InterIeukin-6 polymorphisms modify the risk of periodontitis: a systematic review and meta-analysis

Objective: To clarify the association of IL-6 polymorphisms and periodontitis, a meta-analysis of case-control studies and a systemic review were conducted. Material and methods: We performed a literature search using PubMed and Medline database to May 2009, with no restrictions. We also reviewed referebces from all retrieved articles. Six case-control studies involving 1093 periodontitis cases and 574 controls were selected for meta-analysis to assess the purported associations between IL-6 polymorphisms and the risk of periodontitis. IL-6 -174 G/C and -572 C/G polymorphisms were included in the present meta-analysis, and the association between IL-6 -6331 T/C polymorphism and the risk of periodontitis was adequately reviewed as well. Results and conclusion: The present meta-analysis indicates that the IL-6 -174 G allele could not modify the risk of chronic periodontitis, but increased the risk of aggressive periodontitis. And -572 C/G polymorphism is associated with the pathogenesis of periodontitis, including chronic periodontitis or aggressive periodontitis.     

The impacts of family treatment drug court on child welfare core outcomes: A meta-analysis

BackgroundSubstance abuse has been prevalent among caregivers involved in child welfare and is a major barrier to their achieving favorable outcomes. Family Treatment Drug Courts (FTDCs) have been viewed as one of the most promising interventions but research has reported mixed effects on child welfare outcomes. No meta-analysis was conducted to synthesize the findings to reach a more generalizable conclusion.ObjectiveThe meta-analysis synthesized findings from existing evaluations to examine whether and to what extent FTDC participants achieved better reunification and safety outcomes than non-participants.Participants and SettingAmong 17 identified studies dated from 2004 to 2018, the pooled sample subjects in the intervention and comparison groups were 3402 and 3683 for the 16 studies on reunification outcomes, and 842 and 632 for the eight studies on child safety outcomes.MethodsWe first estimated the FTDCs’ pooled effects on child reunification and safety outcomes. Furthermore, we conducted a series of subgroup meta-analysis to compare FTDCs’ effects across study and program characteristics.ResultsSubjects participating in FTDCs were substantially more likely to achieve reunification (OR = 1.75, 95% CI = 1.38, 2.22) without increasing the risk of subsequent foster care reentry or maltreatment re-report. Subgroup meta-analysis suggests factors such as research design, FTDC model, observation length, publication type and period may contribute to FTDCs’ disparities on reunification outcomes.ConclusionsThe synthesized findings strengthen evidence for the implementation and expansion of FTDCs for serving substance abusing caregivers in the child welfare system.     

Technology-enhanced mathematics instruction: A second-order meta-analysis of 30 years of research

It is important to assess the cumulative effects of technology on student achievement captured in the last 30 years of technologyenhanced mathematics instruction. Synthesizing the thousands of articles and gray literature on this subject is necessary but would require a considerable commitment of academic resources. A second-order metaanalysis or meta-analysis of meta-analyses is an alternative that is reasonable and effective. Thus, a second-order meta-analysis of 19 prior meta-analyses with minimum overlap between primary studies was conducted. The results represent 663 primary studies (approximately 141,733 participants) and 1,263 effect sizes. The random effects' mean effect size of .38 was statistically significantly different from zero. The results provide a historical and contextualized summary of 30 years of meta-analytic research, which supports meta-analytic thinking and better interpretation of future effect sizes. Results indicate that technology function and study quality are major contributors to effect size variation. Specifically, computation enhancement technologies were most effective, while studies that examine combinations of enhancements were least effective. Implications for technology-enhanced mathematics instruction and meta-analytic research are provided.     

Moving Beyond “It worked”: The Ongoing Evolution of Research on Problem-Based Learning in Medical Education

Research on Problem-Based Learning in medical education has undergone an evolutionary process from initial proof of concept studies through critiques of the original methods and beyond. Initial studies focused on whether or not the instructional method was effective for medical students and the goals of medical education. Despite much movement back and forth between results demonstrating effectiveness and ineffectiveness, not much forward progress was made in reaching a decisive conclusion. Recently, however, the adoption of different theoretical perspectives, research methods, research targets and technological supports has begun to move the studies along. Current research in the area is focusing not on whether the students learn, but rather what goes on during learning that helps or hinders their learning. As such the group process and its cognitive components has become a more fruitful target of researchers. An erratum to this article can be found at     

Adding results to a meta-analysis: Theory and example

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.     

