis as a method of conflict resolution with respect to experiments in cognitive linguistics. With the help of statistical meta-analysis, the effect size of similar experiments can be compared, a well-founded and robust synthesis of the experimental data can be achieved, and possible causes of any divergence(s) in the outcomes can be revealed. This application of statistical meta-analysis offers a novel method of how diverging evidence can be dealt with. The workability of this idea is exemplified by a case study dealing with a series of experiments conducted as non-exact replications of Thibodeau and Boroditsky (PLoS ONE 6(2):e16782, 2011. https://doi.org/10.1371/journal.pone.0016782 ).

Meta-analysis of magnitudes, differences and variation in evolutionary parameters.

PubMed

Morrissey, M B

2016-10-01

Meta-analysis is increasingly used to synthesize major patterns in the large literatures within ecology and evolution. Meta-analytic methods that do not account for the process of observing data, which we may refer to as 'informal meta-analyses', may have undesirable properties. In some cases, informal meta-analyses may produce results that are unbiased, but do not necessarily make the best possible use of available data. In other cases, unbiased statistical noise in individual reports in the literature can potentially be converted into severe systematic biases in informal meta-analyses. I first present a general description of how failure to account for noise in individual inferences should be expected to lead to biases in some kinds of meta-analysis. In particular, informal meta-analyses of quantities that reflect the dispersion of parameters in nature, for example, the mean absolute value of a quantity, are likely to be generally highly misleading. I then re-analyse three previously published informal meta-analyses, where key inferences were of aspects of the dispersion of values in nature, for example, the mean absolute value of selection gradients. Major biological conclusions in each original informal meta-analysis closely match those that could arise as artefacts due to statistical noise. I present alternative mixed-model-based analyses that are specifically tailored to each situation, but where all analyses may be implemented with widely available open-source software. In each example meta-re-analysis, major conclusions change substantially. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

Diagnostic value of 18F-FDG-PET/CT for the evaluation of solitary pulmonary nodules: a systematic review and meta-analysis.

PubMed

Ruilong, Zong; Daohai, Xie; Li, Geng; Xiaohong, Wang; Chunjie, Wang; Lei, Tian

2017-01-01

To carry out a meta-analysis on the performance of fluorine-18-fluorodeoxyglucose (F-FDG) PET/computed tomography (PET/CT) for the evaluation of solitary pulmonary nodules. In the meta-analysis, we performed searches of several electronic databases for relevant studies, including Google Scholar, PubMed, Cochrane Library, and several Chinese databases. The quality of all included studies was assessed by Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2). Two observers independently extracted data of eligible articles. For the meta-analysis, the total sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratios were pooled. A summary receiver operating characteristic curve was constructed. The I-test was performed to assess the impact of study heterogeneity on the results of the meta-analysis. Meta-regression and subgroup analysis were carried out to investigate the potential covariates that might have considerable impacts on heterogeneity. Overall, 12 studies were included in this meta-analysis, including a total of 1297 patients and 1301 pulmonary nodules. The pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio with corresponding 95% confidence intervals (CIs) were 0.82 (95% CI, 0.76-0.87), 0.81 (95% CI, 0.66-0.90), 4.3 (95% CI, 2.3-7.9), and 0.22 (95% CI, 0.16-0.30), respectively. Significant heterogeneity was observed in sensitivity (I=81.1%) and specificity (I=89.6%). Subgroup analysis showed that the best results for sensitivity (0.90; 95% CI, 0.68-0.86) and accuracy (0.93; 95% CI, 0.90-0.95) were present in a prospective study. The results of our analysis suggest that PET/CT is a useful tool for detecting malignant pulmonary nodules qualitatively. Although current evidence showed moderate accuracy for PET/CT in differentiating malignant from benign solitary pulmonary nodules, further work needs to be carried out to improve its reliability.

Describing qualitative research undertaken with randomised controlled trials in grant proposals: a documentary analysis

PubMed Central

2014-01-01

Background There is growing recognition of the value of conducting qualitative research with trials in health research. It is timely to reflect on how this qualitative research is presented in grant proposals to identify lessons for researchers and research commissioners. As part of a larger study focusing on how to maximise the value of undertaking qualitative research with trials, we undertook a documentary analysis of proposals of funded studies. Methods Using the metaRegister of Controlled Trials (mRCT) database we identified trials funded in the United Kingdom, ongoing between 2001 and 2010, and reporting the use of qualitative research. We requested copies of proposals from lead researchers. We extracted data from the proposals using closed and open questions, analysed using descriptive statistics and content analysis respectively. Results 2% (89/3812) of trials in the mRCT database described the use of qualitative research undertaken with the trial. From these 89 trials, we received copies of 36 full proposals, of which 32 met our inclusion criteria. 25% used less than a single paragraph to describe the qualitative research. The aims of the qualitative research described in these proposals focused mainly on the intervention or trial conduct. Just over half (56%) of the proposals included an explicit rationale for conducting the qualitative research with the trial, the most frequent being to optimise implementation into clinical practice or to interpret trial findings. Key information about methods, expertise and resources was missing in a large minority of proposals, in particular sample size, type of analysis, and non-personnel resources. 28% specifically stated that qualitative researchers would conduct the qualitative research. Conclusions Our review of proposals of successfully funded studies identified good practice but also identified limited space given to describing the qualitative research, with an associated lack of attention to the rationale for

A-MADMAN: Annotation-based microarray data meta-analysis tool

PubMed Central

Bisognin, Andrea; Coppe, Alessandro; Ferrari, Francesco; Risso, Davide; Romualdi, Chiara; Bicciato, Silvio; Bortoluzzi, Stefania

2009-01-01

Background Publicly available datasets of microarray gene expression signals represent an unprecedented opportunity for extracting genomic relevant information and validating biological hypotheses. However, the exploitation of this exceptionally rich mine of information is still hampered by the lack of appropriate computational tools, able to overcome the critical issues raised by meta-analysis. Results This work presents A-MADMAN, an open source web application which allows the retrieval, annotation, organization and meta-analysis of gene expression datasets obtained from Gene Expression Omnibus. A-MADMAN addresses and resolves several open issues in the meta-analysis of gene expression data. Conclusion A-MADMAN allows i) the batch retrieval from Gene Expression Omnibus and the local organization of raw data files and of any related meta-information, ii) the re-annotation of samples to fix incomplete, or otherwise inadequate, metadata and to create user-defined batches of data, iii) the integrative analysis of data obtained from different Affymetrix platforms through custom chip definition files and meta-normalization. Software and documentation are available on-line at . PMID:19563634

TNF -308 G/A Polymorphism and Risk of Acne Vulgaris: A Meta-Analysis

PubMed Central

Yang, Jian-Kang; Wu, Wen-Juan; Qi, Jue; He, Li; Zhang, Ya-Ping

2014-01-01

Background The -308 G/A polymorphism in the tumor necrosis factor (TNF) gene has been implicated in the risk of acne vulgaris, but the results are inconclusive. The present meta-analysis aimed to investigate the overall association between the -308 G/A polymorphism and acne vulgaris risk. Methods We searched in Pubmed, Embase, Web of Science and CNKI for studies evaluating the association between the -308 G/A gene polymorphism and acne vulgaris risk. Data were extracted and statistical analysis was performed using STATA 12.0 software. Results A total of five publications involving 1553 subjects (728 acne vulgaris cases and 825 controls) were included in this meta-analysis. Combined analysis revealed a significant association between this polymorphism and acne vulgaris risk under recessive model (OR = 2.73, 95% CI: 1.37–5.44, p = 0.004 for AA vs. AG + GG). Subgroup analysis by ethnicity showed that the acne vulgaris risk associated with the -308 G/A gene polymorphism was significantly elevated among Caucasians under recessive model (OR = 2.34, 95% CI: 1.13–4.86, p = 0.023). Conclusion This meta-analysis suggests that the -308 G/A polymorphism in the TNF gene contributes to acne vulgaris risk, especially in Caucasian populations. Further studies among different ethnicity populations are needed to validate these findings. PMID:24498378

TNF-308 G/A polymorphism and risk of acne vulgaris: a meta-analysis.

PubMed

Yang, Jian-Kang; Wu, Wen-Juan; Qi, Jue; He, Li; Zhang, Ya-Ping

2014-01-01

The -308 G/A polymorphism in the tumor necrosis factor (TNF) gene has been implicated in the risk of acne vulgaris, but the results are inconclusive. The present meta-analysis aimed to investigate the overall association between the -308 G/A polymorphism and acne vulgaris risk. We searched in Pubmed, Embase, Web of Science and CNKI for studies evaluating the association between the -308 G/A gene polymorphism and acne vulgaris risk. Data were extracted and statistical analysis was performed using STATA 12.0 software. A total of five publications involving 1553 subjects (728 acne vulgaris cases and 825 controls) were included in this meta-analysis. Combined analysis revealed a significant association between this polymorphism and acne vulgaris risk under recessive model (OR = 2.73, 95% CI: 1.37-5.44, p = 0.004 for AA vs. AG + GG). Subgroup analysis by ethnicity showed that the acne vulgaris risk associated with the -308 G/A gene polymorphism was significantly elevated among Caucasians under recessive model (OR = 2.34, 95% CI: 1.13-4.86, p = 0.023). This meta-analysis suggests that the -308 G/A polymorphism in the TNF gene contributes to acne vulgaris risk, especially in Caucasian populations. Further studies among different ethnicity populations are needed to validate these findings.

A Qualitative Analysis of Suicide Ideation among Manitoban Farmers

ERIC Educational Resources Information Center

Sturgeon, Ryan; Morrissette, Patrick J.

2010-01-01

Canadian studies examining suicide among rural and farm populations remain scarce. To better understand this phenomenon, a qualitative research paradigm was used to analyze encounter forms of 29 individuals (24 men, 5 women) who called the Manitoban Farm and Rural Stress Line. Content analysis revealed 7 major themes: (a) coping mechanisms, (b)…

Effect of High-Frequency Transcranial Magnetic Stimulation on Craving in Substance Use Disorder: A Meta-Analysis.

PubMed

Maiti, Rituparna; Mishra, Biswa Ranjan; Hota, Debasish

2017-01-01

Repetitive transcranial magnetic stimulation (rTMS), a noninvasive, neuromodulatory tool, has been used to reduce craving in different substance use disorders. There are some studies that have reported conflicting and inconclusive results; therefore, this meta-analysis was conducted to evaluate the effect of high-frequency rTMS on craving in substance use disorder and to investigate the reasons behind the inconsistency across the studies. The authors searched clinical trials from MEDLINE, Cochrane databases, and International Clinical Trials Registry Platform. The PRISMA guidelines, as well as recommended meta-analysis practices, were followed in the selection process, analysis, and reporting of the findings. The effect estimate used was the standardized mean difference (Hedge's g), and heterogeneity across the considered studies was explored using subgroup analyses. The quality assessment was done using the Cochrane risk of bias tool, and sensitivity analysis was performed to check the influences on effect size by statistical models. After screening and assessment of eligibility, finally 10 studies were included for meta-analysis, which includes six studies on alcohol and four studies on nicotine use disorder. The random-model analysis revealed a pooled effect size of 0.75 (95% CI=0.29 to 1.21, p=0.001), whereas the fixed-model analysis showed a large effect size of 0.87 (95% CI=0.63 to 1.12, p<0.00001). Subgroup analysis for alcohol use disorder showed an effect size of -0.06 (95% CI=-0.89 to 0.77, p=0.88). In the case of nicotine use disorder, random-model analysis revealed an effect size of 1.00 (95% CI=0.48 to 1.55, p=0.0001), whereas fixed-model analysis also showed a large effect size of 0.96 (95% CI=0.71 to 1.22). The present meta-analysis identified a beneficial effect of high-frequency rTMS on craving associated with nicotine use disorder but not alcohol use disorder.

Association between BDNF levels and suicidal behaviour: a systematic review and meta-analysis.

PubMed

Eisen, Rebecca B; Perera, Stefan; Banfield, Laura; Anglin, Rebecca; Minuzzi, Luciano; Samaan, Zainab

2015-12-30

Suicidal behaviour is a complex phenomenon with a multitude of risk factors. Brain-derived neurotrophic factor (BDNF), a protein crucial to nervous system function, may be involved in suicide risk. The objective of this systematic review is to evaluate and summarize the literature examining the relationship between BDNF levels and suicidal behaviour. A predefined search strategy was used to search MEDLINE, EMBASE, PsychINFO, and CINAHL from inception to December 2015. Studies were included if they investigated the association between BDNF levels and suicidal behaviours (including completed suicide, attempted suicide, or suicidal ideation) by comparing BDNF levels in groups with and without suicidal behaviour. Only the following observational studies were included: case-control and cohort studies. Both clinical- and community-based samples were included. Screening, data extraction, and risk of bias assessment were conducted in duplicate. Six-hundred thirty-one articles were screened, and 14 were included in the review. Three studies that assessed serum BDNF levels in individuals with suicide attempts and controls were combined in a meta-analysis that showed no significant association between serum BDNF and suicide attempts. The remaining 11 studies were not eligible for the meta-analysis and provided inconsistent findings regarding associations between BDNF and suicidal behaviour. The findings of the meta-analysis indicate that there is no significant association between serum BDNF and attempted suicide. The qualitative review of the literature did not provide consistent support for an association between BDNF levels and suicidal behaviour. The evidence has significant methodological limitations. PROSPERO CRD42015015871.

Qualitative Secondary Analysis: A Case Exemplar.

PubMed

Tate, Judith Ann; Happ, Mary Beth

Qualitative secondary analysis (QSA) is the use of qualitative data that was collected by someone else or was collected to answer a different research question. Secondary analysis of qualitative data provides an opportunity to maximize data utility, particularly with difficult-to-reach patient populations. However, qualitative secondary analysis methods require careful consideration and explicit description to best understand, contextualize, and evaluate the research results. In this article, we describe methodologic considerations using a case exemplar to illustrate challenges specific to qualitative secondary analysis and strategies to overcome them. Copyright © 2017 National Association of Pediatric Nurse Practitioners. Published by Elsevier Inc. All rights reserved.

Systematic Review and Meta-Analysis of Patiromer and Sodium Zirconium Cyclosilicate: A New Armamentarium for the Treatment of Hyperkalemia.

PubMed

Meaney, Calvin J; Beccari, Mario V; Yang, Yang; Zhao, Jiwei

2017-04-01

To compare and contrast the efficacy and safety of patiromer and sodium zirconium cyclosilicate (ZS-9) in the treatment of hyperkalemia. A systematic review and meta-analysis of phase II and III clinical trial data was completed. Eight studies (two phase II and four phase III trials with two subgroup analyses) were included in the qualitative analysis, and six studies (two phase II and four phase III trials) were included in the meta-analysis. Significant heterogeneity was found in the meta-analysis with an I 2 value ranging from 80.6-99.6%. A random-effects meta-analysis was applied for all end points. Each clinical trial stratified results by hyperkalemia severity and dosing; therefore, these were considered separate treatment groups in the meta-analysis. For patiromer, a significant -0.70 mEq/L (95% confidence interval [CI] -0.48 to -0.91 mEq/L) change was noted in potassium at 4 weeks. At day 3 of patiromer treatment, potassium change was -0.36 mEq/L (range of standard deviation 0.07-0.30). The primary end point for ZS-9-change in potassium at 48 hours-was -0.67 mEq/L (95% CI -0.45 to -0.89 mEq/L). By 1 hour after ZS-9 administration, change in potassium was -0.17 mEq/L (95% CI -0.05 to -0.30). Analysis of pooled adverse effects from these trials indicates that patiromer was associated with more gastrointestinal upset (7.6% constipation, 4.5% diarrhea) and electrolyte depletion (7.1% hypomagnesemia), whereas ZS-9 was associated with the adverse effects of urinary tract infections (1.1%) and edema (0.9%). Patiromer and ZS-9 represent significant pharmacologic advancements in the treatment of hyperkalemia. Both agents exhibited statistically and clinically significant reductions in potassium for the primary end point of this meta-analysis. Given the adverse effect profile and the observed time-dependent effects, ZS-9 may play more of a role in treating acute hyperkalemia. © 2017 Pharmacotherapy Publications, Inc.

Bridging meta-analysis and the comparative method: a test of seed size effect on germination after frugivores' gut passage.

PubMed

Verdú, Miguel; Traveset, Anna

2004-02-01

Most studies using meta-analysis try to establish relationships between traits across taxa from interspecific databases and, thus, the phylogenetic relatedness among these taxa should be taken into account to avoid pseudoreplication derived from common ancestry. This paper illustrates, with a representative example of the relationship between seed size and the effect of frugivore's gut on seed germination, that meta-analytic procedures can also be phylogenetically corrected by means of the comparative method. The conclusions obtained in the meta-analytical and phylogenetical approaches are very different. The meta-analysis revealed that the positive effects that gut passage had on seed germination increased with seed size in the case of gut passage through birds whereas decreased in the case of gut passage through non-flying mammals. However, once the phylogenetic relatedness among plant species was taken into account, the effects of gut passage on seed germination did not depend on seed size and were similar between birds and non-flying mammals. Some methodological considerations are given to improve the bridge between the meta-analysis and the comparative method.

Are we hammering square pegs into round holes? An investigation of the meta-analyses of reading research with students who are d/Deaf or hard of hearing and students who are hearing.

PubMed

Wang, Ye; Williams, Cheri

2014-01-01

In a qualitative meta-analysis, the researchers systematically reviewed qualitative and quantitative meta-analyses on reading research with PK-12 students published after the 2000 National Reading Panel (NRP) report. Eleven qualitative and 39 quantitative meta-analyses were reviewed examining reading research with typically developing hearing students, special education hearing students (including English Language Learners), and d/Deaf or hard of hearing (d/Dhh) students. Generally, the meta-analysis yielded findings similar to and corroborative of the NRP's. Contradictory results (e.g., regarding the role of rhyme awareness in reading outcomes) most often resulted from differing definitions of interventions and their measurements. The analysis provided evidence of several instructional approaches that support reading development. On the basis of the qualitative similarity hypothesis (Paul, 2010, 2012; Paul & Lee, 2010; Paul & Wang, 2012; Paul, Wang, & Williams, 2013), the researchers argue that these instructional strategies also should effectively support d/Dhh children's reading development.

Meta-analysis using Dirichlet process.

PubMed

Muthukumarana, Saman; Tiwari, Ram C

2016-02-01

This article develops a Bayesian approach for meta-analysis using the Dirichlet process. The key aspect of the Dirichlet process in meta-analysis is the ability to assess evidence of statistical heterogeneity or variation in the underlying effects across study while relaxing the distributional assumptions. We assume that the study effects are generated from a Dirichlet process. Under a Dirichlet process model, the study effects parameters have support on a discrete space and enable borrowing of information across studies while facilitating clustering among studies. We illustrate the proposed method by applying it to a dataset on the Program for International Student Assessment on 30 countries. Results from the data analysis, simulation studies, and the log pseudo-marginal likelihood model selection procedure indicate that the Dirichlet process model performs better than conventional alternative methods. © The Author(s) 2012.

Evaluation of shoulder function in clavicular fracture patients after six surgical procedures based on a network meta-analysis.

PubMed

Huang, Shou-Guo; Chen, Bo; Lv, Dong; Zhang, Yong; Nie, Feng-Feng; Li, Wei; Lv, Yao; Zhao, Huan-Li; Liu, Hong-Mei

2017-01-01

Purpose Using a network meta-analysis approach, our study aims to develop a ranking of the six surgical procedures, that is, Plate, titanium elastic nail (TEN), tension band wire (TBW), hook plate (HP), reconstruction plate (RP) and Knowles pin, by comparing the post-surgery constant shoulder scores in patients with clavicular fracture (CF). Methods A comprehensive search of electronic scientific literature databases was performed to retrieve publications investigating surgical procedures in CF, with the stringent eligible criteria, and clinical experimental studies of high quality and relevance to our area of interest were selected for network meta-analysis. Statistical analyses were conducted using Stata 12.0. Results A total of 19 studies met our inclusion criteria were eventually enrolled into our network meta-analysis, representing 1164 patients who had undergone surgical procedures for CF (TEN group = 240; Plate group = 164; TBW group  =  180; RP group  =  168; HP group  =  245; Knowles pin group  =  167). The network meta-analysis results revealed that RP significantly improved constant shoulder score in patients with CF when compared with TEN, and the post-operative constant shoulder scores in patients with CF after Plate, TBW, HP, Knowles pin and TEN were similar with no statistically significant differences. The treatment relative ranking of predictive probabilities of constant shoulder scores in patients with CF after surgery revealed the surface under the cumulative ranking curves (SUCRA) value is the highest in RP. Conclusion The current network meta-analysis suggests that RP may be the optimum surgical treatment among six inventions for patients with CF, and it can improve the shoulder score of patients with CF. Implications for Rehabilitation RP improves shoulder joint function after surgical procedure. RP achieves stability with minimal complications after surgery. RP may be the optimum surgical treatment for

Clinical periodontal variables in patients with and without dementia-a systematic review and meta-analysis.

