Table 14.
Cluster‐robust meta‐regression for grade level for nonacademic effect sizes.
| Effect (n of effect sizes) | Hedges’ g | 95% CI of g | df | p |
|---|---|---|---|---|
| Elementary schoola (39) | 0.26 | (−0.24, 0.76) | 4.93 | 0.235 |
| Preschool (44) | 0.10 | (−0.39, 0.59) | 9.29 | 0.646 |
| Middle school (8) | 0.05 | (−0.72, 0.83) | 2.83 | 0.834 |
Note: N of studies = 18, N of effect sizes = 91, assumed ρ = 0.8, I 2 = 85.60. Cluster‐robust estimates with df < 4.00 should be interpreted with caution(Tanner‐Smith, Tipton, & Polanin, 2016). Wald test for null difference between preschool and middle school grade levels, F(2, 3.39) = 0.10, p = 0.911. Positive effect sizes favor Montessori over traditional education.
Abbreviation: CI, confidence interval.
a
Reference category/intercept.