The purpose of this article is to examine how methodological features such as types of publication, sample sizes, and research designs affect effect sizes in experiments.
Cheung, A., & Slavin, R. E. (2015). How methodological features affect effect sizes in education. Best Evidence Encyclopedia, Johns Hopkins University, Baltimore, MD.
This paper contrasts effect sizes in What Works Clearinghouse and Best Evidence Encyclopedia reading and math reviews to explore the degree to which these measures produce different estimates.
Slavin, R. E., & Madden, N. A. (2008). Understanding bias due to measures inherent to treatments in systematic reviews in education. In annual meeting of the Society for Research on Effective Education, Crystal City, VA.