PubMed

Maldonado, Alejandra; Laugisch, Oliver; Bürgin, Walter; Sculean, Anton; Eick, Sigrun

2018-06-22

Considering the increasing number of elderly people, dementia has gained an important role in today's society. Although the contributing factors for dementia have not been fully understood, chronic periodontitis (CP) seems to have a possible link to dementia. To conduct a systematic review including meta-analysis in order to assess potential differences in clinical periodontal variables between patients with dementia and non-demented individuals. The following focused question was evaluated: is periodontitis associated with dementia? Electronic searches in two databases, MEDLINE and EMBASE, were conducted. Meta-analysis was performed with the collected data in order to find a statistically significant difference in clinical periodontal variables between the group of dementia and the cognitive normal controls. Forty-two articles remained for full text reading. Finally, seven articles met the inclusion criteria and only five studies provided data suitable for meta-analysis. Periodontal probing depth (PPD), bleeding on probing (BOP), gingival bleeding index (GBI), clinical attachment level (CAL), and plaque index (PI) were included as periodontal variables in the meta-analysis. Each variable revealed a statistically significant difference between the groups. In an attempt to reveal an overall difference between the periodontal variables in dementia patients and non-demented individuals, the chosen variables were transformed into units that resulted in a statistically significant overall difference (p < 0.00001). The current findings indicate that compared to systemically healthy individuals, demented patients show significantly worse clinical periodontal variables. However, further epidemiological studies including a high numbers of participants, the use of exact definitions both for dementia and chronic periodontitis and adjusted for cofounders is warranted. These findings appear to support the putative link between CP and dementia. Consequently, the need for

Meta-analysis: eating frequency and risk of colorectal cancer.

PubMed

Liu, Yanqiong; Tang, Weizhong; Zhai, Limin; Yang, Shi; Wu, Junrong; Xie, Li; Wang, Jian; Deng, Yan; Qin, Xue; Li, Shan

2014-04-01

Eating frequency has been implicated in the risk of colorectal cancer (CRC) in several epidemiological studies with contradictory and inconclusive findings. We performed a meta-analysis to evaluate their relationship. The pooled relative risk (RR) with 95% confidence interval (CI) was calculated to estimate the effects. A total of 15 eligible studies with 141,431 subjects and 11,248 cases were retrieved after a comprehensive search of the PubMed, Cochrane Library, and Web of Science databases up to October 2013. The overall meta-analysis revealed no strong significant association between eating frequency and risk of CRC in different eating occasion categories (1 meal/day): RR = 1.01, 95% CI 0.94-1.09, P = 0.709; 3 vs. <3 daily meals: RR = 1.17, 95% CI 0.93-1.46; 4 vs. <3 daily meals: RR = 1.13, 95% CI 0.92-1.38; ≥ 5 vs. <3 daily meals: RR = 0.95, 95% CI 0.61-1.47; 4 vs. ≤ 3 daily meals: RR = 1.18, 95% CI 0.92-1.51; and 1-2 vs. 3 or 4 daily meals: RR = 0.82, 95% CI 0.63-1.06). However, modest evidence of an increased risk of CRC in case-control studies (RR = 1.30; 95% CI, 1.11-1.52) and ≥ 5 vs. ≤ 3 meals group (RR = 1.30; 95% CI, 1.11-1.52) was observed. Our meta-analysis results do not support the hypothesis that eating frequency strongly reduced or increased the risk of CRC. Clinical randomized trials are required to evaluate this relationship further.

The polymorphisms K469E and G261R of intercellular adhesion molecule-1 and susceptibility to inflammatory bowel disease: a meta-analysis.

PubMed

Song, Gwan Gyu; Lee, Young Ho

2015-01-01

The aim of this study was to explore whether polymorphisms of intercellular adhesion molecule-1 (ICAM-1) are associated with susceptibility to Crohn's disease (CD) and ulcerative colitis (UC). The authors conducted a meta-analysis on the associations between the polymorphisms K469E and G241R of ICAM-1 and susceptibility to CD and UC. A total of 8 studies with 801 patients with CD, 672 patients with UC, and 1,828 controls were included in the meta-analysis. The meta-analysis revealed no association between CD and the ICAM-1 469E allele among the subjects (OR = 1.175, 95% CI = 0.901-1.533, p = 0.233). However, stratification by ethnicity indicated an association between the ICAM-1 469E allele and CD in Europeans (OR = 1.425, 95% CI = 1.013-2.002, p = 0.042). Meta-analysis using the homozygosity also showed an association with CD in Europeans (OR = 2.054, 95% CI = 1.036-4.073, p = 0.039). The meta-analysis revealed no association between UC and the ICAM-1 K469E polymorphism. No association between CD or UC and the ICAM-1 G241R polymorphism was observed. This meta-analysis demonstrates that the ICAM-1 K469E polymorphism may be associated with susceptibility to CD in Europeans, but no association was found between ICAM-1 K469E and UC. In contrast, the G241R polymorphism was not found to be associated with susceptibility to either CD or UC.

Conventional vs. e-learning in nursing education: A systematic review and meta-analysis.

PubMed

Voutilainen, Ari; Saaranen, Terhi; Sormunen, Marjorita

2017-03-01

By and large, in health professions training, the direction of the effect of e-learning, positive or negative, strongly depends on the learning outcome in question as well as on learning methods which e-learning is compared to. In nursing education, meta-analytically generated knowledge regarding the comparisons between conventional and e-learning is scarce. The aim of this review is to discover the size of the effect of e-learning on learning outcomes in nursing education and to assess the quality of studies in which e-learning has been compared to conventional learning. A systematic search of six electronic databases, PubMed, Ovid MEDLINE®, CINAHL (EBSCOhost), Cochrane Library, PsycINFO, and ERIC, was conducted in order to identify relevant peer-reviewed English language articles published between 2011 and 2015. The quality of the studies included as well as the risk of bias in each study was assessed. A random-effects meta-analysis was performed to generate a pooled mean difference in the learning outcome. Altogether, 10 studies were eligible for the quality assessment and meta-analysis. Nine studies were evaluated as good quality studies, but not without a risk of bias. Performance bias caused a high risk in nearly all the studies. In the meta-analysis, an e-learning method resulted in test scores that were, on average, five points higher than a conventional method on a 0-100 scale. Heterogeneity between the studies was very large. The size and direction of the effect of a learning method on learning outcomes appeared to be strongly situational. We suggest that meta-regressions should be performed instead of basic meta-analyses in order to reveal factors that cause variation in the learning outcomes of nursing education. It might be necessary to perform separate meta-analyses between e-learning interventions aimed at improving nursing knowledge and those aimed at improving nursing skills. Copyright © 2016 Elsevier Ltd. All rights reserved.

A meta-analysis of math performance in Turner syndrome.

PubMed

Baker, Joseph M; Reiss, Allan L

2016-02-01

Studies investigating the relationship between Turner syndrome and math learning disability have used a wide variation of tasks designed to test various aspects of mathematical competencies. Although these studies have revealed much about the math deficits common to Turner syndrome, their diversity makes comparisons between individual studies difficult. As a result, the consistency of outcomes among these diverse measures remains unknown. The overarching aim of this review is to provide a systematic meta-analysis of the differences in math and number performance between females with Turner syndrome and age-matched neurotypical peers. We provide a meta-analysis of behavioral performance in Turner syndrome relative to age-matched neurotypical populations on assessments of math and number aptitude. In total, 112 comparisons collected across 17 studies were included. Although 54% of all statistical comparisons in our analyses failed to reject the null hypothesis, our results indicate that meaningful group differences exist on all comparisons except those that do not require explicit calculation. Taken together, these results help elucidate our current understanding of math and number weaknesses in Turner syndrome, while highlighting specific topics that require further investigation. © 2015 Mac Keith Press.

Effectiveness and safety of vedolizumab for treatment of Crohn's disease: a systematic review and meta-analysis.

PubMed

Moćko, Paweł; Kawalec, Paweł; Smela-Lipińska, Beata; Pilc, Andrzej

2016-10-01

The aim of this systematic review (SR) and meta-analysis was to assess the efficacy and safety of vedolizumab in the treatment of Crohn's disease (CD). A systematic literature search was conducted in Medline/PubMed, Embase and Cochrane Library until 25 January, 2015. Included studies were critically appraised according to the PRISMA protocol. Assessment in specified subgroups of CD patients and meta-analysis with Revman software were performed. Two randomized controlled trial (RCTs) were included in a meta-analysis for the induction phase of therapy: GEMINI II and GEMINI III. The clinical response was significantly higher for patients who received vedolizumab compared to placebo in the general population (risk benefit (RB) = 1.48; p = 0.0006) and in both analyzed subgroups: patients with previous failure of anti-TNFs treatment (RB = 1.51; p = 0.006) and patients naive to earlier anti-TNFs (RB = 1.41; p = 0.001). The clinical remission in the general population and subpopulation of TNF-antagonist naive patients was significantly higher for patients who received vedolizumab compared to placebo (RB = 1.77; p = 0.003; RB = 2.29; p = 0.0004; respectively). Meta-analysis for adverse events, serious adverse events (SAEs) and serious infections, revealed that vedolizumab was as safe as placebo in the induction phase of therapy. The clinical response was significantly higher for patients who received vedolizumab in the general population and in both analyzed subgroups of patients. The clinical remission in the general population and subpopulation of TNF-antagonist naive patients was significantly higher for vedolizumab, but no significant differences were revealed in the subgroup of patients with previous TNF antagonist failure.

Con: Meta-analysis: some key limitations and potential solutions.

PubMed

Esterhuizen, Tonya M; Thabane, Lehana

2016-06-01

Meta-analysis, a statistical combination of results of several trials to produce a summary effect, has been subject to criticism in the past, mainly for the reasons of poor quality of included studies, heterogeneity between studies meta-analyzed and failing to address publication bias. These limitations can cause the results to be misleading, which is important if policy and practice decisions are based on systematic reviews and meta-analyses. We elaborate on these limitations and illustrate them with examples from the nephrology literature. Finally, we present some potential solutions, notably, education in meta-analysis for evidence producers and consumers as well as the use of individual patient data for meta-analyses. © The Author 2016. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

Measuring the statistical validity of summary meta-analysis and meta-regression results for use in clinical practice.

PubMed

Willis, Brian H; Riley, Richard D

2017-09-20

An important question for clinicians appraising a meta-analysis is: are the findings likely to be valid in their own practice-does the reported effect accurately represent the effect that would occur in their own clinical population? To this end we advance the concept of statistical validity-where the parameter being estimated equals the corresponding parameter for a new independent study. Using a simple ('leave-one-out') cross-validation technique, we demonstrate how we may test meta-analysis estimates for statistical validity using a new validation statistic, Vn, and derive its distribution. We compare this with the usual approach of investigating heterogeneity in meta-analyses and demonstrate the link between statistical validity and homogeneity. Using a simulation study, the properties of Vn and the Q statistic are compared for univariate random effects meta-analysis and a tailored meta-regression model, where information from the setting (included as model covariates) is used to calibrate the summary estimate to the setting of application. Their properties are found to be similar when there are 50 studies or more, but for fewer studies Vn has greater power but a higher type 1 error rate than Q. The power and type 1 error rate of Vn are also shown to depend on the within-study variance, between-study variance, study sample size, and the number of studies in the meta-analysis. Finally, we apply Vn to two published meta-analyses and conclude that it usefully augments standard methods when deciding upon the likely validity of summary meta-analysis estimates in clinical practice. © 2017 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd. © 2017 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd.

Developmental defects of enamel and dental caries in the primary dentition: A systematic review and meta-analysis.

PubMed

Costa, Francine S; Silveira, Ethieli R; Pinto, Gabriela S; Nascimento, Gustavo G; Thomson, William Murray; Demarco, Flávio F

2017-05-01

This systematic review and meta-analysis evaluated the association between developmental defects of enamel and dental caries in the primary dentition. Electronic searches were performed in PubMed, Web of Knowledge, Scopus and Scielo for the identification of relevant studies. Observational studies that examined the association between developmental defects of enamel and dental caries in the deciduous dentition were included. Additionally, meta-analysis, funnel plots and sensitivity analysis were employed to synthesize the available evidence. Multivariable meta-regression analysis was performed to explore heterogeneity among studies. A total of 318 articles were identified in the electronic searches. Of those, 16 studies were included in the meta-analysis. Pooled estimates revealed that children with developmental defects of enamel had higher odds of having dental caries (OR 3.32; 95%CI 2.41-4.57), with high heterogeneity between studies (I 2 80%). Methodological characteristic of the studies, such as where it was conducted, the examined teeth and the quality of the study explained about 30% of the variability. Concerning type of defect, children with hypoplasia and diffuse opacities had higher odds of having dental caries (OR 4.28; 95%CI 2.24-8.15; OR1.42; 95%CI 1.15-1.76, respectively). This systematic review and meta-analysis demonstrates a clear association between developmental defects of enamel and dental caries in the primary dentition. Copyright © 2017 Elsevier Ltd. All rights reserved.

Diagnosis and management of perinatal depression and anxiety in general practice: a meta-synthesis of qualitative studies.

PubMed

Ford, Elizabeth; Lee, Suzanne; Shakespeare, Judy; Ayers, Susan

2017-08-01

Up to 20% of women experience anxiety and depression during the perinatal period. In the UK, management of perinatal mental health falls under the remit of GPs. This review aimed at synthesising the available information from qualitative studies on GPs' attitudes, recognition, and management of perinatal anxiety and depression. Meta-synthesis of the available published qualitative evidence on GPs' recognition and management of perinatal anxiety and depression. A systematic search was conducted on Embase, Medline, PsycInfo, Pubmed, Scopus, and Web of Science, and grey literature was searched using Google, Google Scholar, and British Library EThOS. Papers and reports were eligible for inclusion if they reported qualitatively on GPs' diagnosis or treatment of perinatal anxiety or depression. The synthesis was constructed using meta-ethnography. Five themes were established from five eligible papers: labels: diagnosing depression; clinical judgement versus guidelines; care and management; use of medication; and isolation: the role of other professionals. GPs considered perinatal depression to be a psychosocial phenomenon, and were reluctant to label disorders and medicalise distress. GPs relied on their own clinical judgement more than guidelines. They reported helping patients make informed choices about treatment, and inviting them back regularly for GP visits. GPs sometimes felt isolated when dealing with perinatal mental health issues. GPs often do not have timely access to appropriate psychological therapies and use several strategies to mitigate this shortfall. Training must focus on these issues and must be evaluated to consider whether this makes a difference to outcomes for patients. © British Journal of General Practice 2017.

Association between the COMT Val158Met polymorphism and fibromyalgia susceptibility and fibromyalgia impact questionnaire score: a meta-analysis.

PubMed

Lee, Young Ho; Kim, Jae-Hoon; Song, Gwan Gyu

2015-01-01

The aim of this study was to explore whether the catechol-O-methyltransferase (COMT) Val158Met polymorphism is associated with susceptibility to fibromyalgia and fibromyalgia impact questionnaire (FIQ) score in fibromyalgia patients. We conducted a meta-analysis of the associations of the COMT Val158Met polymorphism with fibromyalgia risk as well as FIQ score in fibromyalgia patients. A total of 993 fibromyalgia patients and 778 controls from 10 studies on the COMT Val158Met polymorphism and 538 fibromyalgia patients from 5 studies on the COMT Val158Met polymorphism and FIQ score were included in this meta-analysis. The meta-analysis revealed an association between fibromyalgia and the COMT Met/Met + Val/Met genotype in all study subjects (odds ratio (OR) 1.635, 95 % confidence interval (CI) 1.029-2.597, p = 0.037). However, stratification by ethnicity indicated no association between the Met/Met + Val/Met genotype and fibromyalgia in the European and Turkish populations (OR 1.202, 95 % CI 0.876-1.649, p = 0.255; OR 2.132, 95 % CI 0.764-5.949, p = 0.148, respectively). Analysis using other genetic models showed no association between the COMT Val158Met polymorphism and fibromyalgia. The meta-analysis also revealed that the FIQ score was significantly higher in individuals with the COMT Met/Met genotype than in those with the Val/Val genotype [weighted mean difference (WMD) = 14.39, 95 % CI 3.316-25.48, p = 0.011] and the Val/Met genotype (WMD = 5.108, 95 % CI 2.212-4.891, p = 0.021). This meta-analysis identified an association between fibromyalgia risk and the COMT Val158Met polymorphism as well as the FIQ score in fibromyalgia patients.

Prevalence of hyperphagia in Alzheimer's disease: a meta-analysis.

PubMed

Shea, Yat-Fung; Lee, Shui-Ching; Chu, Leung-Wing

2018-02-06

Unlike other behavioural and psychological symptoms of dementia, hyperphagia is less recognized among patients with Alzheimer's disease (AD). The prevalence of hyperphagia varies among studies, but there has been no systematic review or meta-analysis. An extensive search on the literature on hyperphagia in AD published between 1 January 1980 and 30 October 2017 was conducted. Data on the prevalence were retrieved. Meta-analysis with a random effect model was performed to determine the pooled estimate of prevalence. Meta-regression analysis was performed based on study characteristics, population demographics, or condition information. Results from 20 studies were extracted. Twenty-six reported cases of hyperphagia were identified. The mean age of onset was 70.7 ± 8.9 years, with a male predominance (68.4%). Hyperphagia occurred in all stages of AD. Only eight studies reported the prevalence of hyperphagia. Meta-analysis showed a pooled prevalence of hyperphagia of 18.6%. Publication bias may have been present. Meta-regression showed that ethnicity accounted for the variance among studies (coefficient: -1.247 (95% confidence interval: -1.978 to -0.516), R 2 analogue: 0.77, P < 0.001). Hyperphagia occurs in all stages of AD. In this meta-analysis of eight published studies, the prevalence of hyperphagia was 18.6%. In view of the possible publication bias, a large-scale study on hyperphagia is recommended in the future. © 2018 Japanese Psychogeriatric Society.

A meta-analysis of the effects of β-adrenergic blockers in chronic heart failure.

PubMed

Zhang, Xiaojian; Shen, Chengwu; Zhai, Shujun; Liu, Yukun; Yue, Wen-Wei; Han, Li

2016-10-01

Adrenergic β-blockers are drugs that bind to, but do not activate β-adrenergic receptors. Instead they block the actions of β-adrenergic agonists and are used for the treatment of various diseases such as cardiac arrhythmias, angina pectoris, myocardial infarction, hypertension, headache, migraines, stress, anxiety, prostate cancer, and heart failure. Several meta-analysis studies have shown that β-blockers improve the heart function and reduce the risks of cardiovascular events, rate of mortality, and sudden death through chronic heart failure (CHF) of patients. The present study identified results from recent meta-analyses of β-adrenergic blockers and their usefulness in CHF. Databases including Medline/Embase/Cochrane Central Register of Controlled Trials (CENTRAL), and PubMed were searched for the periods May, 1985 to March, 2011 and June, 2013 to August, 2015, and a number of studies identified. Results of those studies showed that use of β-blockers was associated with decreased sudden cardiac death in patients with heart failure. However, contradictory results have also been reported. The present meta-analysis aimed to determine the efficacy of β-blockers on mortality and morbidity in patients with heart failure. The results showed that mortality was significantly reduced by β-blocker treatment prior to the surgery of heart failure patients. The results from the meta-analysis studies showed that β-blocker treatment in heart failure patients correlated with a significant decrease in long-term mortality, even in patients that meet one or more exclusion criteria of the MERIT-HF study. In summary, the findings of the current meta-analysis revealed beneficial effects different β-blockers have on patients with heart failure or related heart disease.

