Overview of Meta-Analysis, Part 5c (of 7): Primary Meta-Analyses (cont.)

This is the last of three posts in Part 5 of my overview of meta-analysis.  In Part 5a I described six conventional meta-analytic models for effect-size (ES) estimates, and in Part 5b I described estimation and inference for two of those models without covariates.  In this post I’ll extend the methods of Part 5b to two models with covariates and comment on extensions and other variants of these models and procedures, to hint at the wide variety of situations that arise in meta-analysis.  In Parts 6 and 7 of the overview, I’ll address follow-up procedures and ways to report results, respectively.
Read the rest of this entry »

Overview of Meta-Analysis, Part 2 (of 7): Sampling Error

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.)
Read the rest of this entry »

Overview of Meta-Analysis, Part 1 (of 7): Effect Sizes

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

Read the rest of this entry »