Table 2.
Average Weighted Effect Sizes and Relevant Statistics for Multicomponential Studies
| Type of instruction | k | n | Average weighted effect size |
95% CI |
τ2 | Homogeneity of effect sizes |
File drawer statistic |
||
|---|---|---|---|---|---|---|---|---|---|
| Lower bound | Upper bound | Q | p | ||||||
| Letter name knowledge outcomes | |||||||||
| Full sample | 27 | 2631 | 0.43 | 0.22 | 0.64 | 0.24 | 159.21 | < .001 | 549 |
| Studies providing LN instruction | |||||||||
| With PA | 1 | 33 | 1.00 | 0.27 | 1.72 | 1 | |||
| Without PA | 2 | 72 | 0.20 | −0.24 | 0.65 | −0.02 | 0.86 | .353 | |
| Studies providing LS instruction | |||||||||
| With PA | 6 | 461 | 0.18 | −0.01 | 0.36 | 0.00 | 4.24 | .515 | |
| Studies providing both LN and LS instruction | |||||||||
| With PA | 17 | 2041 | 0.58 | 0.31 | 0.86 | 0.27 | 125.19 | < .001 | 451 |
| Without PA | 1 | 24 | −1.85 | −2.82 | −0.88 | 3 | |||
| Letter sound knowledge outcomes | |||||||||
| Full sample | 36 | 3616 | 0.65 | 0.44 | 0.86 | 0.32 | 270.92 | < .001 | 2176 |
| Studies providing LN instruction | |||||||||
| Without PA | 3 | 48 | 0.82 | 0.22 | 1.41 | 0.00 | 0.76 | .684 | 3 |
| Studies providing LS instruction | |||||||||
| With PA | 17 | 1863 | 0.85 | 0.63 | 1.08 | 0.15 | 69.36 | < .001 | 1048 |
| Studies providing both LN and LS instruction | |||||||||
| With PA | 15 | 1681 | 0.48 | 0.17 | 0.79 | 0.29 | 106.55 | < .001 | 167 |
| Without PA | 1 | 24 | −1.31 | −2.20 | −0.42 | 1 | |||
| Letter writing outcomes | |||||||||
| Full sample | 6 | 741 | 0.59 | 0.31 | 0.86 | 0.07 | 14.70 | .012 | 76 |
| Studies providing LS instruction | |||||||||
| With PA | 4 | 601 | 0.60 | 0.25 | 0.94 | 0.09 | 11.30 | .010 | 41 |
| Studies providing both LN and LS instruction | |||||||||
| With PA | 2 | 140 | 0.58 | −0.05 | 1.21 | 0.15 | 3.40 | .065 | |
| Letter name fluency outcomes | |||||||||
| Full sample | 17 | 2016 | −0.02 | −0.25 | 0.21 | 0.17 | 82.89 | < .001 | |
| Studies providing LN instruction | |||||||||
| With PA | 1 | 43 | −0.61 | −1.23 | 0.00 | ||||
| Without PA | 1 | 139 | 0.16 | −0.20 | 0.51 | ||||
| Studies providing LS instruction | |||||||||
| With PA | 7 | 1385 | 0.07 | −0.09 | 0.23 | 0.02 | 10.23 | .115 | |
| Without PA | 1 | 24 | −0.32 | −1.13 | 0.48 | ||||
| Studies providing both LN and LS instruction | |||||||||
| With PA | 7 | 425 | −0.04 | −0.76 | 0.69 | 0.84 | 65.05 | < .001 | |
| Letter sound fluency outcomes | |||||||||
| Full sample | 4 | 428 | 0.58 | 0.38 | 0.79 | 0.00 | 1.21 | .752 | 24 |
| Studies providing LS instruction | |||||||||
| With PA | 3 | 404 | 0.60 | 0.48 | 0.72 | −0.02 | 0.65 | .723 | 22 |
| Without PA | 1 | 24 | 0.29 | −0.52 | 1.09 | ||||
Note, k = number of independent contrasts/studies; n = total number of children; CI = confidence interval; τ2 = between-study variability; LN = letter name; PA = phonological awareness; LS = letter sound.