A meta-analysis of the effects of β-adrenergic blockers in chronic heart failure

PubMed Central

Zhang, Xiaojian; Shen, Chengwu; Zhai, Shujun; Liu, Yukun; Yue, Wen-Wei; Han, Li

2016-01-01

Adrenergic β-blockers are drugs that bind to, but do not activate β-adrenergic receptors. Instead they block the actions of β-adrenergic agonists and are used for the treatment of various diseases such as cardiac arrhythmias, angina pectoris, myocardial infarction, hypertension, headache, migraines, stress, anxiety, prostate cancer, and heart failure. Several meta-analysis studies have shown that β-blockers improve the heart function and reduce the risks of cardiovascular events, rate of mortality, and sudden death through chronic heart failure (CHF) of patients. The present study identified results from recent meta-analyses of β-adrenergic blockers and their usefulness in CHF. Databases including Medline/Embase/Cochrane Central Register of Controlled Trials (CENTRAL), and PubMed were searched for the periods May, 1985 to March, 2011 and June, 2013 to August, 2015, and a number of studies identified. Results of those studies showed that use of β-blockers was associated with decreased sudden cardiac death in patients with heart failure. However, contradictory results have also been reported. The present meta-analysis aimed to determine the efficacy of β-blockers on mortality and morbidity in patients with heart failure. The results showed that mortality was significantly reduced by β-blocker treatment prior to the surgery of heart failure patients. The results from the meta-analysis studies showed that β-blocker treatment in heart failure patients correlated with a significant decrease in long-term mortality, even in patients that meet one or more exclusion criteria of the MERIT-HF study. In summary, the findings of the current meta-analysis revealed beneficial effects different β-blockers have on patients with heart failure or related heart disease. PMID:27703506

Is Ginkgo biloba a cognitive enhancer in healthy individuals? A meta-analysis.

PubMed

Laws, Keith R; Sweetnam, Hilary; Kondel, Tejinder K

2012-11-01

We conducted a meta-analysis to examine whether Ginkgo biloba (G. biloba) enhances cognitive function in healthy individuals. Scopus, Medline, Google Scholar databases and recent qualitative reviews were searched for studies examining the effects of G. biloba on cognitive function in healthy individuals. We identified randomised controlled trials containing data on memory (K = 13), executive function (K = 7) and attention (K = 8) from which effect sizes could be derived. The analyses provided measures of memory, executive function and attention in 1132, 534 and 910 participants, respectively. Effect sizes were non-significant and close to zero for memory (d = -0.04: 95%CI -0.17 to 0.07), executive function (d = -0.05: 95%CI -0.17 to 0.05) and attention (d = -0.08: 95%CI -0.21 to 0.02). Meta-regressions showed that effect sizes were not related to participant age, duration of the trial, daily dose, total dose or sample size. We report that G. biloba had no ascertainable positive effects on a range of targeted cognitive functions in healthy individuals. Copyright © 2012 John Wiley & Sons, Ltd.

Residual disease at the bronchial stump is positively associated with the risk of bronchoplerual fistula in patients undergoing lung cancer surgery: a meta-analysis

PubMed Central

Li, Shuangjiang; Fan, Jun; Zhou, Jian; Ren, Yutao; Shen, Cheng; Che, Guowei

2016-01-01

OBJECTIVES Residual disease at the bronchial stump (RDBS) is regarded as an important factor possibly resulting in bronchopleural fistula (BPF) after lung cancer surgery, but this has not been confirmed. We conducted this meta-analysis to evaluate the effects of RDBS on BPF formation in patients undergoing lung cancer surgery. METHODS PubMed and EMBASE databases were searched for full-text articles that met our eligibility criteria. Odds ratios (ORs) with 95% confidence interval (95% CI) served as the summarized outcomes. Q-test and I2 statistic were used to evaluate the level of heterogeneity, determining the fixed-effect model or random-effect model for quantitative synthesis. Sensitivity analysis was conducted to identify the possible origins of heterogeneity. The publication bias was assessed by Begg's test. RESULTS A total of eight retrospective observational studies were included in our meta-analysis. In overall analysis, the pooled outcomes indicated that RDBS was significantly associated with BPF formation after lung cancer surgery (OR: 3.12; 95% CI: 1.72–5.64; P < 0.001). In subgroup analysis, the pooled outcomes revealed a significantly increased risk of post-pneumonectomy BPF in patients with RDBS (OR: 2.78; 95% CI: 1.06–7.28; P = 0.037). The subgroup analysis assessing the effects of RDBS on post-lobectomy BPF was given up due to the scarcity of available data. No heterogeneity was revealed within this meta-analysis. No evidence for publication bias was detected by Begg's test. CONCLUSIONS Our meta-analysis indicates that RDBS is positively associated with the increased risk of BPF in patients undergoing lung cancer surgery. The further analysis also reveals an increased risk of post-pneumonectomy BPF in patients with RDBS. More accurate and comprehensive evidence should be collected and summarized in updated meta-analyses. PMID:26614527

Qualitative data analysis: conceptual and practical considerations.

PubMed

Liamputtong, Pranee

2009-08-01

Qualitative inquiry requires that collected data is organised in a meaningful way, and this is referred to as data analysis. Through analytic processes, researchers turn what can be voluminous data into understandable and insightful analysis. This paper sets out the different approaches that qualitative researchers can use to make sense of their data including thematic analysis, narrative analysis, discourse analysis and semiotic analysis and discusses the ways that qualitative researchers can analyse their data. I first discuss salient issues in performing qualitative data analysis, and then proceed to provide some suggestions on different methods of data analysis in qualitative research. Finally, I provide some discussion on the use of computer-assisted data analysis.

Influence of rumen protozoa on methane emission in ruminants: a meta-analysis approach.

PubMed

Guyader, J; Eugène, M; Nozière, P; Morgavi, D P; Doreau, M; Martin, C

2014-11-01

A meta-analysis was conducted to evaluate the effects of protozoa concentration on methane emission from ruminants. A database was built from 59 publications reporting data from 76 in vivo experiments. The experiments included in the database recorded methane production and rumen protozoa concentration measured on the same groups of animals. Quantitative data such as diet chemical composition, rumen fermentation and microbial parameters, and qualitative information such as methane mitigation strategies were also collected. In the database, 31% of the experiments reported a concomitant reduction of both protozoa concentration and methane emission (g/kg dry matter intake). Nearly all of these experiments tested lipids as methane mitigation strategies. By contrast, 21% of the experiments reported a variation in methane emission without changes in protozoa numbers, indicating that methanogenesis is also regulated by other mechanisms not involving protozoa. Experiments that used chemical compounds as an antimethanogenic treatment belonged to this group. The relationship between methane emission and protozoa concentration was studied with a variance-covariance model, with experiment as a fixed effect. The experiments included in the analysis had a within-experiment variation of protozoa concentration higher than 5.3 log10 cells/ml corresponding to the average s.e.m. of the database for this variable. To detect potential interfering factors for the relationship, the influence of several qualitative and quantitative secondary factors was tested. This meta-analysis showed a significant linear relationship between methane emission and protozoa concentration: methane (g/kg dry matter intake)=-30.7+8.14×protozoa (log10 cells/ml) with 28 experiments (91 treatments), residual mean square error=1.94 and adjusted R 2=0.90. The proportion of butyrate in the rumen positively influenced the least square means of this relationship.

Meta-analysis: An Approach to the Synthesis of Research Results.

ERIC Educational Resources Information Center

Glass, Gene V.

1982-01-01

Discusses three general characteristics and four criticisms of meta-analysis (statistical analysis of the summary findings of many research studies). Illustrates application of meta-analysis on research studies relating to school class size and achievement and inquiry teaching of biology. (JN)

Gene Level Meta-Analysis of Quantitative Traits by Functional Linear Models.

PubMed

Fan, Ruzong; Wang, Yifan; Boehnke, Michael; Chen, Wei; Li, Yun; Ren, Haobo; Lobach, Iryna; Xiong, Momiao

2015-08-01

Meta-analysis of genetic data must account for differences among studies including study designs, markers genotyped, and covariates. The effects of genetic variants may differ from population to population, i.e., heterogeneity. Thus, meta-analysis of combining data of multiple studies is difficult. Novel statistical methods for meta-analysis are needed. In this article, functional linear models are developed for meta-analyses that connect genetic data to quantitative traits, adjusting for covariates. The models can be used to analyze rare variants, common variants, or a combination of the two. Both likelihood-ratio test (LRT) and F-distributed statistics are introduced to test association between quantitative traits and multiple variants in one genetic region. Extensive simulations are performed to evaluate empirical type I error rates and power performance of the proposed tests. The proposed LRT and F-distributed statistics control the type I error very well and have higher power than the existing methods of the meta-analysis sequence kernel association test (MetaSKAT). We analyze four blood lipid levels in data from a meta-analysis of eight European studies. The proposed methods detect more significant associations than MetaSKAT and the P-values of the proposed LRT and F-distributed statistics are usually much smaller than those of MetaSKAT. The functional linear models and related test statistics can be useful in whole-genome and whole-exome association studies. Copyright © 2015 by the Genetics Society of America.

The role of schools in children and young people's self-harm and suicide: systematic review and meta-ethnography of qualitative research.

PubMed

Evans, Rhiannon; Hurrell, Chloe

2016-05-14

Evidence reports that schools influence children and young people's health behaviours across a range of outcomes. However there remains limited understanding of the mechanisms through which institutional features may structure self-harm and suicide. This paper reports on a systematic review and meta-ethnography of qualitative research exploring how schools influence self-harm and suicide in students. Systematic searches were conducted of nineteen databases from inception to June 2015. English language, primary research studies, utilising any qualitative research design to report on the influence of primary or secondary educational settings (or international equivalents) on children and young people's self-harm and suicide were included. Two reviewers independently appraised studies against the inclusion criteria, assessed quality, and abstracted data. Data synthesis was conducted in adherence with Noblit and Hare's meta-ethnographic approach. Of 6744 unique articles identified, six articles reporting on five studies were included in the meta-ethnography. Five meta-themes emerged from the studies. First, self-harm is often rendered invisible within educational settings, meaning it is not prioritised within the curriculum despite students' expressed need. Second, where self-harm transgresses institutional rules it may be treated as 'bad behaviour', meaning adequate support is denied. Third, schools' informal management strategy of escalating incidents of self-harm to external 'experts' serves to contribute to non-help seeking behaviour amongst students who desire confidential support from teachers. Fourth, anxiety and stress associated with school performance may escalate self-harm and suicide. Fifth, bullying within the school context can contribute to self-harm, whilst some young people may engage in these practices as initiation into a social group. Schools may influence children and young people's self-harm, although evidence of their impact on suicide remains

Neither fixed nor random: weighted least squares meta-analysis.

PubMed

Stanley, T D; Doucouliagos, Hristos

2015-06-15

This study challenges two core conventional meta-analysis methods: fixed effect and random effects. We show how and explain why an unrestricted weighted least squares estimator is superior to conventional random-effects meta-analysis when there is publication (or small-sample) bias and better than a fixed-effect weighted average if there is heterogeneity. Statistical theory and simulations of effect sizes, log odds ratios and regression coefficients demonstrate that this unrestricted weighted least squares estimator provides satisfactory estimates and confidence intervals that are comparable to random effects when there is no publication (or small-sample) bias and identical to fixed-effect meta-analysis when there is no heterogeneity. When there is publication selection bias, the unrestricted weighted least squares approach dominates random effects; when there is excess heterogeneity, it is clearly superior to fixed-effect meta-analysis. In practical applications, an unrestricted weighted least squares weighted average will often provide superior estimates to both conventional fixed and random effects. Copyright © 2015 John Wiley & Sons, Ltd.

Hypothyroidism and carpal tunnel syndrome: a meta-analysis.

PubMed

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.

Aripiprazole and Acute Extrapyramidal Symptoms in Children and Adolescents: A Meta-Analysis.

PubMed

Bernagie, Chiara; Danckaerts, Marina; Wampers, Martien; De Hert, Marc

2016-09-01

Both the US FDA and the European Medicines Agency (EMA) have approved aripiprazole for use in adolescents for specific indications. Given the assumed favorable side-effect profile of aripiprazole, its use in children and adolescents has increased for both official and off-label indications (anxiety disorders, eating disorders, personality disorders). However, several cases of children and adolescents with new-onset extrapyramidal symptoms (EPS) after commencing treatment with aripiprazole have been reported, and a more systematic appraisal of this possible risk is lacking. We conducted a systematic review and a meta-analysis to assess the evidence for acute EPS (acute dystonia, akathisia, Parkinsonism) associated with the use of aripiprazole in children and adolescents. We searched the MEDLINE and Embase databases (2003-10 April 2016) for clinical trials in pediatric patients (aged 0-18 years) using the keywords 'aripiprazole' (regardless of the formulation) and 'extrapyramidal symptoms'. We evaluated the abstracts of papers using the following exclusion criteria: (1) study design: case report, letter to the editor, editorial, or poster presentation data; (2) unrelated PICOS (population, intervention, comparators, outcomes, study) structure. We performed a meta-analysis, in which we used effect sizes with 95 % confidence intervals (CIs). To examine the homogeneity of the effect size distribution, we used a Q-statistic. When we observed heterogeneity in effect sizes, we assessed the possible influence of moderator variables (age and sex, mean dose, study duration, and method of measuring EPS incidence) and evaluated the suitability of either a fixed or a random model. Finally, we assessed the incidence of EPS in children and adolescents treated with aripiprazole compared with placebo. An initial search via PubMed and Embase yielded 328 hits. A manual search of the reference lists of review papers revealed seven additional relevant articles. We included 41 studies

Mismatch Negativity in Han Chinese Patients with Schizophrenia: A Meta-Analysis.

PubMed

Xiong, Yanbing; Ll, Xianbin; Zhao, Lei; Wang, Chuanyue

2017-10-25

Previous meta-analysis revealed that mismatch negativity(MMN) amplitude decreased in patients with schizophrenia compared with healthy controls (Cohen's d, d about 1), leading to the possibility of mismatch negativity being used as a biomarker for schizophrenia. However, it is unknown whether MMN is reliably changed in Chinese patients. It is necessary to carry out a meta-analysis on MMN of Han Chinese patients with schizophrenia. To investigate whether MMN could be used as a biomarker for Han Chinese patients with schizophrenia. A literature search was conducted to identify clinical trials on MMN in Han Chinese schizophrenia patients published before May 8, 2017, by searching the Chinese language databases CNKI, WanFang Data, VIP Data and PubMed. The effects of MMN deficits were evaluated for MMN amplitude by calculating standard mean difference (SMDs) between schizophrenia patient groups and healthy control groups. A total of 11 studies were included in the analysis. The total quality of all the studies were more than 6 as evaluated by Newcastle-Ottawa Scale (NOS). Meta-analysis of data from these studies had a pooled sample of 432 patients with schizophrenia and 392 healthy controls. There exists significant MMN deficit in schizophrenia patients compared to healthy controls (Cohen's d =1.004). When studies were excluded due to heterogeneity, the pooled effect size of the MMN differences between the patient group and healthy controls dropped to 0.79 (Cohen's d =0.79). Subgroup analysis showed that MMN amplitude deficits of schizophrenia over three years had the pooled effect size of 0.95, and less than three years had the pooled effect size of 0.77. Publication bias conducted via Egger regression test ( t = 1.83; p = 0.101), suggested that there was no publication bias. The effect size of MMN amplitude between Chinese patients with schizophrenia and healthy controls is consistent with other meta-analyses published on this topic, suggesting that Han Chinese

Effect of exercise on cognitive function in chronic disease patients: a meta-analysis and systematic review of randomized controlled trials.

PubMed

Cai, Hong; Li, Guichen; Hua, Shanshan; Liu, Yufei; Chen, Li

2017-01-01

The purpose of this study was to conduct a meta-analysis and systematic review to assess the effect of exercise on cognitive function in people with chronic diseases. PubMed, Web of Science, Embase, the Cochrane Library, CINAHL, PsycINFO, and three Chinese databases were electronically searched for papers that were published until September 2016. This meta-analysis and systematic review included randomized controlled trials that evaluated the effect of exercise on cognitive function compared with control group for people with chronic diseases. Totally, 35 studies met the inclusion criteria, with 3,113 participants. The main analysis revealed a positive overall random effect of exercise intervention on cognitive function in patients with chronic diseases. The secondary analysis revealed that aerobic exercise interventions and aerobic included exercise interventions had a positive effect on cognition in patients with chronic diseases. The intervention offering low frequency had a positive effect on cognitive function in patients with chronic diseases. Finally, we found that interventions offered at both low exercise intensity and moderate exercise intensity had a positive effect on cognitive function in patients with chronic diseases. The secondary analysis also revealed that exercise interventions were beneficial in Alzheimer's disease patients when grouped by disease type. This meta-analysis and systematic review suggests that exercise interventions positively influence cognitive function in patients with chronic diseases. Beneficial effect was independent of the type of disease, type of exercise, frequency, and the intensity of the exercise intervention.

Effect of exercise on cognitive function in chronic disease patients: a meta-analysis and systematic review of randomized controlled trials

PubMed Central

Cai, Hong; Li, Guichen; Hua, Shanshan; Liu, Yufei; Chen, Li

2017-01-01

Background The purpose of this study was to conduct a meta-analysis and systematic review to assess the effect of exercise on cognitive function in people with chronic diseases. Methods PubMed, Web of Science, Embase, the Cochrane Library, CINAHL, PsycINFO, and three Chinese databases were electronically searched for papers that were published until September 2016. This meta-analysis and systematic review included randomized controlled trials that evaluated the effect of exercise on cognitive function compared with control group for people with chronic diseases. Results Totally, 35 studies met the inclusion criteria, with 3,113 participants. The main analysis revealed a positive overall random effect of exercise intervention on cognitive function in patients with chronic diseases. The secondary analysis revealed that aerobic exercise interventions and aerobic included exercise interventions had a positive effect on cognition in patients with chronic diseases. The intervention offering low frequency had a positive effect on cognitive function in patients with chronic diseases. Finally, we found that interventions offered at both low exercise intensity and moderate exercise intensity had a positive effect on cognitive function in patients with chronic diseases. The secondary analysis also revealed that exercise interventions were beneficial in Alzheimer’s disease patients when grouped by disease type. Conclusion This meta-analysis and systematic review suggests that exercise interventions positively influence cognitive function in patients with chronic diseases. Beneficial effect was independent of the type of disease, type of exercise, frequency, and the intensity of the exercise intervention. PMID:28546744

Sleep duration and obesity in children: A systematic review and meta-analysis of prospective cohort studies.

PubMed

Li, Lian; Zhang, Shuang; Huang, Yubei; Chen, Kexin

2017-04-01

Childhood obesity is a major public problem worldwide, and sleep duration may be associated with childhood obesity. We conducted a systematic review and meta-analysis of prospective cohort studies to estimate the associations between sleep duration and obesity/body mass index (BMI) in children. PubMed, Embase and the Cochrane Library were searched. For the meta-analysis, the pooled relative risk (RR) and 95% confidence intervals (CI) were estimated to reveal the association between short sleep duration and obesity. For the review, the outcomes focused on BMI change or subsequent BMI status. A total of 12 studies (15 populations) met the criteria for inclusion in the meta-analysis. Short sleep duration was significantly associated with obesity (RR: 1.45; 95% CI: 1.14-1.85). After excluding two cohorts that substantially affected the heterogeneity, the pooled results remained significant (RR: 1.30; 95% CI: 1.20-1.42), and the association was not substantially altered in the subgroup analysis. In addition, we summarised 24 studies that met the criteria for our review of the relationship between sleeping and BMI. The present meta-analysis indicated that short sleep duration increased the risk of childhood obesity. Public health efforts that encourage children to have sufficient sleep time may be important in combating obesity. © 2017 Paediatrics and Child Health Division (The Royal Australasian College of Physicians).

Prognostic value of lncRNAs in lung carcinoma: a meta-analysis.