Detecting potential hucksterism in meta-analysis using a follow-up fail-safe test

Meta-analysis is an analysis of analyses. It is a technique widely used by researchers and practitioners to aggregate and summarize statistically reported empirical educational research. In 10 years, meta-analysis appeared more than 600 times in research journals and dissertation abstracts. Although most meta-analyses were reported as significant, few of the findings determined how many unpublished “no-effect” studies, if sampled, would have invalidated significance. If significant meta-analysis results are over represented through selective sampling, hucksterism in the form of sampling bias exists. An explanation for using a follow-up test called the fail-safe N is provided with tables constructed to assist researchers and practitioners to estimate, without calculation, the relative stability of meta-analysis results. The implication is that failsafe N should routinely be used and reported in meta-analysis research.     

The Effects of Test Accommodations for English Language Learners: A Meta-Analysis

A meta-analysis using Hierarchical Linear Modeling (HLM) was conducted to examine the effects of test accommodations on the test performance of English language learners (ELLs). The results indicated that test accommodations improve ELLs' test performance by about 0.157 standard deviations—a relatively small but statistically significant increase. Once the potential predictors that may have contributed to the variance of the effect sizes across studies had been accounted for, only English proficiency was found to be significant. Further, the results indicated that ELLs with a low level of English proficiency benefited much more from test accommodations than did those with a high level of English proficiency. Little difference was observed in regard to other factors such as students' ethnicity, students' grade level, or the subject for which they were being examined. Although previous studies have suggested that linguistic simplification may be more effective than other methods, results from this meta-analysis offered no support for that suggestion.     

Science education: A meta-analysis of major questions

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.     

College grades and adult achievement: A research synthesis

The present study used meta-analytic methodology to synthesize research on the relationship between college grades and adult achievement. The data for the meta-analysis came from 108 studies correlating grade average in college to various criteria of adult achievement or success. The average correlation between grade average and a composite success criterion was .18, a small effect. Correlations between grade average and eight other criteria of adult achievement were also small, ranging from .09 to .20. Correlational effects were larger in military settings and for studies conducted prior to 1950. The results of this meta-analysis may be somewhat discouraging to those who place a great deal of importance on the predictive value of grades.     

A meta-analysis of the effects of face-to-face cooperative learning. Do recent studies falsify or verify earlier findings?

One of the major conclusive results of the research on learning in formal learning settings of the past decades is that cooperative learning has shown to evoke clear positive effects on different variables. Therefore this meta-analysis has two principal aims. First, it tries to replicate, based on recent studies, the research about the main effects of cooperative learning on three categories of outcomes: achievement, attitudes and perceptions. The second aim is to address potential moderators of the effect of cooperative learning. In total, 65 articles met the criteria for inclusion: studies from 1995 onwards on cooperative learning in primary, secondary or tertiary education conducted in real-life classrooms. This meta-analysis reveals a positive effect of cooperative learning on achievement and attitudes. In the second part of the analysis, the method of cooperative learning, study domain, age level and culture were investigated as possible moderators for achievement. Results show that the study domain, the age level of the students and the culture in which the study took place are associated with variations in effect size.     

Meta-Analysis and Meta-Synthesis Methodologies: Rigorously Piecing Together Research

For a variety of reasons, education research can be difficult to summarize. Varying contexts, designs, levels of quality, measurement challenges, definition of underlying constructs, and treatments as well as the complexity of research subjects themselves can result in variability. Education research is voluminous and draws on multiple methods including quantitative, as well as, qualitative approaches to answer key research questions. With increased numbers of empirical research in Instructional Design and Technology (IDT), using various synthesis methods can provide a means to more deeply understand trends and patterns in research findings across multiple studies. The purpose of this article is to illustrate structured review or meta-synthesis procedures for qualitative research, as well as, novel meta-analysis procedures for the kinds of multiple treatment designs common to IDT settings. Sample analyses are used to discuss key methodological ideas as a way to introduce researchers to these techniques.     

A Meta-Analysis of School-Age Children's Attitudes Towards Persons with Physical or Intellectual Disabilities

Factors associated with children's attitudes towards persons with physical and intellectual disabilities were examined in a meta-analysis spanning the years 1990 to 2000. A total of 20 studies met the inclusion criteria allowing for 65 comparisons across 2,240 participants. Factors of interest were attitudinal components, type of disability, age and gender of respondents, and role of inclusion. The majority of research findings revealed that children preferred target children without disabilities compared to targets with physical or intellectual disabilities. Three methods for calculating average effect sizes were used: (a) unweighted means, (b) weighted means, and (c) vote counting. It was concluded that biases in attitudes do exist but that summary results need to be interpreted with regard to individual study differences and the methods used to calculate mean effect sizes.     

