Harris, M. J., & Rosenthal, R. (1985). Mediation of interpersonal expectancy effects: 31 meta-analyses. Psychological bulletin, 97(3), 363-386.
Reviews 135 studies on mediation and classifies results into 31 behavior categories (e.g., praise, climate, asks questions). Separate meta-analyses for each mediating variable were conducted. Results were also analyzed separately for studies that examined the relation between expectations and emitted behaviors and between mediating behaviors and outcome measures. Additional analyses focused on the influence of internal validity and type of publication on effect sizes. Meta-analyses ...