PubMed

Fan, Fan; Zhu, Zhengqiu; Gao, Chao; Liu, Yun; Wang, Baoqing; Wang, Ziquan; Feng, Jifeng

2017-10-10

Many different long non-coding RNAs (lncRNAs) have been reported to be abnormally expressed in lung carcinoma and may thus serve as prognostic biomarkers for this disease. We conducted this meta-analysis, which included a total of 30 studies identified via searches of PubMed, Embase, Medline, and Web of Science and included 2912 patients from China (28), Germany (1), and Japan (1), to investigate the prognostic value of different lncRNAs in lung carcinoma. The results revealed that lncRNA transcription levels were significantly associated with overall survival in lung cancer patients (HR:1.46, 95% CI: 1.16-1.83, P = 0.000). However, lncRNA transcription levels were not associated with progression-free survival (PFS) (HR: 1.55, 95% CI: 0.50-4.80, P = 0.449). Further analysis showed that high lncRNA transcription levels were significantly associated with tumour-node-metastasis (TNM) stage (III/IV vs I/II: RR = 1.339, 95% CI: 1.046-1.716, P = 0.012), lymph node metastasis (positive vs negative: RR = 1.442, 95% CI: 1.103-1.885, P = 0.007), and distant metastasis (yes vs no: RR = 3.187,95% CI: 1.393-7.294, P = 0.006). Taken together, the results of our present meta-analysis revealed that lncRNAs may be useful prognostic markers for lung carcinoma and may also have value as biomarkers for TNM stage, lymph node metastasis and distant metastasis.

Prognostic value of lncRNAs in lung carcinoma: a meta-analysis

PubMed Central

Fan, Fan; Zhu, Zhengqiu; Gao, Chao; Liu, Yun; Wang, Baoqing; Wang, Ziquan; Feng, Jifeng

2017-01-01

Many different long non-coding RNAs (lncRNAs) have been reported to be abnormally expressed in lung carcinoma and may thus serve as prognostic biomarkers for this disease. We conducted this meta-analysis, which included a total of 30 studies identified via searches of PubMed, Embase, Medline, and Web of Science and included 2912 patients from China (28), Germany (1), and Japan (1), to investigate the prognostic value of different lncRNAs in lung carcinoma. The results revealed that lncRNA transcription levels were significantly associated with overall survival in lung cancer patients (HR:1.46, 95% CI: 1.16–1.83, P = 0.000). However, lncRNA transcription levels were not associated with progression-free survival (PFS) (HR: 1.55, 95% CI: 0.50–4.80, P = 0.449). Further analysis showed that high lncRNA transcription levels were significantly associated with tumour-node-metastasis (TNM) stage (III/IV vs I/II: RR = 1.339, 95% CI: 1.046–1.716, P = 0.012), lymph node metastasis (positive vs negative: RR = 1.442, 95% CI: 1.103–1.885, P = 0.007), and distant metastasis (yes vs no: RR = 3.187,95% CI: 1.393–7.294, P = 0.006). Taken together, the results of our present meta-analysis revealed that lncRNAs may be useful prognostic markers for lung carcinoma and may also have value as biomarkers for TNM stage, lymph node metastasis and distant metastasis. PMID:29137343

Understanding the management and teaching of dental restoration repair: Systematic review and meta-analysis of surveys.

PubMed

Kanzow, Philipp; Wiegand, Annette; Göstemeyer, Gerd; Schwendicke, Falk

2018-02-01

Repair instead of complete replacement is recommended to manage partially defective restorations. It is unclear if and why such treatment is taught at dental schools or practiced by dentists. We aimed to identify barriers and facilitators for repairs using a systematic review and meta- and qualitative analysis. Electronic databases (PubMed, CENTRAL, Embase, PsycINFO) were searched. Quantitative studies reporting on the proportion of (1) dentists stating to perform repairs, (2) dental schools teaching repairs, (3) failed restorations having been repaired were included. We also included qualitative studies on barriers/facilitators for repairs. Random-effects meta-analyses, meta-regression and a thematic analysis using the theoretical domains framework were conducted. 401 articles were assessed and 29, mainly quantitative, studies included. 7228 dentists and 276 dental schools had been surveyed, and treatment data of 30,172 restorations evaluated. The mean (95% CI) proportion of dentists stating to perform repairs was 71.5% (49.7-86.4%). 83.3% (73.6-90.0%) of dental schools taught repairs. 31.3% (26.3-36.7%) of failed restorations had been repaired. More recent studies reported significantly more dentists to repair restorations (p=0.004). Employment in public health practices and being the dentist who placed the original restoration were facilitators for repairs. Amalgam restorations were repaired less often, and financial aspects and regulations came as barriers. While most dentists state to perform repairs and the vast majority of dental schools teach repairs, the proportion of truly repaired restorations was low. A number of interventions to implement repair in dental practice can be deduced from our findings. Partially defective restorations are common in dental practice. While repairs are taught and dentists are aware of the recommendation towards repairs, the actually performed proportion of repairs seems low. Copyright © 2017 Elsevier Ltd. All rights reserved.

Human 8-oxoguanine DNA glycosylase gene polymorphism (Ser326Cys) and cancer risk: updated meta-analysis

PubMed Central

Park, Hae Jeong; Chung, Joo-Ho; Ban, Ju Yeon

2017-01-01

Genetic polymorphism of human 8-oxoguanine glycosylase 1 (hOGG1) has been reported to have a relationship with the risk of the development of various cancers. Many studies have described the influence of Ser326Cys polymorphism of the hOGG1 gene on cancer susceptibility. However, the results have remained inconclusive and controversial. Therefore, we performed a meta-analysis to more precisely determine the relationship between the hOGG1 polymorphism and the development of cancer. Electronic databases including PubMed, Embase, Google Scholar, and the Korean Studies Information Service System (KISS) were searched. The odds ratio (OR), 95% confidence interval (CI), and p value were calculated to assess the strength of the association with the risk of cancer using Comprehensive Meta-analysis software (Corporation, NJ, USA). The 127 studies including 38,757 cancer patients and 50,177 control subjects were analyzed for the meta-analysis. Our meta-analysis revealed that G allele of Ser326Cys polymorphism of the hOGG1 gene statistically increased the susceptibility of cancer (all population, OR = 1.092, 95% CI = 1.051-1.134, p < 0.001; in Asian, OR = 1.095, 95% CI = 1.048-1.145, p < 0.001; in Caucasian, OR = 1.097, 95% CI = 1.033-1.179, p = 0.002). Also, other genotype models showed significant association with cancer (p < 0.05, respectively). The present meta-analysis concluded that the G allele was associated with an increased risk of cancer. It suggested that the hOGG1 polymorphism may be a candidate marker of cancer. PMID:28415770

Human Fear Chemosignaling: Evidence from a Meta-Analysis.

PubMed

de Groot, Jasper H B; Smeets, Monique A M

2017-10-01

Alarm pheromones are widely used in the animal kingdom. Notably, there are 26 published studies (N = 1652) highlighting a human capacity to communicate fear, stress, and anxiety via body odor from one person (66% males) to another (69% females). The question is whether the findings of this literature reflect a true effect, and what the average effect size is. These questions were answered by combining traditional meta-analysis with novel meta-analytical tools, p-curve analysis and p-uniform-techniques that could indicate whether findings are likely to reflect a true effect based on the distribution of P-values. A traditional random-effects meta-analysis yielded a small-to-moderate effect size (Hedges' g: 0.36, 95% CI: 0.31-0.41), p-curve analysis showed evidence diagnostic of a true effect (ps < 0.0001), and there was no evidence for publication bias. This meta-analysis did not assess the internal validity of the current studies; yet, the combined results illustrate the statistical robustness of a field in human olfaction dealing with the human capacity to communicate certain emotions (fear, stress, anxiety) via body odor. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

A systematic review and meta-ethnography of the qualitative literature: experiences of the menarche.

PubMed

Chang, Yu-Ting; Hayter, Mark; Wu, Shu-Chen

2010-02-01

This article is a report of a systematic review and meta-ethnography of women's experience of menarche. Adolescents may experience menarche at different ages, but menarche remains an important milestone in the female maturation process, representing the transition from childhood to womanhood. Systematic review and meta-ethnography. Electronic databases were systematically searched and supplemented with reference lists searching. Qualitative studies of women's experience of menarche were purposely selected and questions proposed by the critical appraisal skills programme was adapted and used to assess papers prior to synthesis. Key themes and concepts were extracted and synthesised using meta-ethnography. Fourteen studies on menarche experience were identified. The majority of studies were descriptive. Five key concepts were identified from all 14 papers as being descriptive of women's experience of menarche. These included: menarche preparation, significant others' response to menarche, physical experience of menarche, psychological experience of menarche and social-cultural perspective of menarche. Menarche experience had a major impact on women. Women went through physical, psychological and social-culture changes when their first menstrual flow came. Menarche preparation has been shown to have a beneficial impact on the menarcheal woman. School nurses have accurate knowledge about sexual health; they can and should provide appropriate menstrual education. The findings can be used by school nurses working with adolescents as the basis for a framework of intervention strategies directed towards helping adolescents to better accept their menarche and transition into womanhood.

A Meta-Analysis of Hodgkin Lymphoma Reveals 19p13.3 TCF3 as a Novel Susceptibility Locus

PubMed Central

Cozen, W; Timofeeva, MN; Li, D; Diepstra, A; Hazelett, D; Delahaye-Sourdeix, M; Edlund, CK; Franke, L; Rostgaard, K; Van Den Berg, DJ; Cortessis, VK; Smedby, KE; Glaser, SL; H-J, Westra; Robison, LL; Mack, TM; Ghesquieres, H; Hwang, AE; Nieters, A; de Sanjose, S; Lightfoot, T; Becker, N; Maynadie, M; Foretova, L; Roman, E; Benavente, Y; Rand, KA; Nathwani, BN; Glimelius, B; Staines, A; Boffetta, P; Link, BK; Kiemeney, L; Ansell, SM; Bhatia, S; Strong, LC; Galan, P; Vatten, L; Habermann, TM; Duell, EJ; Lake, A; Veenstra, RN; Visser, L; Liu, Y; Urayama, KY; Montgomery, D; Gaborieau, V; Weiss, LM; Byrnes, G; Lathrop, M; Cocco, P; Best, T; Skol, AD; H-O, Adami; Melbye, M; Cerhan, JR; Gallagher, A; Taylor, GM; Slager, SL; Brennan, P; Coetzee, GA; Conti, DV; Onel, K; Jarrett, RF; Hjalgrim, H; van den Berg, A; McKay, JD

2014-01-01

Recent genome wide association studies (GWAS) of Hodgkin lymphoma (HL) have identified associations with genetic variation at both HLA and non-HLA loci; however, much of heritable HL susceptibility remains unexplained. Here we perform a meta-analysis of three HL GWAS totaling 1,816 cases and 7,877 controls followed by replication in an independent set of 1,281 cases and 3,218 controls to find novel risk loci. We identify a novel variant at 19p13.3 associated with HL (rs1860661; odds ratio [OR] = 0.81, 95% confidence interval [95% CI] = 0.76–0.86, Pcombined = 3.5 × 10−10), located in intron 2 of TCF3 (also known as E2A), a regulator of B- and T-cell lineage commitment known to be involved in HL pathogenesis. This meta-analysis also notes associations between previously published loci at 2p16.1, 5q31, 6p31.2, 8q24.21 and 10p14 and HL subtypes. We conclude that our data suggest a link between the 19p13.3 locus, including TCF3, and HL risk PMID:24920014

Multivariate meta-analysis for non-linear and other multi-parameter associations

PubMed Central

Gasparrini, A; Armstrong, B; Kenward, M G

2012-01-01

In this paper, we formalize the application of multivariate meta-analysis and meta-regression to synthesize estimates of multi-parameter associations obtained from different studies. This modelling approach extends the standard two-stage analysis used to combine results across different sub-groups or populations. The most straightforward application is for the meta-analysis of non-linear relationships, described for example by regression coefficients of splines or other functions, but the methodology easily generalizes to any setting where complex associations are described by multiple correlated parameters. The modelling framework of multivariate meta-analysis is implemented in the package mvmeta within the statistical environment R. As an illustrative example, we propose a two-stage analysis for investigating the non-linear exposure–response relationship between temperature and non-accidental mortality using time-series data from multiple cities. Multivariate meta-analysis represents a useful analytical tool for studying complex associations through a two-stage procedure. Copyright © 2012 John Wiley & Sons, Ltd. PMID:22807043

Task modulated brain connectivity of the amygdala: a meta-analysis of psychophysiological interactions.

PubMed

Di, Xin; Huang, Jia; Biswal, Bharat B

2017-01-01

Understanding functional connectivity of the amygdala with other brain regions, especially task modulated connectivity, is a critical step toward understanding the role of the amygdala in emotional processes and the interactions between emotion and cognition. The present study performed coordinate-based meta-analysis on studies of task modulated connectivity of the amygdala which used psychophysiological interaction (PPI) analysis. We first analyzed 49 PPI studies on different types of tasks using activation likelihood estimation (ALE) meta-analysis. Widespread cortical and subcortical regions showed consistent task modulated connectivity with the amygdala, including the medial frontal cortex, bilateral insula, anterior cingulate, fusiform gyrus, parahippocampal gyrus, thalamus, and basal ganglia. These regions were in general overlapped with those showed coactivations with the amygdala, suggesting that these regions and amygdala are not only activated together, but also show different levels of interactions during tasks. Further analyses with subsets of PPI studies revealed task specific functional connectivities with the amygdala that were modulated by fear processing, face processing, and emotion regulation. These results suggest a dynamic modulation of connectivity upon task demands, and provide new insights on the functions of the amygdala in different affective and cognitive processes. The meta-analytic approach on PPI studies may offer a framework toward systematical examinations of task modulated connectivity.

CrossFit Overview: Systematic Review and Meta-analysis.

PubMed

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.

[Basic concepts for network meta-analysis].

PubMed

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

2014-12-01

Systematic reviews and meta-analyses have long been fundamental tools for evidence-based clinical practice. Initially, meta-analyses were proposed as a technique that could improve the accuracy and the statistical power of previous research from individual studies with small sample size. However, one of its main limitations has been the fact of being able to compare no more than two treatments in an analysis, even when the clinical research question necessitates that we compare multiple interventions. Network meta-analysis (NMA) uses novel statistical methods that incorporate information from both direct and indirect treatment comparisons in a network of studies examining the effects of various competing treatments, estimating comparisons between many treatments in a single analysis. Despite its potential limitations, NMA applications in clinical epidemiology can be of great value in situations where there are several treatments that have been compared against a common comparator. Also, NMA can be relevant to a research or clinical question when many treatments must be considered or when there is a mix of both direct and indirect information in the body of evidence. Copyright © 2013 Elsevier España, S.L.U. All rights reserved.

Phentolamine mesylate to reverse oral soft-tissue local anesthesia: A systematic review and meta-analysis.

PubMed

Prados-Frutos, Juan Carlos; Rojo, Rosa; González-Serrano, José; González-Serrano, Carlos; Sammartino, Gilberto; Martínez-González, José María; Sánchez-Monescillo, Andrés

2015-10-01

Knowing that patients desire reduced duration of local anesthesia, the authors performed a meta-analysis to evaluate the efficacy of phentolamine mesylate (PM) in reducing anesthesia duration and the occurrence of adverse effects. The authors searched studies in 4 electronic databases up to December 18, 2014. For each study, the methodological quality was assessed according to the Cochrane Collaboration's tool for assessing risk of bias. Randomized controlled trials (RCTs) that used PM met the inclusion criteria. Six RCTs met the inclusion criteria and were used to carry out a meta-analysis of the effectiveness of PM and a qualitative analysis of its adverse effects. The use of PM was more effective in reversing the anesthetic effect on the lower lip and tongue than was applying a placebo. Adverse effects reported in the studies were not statistically significant, the most frequent being headache, pain during injection, and postprocedure pain. Based on limited evidence, PM is effective in reducing the persistence of anesthesia duration on the lower lip and tongue, with infrequent adverse effects of little clinical significance. Copyright © 2015 American Dental Association. Published by Elsevier Inc. All rights reserved.

Common and distinct neural correlates of personal and vicarious reward: A quantitative meta-analysis

PubMed Central

Morelli, Sylvia A.; Sacchet, Matthew D.; Zaki, Jamil

2015-01-01

Individuals experience reward not only when directly receiving positive outcomes (e.g., food or money), but also when observing others receive such outcomes. This latter phenomenon, known as vicarious reward, is a perennial topic of interest among psychologists and economists. More recently, neuroscientists have begun exploring the neuroanatomy underlying vicarious reward. Here we present a quantitative whole-brain meta-analysis of this emerging literature. We identified 25 functional neuroimaging studies that included contrasts between vicarious reward and a neutral control, and subjected these contrasts to an activation likelihood estimate (ALE) meta-analysis. This analysis revealed a consistent pattern of activation across studies, spanning structures typically associated with the computation of value (especially ventromedial prefrontal cortex) and mentalizing (including dorsomedial prefrontal cortex and superior temporal sulcus). We further quantitatively compared this activation pattern to activation foci from a previous meta-analysis of personal reward. Conjunction analyses yielded overlapping VMPFC activity in response to personal and vicarious reward. Contrast analyses identified preferential engagement of the nucleus accumbens in response to personal as compared to vicarious reward, and in mentalizing-related structures in response to vicarious as compared to personal reward. These data shed light on the common and unique components of the reward that individuals experience directly and through their social connections. PMID:25554428

How Acute Total Sleep Loss Affects the Attending Brain: A Meta-Analysis of Neuroimaging Studies

PubMed Central

Ma, Ning; Dinges, David F.; Basner, Mathias; Rao, Hengyi

2015-01-01

Study Objectives: Attention is a cognitive domain that can be severely affected by sleep deprivation. Previous neuroimaging studies have used different attention paradigms and reported both increased and reduced brain activation after sleep deprivation. However, due to large variability in sleep deprivation protocols, task paradigms, experimental designs, characteristics of subject populations, and imaging techniques, there is no consensus regarding the effects of sleep loss on the attending brain. The aim of this meta-analysis was to identify brain activations that are commonly altered by acute total sleep deprivation across different attention tasks. Design: Coordinate-based meta-analysis of neuroimaging studies of performance on attention tasks during experimental sleep deprivation. Methods: The current version of the activation likelihood estimation (ALE) approach was used for meta-analysis. The authors searched published articles and identified 11 sleep deprivation neuroimaging studies using different attention tasks with a total of 185 participants, equaling 81 foci for ALE analysis. Results: The meta-analysis revealed significantly reduced brain activation in multiple regions following sleep deprivation compared to rested wakefulness, including bilateral intraparietal sulcus, bilateral insula, right prefrontal cortex, medial frontal cortex, and right parahippocampal gyrus. Increased activation was found only in bilateral thalamus after sleep deprivation compared to rested wakefulness. Conclusion: Acute total sleep deprivation decreases brain activation in the fronto-parietal attention network (prefrontal cortex and intraparietal sulcus) and in the salience network (insula and medial frontal cortex). Increased thalamic activation after sleep deprivation may reflect a complex interaction between the de-arousing effects of sleep loss and the arousing effects of task performance on thalamic activity. Citation: Ma N, Dinges DF, Basner M, Rao H. How acute total

Statin use and the risk of Clostridium difficile infection: a systematic review with meta-analysis.

