Table 2.
First author (year) | NC | NE | Age | Sample | Intervention | Effect Sizes | |||||
---|---|---|---|---|---|---|---|---|---|---|---|
Category | Stat | Source | Type | Effect | Size | ||||||
Diamond (2007) | 62 | 85 | 5 | Low SES | Self-regulation, play, memory, attention, and listening skills | IG post | — | — | N | ↑ inhibitory control | — |
IG post | — | — | N | ↑ EF | — | ||||||
—b | r | R | F | EF correlation with academic scores | 0.41a | ||||||
Raver (2009) | 218 | 231 | 3–5 | Low SES | Teacher training: clear rules, monitoring, and positive reinforcement | IG p-p | d | R | F | ↓ internalizing | 0.76a |
IG p-p | d | R | F | ↓ externalizing | 0.59a | ||||||
Tominey (2011) | 37 | 28 | 4–5 | ½ low SES | Playgroup games: attention, memory, and inhibitory control | IG post | d | C | N | ↑ inhibitory control | 0.69c |
IG p-p | d | C | F | ↑ reading | 0.44 | ||||||
Bruce (2009) | 24d | 10 | 5–7 | Foster care | Parent training and therapeutic playgroup | IG post | ηp2 | R | F | ↑ feedback-related ERP amplitude | 0.25 |
Note. Age is given in years. See Supplementary Material for definitions and procedures for determining the effect sizes (Stat) based on the parameters given in the original studies.
NC = sample size of the control group; NE = sample size of the experimental/training group; IG p-p = independent groups, pre-post; IG post = independent groups, post; Stat = the effect size statistic given; d = Cohen’s d; ηP2 = Partial Eta-squared; r = Pearson’s product moment correlation; C = effect size calculated; R = effect size value as reported in the original study; N = near (improvement on trained tasks or nontrained, structurally similar tasks); F = far (improvement on structurally dissimilar tasks).
Average effect size calculated from multiple dependent variables measuring the same construct.
Measure not administered to control group.
Effect found in subset with low initial executive function scores.
Multiple control groups used, combined N given.