什么是Meta分析-牛津大学

→ Systematic synthesis of various studies on a particular
research question Do boys or girls have higher self-concepts?
→ Collect all studies relevant to a topic
Compared to traditional literature reviews:
(1) there is a definite methodology employed in the research analysis; and (2) the results of the included studies are quantified to a standard metric thus allowing for statistical techniques for further analysis.
There exists a critical mass of comparable studies designed to address a common research question. Data are presented in a form that allows the meta-analyst to compute an effect size for each study. Characteristics of each study are described in sufficient detail to allow meta-analysts to compare characteristics of different studies and to judge the quality of each study.
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The essence of good science is replicable and generalisable results. Do we get the same answer to important research questions when we run the study again? The primary aims of meta-analysis is to test the generalisability of results across a set of studies designed to answer the same research question. Are the results consistent? If not, what are the differences in the studies that explain the lack of consistency?
and compared; tests moderator variables Do gender differences vary with age, setting, ethnicity, self-concept, domain, etc.
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Coding: the process of extracting the information from the literature included in the meta-analysis. Involves noting the characteristics of the studies in relation to a priori variables of interest (qualitative) Effect size: the numerical outcome to be analysed in a meta-analysis; a summary statistic of the data in each study included in the meta-analysis (quantitative) Summarise effect sizes: central tendency, variability, relations to study characteristics (quantitative) 4
Therefore less biased and more replicable
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Increased power: increases the chance of detecting a true treatment effect Improved precision: with more information than a single study, the treatment effect estimate is improved When study-to-study variation in results (which is typical) can evaluate differences in relation to study characteristics. Can delve into research questions not explored by the individual studies Easy to interpret summary statistics (useful if communicating findings to a non-academic audience)
→ “Content analysis”
code characteristics of the study; age, setting, ethnicity, self-concept domain (math, physical, social), etc.
→ Effect sizes with similar features are grouped together
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Meta-analysis is an increasingly popular tool for summarising research findings; literature review method of choice in many disciplines Widely-cited. If there is a good metaanalysis relevant to your study, you have to cite it Relied upon by policymakers Important that we understand the method, whether we conduct or consume meta-analytic research Should be one of the topics covered in8 all introductory research methodology
NCRM Research Methods Festival University of Oxford
Dept of Education, University of Oxford
RMF – Meta-analysis workshop (Marsh, O’Mara, Malmberg)
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Traditionally, social science researchers collect and analyse their own data (referred to as primary data). Secondary data analysis is based on data collected by someone else (or, perhaps, re-analysis of your own published data). There are at least four logical perspectives to this issue: 1. Meta-analysis -- systematic, quantitative review of published research in a particular field, the focus of this presentation. 2. Systematic review -- systematic, qualitative review of published research in a particular field 3. Secondary Data Analyses -- using large (typically public) databases 4. Re-analyses of published studies -- often in ways 2 critical of the original study.
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The number of metaanalyses is increasing at a rapid rate.
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Psychology: Citations
Psychology: Art& Keith, B. (1991). Parental divorce and the well-being of children: A meta-analysis . Psychological Bulletin, 110, 26-46. Times Cited: 471 Linn, M. C., & Petersen, A. C. (1985). Emergence and characterization of sex differences in spatial ability: A metaanalysis . Child Development, 56, 1479-1498. Times Cited: 570 Johnson, D. W., & et al (1981). Effects of cooperative, competitive, and individualistic goal structures on achievement: A meta-analysis . Psychological Bulletin, 89, 47-62. Times Cited: 426 Tett, R. P., Jackson, D. N., & Rothstein, M. (1991). Personality measures as predictors of job performance: A meta-analytic review . Personnel Psychology, 44, 703-742 Times Cited: 387 Hyde, J. S., & Linn, M. C. (1988). Gender differences in verbal ability: A meta-analysis . Psychological Bulletin, 104, 53-69. Times Cited: 316 13 Iaffaldano, M. T., & Muchinsky, P. M. (1985). Job satisfaction and job performance: A meta-analysis . Psychological