PubMed

Tariq, Raseen; Mukhija, Dhruvika; Gupta, Arjun; Singh, Siddharth; Pardi, Darrell S; Khanna, Sahil

2018-01-01

Statins have pleiotropic effects beyond cholesterol lowering by immune modulation. The association of statins with primary Clostridium difficile infection (CDI) is unclear as studies have reported conflicting findings. We performed a systematic review and meta-analysis to evaluate the association between statin use and CDI. We searched MEDLINE, Embase, and Web of Science from January 1978 to December 2016 for studies assessing the association between statin use and CDI. The Newcastle-Ottawa Scale was used to assess the methodologic quality of included studies. Weighted summary estimates were calculated using generalized inverse variance with random-effects model. Eight studies (6 case-control and 2 cohort) were included in the meta-analysis, which comprised 156,722 patients exposed to statins and 356,185 controls, with 34,849 total cases of CDI available in 7 studies. The rate of CDI in patients with statin use was 4.3%, compared with 7.8% in patients without statin use. An overall meta-analysis of 8 studies using the random-effects model demonstrated that statins may be associated with a decreased risk of CDI (maximally adjusted odds ratio [OR], 0.80; 95% CI, 0.66-0.97; P =0.02). There was significant heterogeneity among the studies, with an I 2 of 79%. No publication bias was seen. Meta-analysis of studies that adjusted for confounders revealed no protective effect of statins (adjusted OR, 0.84; 95% CI, 0.70-1.01; P =0.06, I 2 =75%). However, a meta-analysis of only full-text studies using the random-effects model demonstrated a decreased risk of CDI with the use of statins (OR 0.77; 95% CI, 0.61-0.99; P =0.04, I 2 =85%). Meta-analyses of existing studies suggest that patients prescribed a statin may be at decreased risk for CDI. The results must be interpreted with caution given the significant heterogeneity and lack of benefit on analysis of studies that adjusted for confounders.

Effects of Expository Text Structure Interventions on Comprehension: A Meta-Analysis

ERIC Educational Resources Information Center

Pyle, Nicole; Vasquez, Ariana C.; Lignugaris/Kraft, Benjamin; Gillam, Sandra L.; Reutzel, D. Ray; Olszewski, Abbie; Segura, Hugo; Hartzheim, Daphne; Laing, Woodrow; Pyle, Daniel

2017-01-01

This meta-analysis synthesizes results from expository text structure interventions designed to increase comprehension for students in kindergarten to grade 12 published between 1970 and 2013. Twenty-one studies were identified, 19 of which met criteria for a meta-analysis, including 48 studywise effect sizes that were meta-analyzed to determine…

Social support, social integration, and inflammatory cytokines: A meta-analysis.

PubMed

Uchino, Bert N; Trettevik, Ryan; Kent de Grey, Robert G; Cronan, Sierra; Hogan, Jasara; Baucom, Brian R W

2018-05-01

Social support and social integration have been linked to lower rates of morbidity and mortality. However, the biological mechanisms responsible for such links need greater attention to advance theory and unique intervention opportunities. The main aim of this article was to conduct a meta-analytic review of the association between social support-social integration and inflammatory cytokines (e.g., interleukin-6, C-reactive protein) and test several proposed moderators from prior qualitative reviews. A literature search was conducted using the ancestry approach and with databases PsycINFO, Medline, and EMBASE by crossing the exact keywords social support or social integration with inflammation . The review identified 41 studies with a total of 73,037 participants. The omnibus meta-analysis showed that social support-social integration were significantly related to lower levels of inflammation (Zr = -.073). These results were not moderated by the operationalization of social relationships or the type of population, cytokine, and design. These data suggest that inflammation is at least one important biological mechanism linking social support and social integration to the development and course of disease. Future work should continue to build on this review and address next-generation questions regarding antecedent processes, mechanisms, and other potential moderators. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Effectiveness of Valerian on insomnia: a meta-analysis of randomized placebo-controlled trials.

PubMed

Fernández-San-Martín, Maria Isabel; Masa-Font, Roser; Palacios-Soler, Laura; Sancho-Gómez, Pilar; Calbó-Caldentey, Cristina; Flores-Mateo, Gemma

2010-06-01

Insomnia is an often seen primary health care problem. Valerian might be an alternative treatment with fewer secondary effects. The aim of this study is to evaluate its effectiveness on insomnia through a meta-analysis of published literature. Search for randomized clinical trials (RCTs) of Valerian preparations compared with a placebo on Medline, the Cochrane Library, Embase and Biosis. sleep-quality improvement (SQ, yes/no), sleep-quality improvement quantified through visual analogical scales (SQS) and the latency time (LT) in minutes until getting to sleep. Three meta-analyses were carried out using inverse-variance weighted random effects models. Heterogeneity was determined with the Q-statistic and was explored through a sub-groups analysis. Publication bias was evaluated using the funnel plot. Eighteen RCTs were selected; eight had a score of 5 on Jadad's scale. The mean differences in LT between the Valerian and placebo treatment groups was 0.70 min (95% CI, -3.44 to 4.83); the standardized mean differences between the groups measured with SQS was -0.02 (95% CI, -0.35 to 0.31); treatment with Valerian showed a relative risk of SQ of 1.37 (95% CI, 1.05-1.78) compared with the placebo group. There was heterogeneity in the three meta-analyses, but it diminished in the sub groups analysis. No publication bias was detected. The qualitative dichotomous results suggest that valerian would be effective for a subjective improvement of insomnia, although its effectiveness has not been demonstrated with quantitative or objective measurements. We recommend future investigations oriented toward improving insomnia with other more promising treatments. Copyright 2010 Elsevier B.V. All rights reserved.

Barriers and facilitators associated with return to work after stroke: a qualitative meta-synthesis.

PubMed

Brannigan, Colm; Galvin, Rose; Walsh, Mary E; Loughnane, Cliona; Morrissey, Emma-Jane; Macey, Chris; Delargy, Mark; Horgan, N Frances

2017-02-01

To enhance the employment outcomes of individuals who experience a stroke, it is essential to understand the factors that determine successful return to work. The aim of this systematic review was to examine barriers to and facilitators of return to work after stroke from the perspective of people with stroke through the process of a qualitative meta-synthesis. A systematic literature search was conducted. Studies that employed qualitative methods to explore the experiences of individuals with stroke around return to work after stroke were included. The methodological quality of the studies was assessed by two independent reviewers. Overarching themes, concepts and interpretations were extracted from each individual study, compared and meta-synthesized. Fifteen studies were included and the overall methodological quality of the studies was good. Four broad themes emerged as factors associated with return to work after stroke. These included (i) the nature of the effects of stroke, (ii) the preparatory environment, (iii) personal coping strategies and internal challenges and (iv) the meaning of work. Return to work after stroke is a complex process which can be facilitated or impeded by organizational, social or personal factors, as well as accessibility to appropriate services. Implications for Rehabilitation Following a period of dedicated inpatient rehabilitation, there is a need to integrate community-support services to optimize return to work among stroke survivors. A dedicated community stroke support liaison officer may help to facilitate the transition between the hospital and the community and workplace environment. Education provided by healthcare professionals is necessary in the community and the workplace to ensure that family, friends and employers are aware of the impairments, activity limitations and participation restrictions of the stroke survivor.

A qualitative systematic review of patients' experience of osteoporosis using meta-ethnography.

PubMed

Barker, K L; Toye, F; Lowe, C J Minns

2016-12-01

We aimed to systematically review qualitative studies exploring the experience of living with osteoporosis to develop new conceptual understanding. We identified themes about the invisibility/visibility of osteoporosis, the experience of uncertainty of living with osteoporosis (OP) and living with an ageing body and the place of gender. The aim of this review was to systematically review the body of qualitative studies exploring the experience of living with either osteoporosis or osteopenia and to use meta-ethnography to develop new conceptual understanding. We systematically reviewed and integrated the findings of qualitative research from four bibliographic databases (Medline, Embase, Cinahl, Psychinfo) to September 2015 in order to increase our conceptual understanding of the lived experience of osteoporosis and osteopenia. Articles were appraised for quality; each was independently read by two researchers to identify concepts which were compared and developed into a conceptual model. Our findings demonstrate that coming to terms with a diagnosis of osteoporosis is linked to its relative visibility or invisibility. For some, OP has not become manifest and self-identity is intact (biographical integrity). For others, OP is profoundly manifest and self-identity is no long intact (biographical fracture). We also demonstrate that overwhelming uncertainty pervades the experience of OP. Our final theme demonstrates how the experience of OP is set within a cultural context with certain views about ageing and gender. Our synthesis has highlighted the wealth of qualitative data about osteoporosis and osteopenia. Despite the increasing body of literature on the subject, there remains a need to adjust our interactions with patients. This will allow clinicians to understand how patients can be helped to receive and understand their diagnosis and move forward in partnership with healthcare providers to promote optimal management of the disease.

Interleukin-10 Promoter Gene Polymorphisms and Susceptibility to Asthma: A Meta-Analysis

PubMed Central

Hyun, Myung-Han; Lee, Chung-Ho; Kang, Min-Hyung; Park, Bong-Kyung; Lee, Young Ho

2013-01-01

Objective The aim of this study was to explore whether the interleukin (IL)-10 polymorphisms and their haplotypes contribute to asthma susceptibility. Methods MEDLINE, EMBASE and the COCHRANE library databases were utilized to identify available articles. A meta-analysis was conducted on IL-10 -1082 G/A, -819 C/T, -592 C/A polymorphisms, and their haplotypes and asthma. Results Eleven studies involving 2,215 asthma patients and 2,170 controls were considered in the meta-analysis. The meta-analysis revealed no association between asthma and the IL-10 -1082 G allele [Odds ratio (OR) = 0.87, 95% Confidence interval (CI) = 0.68–1.12, p = 0.28]. However, meta-analysis of the five studies in Hardy-Weinburg equilibrium produced the relationship between the IL-10 -1082 G allele and asthma (OR = 0.71, 95% CI = 0.60–0.83, p<0.0001). Stratification by ethnicity indicated an association between the IL-10 -1082 G allele and asthma in East Asians (OR = 0.74, 95% CI = 0.57–0.96, p = 0.02), but not in West Asians. Furthermore, stratification by age indicated an association between the IL-10 -1082 G allele and asthma in adults and mixed groups (OR = 0.77, 95% CI = 0.62–0.96, p = 0.02; OR = 0.67, 95% CI = 0.49–0.92, p = 0.01). No association was found between asthma and IL-10 -819 C/T and IL-10 -592 C/A polymorphisms and their haplotypes. Conclusion The IL-10 -1082 G/A polymorphism confers susceptibility to asthma in East Asians and in adults. However, the IL-10 -819 C/T, -592 C/A polymorphisms and their haplotypes are not associated with asthma. PMID:23335974

Sleep, Cognitive impairment, and Alzheimer's disease: A Systematic Review and Meta-Analysis.

PubMed

Bubu, Omonigho M; Brannick, Michael; Mortimer, James; Umasabor-Bubu, Ogie; Sebastião, Yuri V; Wen, Yi; Schwartz, Skai; Borenstein, Amy R; Wu, Yougui; Morgan, David; Anderson, William M

2017-01-01

Mounting evidence implicates disturbed sleep or lack of sleep as one of the risk factors for Alzheimer's disease (AD), but the extent of the risk is uncertain. We conducted a broad systematic review and meta-analysis to quantify the effect of sleep problems/disorders on cognitive impairment and AD. Original published literature assessing any association of sleep problems or disorders with cognitive impairment or AD was identified by searching PubMed, Embase, Web of Science, and the Cochrane library. Effect estimates of individual studies were pooled and relative risks (RR) and 95% confidence intervals (CI) were calculated using random effects models. We also estimated the population attributable risk. Twenty-seven observational studies (n = 69216 participants) that provided 52 RR estimates were included in the meta-analysis. Individuals with sleep problems had a 1.55 (95% CI: 1.25-1.93), 1.65 (95% CI: 1.45-1.86), and 3.78 (95% CI: 2.27-6.30) times higher risk of AD, cognitive impairment, and preclinical AD than individuals without sleep problems, respectively. The overall meta-analysis revealed that individuals with sleep problems had a 1.68 (95% CI: 1.51-1.87) times higher risk for the combined outcome of cognitive impairment and/or AD. Approximately 15% of AD in the population may be attributed to sleep problems. This meta-analysis confirmed the association between sleep and cognitive impairment or AD and, for the first time, consolidated the evidence to provide an "average" magnitude of effect. As sleep problems are of a growing concern in the population, these findings are of interest for potential prevention of AD. © Sleep Research Society 2016. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Plasma ET-1 Concentrations are Elevated in Patients with Hypertension - Meta-Analysis of Clinical Studies.

PubMed

Xu, Mei; Lu, Yong-Ping; Hasan, Ahmed Abdallah; Hocher, Berthold

2017-01-01

A recent study revealed that global overexpression of ET-1 causes a slight reduction in systemic blood pressure. Moreover, heterozygous ET-1 knockout mice are hypertensive. The role of ET-1 in human hypertension was so far not addressed by a strict meta-analysis of published human clinical studies. We included studies published between January 1, 1990 and February 28, 2017. We included case control studies analyzing untreated essential hypertension or hypertensive patients where antihypertensive medication was discontinued for at least two weeks. Based on the principle of Cochrane systematic reviews, case control studies (CCSs) in PubMed (Medline) and Google Scholar designed to identify the role of endothelin-1 (ET-1) in the pathophysiological of hypertension were screened. Review Manager Version 5.0 (Rev-Man 5.0) was applied for statistical analysis. Mean difference and 95% confidence interval (CI) were shown in inverse variance (IV) fixed-effects model or IV random-effects models. Eleven studies fulfilling our in- and exclusion criteria were eligible for this meta-analysis. These studies included 450 hypertensive patients and 328 controls. Our meta-analysis revealed that ET-1 plasma concentrations were higher in hypertensive patients as compared to the control patients [mean difference between groups 1.57 pg/mL, 95%CI [0.47∼2.68, P = 0.005]. These finding were driven by patients having systolic blood pressure higher than 160 mmHg and diastolic blood pressure higher than 100 mmHg. This meta-analysis showed that hypertensive patients do have elevated plasma ET-1 concentrations. This finding is driven by those patients with high systolic/diastolic blood pressure. Given that the ET-1 gene did not appear in any of the whole genome association studies searching for hypertension associated gene loci, it is very likely that the elevated plasma ET-1 concentrations in hypertensive patients are secondary to hypertension and may reflect endothelial cell damage. © 2017 The

How do the features of mindfulness-based cognitive therapy contribute to positive therapeutic change? A meta-synthesis of qualitative studies.

PubMed

Cairns, Victoria; Murray, Craig

2015-05-01

The exploration of Mindfulness-based Cognitive Therapy through qualitative investigation is a growing area of interest within current literature, providing valuable understanding of the process of change experienced by those engaging in this therapeutic approach. This meta-synthesis aims to gain a deeper understanding of how the features of Mindfulness-based Cognitive Therapy contribute to positive therapeutic change. Noblit and Hare's (1988) 7-step meta-ethnography method was conducted in order to synthesize the findings of seven qualitative studies. The process of reciprocal translation identified the following five major themes: i) Taking control through understanding, awareness and acceptance; ii) The impact of the group; (iii) Taking skills into everyday life; (iv) Feelings towards the self; (v) The role of expectations. The synthesis of translation identified the higher order concept of "The Mindfulness-based Cognitive Therapy Journey to Change", which depicts the complex interaction between the five themes in relation to how they contribute to positive therapeutic change. The findings are discussed in relation to previous research, theory and their implications for clinical practice.

Acellular dermal matrix for mucogingival surgery: a meta-analysis.

PubMed

Gapski, Ricardo; Parks, Christopher Allen; Wang, Hom-Lay

2005-11-01

Many clinical studies revealed the effectiveness of acellular dermal matrix (ADM) in the treatment of mucogingival defects. The purpose of this meta-analysis was to compare the efficacy of ADM-based root coverage (RC) and ADM-based increase in keratinized tissues to other commonly used mucogingival surgeries. Meta-analysis was limited to randomized clinical trials (RCT). Articles from January 1, 1990 to October 2004 related to ADM were searched utilizing the MEDLINE database from the National Library of Medicine, the Cochrane Oral Health Group Specialized Trials Registry, and through hand searches of reviews and recent journals. Relevant studies were identified, ranked independently, and mean data from each were weighted accordingly. Selected outcomes were analyzed using a meta-analysis software program. The significant estimates of the treatment effects from different trials were assessed by means of Cochrane's test of heterogeneity. 1) Few RCT studies were found to compile the data. In summary, selection identified eight RCT that met the inclusion criteria. There were four studies comparing ADM versus a connective tissue graft for root coverage procedures, two studies comparing ADM versus coronally advanced flap (CAF) for root coverage procedures, and two studies comparing ADM to free gingival graft in augmentation of keratinized tissue. 2) There were no statistically significant differences between groups for any of the outcomes measured (recession coverage, keratinized tissue formation, probing depths, and clinical attachment levels). 3) The majority of the analyses demonstrated moderate to high levels of heterogeneity. 4) Considering the heterogeneity values found among the studies, certain trends could be found: a) three out of four studies favored the ADM-RC group for recession coverage; b) a connective tissue graft tended to increase keratinized tissue compared to ADM (0.52-mm difference; P = 0.11); c) there were trends of increased clinical attachment

Obesity, stigma, and responsibility in health care: A synthesis of qualitative studies

PubMed Central

Ulriksen, Kjersti

2011-01-01

Objective To synthesize research findings on experiences and attitudes about obesity and stigma in health care. Methods We compiled qualitative studies and applied Noblitt & Hare's meta ethnography to identify, translate, and summarize across studies. Thirteen qualitative studies on experiences and attitudes about obesity and stigma in health care settings were identified and included. Results The study reveals how stigmatizing attitudes are enacted by health care providers and perceived by patients with obesity. Second-order analysis demonstrated that apparently appropriate advice can be perceived as patronizing by patients with obesity. Furthermore, health care providers indicate that abnormal bodies cannot be incorporated in the medical systems—exclusion of patients with obesity consequently happens. Finally, customary standards for interpersonal respect are legitimately surpassed, and patients with obesity experience contempt as if deserved. Third-order analysis revealed conflicting views between providers and patients with obesity on responsibility, whereas internalized stigma made patients vulnerable for accepting a negative attribution. A theoretical elaboration relates the issues of stigma with those of responsibility. Conclusion Contradictory views on patients’ responsibility, efforts, knowledge, and motivation merge to internalization of stigma, thereby obstructing healthy coping and collaboration and creating negative contexts for empowerment, self-efficacy, and weight management. Professionals need to develop their awareness for potentially stigmatizing attitudes towards vulnerable patient populations. PMID:22121389

Meta-analysis identifies a MECOM gene as a novel predisposing factor of osteoporotic fracture

PubMed Central

Hwang, Joo-Yeon; Lee, Seung Hun; Go, Min Jin; Kim, Beom-Jun; Kou, Ikuyo; Ikegawa, Shiro; Guo, Yan; Deng, Hong-Wen; Raychaudhuri, Soumya; Kim, Young Jin; Oh, Ji Hee; Kim, Youngdoe; Moon, Sanghoon; Kim, Dong-Joon; Koo, Heejo; Cha, My-Jung; Lee, Min Hye; Yun, Ji Young; Yoo, Hye-Sook; Kang, Young-Ah; Cho, Eun-Hee; Kim, Sang-Wook; Oh, Ki Won; Kang, Moo II; Son, Ho Young; Kim, Shin-Yoon; Kim, Ghi Su; Han, Bok-Ghee; Cho, Yoon Shin; Cho, Myeong-Chan; Lee, Jong-Young; Koh, Jung-Min

2014-01-01

Background Osteoporotic fracture (OF) as a clinical endpoint is a major complication of osteoporosis. To screen for OF susceptibility genes, we performed a genome-wide association study and carried out de novo replication analysis of an East Asian population. Methods Association was tested using a logistic regression analysis. A meta-analysis was performed on the combined results using effect size and standard errors estimated for each study. Results In a combined meta-analysis of a discovery cohort (288 cases and 1139 controls), three hospital based sets in replication stage I (462 cases and 1745 controls), and an independent ethnic group in replication stage II (369 cases and 560 for controls), we identified a new locus associated with OF (rs784288 in the MECOM gene) that showed genome-wide significance (p=3.59×10−8; OR 1.39). RNA interference revealed that a MECOM knockdown suppresses osteoclastogenesis. Conclusions Our findings provide new insights into the genetic architecture underlying OF in East Asians. PMID:23349225

Disclosure of sensitive behaviors across self-administered survey modes: a meta-analysis.