教育游戏对学生学习效果的影响研究——基于41项实验和准实验的元分析

随着信息技术的发展,教育游戏在教学过程的应用越来越广泛,但学界对其应用效果仍颇具争议。为考察教育游戏对学生学习效果的影响,文章采用元分析法,对教育游戏的实验与准实验研究进行了梳理与分析,发现:相较于传统教学方式,教育游戏对学生的学习效果产生了中等程度的正向影响。之后,文章将学科、知识类型、故事情节、参与方式、研究设计类型作为调节变量,检验了调节变量对研究结果的影响。依据元分析结果,文章针对未来教育游戏应用提出了建议,包括依据不同学科特点设计相应的教育游戏、依据知识类型特征选择合适的教育游戏、增强教育游戏情景设计、增加小组参与的教育游戏模块、注重研究设计的多元化等。     

Synthesising case-study research – ready for the next step?

Within the emerging field of research on education for sustainability (EfS), case studies are an important if not the predominant research approach, although often criticised for its lack of internal and external validity and a tendency to draw conclusions with insufficient rigour. While, basic concerns have been expressed and discussed in an early issue of this journal, main assumption still hold true after more than 10 years of research in the field. Only a few approaches so far have tackled the challenge to provide cross-case comparison and the synthesis of case-study results still remains a research desideratum. In this paper, we argue that developments in the field of qualitative and quantitative meta-analysis in educational science offer a framework, which can be used to overcome that shortcoming. After describing the idea of research synthesis, different types of such a meta-analysis are identified and their potential is discussed for existing case studies in higher EfS. This paper concludes with recommendations for further case-study research in the field.     

The Whole Earth: An EE Perspective

Abstract

Despite the wealth of information which exists concerning environmental behavior, it is not known which variable or variables appear to be most influential in motivating individuals to take responsible environmental action. A meta-analysis of environmental behavior research was undertaken in an attempt to determine this. An exhaustive search of the empirically based environmental behavior research conducted over the past decade yielded a substantial number of studies representative of a broad academic base. The characteristics and findings of these studies served as the data for the meta-analysis. As a result of the meta-analysis, the following variables were found to be associated with responsible environmental behavior: knowledge of issues, knowledge of action strategies, locus of control, attitudes, verbal commitment, and an individual's sense of responsibility. A model of predictors of environmental behavior is proposed.     

近十年傩研究现状考察（1999-2008）

文章据＂中国学术期刊全文数据库CNKI＂（1999-2008）检索出的傩研究论文以及这一时期出版的傩研究专著,对傩文化研究成果地域性、研究内容的各个方面进行了较为系统的总结和归纳,并据之认为傩研究具有地域高度集中、研究各自为政、地方色彩斑斓等方面的时代印迹。     

A meta-analysis of instructional systems applied in science teaching

This article is a report of a meta-analysis on the question: “What are the effects of different instructional systems used in science teaching?” The studies utilized in this meta-analysis were identified by a process that included a systematic screening of all dissertations completed in the field of science education since 1950, an ERIC search of the literature, a systematic screening of selected research journals, and the standard procedure of identifying potentially relevant studies through examination of the bibliographies of the studies reviewed. In all, the 130 studies coded gave rise to 341 effect sizes. The mean effect size produced over all systems was 0.10 with a standard deviation of 0.41, indicating that, on the average, an innovative teaching system in this sample produced one-tenth of a standard deviation better performance than traditional science teaching. Particular kinds of teaching systems, however, produced results that varied from this overall result. Mean effect sizes were also computed by year of publication, form of publication, grade level, and subject matter.     

Fostering scientific reasoning in education – meta-analytic evidence from intervention studies

Scientific reasoning skills are not just for researchers, they are also increasingly relevant for making informed decisions in our everyday lives. How can these skills be facilitated? The current state of research on supporting scientific reasoning includes intervention studies but lacks an integrated analysis of the approaches to foster scientific reasoning in primary through secondary education. This meta-analysis evaluates effect sizes taken from 30 interventions in experimental and quasi-experimental studies and shows a medium mean effect of interventions on scientific reasoning. Interventions successfully facilitate scientific discovery, scientific argumentation, or nature of science in all age groups. Moderator analyses show that interventions set in constructive and interactive learning activities yield positive effects but do not differ substantially. Although the meta-analysis is limited by the number of studies included, we can conclude that scientific reasoning can successfully be facilitated and we show which characteristics are beneficial in educational interventions.