Focusing on psychotherapy research, illustrates methods for studying mediator and moderator variables in meta-analysis, discusses their advantages and disadvantages, and shows how inclusion of these variables can change interpretation of meta-analytic results. Notes that therapeutic orientation may make significant difference to outcome but only…

Introduces statistical and procedural methods of meta-analysis, and explains how to interpret the findings of meta-analytic studies currently appearing throughout the social science literature. Includes overview of meta-analysis and discussion of seven steps used in conducting a meta-analysis. (Author/NB)

Tells how to conduct a meta-analysis study, and refers readers to information about refinements of the techniques. A simple meta-analysis is presented. Describes three fundamental stages to conducting a meta-analysis: (1) literature review; (2) calculation of effect sizes; and (3) analysis of data. (Author/NB)

Demonstrates that magnitude-of-effects (ME) estimates vary in susceptibility to sample-size bias depending on whether they are directional or nondirectional estimates. Also demonstrates that study characteristics that influence size of ME estimates can be explicitly taken into account when comparing studies. Emphasizes need to consider study…

The use of measures of magnitude of effect has been advocated as a way to go beyond statistical tests of significance and to identify effects of a practical size. They have been used in meta-analysis to combine results of different studies. Describes problems associated with measures of magnitude of effect (particularly study size) and…