PubMed

Gnambs, Timo; Kaspar, Kai

2015-12-01

In surveys, individuals tend to misreport behaviors that are in contrast to prevalent social norms or regulations. Several design features of the survey procedure have been suggested to counteract this problem; particularly, computerized surveys are supposed to elicit more truthful responding. This assumption was tested in a meta-analysis of survey experiments reporting 460 effect sizes (total N =125,672). Self-reported prevalence rates of several sensitive behaviors for which motivated misreporting has been frequently observed were compared across self-administered paper-and-pencil versus computerized surveys. The results revealed that computerized surveys led to significantly more reporting of socially undesirable behaviors than comparable surveys administered on paper. This effect was strongest for highly sensitive behaviors and surveys administered individually to respondents. Moderator analyses did not identify interviewer effects or benefits of audio-enhanced computer surveys. The meta-analysis highlighted the advantages of computerized survey modes for the assessment of sensitive topics.

Offspring of Parents with Chronic Pain: A Systematic Review and Meta-Analysis of Pain, Health, Psychological, and Family Outcomes

PubMed Central

Higgins, Kristen S.; Birnie, Kathryn A.; Chambers, Christine T.; Wilson, Anna C.; Caes, Line; Clark, Alexander J.; Lynch, Mary; Stinson, Jennifer; Campbell-Yeo, Marsha

2015-01-01

Offspring of parents with chronic pain may be at risk for poorer outcomes than offspring of healthy parents. The objective of this research was to provide a comprehensive mixed-methods, systematic synthesis of all available research on outcomes in offspring of parents with chronic pain. A systematic search was conducted for published articles in English examining pain, health, psychological, or family outcomes in offspring of parents with chronic pain. Fifty-nine eligible articles were identified (31 population-based, 25 clinical, 3 qualitative), including offspring from birth to adulthood and parents with varying chronic pain diagnoses (e.g., mixed pain samples, arthritis). Meta-analysis was used to synthesize the results from population-based and clinical studies, while meta-ethnography was used to synthesize the results of qualitative studies. Increased pain complaints were found in offspring of mothers and of fathers with chronic pain, and when both parents had chronic pain. Newborns of mothers with chronic pain were more likely to have adverse birth outcomes, including low birthweight, preterm delivery, caesarean section, intensive care admission, and mortality. Offspring of parents with chronic pain had greater externalizing and internalizing problems and poorer social competence and family outcomes. No significant differences were found on teacher-reported externalizing problems. The meta-ethnography identified six key concepts (developing independence, developing compassion, learning about health and coping, missing out, emotional health, and struggles communicating with parents). Across study designs, offspring of parents with chronic pain had poorer outcomes than other offspring, although the meta-ethnography noted some constructive impact of having a parent with chronic pain. PMID:26172553

The prevalence of compulsive buying: a meta-analysis.

PubMed

Maraz, Aniko; Griffiths, Mark D; Demetrovics, Zsolt

2016-03-01

To estimate the pooled prevalence of compulsive buying behaviour (CBB) in different populations and to determine the effect of age, gender, location and screening instrument on the reported heterogeneity in estimates of CBB and whether publication bias could be identified. Three databases were searched (Medline, PsychInfo, Web of Science) using the terms 'compulsive buying', 'pathological buying' and 'compulsive shopping' to estimate the pooled prevalence of CBB in different populations. Forty studies reporting 49 prevalence estimates from 16 countries were located (n = 32,000). To conduct the meta-analysis, data from non-clinical studies regarding mean age and gender proportion, geographical study location and screening instrument used to assess CBB were extracted by multiple independent observers and evaluated using a random-effects model. Four a priori subgroups were analysed using pooled estimation (Cohen's Q) and covariate testing (moderator and meta-regression analysis). The CBB pooled prevalence of adult representative studies was 4.9% (3.4-6.9%, eight estimates, 10,102 participants), although estimates were higher among university students: 8.3% (5.9-11.5%, 19 estimates, 14,947 participants) in adult non-representative samples: 12.3% (7.6-19.1%, 11 estimates, 3929 participants) and in shopping-specific samples: 16.2% (8.8-27.8%, 11 estimates, 4686 participants). Being young and female were associated with increased tendency, but not location (United States versus non-United States). Meta-regression revealed large heterogeneity within subgroups, due mainly to diverse measures and time-frames (current versus life-time) used to assess CBB. A pooled estimate of compulsive buying behaviour in the populations studied is approximately 5%, but there is large variation between samples accounted for largely by use of different time-frames and measures. © 2016 Society for the Study of Addiction.

Culturally competent health care from the immigrant lens: a qualitative interpretive meta-synthesis (QIMS).

PubMed

Maleku, Arati; Aguirre, Regina T P

2014-01-01

Immigrant groups comprise a large segment of ethnic minorities in the United States. Although the literature is rich with strategies to deliver culturally and linguistically appropriate services to eliminate health inequities, studies addressing cultural competence from the immigrant's perspective are limited. Further research is needed to build knowledge of the predictors and needs of this population, and to influence health care policy and practice. Using qualitative interpretive meta-synthesis, this study describes the lived experience of immigrants accessing health care to understand the essence of cultural competence in health care through their lens. Findings provide insight on expanding the definition of culturally competent health care beyond language, behaviors, attitudes, and policies.

The coordinate-based meta-analysis of neuroimaging data.

PubMed

Samartsidis, Pantelis; Montagna, Silvia; Nichols, Thomas E; Johnson, Timothy D

2017-01-01

Neuroimaging meta-analysis is an area of growing interest in statistics. The special characteristics of neuroimaging data render classical meta-analysis methods inapplicable and therefore new methods have been developed. We review existing methodologies, explaining the benefits and drawbacks of each. A demonstration on a real dataset of emotion studies is included. We discuss some still-open problems in the field to highlight the need for future research.

The coordinate-based meta-analysis of neuroimaging data

PubMed Central

Samartsidis, Pantelis; Montagna, Silvia; Nichols, Thomas E.; Johnson, Timothy D.

2017-01-01

Neuroimaging meta-analysis is an area of growing interest in statistics. The special characteristics of neuroimaging data render classical meta-analysis methods inapplicable and therefore new methods have been developed. We review existing methodologies, explaining the benefits and drawbacks of each. A demonstration on a real dataset of emotion studies is included. We discuss some still-open problems in the field to highlight the need for future research. PMID:29545671

Classroom Communication and Instructional Processes: Advances through Meta-Analysis

ERIC Educational Resources Information Center

Gayle, Barbara Mae, Ed.; Preiss, Raymond W., Ed.; Burrell, Nancy, Ed.; Allen, Mike, Ed.

2006-01-01

This volume offers a systematic review of the literature on communication education and instruction. Making meta-analysis findings accessible and relevant, the editors of this volume approach the topic from the perspective that meta-analysis serves as a useful tool for summarizing experiments and for determining how and why specific teaching and…

A regulation probability model-based meta-analysis of multiple transcriptomics data sets for cancer biomarker identification.

PubMed

Xie, Xin-Ping; Xie, Yu-Feng; Wang, Hong-Qiang

2017-08-23

Large-scale accumulation of omics data poses a pressing challenge of integrative analysis of multiple data sets in bioinformatics. An open question of such integrative analysis is how to pinpoint consistent but subtle gene activity patterns across studies. Study heterogeneity needs to be addressed carefully for this goal. This paper proposes a regulation probability model-based meta-analysis, jGRP, for identifying differentially expressed genes (DEGs). The method integrates multiple transcriptomics data sets in a gene regulatory space instead of in a gene expression space, which makes it easy to capture and manage data heterogeneity across studies from different laboratories or platforms. Specifically, we transform gene expression profiles into a united gene regulation profile across studies by mathematically defining two gene regulation events between two conditions and estimating their occurring probabilities in a sample. Finally, a novel differential expression statistic is established based on the gene regulation profiles, realizing accurate and flexible identification of DEGs in gene regulation space. We evaluated the proposed method on simulation data and real-world cancer datasets and showed the effectiveness and efficiency of jGRP in identifying DEGs identification in the context of meta-analysis. Data heterogeneity largely influences the performance of meta-analysis of DEGs identification. Existing different meta-analysis methods were revealed to exhibit very different degrees of sensitivity to study heterogeneity. The proposed method, jGRP, can be a standalone tool due to its united framework and controllable way to deal with study heterogeneity.

BMI levels with MS Bone mineral density levels in adults with multiple sclerosis: a meta-analysis.

PubMed

Huang, Zhongming; Qi, Yiying; Du, Shaohua; Chen, Guangnan; Yan, Weiqi

2015-01-01

Multiple sclerosis (MS) and osteoporosis (OP) affect a substantial proportion of the population. Accumulating evidence suggests that MS patients are at high risk for OP. We performed a meta-analysis to identify risk factors for lowered bone mineral density (BMD) in MS patients. We searched for articles within the Medline, Embase and Cochrane Library databases, published up to March 2014, pertaining to associations between MS and BMD. A total of 11 studies was included in the meta-analysis. The analysis indicated that MS patients have reduced lumbar spine, femur neck, and hip BMD compared with healthy controls (lumbar spine, standardized mean difference (SMD) = -0.76, 95% CI: -1.07, -0.45; femur neck, SMD = -0.56, 95% CI: -0.84, -0.29; and hip, SMD = -0.62, 95% CI: -0.96, -0.29). Further subgroup analysis revealed that a disease duration of >7 years, total steroid dose during the disease of >15 g, and an Expanded Disability Status Scale (EDSS) score of > 3, increased the risk of reduced BMD in the lumbar spine and femoral neck, but not in the hip. Meta-regression analysis did not explain the heterogeneity in the clinical characteristics or outcome definitions. Our meta-analysis suggests that MS patients have reduced overall BMD compared with healthy controls. Furthermore, disease duration (>7 years), total steroid dose (>15 g), and EDSS score (>3) are risk factors for reduced BMD in MS patients.

Insomnia and the risk of depression: a meta-analysis of prospective cohort studies.

PubMed

Li, Liqing; Wu, Chunmei; Gan, Yong; Qu, Xianguo; Lu, Zuxun

2016-11-05

Observational studies suggest that insomnia might be associated with an increased risk of depression with inconsistent results. This study aimed at conducting a meta-analysis of prospective cohort studies to evaluate the association between insomnia and the risk of depression. Relevant cohort studies were comprehensively searched from the PubMed, Embase, Web of Science, and China National Knowledge Infrastructure databases (up to October 2014) and from the reference lists of retrieved articles. A random-effects model was used to calculate the pooled risk estimates and 95 % confidence intervals (CIs). The I 2 statistic was used to assess the heterogeneity and potential sources of heterogeneity were assessed with meta-regression. The potential publication bias was explored by using funnel plots, Egger's test, and Duval and Tweedie trim-and-fill methods. Thirty-four cohort studies involving 172,077 participants were included in this meta-analysis with an average follow-up period of 60.4 months (ranging from 3.5 to 408). Statistical analysis suggested a positive relationship between insomnia and depression, the pooled RR was 2.27 (95 % CI: 1.89-2.71), and a high heterogeneity was observed (I 2  = 92.6 %, P < 0.001). Visual inspection of the funnel plot revealed some asymmetry. The Egger's test identified evidence of substantial publication bias (P <0.05), but correction for this bias using trim-and-fill method did not alter the combined risk estimates. This meta-analysis indicates that insomnia is significantly associated with an increased risk of depression, which has implications for the prevention of depression in non-depressed individuals with insomnia symptoms.

Cooperative macromolecular device revealed by meta-analysis of static and time-resolved structures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ren, Zhong; Šrajer, Vukica; Knapp, James E.

2013-04-08

Here we present a meta-analysis of a large collection of static structures of a protein in the Protein Data Bank in order to extract the progression of structural events during protein function. We apply this strategy to the homodimeric hemoglobin HbI from Scapharca inaequivalvis. We derive a simple dynamic model describing how binding of the first ligand in one of the two chemically identical subunits facilitates a second binding event in the other partner subunit. The results of our ultrafast time-resolved crystallographic studies support this model. We demonstrate that HbI functions like a homodimeric mechanical device, such as pliers ormore » scissors. Ligand-induced motion originating in one subunit is transmitted to the other via conserved pivot points, where the E and F' helices from two partner subunits are 'bolted' together to form a stable dimer interface permitting slight relative rotation but preventing sliding.« less

Essential ingredients of engagement when working alongside people after their first episode of psychosis: A qualitative meta-synthesis.

PubMed

Tindall, Rachel M; Simmons, Magenta B; Allott, Kelly; Hamilton, Bridget E

2018-04-06

Early intervention services (EISs) for first-episode psychosis (FEP) have been established internationally, however, service disengagement is a recurrent concern resulting in unplanned treatment cessation. The implications of this are far-reaching due to the financial and personal costs associated with untreated symptoms. The aim of this meta-synthesis was to collect, interpret and synthesize qualitative research about how engagement is experienced within EISs for FEP. A systematic search was conducted in PsycINFO, Ovid MEDLINE and Ovid Emcare from date of conception to November 2016. Following initial screening, 91 abstracts and 13 full texts were reviewed for eligibility. Nine studies were then critically appraised using the CASP tool for qualitative studies, data were systematically extracted and results were synthesized using constant comparison and reciprocal translational analysis. Nine qualitative studies explored engagement with EISs, from the perspectives of service users and their caregivers. No studies were found from the perspectives of clinicians or services. All 9 studies employed an inductive methodology, within an interpretivist epistemology. Five main themes were identified: experiences of finding help; factors promoting engagement; the therapeutic relationship; the role of caregivers in supporting engagement; and factors impacting ongoing engagement. There is a critical need to stimulate discussion around this multifaceted phenomenon, including a continued focus on the roles of key stakeholders and clinical models that may further facilitate collaboration in treatment plans and recovery. © 2018 John Wiley & Sons Australia, Ltd.

Fall-Risk-Increasing Drugs: A Systematic Review and Meta-Analysis: II. Psychotropics.

PubMed

Seppala, Lotta J; Wermelink, Anne M A T; de Vries, Max; Ploegmakers, Kimberley J; van de Glind, Esther M M; Daams, Joost G; van der Velde, Nathalie

2018-04-01

Falls are a major public health problem in older adults. Earlier studies showed that psychotropic medication use increases the risk of falls. The aim of this study is to update the current knowledge by providing a comprehensive systematic review and meta-analysis on psychotropic medication use and falls in older adults. This study is a systematic review and meta-analysis. A search was conducted in Medline, PsycINFO, and Embase. Key search concepts were "falls," "aged," "medication," and "causality." Studies were included that investigated psychotropics (antipsychotics, antidepressants, anxiolytics, sedatives, and hypnotics) as risk factors for falls in participants ≥60 years of age or participants with a mean age of ≥70 years. Meta-analyses were performed using generic inverse variance method pooling unadjusted and adjusted odds ratio (OR) estimates separately. In total, 248 studies met the inclusion criteria for qualitative synthesis. Meta-analyses using adjusted data showed the following pooled ORs: antipsychotics 1.54 [95% confidence interval (CI) 1.28-1.85], antidepressants 1.57 (95% Cl 1.43-1.74), tricyclic antidepressants 1.41 (95% CI 1.07-1.86), selective serotonin reuptake inhibitors 2.02 (95% CI 1.85-2.20), benzodiazepines 1.42 (95%, CI 1.22-1.65), long-acting benzodiazepines 1.81 (95%, CI 1.05-3.16), and short-acting benzodiazepines 1.27 (95%, CI 1.04-1.56) Most of the meta-analyses resulted in substantial heterogeneity that did not disappear after stratification for population and healthcare setting. Antipsychotics, antidepressants, and benzodiazepines are consistently associated with a higher risk of falls. It is unclear whether specific subgroups such as short-acting benzodiazepines and selective serotonin reuptake inhibitors are safer in terms of fall risk. Prescription bias could not be accounted for. Future studies need to address pharmacologic subgroups as fall risk may differ depending on specific medication properties. Precise and uniform

Effect of Whey Supplementation on Circulating C-Reactive Protein: A Meta-Analysis of Randomized Controlled Trials

PubMed Central

Zhou, Ling-Mei; Xu, Jia-Ying; Rao, Chun-Ping; Han, Shufen; Wan, Zhongxiao; Qin, Li-Qiang

2015-01-01

Whey supplementation is beneficial for human health, possibly by reducing the circulating C-reactive protein (CRP) level, a sensitive marker of inflammation. Thus, a meta-analysis of randomized controlled trials was conducted to evaluate their relationship. A systematic literature search was conducted in July, 2014, to identify eligible studies. Either a fixed-effects model or a random-effects model was used to calculate pooled effects. The meta-analysis results of nine trials showed a slight, but no significant, reduction of 0.42 mg/L (95% CI −0.96, 0.13) in CRP level with the supplementation of whey protein and its derivates. Relatively high heterogeneity across studies was observed. Subgroup analyses showed that whey significantly lowered CRP by 0.72 mg/L (95% CI −0.97, −0.47) among trials with a daily whey dose ≥20 g/day and by 0.67 mg/L (95% CI −1.21, −0.14) among trials with baseline CRP ≥3 mg/L. Meta-regression analysis revealed that the baseline CRP level was a potential effect modifier of whey supplementation in reducing CRP. In conclusion, our meta-analysis did not find sufficient evidence that whey and its derivates elicited a beneficial effect in reducing circulating CRP. However, they may significantly reduce CRP among participants with highly supplemental doses or increased baseline CRP levels. PMID:25671415

Increased risk of mortality in systemic sclerosis-associated digital ulcers: a systematic review and meta-analysis.

PubMed

Meunier, Pauline; Dequidt, Laure; Barnetche, Thomas; Lazaro, Estibaliz; Duffau, Pierre; Richez, Christophe; Couzi, Lionel; Truchetet, Marie-Elise; Seneschal, Julien

2018-06-10

Survival can be threatened in certain forms of systemic sclerosis (SSc) so clear prognostic factors are needed. The aim of this meta-analysis was to assess the association between the presence of digital ulcers (DUs) and mortality in SSc. We performed a systematic review and meta-analysis in the Pubmed and Scopus databases from the earliest records to May 2017. Two research strategies were performed: « systemic sclerosis » and « digital ulcers » (strategy A); « systemic sclerosis » and « mortality » (strategy B). The primary outcome was the mortality associated with the presence of DUs in patients with SSc. The literature search identified 1473 citations. Fifty-nine studies were examined for full text. Ten articles were included for the meta-analysis. SSc patients with DUs had an increased pooled mortality risk: RR = 1.53 (IC 95%: [1.23-1.90]). This meta-analysis revealed a higher mortality in SSc patients with associated DUs. Having DUs may be a predictive factor of developing organ involvement such as pulmonary or cardiovascular events that could be associated with poor survival. It suggests that early screening of DUs in SSc patients is important to identify patients most at risk of poor survival. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Biopersistent Granular Dust and Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis

PubMed Central

Brüske, Irene; Thiering, Elisabeth; Heinrich, Joachim; Huster, Katharina; Nowak, Dennis

2013-01-01

Objective Applying a systematic review to identify studies eligible for meta-analysis of the association between occupational exposure to inorganic dust and the development of chronic obstructive pulmonary disease (COPD), and conducting a meta-analysis. Data Sources Searches of PubMed and Embase for the time period 1970–2010 yielded 257 cross-sectional and longitudinal studies on people exposed to inorganic dust at the workplace with data on lung function. These studies were independently abstracted and evaluated by two authors; any disagreement was resolved by a third reviewer. Of 55 publications accepted for meta-analysis, 27 investigated the effects of occupational exposure to biopersistent granular dust (bg-dust). Methods A random effects meta-analysis allowed us to provide an estimate of the average exposure effect on spirometric parameters presented in forest plots. Between-study heterogeneity was assessed by using I2 statistics, with I2>25% indicating significant heterogeneity. Publication bias was investigated by visual inspection of funnel plots. The influence of individual studies was assessed by dropping the respective study before pooling study-specific estimates. Results The mean FEV1 of workers exposed to bg-dust was 160 ml lower or 5.7% less than predicted compared to workers with no/low exposure. The risk of an obstructive airway disease—defined as FEV1/FVC < 70%—increased by 7% per 1 mg· m-3 respirable bg-dust. Conclusion Occupational inhalative exposure to bg-dust was associated with a statistically significant decreased FEV1 and FEV1/FVC revealing airway obstruction consistent with COPD. PMID:24278358

A general framework for the use of logistic regression models in meta-analysis.

