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### Table B-10Mean efficiency for the ES indexes as a function of the correlation (r) between pretest and post-test

r | d_{hb} | d_{hw} | d_{b} | d_{g} | d_{s1} | d_{s2} | d_{s3} |
---|---|---|---|---|---|---|---|

.00 | 0.0011 | 0.0003 | 0.0011 | 0.0006 | 0.0006 | 0.0006 | 0.0006 |

.25 | 0.0011 | 0.0003 | 0.0011 | 0.0007 | 0.0006 | 0.0006 | 0.0006 |

.50 | 0.0011 | 0.0004 | 0.0011 | 0.0011 | 0.0007 | 0.0007 | 0.0006 |

.75 | 0.0011 | 0.0005 | 0.0011 | 0.0028 | 0.0009 | 0.0009 | 0.0007 |

*Note.*See Tables 1 and 2 in the main report for definitions of each ES index.*d*_{b}=Becker’s standardized mean difference;*d*_{g}=Gibbons’s standardized mean difference.*d*_{hb}=Hedges’s standardized mean difference using the between-studies degrees of freedom.*d*_{hw}=Huedo-Medina and Johnson’s standardized mean difference using the within-study degrees of freedom.*d*_{s1}=Standardized mean difference proposed by Shadish (See Table 2, No. 10).*d*_{s2}=Standardized mean difference proposed by Shadish using the standard deviation from ANOVA results (See Table 2, No. 11).*d*_{s3}=Standardized mean difference proposed by Shadish using the standard deviation from ANCOVA results (See Table 2, No. 12).

Meta-Analytic Statistical Inferences for Continuous Measure Outcomes as a Function of Effect Size Metric and Other Assumptions [Internet].

Johnson BT, Huedo-Medina TB.

Rockville (MD): Agency for Healthcare Research and Quality (US); 2013 Apr.