**Posted:** March 19, 2012 | **Author:** A. R. Hafdahl | **Filed under:** Overview of Meta-Analysis | **Tags:** coding, effect size, inclusion/exclusion, individual participant data, meta-analysis, missing data, moderator, primary-study quality |
In Part 2 of this seven-part overview, I described obtaining the sample size(s) or conditional variance (CV) associated with an effect-size (ES) estimate to quantify this estimate’s sampling error or (im)precision. Here in Part 3 I’ll address **coding features linked to ESs**. Whereas this overview’s first three parts focus on collecting data used in a research synthesis, its subsequent four parts will address meta-analyzing these data and presenting results. (Part 1 lists the topics for all seven parts.)

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**Posted:** March 11, 2012 | **Author:** A. R. Hafdahl | **Filed under:** Overview of Meta-Analysis | **Tags:** binary outcome, conditional variance, correlation, dependence, effect size, heterogeneity, meta-analysis, missing data, multivariate effect size, primary-study design, sample size, standardized mean difference |
In Part 1 of this seven-part overview of meta-analysis, I introduced Conn, Hafdahl, Cooper, Brown, and Lusk’s (2009) quantitative review of workplace exercise interventions and discussed extracting effect-size (ES) estimates. Building on that material, in this second part I’ll address **obtaining info about an ES’s sampling error**, which plays a critical role in most modern meta-analytic methods. (Part 1 of this overview lists topics in the subsequent five posts.)

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**Posted:** February 27, 2012 | **Author:** A. R. Hafdahl | **Filed under:** Overview of Meta-Analysis | **Tags:** binary outcome, correlation, dependence, effect size, meta-analysis, missing data, multivariate effect size, standardized mean difference, substantive application |
This post is the first in a seven-part overview of common meta-analytic tasks. In this first part I’ll introduce a real-world **substantive application of meta-analysis** and address **estimating effect sizes** (ESs). Subsequent parts will focus on the following topics:

- Part 2: obtaining information about ES sampling error
- Part 3: collecting features of ESs
- Part 4: exploring data
- Part 5: fitting meta-analytic models to ESs (subparts 5a, 5b, and 5c)
- Part 6: checking for potential problems
- Part 7: expressing results informatively

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**Posted:** February 15, 2012 | **Author:** A. R. Hafdahl | **Filed under:** Uncategorized | **Tags:** bibliography, book, consulting, meta-analysis, methodology, research synthesis, software |
In Part 1 of this two-part post I mentioned a few major organizations that provide resources for research synthesis and described numerous training opportunities. Here, in Part 2, I’ll discuss the plethora of **publications** on relevant methodology, options for **software**, and potential benefits of involving **collaborators** (e.g., colleagues, consultants).

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**Posted:** February 11, 2012 | **Author:** A. R. Hafdahl | **Filed under:** Uncategorized | **Tags:** Bayesian analysis, Campbell Collaboration, Cochrane Collaboration, mixed model, research synthesis, statistics, training |
In this blog I’ll cover diverse topics in meta-analytic methodology. It isn’t, however, intended as a one-stop resource. Whether you (plan to) produce or consume research syntheses, teach would-be meta-analysts, or follow this topic for other reasons, you’ll likely benefit from other sources of information and support. This is especially true if you’re interested in areas of the research synthesis landscape beyond the realm of meta-analytic techniques.

In this two-part post I’ll try to drive visitors away from this blog. 😮 Specifically, I’ll describe several (related) types of resources to consider: **organizations** and **training** here in Part 1, and **methodological publications**, **software**, and **collaborators** later in Part 2.

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**Posted:** February 1, 2012 | **Author:** A. R. Hafdahl | **Filed under:** Uncategorized | **Tags:** consulting, effect size, math notation, meta-analysis, methodology, research synthesis |
Welcome to my first ever blog. In this inaugural post I’ll comment on topics I anticipate covering, a few challenges of blogging about statistics, and my primary reasons for undertaking this endeavor.

## Anticipated Topics

This blog is about meta-analysis methodology and related topics. Let’s break that down:

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