A primer on the understanding of meta-analysis

The purpose of the present paper is to provide a primer on the understanding of meta-analysis. After presenting the rationale behind meta-analysis, the present paper defines statistical artifacts of sampling error and measurement. Examples show that statistical artifacts influence the correlation coefficient. The paper also explains the notions of confidence intervals and credibility intervals and how correlations corrected for sampling error and measurement error are calculated. The paper concludes by explaining the notion of second-order sampling error and moderator meta-analysis.