How are meta-analysis results displayed?
The typical graphic displaying meta-analysis data is a Forest plot, in which the point estimate for the risk ratio is represented by a square or circle and the confidence interval for each study is represented by a horizontal line.
What are moderators in a meta-analysis?
Meta-analysis Overview. A moderator is a third variable that conditions the relations between 2 others. Because effect sizes are the relations between 2 variables, any variable that predicts the effect sizes is a moderator.
How many studies should be in a meta-analysis?
Two studies
Two studies is a sufficient number to perform a meta-analysis, provided that those two studies can be meaningfully pooled and provided their results are sufficiently ‘similar’.
How does meta-regression work?
Meta-regression is an extension to subgroup analyses that allows the effect of continuous, as well as categorical, characteristics to be investigated, and in principle allows the effects of multiple factors to be investigated simultaneously (although this is rarely possible due to inadequate numbers of studies) ( …
How are Moderator analyses used in a meta-analysis?
Moderator analyses in meta-analysis • We often want to test our hypotheses about whether variation among studies in effect size is associated with differences in study methods or participants • We have these ideas a priori, incorporating these characteristics of studies into our coding forms
Which is an example of a meta-analysis?
• For example, we will look at a meta-analysis where we compare the mean effect size for studies published in three different sources: journals, dissertations, and unpublished studies 3 Campbell Collaboration Colloquium – May 2012 www.campbellcollaboration.org
When do you use a categorical moderator model?
Categorical moderators • When the moderator variable is categorical, we can estimate models analogous to ANOVA • Typically, we are interested in comparing the group mean effect sizes for 2 or more groups
Who are the authors of categorical models and meta regression?
Applied topics: Moderator analyses: Categorical models and Meta-regression Ryan Williams Former Managing Editor, Methods Coordinating Group Assistant Professor, Counseling, Educational Psychology, and Research, University of Memphis, USA Campbell Collaboration Colloquium – May 2012 www.campbellcollaboration.org