PubMed

Simmonds, Mark C; Higgins, Julian Pt

2016-12-01

Where individual participant data are available for every randomised trial in a meta-analysis of dichotomous event outcomes, "one-stage" random-effects logistic regression models have been proposed as a way to analyse these data. Such models can also be used even when individual participant data are not available and we have only summary contingency table data. One benefit of this one-stage regression model over conventional meta-analysis methods is that it maximises the correct binomial likelihood for the data and so does not require the common assumption that effect estimates are normally distributed. A second benefit of using this model is that it may be applied, with only minor modification, in a range of meta-analytic scenarios, including meta-regression, network meta-analyses and meta-analyses of diagnostic test accuracy. This single model can potentially replace the variety of often complex methods used in these areas. This paper considers, with a range of meta-analysis examples, how random-effects logistic regression models may be used in a number of different types of meta-analyses. This one-stage approach is compared with widely used meta-analysis methods including Bayesian network meta-analysis and the bivariate and hierarchical summary receiver operating characteristic (ROC) models for meta-analyses of diagnostic test accuracy. © The Author(s) 2014.

Future time perspective: A systematic review and meta-analysis.

PubMed

Kooij, Dorien T A M; Kanfer, Ruth; Betts, Matt; Rudolph, Cort W

2018-04-23

The ability to foresee, anticipate, and plan for future desired outcomes is crucial for well-being, motivation, and behavior. However, theories in organizational psychology do not incorporate time-related constructs such as Future Time Perspective (FTP), and research on FTP remains disjointed and scattered, with different domains focusing on different aspects of the construct, using different measures, and assessing different antecedents and consequences. In this review and meta-analysis, we aim to clarify the FTP construct, advance its theoretical development, and demonstrate its importance by (a) integrating theory and empirical findings across different domains of research to identify major outcomes and antecedents of FTP, and (b) empirically examining whether and how these variables are moderated by FTP measures and dimensions. Results of a meta-analysis of k = 212 studies reveal significant relationships between FTP and major classes of consequences (i.e., those related to achievement, well-being, health behavior, risk behavior, and retirement planning), and between antecedents and FTP, as well as moderating effects of different FTP measures and dimensions. Highlighting the importance of FTP for organizational psychology theories, our findings demonstrate that FTP predicts these outcomes over and above the big five personality traits and mediates the associations between these personality traits and outcomes. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Methods to increase reproducibility in differential gene expression via meta-analysis

PubMed Central

Sweeney, Timothy E.; Haynes, Winston A.; Vallania, Francesco; Ioannidis, John P.; Khatri, Purvesh

2017-01-01

Findings from clinical and biological studies are often not reproducible when tested in independent cohorts. Due to the testing of a large number of hypotheses and relatively small sample sizes, results from whole-genome expression studies in particular are often not reproducible. Compared to single-study analysis, gene expression meta-analysis can improve reproducibility by integrating data from multiple studies. However, there are multiple choices in designing and carrying out a meta-analysis. Yet, clear guidelines on best practices are scarce. Here, we hypothesized that studying subsets of very large meta-analyses would allow for systematic identification of best practices to improve reproducibility. We therefore constructed three very large gene expression meta-analyses from clinical samples, and then examined meta-analyses of subsets of the datasets (all combinations of datasets with up to N/2 samples and K/2 datasets) compared to a ‘silver standard’ of differentially expressed genes found in the entire cohort. We tested three random-effects meta-analysis models using this procedure. We showed relatively greater reproducibility with more-stringent effect size thresholds with relaxed significance thresholds; relatively lower reproducibility when imposing extraneous constraints on residual heterogeneity; and an underestimation of actual false positive rate by Benjamini–Hochberg correction. In addition, multivariate regression showed that the accuracy of a meta-analysis increased significantly with more included datasets even when controlling for sample size. PMID:27634930

Sleep and mental disorders: A meta-analysis of polysomnographic research.

PubMed

Baglioni, Chiara; Nanovska, Svetoslava; Regen, Wolfram; Spiegelhalder, Kai; Feige, Bernd; Nissen, Christoph; Reynolds, Charles F; Riemann, Dieter

2016-09-01

Investigating sleep in mental disorders has the potential to reveal both disorder-specific and transdiagnostic psychophysiological mechanisms. This meta-analysis aimed at determining the polysomnographic (PSG) characteristics of several mental disorders. Relevant studies were searched through standard strategies. Controlled PSG studies evaluating sleep in affective, anxiety, eating, pervasive developmental, borderline and antisocial personality disorders, attention-deficit-hyperactivity disorder (ADHD), and schizophrenia were included. PSG variables of sleep continuity, depth, and architecture, as well as rapid-eye movement (REM) sleep were considered. Calculations were performed with the "Comprehensive Meta-Analysis" and "R" software. Using random effects modeling, for each disorder and each variable, a separate meta-analysis was conducted if at least 3 studies were available for calculation of effect sizes as standardized means (Hedges' g). Sources of variability, that is, sex, age, and mental disorders comorbidity, were evaluated in subgroup analyses. Sleep alterations were evidenced in all disorders, with the exception of ADHD and seasonal affective disorders. Sleep continuity problems were observed in most mental disorders. Sleep depth and REM pressure alterations were associated with affective, anxiety, autism and schizophrenia disorders. Comorbidity was associated with enhanced REM sleep pressure and more inhibition of sleep depth. No sleep parameter was exclusively altered in 1 condition; however, no 2 conditions shared the same PSG profile. Sleep continuity disturbances imply a transdiagnostic imbalance in the arousal system likely representing a basic dimension of mental health. Sleep depth and REM variables might play a key role in psychiatric comorbidity processes. Constellations of sleep alterations may define distinct disorders better than alterations in 1 single variable. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Self-objectification and disordered eating: A meta-analysis.

PubMed

Schaefer, Lauren M; Thompson, J Kevin

2018-06-01

Objectification theory posits that self-objectification increases risk for disordered eating. The current study sought to examine the relationship between self-objectification and disordered eating using meta-analytic techniques. Data from 53 cross-sectional studies (73 effect sizes) revealed a significant moderate positive overall effect (r = .39), which was moderated by gender, ethnicity, sexual orientation, and measurement of self-objectification. Specifically, larger effect sizes were associated with female samples and the Objectified Body Consciousness Scale. Effect sizes were smaller among heterosexual men and African American samples. Age, body mass index, country of origin, measurement of disordered eating, sample type and publication type were not significant moderators. Overall, results from the first meta-analysis to examine the relationship between self-objectification and disordered eating provide support for one of the major tenets of objectification theory and suggest that self-objectification may be a meaningful target in eating disorder interventions, though further work is needed to establish temporal and causal relationships. Findings highlight current gaps in the literature (e.g., limited representation of males, and ethnic and sexual minorities) with implications for guiding future research. © 2018 Wiley Periodicals, Inc.

Joint attention in Down syndrome: A meta-analysis.

PubMed

Hahn, Laura J; Loveall, Susan J; Savoy, Madison T; Neumann, Allie M; Ikuta, Toshikazu

2018-07-01

Some studies have indicated that joint attention may be a relative strength in Down syndrome (DS), but other studies have not. To conduct a meta-analysis of joint attention in DS to more conclusively determine if this is a relative strength or weakness when compared to children with typical development (TD), developmental disabilities (DD), and autism spectrum disorder (ASD). Journal articles published before September 13, 2016, were identified by using the search terms "Down syndrome" and "joint attention" or "coordinating attention". Identified studies were reviewed and coded for inclusion criteria, descriptive information, and outcome variables. Eleven studies (553 participants) met inclusion criteria. Children with DS showed similar joint attention as TD children and higher joint attention than children with DD and ASD. Meta-regression revealed a significant association between age and joint attention effect sizes in the DS vs. TD contrast. Joint attention appears to not be a weakness for children with DS, but may be commensurate with developmental level. Joint attention may be a relative strength in comparison to other skills associated with the DS behavioral phenotype. Early interventions for children with DS may benefit from leveraging joint attention skills. Copyright © 2018 Elsevier Ltd. All rights reserved.

The Meta-Aggregative Approach to Qualitative Evidence Synthesis: A Worked Example on Experiences of Pupils with Special Educational Needs in Inclusive Education

ERIC Educational Resources Information Center

Hannes, Karin; Petry, Katja; Heyvaert, Mieke

2018-01-01

The present article focuses on the meta-aggregative approach to qualitative evidence synthesis. Originally developed in Australia by the Joanna Briggs Institute, it mirrors the review process for reviews of effectiveness outlined by the international Cochrane and Campbell Collaboration, while remaining sensitive to the specific characteristics of…

Meta-analysis reveals a lack of sexual dimorphism in human amygdala volume.

PubMed

Marwha, Dhruv; Halari, Meha; Eliot, Lise

2017-02-15

The amygdala plays a key role in many affective behaviors and psychiatric disorders that differ between men and women. To test whether human amygdala volume (AV) differs reliably between the sexes, we performed a systematic review and meta-analysis of AVs reported in MRI studies of age-matched healthy male and female groups. Using four search strategies, we identified 46 total studies (58 matched samples) from which we extracted effect sizes for the sex difference in AV. All data were converted to Hedges g values and pooled effect sizes were calculated using a random-effects model. Each dataset was further meta-regressed against study year and average participant age. We found that uncorrected amygdala volume is about 10% larger in males, with pooled sex difference effect sizes of g=0.581 for right amygdala (κ=28, n=2022), 0.666 for left amygdala (κ=28, n=2006), and 0.876 for bilateral amygdala (κ=16, n=1585) volumes (all p values < 0.001). However, this difference is comparable to the sex differences in intracranial volume (ICV; g=1.186, p<.001, 11.9% larger in males, κ=11) and total brain volume (TBV; g=1.278, p<0.001, 11.5% larger in males, κ=15) reported in subsets of the same studies, suggesting the sex difference in AV is a product of larger brain size in males. Among studies reporting AVs normalized for ICV or TBV, sex difference effect sizes were small and not statistically significant: g=0.171 for the right amygdala (p=0.206, κ=13, n=1560); 0.233 for the left amygdala (p=0.092, κ=12, n=1512); and 0.257 for bilateral volume (p=0.131, κ=5, n=1629). These values correspond to less than 0.1% larger corrected right AV and 2.5% larger corrected left AV in males compared to females. In summary, AV is not selectively enhanced in human males, as often claimed. Although we cannot rule out subtle male-female group differences, it is not accurate to refer to the human amygdala as "sexually dimorphic." Copyright © 2016 Elsevier Inc. All rights reserved.

Computerized lung sound analysis as diagnostic aid for the detection of abnormal lung sounds: a systematic review and meta-analysis.

PubMed

Gurung, Arati; Scrafford, Carolyn G; Tielsch, James M; Levine, Orin S; Checkley, William

2011-09-01

The standardized use of a stethoscope for chest auscultation in clinical research is limited by its inherent inter-listener variability. Electronic auscultation and automated classification of recorded lung sounds may help prevent some of these shortcomings. We sought to perform a systematic review and meta-analysis of studies implementing computerized lung sound analysis (CLSA) to aid in the detection of abnormal lung sounds for specific respiratory disorders. We searched for articles on CLSA in MEDLINE, EMBASE, Cochrane Library and ISI Web of Knowledge through July 31, 2010. Following qualitative review, we conducted a meta-analysis to estimate the sensitivity and specificity of CLSA for the detection of abnormal lung sounds. Of 208 articles identified, we selected eight studies for review. Most studies employed either electret microphones or piezoelectric sensors for auscultation, and Fourier Transform and Neural Network algorithms for analysis and automated classification of lung sounds. Overall sensitivity for the detection of wheezes or crackles using CLSA was 80% (95% CI 72-86%) and specificity was 85% (95% CI 78-91%). While quality data on CLSA are relatively limited, analysis of existing information suggests that CLSA can provide a relatively high specificity for detecting abnormal lung sounds such as crackles and wheezes. Further research and product development could promote the value of CLSA in research studies or its diagnostic utility in clinical settings. Copyright © 2011 Elsevier Ltd. All rights reserved.

Systematic Review and Meta-Analysis of Patiromer and Sodium Zirconium Cyclosilicate: A New Armamentarium for the Treatment of Hyperkalemia

PubMed Central

Meaney, Calvin J.; Beccari, Mario V.; Yang, Yang; Zhao, Jiwei

2017-01-01

Objective To compare and contrast the efficacy and safety of patiromer and sodium zirconium cyclosilicate (ZS-9) in the treatment of hyperkalemia. Design A systematic review and meta-analysis of phase II and III clinical trial data was completed. Patients or Participants Eight studies (2 phase II and 4 phase III trials with 2 subgroup analyses) were included in the qualitative analysis whereas six studies (2 phase II and 4 phase III trials) were included in the meta-analysis. Measurements and Results There was significant heterogeneity in the meta-analysis with an I2 value ranging from 80.6–99.6%. A random-effects meta-analysis was applied for all endpoints. Each clinical trial stratified results by hyperkalemia severity and dosing; therefore, these were considered separate treatment groups in the meta-analysis. For patiromer, there was a significant −0.70mEq/L (95% confidence interval [CI] −0.48 to −0.91mEq/L) change in potassium at 4 weeks. At day 3 of patiromer treatment, potassium change was −0.36mEq/L (range of standard deviation: 0.07 to 0.30). The primary endpoint for ZS-9-- change in potassium at 48 hours-- was −0.67mEq/L (95% CI −0.45 to −0.89mEq/L). By 1 hour after ZS-9 administration, change in potassium was −0.17mEq/L (95% CI −0.05 to −0.30). Analysis of pooled adverse effects from these trials indicates that patiromer was associated with more gastrointestinal upset (7.6% constipation, 4.5% diarrhea) and electrolyte depletion (7.1% hypomagnesemia), whereas ZS-9 was associated with adverse effects of urinary tract infections (1.1%) and edema (0.9%). Conclusion Patiromer and ZS-9 represent significant pharmacologic advancements in the treatment of hyperkalemia. Both agents exhibited statistically and clinically significant reductions in potassium for the primary endpoint of this meta-analysis. Given the adverse effect profile and the observed time dependent effects, ZS-9 may play more of a role in treating acute hyperkalemia. PMID

Methods for the Joint Meta-Analysis of Multiple Tests

ERIC Educational Resources Information Center

Trikalinos, Thomas A.; Hoaglin, David C.; Small, Kevin M.; Terrin, Norma; Schmid, Christopher H.

2014-01-01

Existing methods for meta-analysis of diagnostic test accuracy focus primarily on a single index test. We propose models for the joint meta-analysis of studies comparing multiple index tests on the same participants in paired designs. These models respect the grouping of data by studies, account for the within-study correlation between the tests'…

Meta-analysis: Problems with Russian Publications.

PubMed

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

Does Hands-On Science Practices Make an Impact on Achievement in Science? A Meta-Analysis

ERIC Educational Resources Information Center

Caglak, Serdar

2017-01-01

This study aimed to investigate to what extent the use of hands-on science activities influences on students? academic achievement in science. Review of literature revealed several research studies focusing upon such aim and thus, a meta-analysis of these researches was carried out to obtain an overall effect size estimate of hands-on science…

Network meta-analysis in health psychology and behavioural medicine: a primer.

PubMed

Molloy, G J; Noone, C; Caldwell, D; Welton, N J; Newell, J

2018-04-05

Progress in the science and practice of health psychology depends on the systematic synthesis of quantitative psychological evidence. Meta-analyses of experimental studies have led to important advances in understanding health-related behaviour change interventions. Fundamental questions regarding such interventions have been systematically investigated through synthesising relevant experimental evidence using standard pairwise meta-analytic procedures that provide reliable estimates of the magnitude, homogeneity and potential biases in effects observed. However, these syntheses only provide information about whether particular types of interventions work better than a control condition or specific alternative approaches. To increase the impact of health psychology on health-related policy-making, evidence regarding the comparative efficacy of all relevant intervention approaches - which may include biomedical approaches - is necessary. With the development of network meta-analysis (NMA), such evidence can be synthesised, even when direct head-to-head trials do not exist. However, care must be taken in its application to ensure reliable estimates of the effect sizes between interventions are revealed. This review paper describes the potential importance of NMA to health psychology, how the technique works and important considerations for its appropriate application within health psychology.

Meta-analysis and meta-regression analysis of outcomes of carotid endarterectomy and stenting in the elderly.

PubMed

Antoniou, George A; Georgiadis, George S; Georgakarakos, Efstratios I; Antoniou, Stavros A; Bessias, Nikos; Smyth, John Vincent; Murray, David; Lazarides, Miltos K

2013-12-01

Uncertainty exists about the influence of advanced age on the outcomes of carotid revascularization. To undertake a comprehensive review of the literature and conduct an analysis of the outcomes of carotid interventions in the elderly. A systematic literature review was conducted to identify articles comparing early outcomes of carotid endarterectomy (CEA) or carotid stenting (CAS) in elderly and young patients. Combined overall effect sizes were calculated using fixed or random effects models. Meta-regression models were formed to explore potential heterogeneity as a result of changes in practice over time. RESULTS Our analysis comprised 44 studies reporting data on 512,685 CEA and 75,201 CAS procedures. Carotid stenting was associated with increased incidence of stroke in elderly patients compared with their young counterparts (odds ratio [OR], 1.56; 95% CI, 1.40-1.75), whereas CEA had equivalent cerebrovascular outcomes in old and young age groups (OR, 0.94; 95% CI, 0.88-0.99). Carotid stenting had similar peri-interventional mortality risks in old and young patients (OR, 0.86; 95% CI, 0.72-1.03), whereas CEA was associated with heightened mortality in elderly patients (OR, 1.62; 95% CI, 1.47-1.77). The incidence of myocardial infarction was increased in patients of advanced age in both CEA and CAS (OR, 1.64; 95% CI, 1.57-1.72 and OR, 1.30; 95% CI, 1.16-1.45, respectively). Meta-regression analyses revealed a significant effect of publication date on peri-interventional stroke (P = .003) and mortality (P < .001) in CAS. Age should be considered when planning a carotid intervention. Carotid stenting has an increased risk of adverse cerebrovascular events in elderly patients but mortality equivalent to younger patients. Carotid endarterectomy is associated with similar neurologic outcomes in elderly and young patients, at the expense of increased mortality.

Antibiotic Resistance in Food Animals in Africa: A Systematic Review and Meta-Analysis.

PubMed

Founou, Luria Leslie; Amoako, Daniel Gyamfi; Founou, Raspail Carrel; Essack, Sabiha Yusuf

2018-06-01

This study critically reviewed the published literature and performed a meta-analysis to determine the overall burden of antibiotic-resistant bacteria in food animals in Africa. English and French published articles indexed in EBSCOhost, PubMed, Web of Science, and African Journals Online were retrieved, with searches being conducted up to August, 2015. Data were pooled and meta-analysis performed using a random-effects model, and the results are described as event rates. According to the predefined inclusion and exclusion criteria, 17 articles out of the 852 retrieved were eligible for the qualitative and quantitative analysis. The studies included were mainly conducted in Nigeria, with Escherichia coli, Salmonella spp., and Campylobacter spp. being the main bacteria. The pooled estimates showed high level of antibiotic resistance (ABR) (86%; p < 0.001) and multidrug resistance (73%; p = 0.003). Our results suggest that ABR is substantively prevalent and poses a serious threat for food safety and security in Africa. These findings shed light on areas for future research concerning antibiotic-resistant and multidrug-resistant bacteria in food animals as etiological agents of infectious diseases in humans. They further yielded some interesting findings on the burden of ABR that could be useful in developing measures to contain this threat in the farm-to-plate continuum in Africa.

Meta-Analysis for Sociology – A Measure-Driven Approach

PubMed Central

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

Multivariate meta-analysis using individual participant data

PubMed Central

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

2016-01-01

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 that within-study correlations needed to fit the multivariate model are unknown from published reports. However, provision of individual participant data (IPD) allows them to be calculated directly. Here, we illustrate how to use IPD to estimate within-study correlations, using a joint linear regression for multiple continuous outcomes and bootstrapping methods for binary, survival and mixed outcomes. In a meta-analysis of 10 hypertension trials, we then show how these methods enable multivariate meta-analysis to address novel clinical questions about continuous, survival and binary outcomes; treatment–covariate interactions; adjusted risk/prognostic factor effects; longitudinal data; prognostic and multiparameter models; and multiple treatment comparisons. Both frequentist and Bayesian approaches are applied, with example software code provided to derive within-study correlations and to fit the models. PMID:26099484

Evaluating the Effect of Virtual Reality Temporal Bone Simulation on Mastoidectomy Performance: A Meta-analysis.

PubMed

Lui, Justin T; Hoy, Monica Y

2017-06-01

Background The increasing prevalence of virtual reality simulation in temporal bone surgery warrants an investigation to assess training effectiveness. Objectives To determine if temporal bone simulator use improves mastoidectomy performance. Data Sources Ovid Medline, Embase, and PubMed databases were systematically searched per the PRISMA guidelines. Review Methods Inclusion criteria were peer-reviewed publications that utilized quantitative data of mastoidectomy performance following the use of a temporal bone simulator. The search was restricted to human studies published in English. Studies were excluded if they were in non-peer-reviewed format, were descriptive in nature, or failed to provide surgical performance outcomes. Meta-analysis calculations were then performed. Results A meta-analysis based on the random-effects model revealed an improvement in overall mastoidectomy performance following training on the temporal bone simulator. A standardized mean difference of 0.87 (95% CI, 0.38-1.35) was generated in the setting of a heterogeneous study population ( I 2 = 64.3%, P < .006). Conclusion In the context of a diverse population of virtual reality simulation temporal bone surgery studies, meta-analysis calculations demonstrate an improvement in trainee mastoidectomy performance with virtual simulation training.

Internet and computer based interventions for cannabis use: a meta-analysis.

PubMed

Tait, Robert J; Spijkerman, Renske; Riper, Heleen

2013-12-01

Worldwide, cannabis is the most prevalently used illegal drug and creates demand for prevention and treatment services that cannot be fulfilled using conventional approaches. Computer and Internet-based interventions may have the potential to meet this need. Therefore, we systematically reviewed the literature and conducted a meta-analysis on the effectiveness of this approach in reducing the frequency of cannabis use. We systematically searched online databases (Medline, PubMed, PsychINFO, Embase) for eligible studies and conducted a meta-analysis. Studies had to use a randomized design, be delivered either via the Internet or computer and report separate outcomes for cannabis use. The principal outcome measure was the frequency of cannabis use. Data were extracted from 10 studies and the meta-analysis involved 10 comparisons with 4,125 participants. The overall effect size was small but significant, g=0.16 (95% confidence interval (CI) 0.09-0.22, P<0.001) at post-treatment. Subgroup analyses did not reveal significant subgroup differences for key factors including type of analysis (intention-to-treat, completers only), type of control (active, waitlist), age group (11-16, 17+ years), gender composition (female only, mixed), type of intervention (prevention, 'treatment'), guided versus unguided programs, mode of delivery (Internet, computer), individual versus family dyad and venue (home, research setting). Also, no significant moderation effects were found for number of sessions and time to follow-up. Finally, there was no evidence of publication bias. Internet and computer interventions appear to be effective in reducing cannabis use in the short-term albeit based on data from few studies and across diverse samples. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

How acute total sleep loss affects the attending brain: a meta-analysis of neuroimaging studies.

PubMed

Ma, Ning; Dinges, David F; Basner, Mathias; Rao, Hengyi

2015-02-01

Attention is a cognitive domain that can be severely affected by sleep deprivation. Previous neuroimaging studies have used different attention paradigms and reported both increased and reduced brain activation after sleep deprivation. However, due to large variability in sleep deprivation protocols, task paradigms, experimental designs, characteristics of subject populations, and imaging techniques, there is no consensus regarding the effects of sleep loss on the attending brain. The aim of this meta-analysis was to identify brain activations that are commonly altered by acute total sleep deprivation across different attention tasks. Coordinate-based meta-analysis of neuroimaging studies of performance on attention tasks during experimental sleep deprivation. The current version of the activation likelihood estimation (ALE) approach was used for meta-analysis. The authors searched published articles and identified 11 sleep deprivation neuroimaging studies using different attention tasks with a total of 185 participants, equaling 81 foci for ALE analysis. The meta-analysis revealed significantly reduced brain activation in multiple regions following sleep deprivation compared to rested wakefulness, including bilateral intraparietal sulcus, bilateral insula, right prefrontal cortex, medial frontal cortex, and right parahippocampal gyrus. Increased activation was found only in bilateral thalamus after sleep deprivation compared to rested wakefulness. Acute total sleep deprivation decreases brain activation in the fronto-parietal attention network (prefrontal cortex and intraparietal sulcus) and in the salience network (insula and medial frontal cortex). Increased thalamic activation after sleep deprivation may reflect a complex interaction between the de-arousing effects of sleep loss and the arousing effects of task performance on thalamic activity. © 2015 Associated Professional Sleep Societies, LLC.

An innovative and comprehensive technique to evaluate different measures of medication adherence: The network meta-analysis.

PubMed

Tonin, Fernanda S; Wiecek, Elyssa; Torres-Robles, Andrea; Pontarolo, Roberto; Benrimoj, Shalom Charlie I; Fernandez-Llimos, Fernando; Garcia-Cardenas, Victoria

2018-05-19

Poor medication adherence is associated with adverse health outcomes and higher costs of care. However, inconsistencies in the assessment of adherence are found in the literature. To evaluate the effect of different measures of adherence in the comparative effectiveness of complex interventions to enhance patients' adherence to prescribed medications. A systematic review with network meta-analysis was performed. Electronic searches for relevant pairwise meta-analysis including trials of interventions that aimed to improve medication adherence were performed in PubMed. Data extraction was conducted with eligible trials evaluating short-period adherence follow-up (until 3 months) using any measure of adherence: self-report, pill count, or MEMS (medication event monitoring system). To standardize the results obtained with these different measures, an overall composite measure and an objective composite measure were also calculated. Network meta-analyses for each measure of adherence were built. Rank order and surface under the cumulative ranking curve analyses (SUCRA) were performed. Ninety-one trials were included in the network meta-analyses. The five network meta-analyses demonstrated robustness and reliability. Results obtained for all measures of adherence were similar across them and to both composite measures. For both composite measures, interventions comprising economic + technical components were the best option (90% of probability in SUCRA analysis) with statistical superiority against almost all other interventions and against standard care (odds ratio with 95% credibility interval ranging from 0.09 to 0.25 [0.02, 0.98]). The use of network meta-analysis was reliable to compare different measures of adherence of complex interventions in short-periods follow-up. Analyses with longer follow-up periods are needed to confirm these results. Different measures of adherence produced similar results. The use of composite measures revealed reliable alternatives

Binary similarity measures for fingerprint analysis of qualitative metabolomic profiles.

PubMed

Rácz, Anita; Andrić, Filip; Bajusz, Dávid; Héberger, Károly

2018-01-01

Contemporary metabolomic fingerprinting is based on multiple spectrometric and chromatographic signals, used either alone or combined with structural and chemical information of metabolic markers at the qualitative and semiquantitative level. However, signal shifting, convolution, and matrix effects may compromise metabolomic patterns. Recent increase in the use of qualitative metabolomic data, described by the presence (1) or absence (0) of particular metabolites, demonstrates great potential in the field of metabolomic profiling and fingerprint analysis. The aim of this study is a comprehensive evaluation of binary similarity measures for the elucidation of patterns among samples of different botanical origin and various metabolomic profiles. Nine qualitative metabolomic data sets covering a wide range of natural products and metabolomic profiles were applied to assess 44 binary similarity measures for the fingerprinting of plant extracts and natural products. The measures were analyzed by the novel sum of ranking differences method (SRD), searching for the most promising candidates. Baroni-Urbani-Buser (BUB) and Hawkins-Dotson (HD) similarity coefficients were selected as the best measures by SRD and analysis of variance (ANOVA), while Dice (Di1), Yule, Russel-Rao, and Consonni-Todeschini 3 ranked the worst. ANOVA revealed that concordantly and intermediately symmetric similarity coefficients are better candidates for metabolomic fingerprinting than the asymmetric and correlation based ones. The fingerprint analysis based on the BUB and HD coefficients and qualitative metabolomic data performed equally well as the quantitative metabolomic profile analysis. Fingerprint analysis based on the qualitative metabolomic profiles and binary similarity measures proved to be a reliable way in finding the same/similar patterns in metabolomic data as that extracted from quantitative data.

Cognitive deficits in individuals with methamphetamine use disorder: A meta-analysis.

PubMed

Potvin, Stéphane; Pelletier, Julie; Grot, Stéphanie; Hébert, Catherine; Barr, Alasdair M; Lecomte, Tania

2018-05-01

Methamphetamine has long been considered as a neurotoxic substance causing cognitive deficits. Recently, however, the magnitude and the clinical significance of the cognitive effects associated with methamphetamine use disorder (MUD) have been debated. To help clarify this controversy, we performed a meta-analysis of the cognitive deficits associated with MUD. A literature search yielded 44 studies that assessed cognitive dysfunction in 1592 subjects with MUD and 1820 healthy controls. Effect size estimates were calculated using the Comprehensive Meta-Analysis, for the following 12 cognitive domains: attention, executive functions, impulsivity/reward processing, social cognition, speed of processing, verbal fluency/language, verbal learning and memory, visual learning and memory, visuo-spatial abilities and working memory. Findings revealed moderate impairment across most cognitive domains, including attention, executive functions, language/verbal fluency, verbal learning and memory, visual memory and working memory. Deficits in impulsivity/reward processing and social cognition were more prominent, whereas visual learning and visuo-spatial abilities were relatively spared cognitive domains. A publication bias was observed. These results show that MUD is associated with broad cognitive deficits that are in the same range as those associated with alcohol and cocaine use disorder, as recently shown by way of meta-analysis. The prominent effects of MUD on social cognition and impulsivity/reward processing are based on a small number of studies, and as such, these results will need to be replicated. The functional consequences (social and occupational) of the cognitive deficits of methamphetamine will also need to be determined. Copyright © 2018 Elsevier Ltd. All rights reserved.

Mortality and cancer morbidity among cement production workers: a meta-analysis.

PubMed

Donato, Francesca; Garzaro, Giacomo; Pira, Enrico; Boffetta, Paolo

2016-11-01

To analyze overall and cause-specific mortality, especially from cancer, among cement production workers. Results from some epidemiological studies suggested an increased risk of overall mortality and of stomach cancer associated with employment in the cement production, but the presence of a hazard and, if present, the magnitude of a risk have not been precisely quantified. We conducted a systematic review and meta-analysis of data on mortality from all causes, cardiovascular or respiratory diseases, and cancer among cement workers. The literature search in PubMed and Scopus up to February 2016 and with appropriate keywords on mortality among cement workers revealed 188 articles which were screened. A total of 117 articles were reviewed in full text and 12 articles, referring to 11 study populations, were found to be relevant and of sufficient quality for further analysis. Meta-analyses were performed using a random-effects model. Eight cohort studies, one proportionate mortality study, and two case-control studies were identified. The summary RRs were 0.89 [95 % confidence interval (CI) 0.76-1.01] for all-cause mortality, 0.94 (95 %, CI 0.80-1.08) for cancer mortality, 1.07 (95 % CI 0.79-1.35) for lung cancer mortality, and 0.93 (95 % CI 0.70-1.17) for stomach cancer mortality, respectively. Significant heterogeneity in results was observed among studies. The present meta-analysis does not provide evidence of increased risk of overall mortality, as well as cancer, cardiovascular or respiratory mortality in relation to employment in cement production.

Effectiveness of training in organizations: a meta-analysis of design and evaluation features.

PubMed

Arthur, Winfred; Bennett, Winston; Edens, Pamela S; Bell, Suzanne T

2003-04-01

The authors used meta-analytic procedures to examine the relationship between specified training design and evaluation features and the effectiveness of training in organizations. Results of the meta-analysis revealed training effectiveness sample-weighted mean ds of 0.60 (k = 15, N = 936) for reaction criteria, 0.63 (k = 234, N = 15,014) for learning criteria, 0.62 (k = 122, N = 15,627) for behavioral criteria, and 0.62 (k = 26, N = 1,748) for results criteria. These results suggest a medium to large effect size for organizational training. In addition, the training method used, the skill or task characteristic trained, and the choice of evaluation criteria were related to the effectiveness of training programs. Limitations of the study along with suggestions for future research are discussed.

Non-resurfacing techniques in the management of the patella at total knee arthroplasty: A systematic review and meta-analysis.

PubMed

Findlay, I; Wong, F; Smith, C; Back, D; Davies, A; Ajuied, A

2016-03-01

Recent meta-analyses support not resurfacing the patella at the time of TKA. Several different modes of intervention are reported for non-resurfacing management of the patella at TKA. We have conducted a systematic review and meta-analysis of non-resurfacing interventions in TKA. The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) study methodology and reporting system was adopted, utilising the PRISMA checklist and statement. Classes of patella interventions were defined as: 0. No intervention. 1. Osteophyte excision only. 2. Osteophyte excision, denervation, with soft tissue debridement. 3. Osteophyte excision, denervation, soft tissue debridement, and drilling or micro-fracture of eburnated bone. 4. Patellar resurfacing. A meta-analysis was conducted upon the pre- and post-operative KSS for each technique. Four hundred and twenty-three studies were identified, 12 studies met the inclusion criteria for the systematic review and eight for the meta-analysis. Two studies compared different non-resurfacing patellar techniques, the other studies used the non-resurfacing cohort as controls for their prospective RCTs comparing patellar resurfacing with non-resurfacing. The meta-analysis revealed no significant difference between the techniques. We conclude that there is no significant difference in KSS for differing non-resurfacing patellar techniques, but further trials using patellofemoral specific scores may better demonstrate superior efficacy of specific classes of patella intervention, by virtue of greater sensitivity for patellofemoral pain and dysfunction. I. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

Association between air pollution and sperm quality: A systematic review and meta-analysis.

PubMed

Deng, Zibing; Chen, Fei; Zhang, Meixia; Lan, Lan; Qiao, Zhijiao; Cui, Yan; An, Jinghuan; Wang, Nan; Fan, Zhiwei; Zhao, Xing; Li, Xiaosong

2016-01-01

Exposure to ambient air pollution has been clearly linked to adverse reproductive outcome and fecundation index, but its effects on male semen quality are still uncertain. In this study, we reviewed information from ten studies to get the qualitative evidence of the influence of the ambient air pollution on sperm quality and collected data from six of the ten studies to conduct meta-analysis. The original studies classified participants into different exposure levels and the highest and lowest expose levels were chosen as high expose and low expose groups, respectively. The random-effect model was used in the meta-analysis with the weight mean difference (WMD) as the measure indicator. The WMDs (95% confidence intervals, CIs) of sperm volume, sperm count, semen concentration, sperm progressive motility, total motility, and normal morphology were 0.09 (-0.04, 0.23), 0.46 (-4.47, 5.39), -8.21 (-20.38, 3.96), -7.76 (-16.26, 0.74), -7.61 (-16.97, 1.74) and -3.40 (-7.42, 0.62), respectively. In conclusion, although the differences are not statistically significant between the two groups, the overall trends and evidence from this review indicate the chronic exposure to ambient pollutants at high level may alter men sperm quality. Copyright © 2015 Elsevier Ltd. All rights reserved.

GWAR: robust analysis and meta-analysis of genome-wide association studies.

PubMed

Dimou, Niki L; Tsirigos, Konstantinos D; Elofsson, Arne; Bagos, Pantelis G

2017-05-15

In the context of genome-wide association studies (GWAS), there is a variety of statistical techniques in order to conduct the analysis, but, in most cases, the underlying genetic model is usually unknown. Under these circumstances, the classical Cochran-Armitage trend test (CATT) is suboptimal. Robust procedures that maximize the power and preserve the nominal type I error rate are preferable. Moreover, performing a meta-analysis using robust procedures is of great interest and has never been addressed in the past. The primary goal of this work is to implement several robust methods for analysis and meta-analysis in the statistical package Stata and subsequently to make the software available to the scientific community. The CATT under a recessive, additive and dominant model of inheritance as well as robust methods based on the Maximum Efficiency Robust Test statistic, the MAX statistic and the MIN2 were implemented in Stata. Concerning MAX and MIN2, we calculated their asymptotic null distributions relying on numerical integration resulting in a great gain in computational time without losing accuracy. All the aforementioned approaches were employed in a fixed or a random effects meta-analysis setting using summary data with weights equal to the reciprocal of the combined cases and controls. Overall, this is the first complete effort to implement procedures for analysis and meta-analysis in GWAS using Stata. A Stata program and a web-server are freely available for academic users at http://www.compgen.org/tools/GWAR. pbagos@compgen.org. Supplementary data are available at Bioinformatics online. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

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

PubMed Central

Rücker, Gerta; Schumacher, Martin

2008-01-01

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. PMID:18513392

An epigenome-wide association meta-analysis of prenatal maternal stress in neonates: A model approach for replication

PubMed Central

Rijlaarsdam, Jolien; Pappa, Irene; Walton, Esther; Bakermans-Kranenburg, Marian J.; Mileva-Seitz, Viara R.; Rippe, Ralph C.A.; Roza, Sabine J.; Jaddoe, Vincent W.V.; Verhulst, Frank C.; Felix, Janine F.; Cecil, Charlotte A.M.; Relton, Caroline L.; Gaunt, Tom R.; McArdle, Wendy; Mill, Jonathan; Barker, Edward D.; Tiemeier, Henning; van IJzendoorn, Marinus H.

2016-01-01

ABSTRACT Prenatal maternal stress exposure has been associated with neonatal differential DNA methylation. However, the available evidence in humans is largely based on candidate gene methylation studies, where only a few CpG sites were evaluated. The aim of this study was to examine the association between prenatal exposure to maternal stress and offspring genome-wide cord blood methylation using different methods. First, we conducted a meta-analysis and follow-up pathway analyses. Second, we used novel region discovery methods [i.e., differentially methylated regions (DMRs) analyses]. To this end, we used data from two independent population-based studies, the Generation R Study (n = 912) and the Avon Longitudinal Study of Parents and Children (ALSPAC, n = 828), to (i) measure genome-wide DNA methylation in cord blood and (ii) extract a prenatal maternal stress composite. The meta-analysis (ntotal = 1,740) revealed no epigenome-wide (meta P <1.00e-07) associations of prenatal maternal stress exposure with neonatal differential DNA methylation. Follow-up analyses of the top hits derived from our epigenome-wide meta-analysis (meta P <1.00e-04) indicated an over-representation of the methyltransferase activity pathway. We identified no Bonferroni-corrected (P <1.00e-06) DMRs associated with prenatal maternal stress exposure. Combining data from two independent population-based samples in an epigenome-wide meta-analysis, the current study indicates that there are no large effects of prenatal maternal stress exposure on neonatal DNA methylation. Such replication efforts are essential in the search for robust associations, whether derived from candidate gene methylation or epigenome-wide studies. PMID:26889969

Individualized Positive Behavior Support in School Settings: A Meta-Analysis

ERIC Educational Resources Information Center

Goh, Ailsa E.; Bambara, Linda M.

2012-01-01

This meta-analysis examined school-based intervention research based on functional behavioral assessment (FBA) to determine the effectiveness of key individualized positive behavior support (IPBS) practices in school settings. In all, 83 studies representing 145 participants were included in the meta-analysis. Intervention, maintenance, and…

Science education: A meta-analysis of major questions

NASA Astrophysics Data System (ADS)

Anderson, Ronald D.; Kahl, Stuart R.; Glass, Gene V.; Smith, Mary Lee

A multi-institutional endeavor was initiated to integrate the findings of extant research studies directed toward the major science education research questions. The research questions were selected by a largely empirical process of identifiying the most frequently researched questions in the literature. These questions were assigned to various researchers who developed coding sheets and procedures with many features in common. This article describes the overall operation of the project, the research questions identified, and some rudiments of meta-analysis. The results of the several meta-analysis are reported in the other articles of this issue of the Journal. The final article in this issue deals with research topics for which data are drawn from one or more of the separate meta-analyses.

A Meta-Analysis of 25 Years of Mood-Creativity Research: Hedonic Tone, Activation, or Regulatory Focus?