TABLE 4.
Mean raw scores (SD) for the 12-weeks Early Literacy Intervention group and the Control Group for the primary and secondary outcome measures pre-intervention (t1), immediately post-intervention (t2), and at delayed follow-up (t3, with effect sizes for intervention effects) for the entire sample (N = 189) and the subgroup of children with low oral language (n = 63).
| Entire sample (N = 189) | Subgroups low oral language (n = 63) | ||||||||||
| Reliability |
Intervention group (n = 89) |
Control group (n = 100) |
Effect size |
Intervention group (n = 31) |
Control group (n = 32) |
Effect size | |||||
| M | SD | M | SD | M | SD | M | SD | ||||
| Primary outcomes (Luxembourgish) | |||||||||||
| Rhyme identification | |||||||||||
| • t1 (12) | 0.90 | 5.72 | 4.11 | 7.40 | 3.91 | 3.61 | 3.35 | 4.63 | 3.59 | ||
| • t2 (12) | 0.89 | 8.35 | 3.46 | 8.98 | 3.29 | 0.261 | 6.07 | 3.67 | 6.19 | 3.79 | 0.261 |
| Onset rhyme blending | |||||||||||
| • t1 (12) | 0.91 | 3.70 | 3.73 | 5.00 | 4.10 | 2.32F | 3.27 | 2.84F | 3.41 | ||
| • t2 (12) | 0.91 | 9.19 | 3.48 | 6.99 | 3.89 | 0.971 | 8.20 | 3.38 | 4.38 | 3.97 | 1.302 |
| Onset identification | |||||||||||
| • t1 (12) | 0.79 | 4.26 | 3.07 | 5.30 | 4.25 | 3.10 | 2.47 | 3.03 | 2.52 | ||
| • t2 (12) | 0.83 | 7.45 | 3.52 | 5.99 | 3.34 | 0.791 | 6.17 | 3.74 | 4.13 | 3.04 | 0.791 |
| Onset/phoneme manipulation | |||||||||||
| • t1 (12) | 0.93 | 0.36F | 1.50 | 0.50F | 1.85 | 0.00F | 0.00 | 0.00F | 0.00 | ||
| • t2 (12) | 0.93 | 2.06F | 3.34 | 1.30F | 2.85 | 1.00F | 2.21 | 0.06F | 0.25 | ||
| • t3 (12) | 0.91 | 5.25 | 4.26 | 4.86 | 4.11 | 0.132 | 3.96 | 4.07 | 3.04F | 3.55 | 0.242 |
| Phoneme blending | |||||||||||
| • t1 (12) | 0.92 | 0.65F | 1.50 | 1.86F | 3.25 | 0.29F | 0.90 | 1.06F | 2.46 | ||
| • t2 (12) | 0.90 | 4.64 | 3.58 | 2.77F | 3.29 | 0.902 | 3.20 | 3.23 | 1.34F | 2.47 | 0.922 |
| • t3 (12) | 0.81 | 8.96 | 2.71 | 7.89 | 3.24 | 0.762 | 8.39 | 2.47 | 6.34 | 3.76 | 0.892 |
| Phoneme segmentation | |||||||||||
| • t2 (12) | 0.91 | 3.72 | 3.78 | 1.65F | 2.71 | 0.632 | 2.37F | 3.03 | 0.63F | 1.91 | |
| • t3 (12) | 0.87 | 8.33 | 3.39 | 7.11 | 3.67 | 0.352 | 7.32 | 3.86 | 5.96 | 3.70 | 0.362 |
| Letter-knowledge | |||||||||||
| • t1 (20) | 0.95 | 5.84 | 5.76 | 7.85 | 6.78 | 4.26 | 4.80 | 3.63 | 5.03 | ||
| • t2 (20) | 0.95 | 15.53 | 5.47 | 9.90 | 6.59 | 1.211 | 13.77 | 5.81 | 6.22 | 5.48 | 1.411 |
| • t3 (20) | 0.79 | 19.67F | 0.91 | 19.17C | 1.85 | 19.43C | 1.32 | 18.36C | 2.72 | ||
| Secondary outcomes (German) | |||||||||||
| Onset/phoneme manipulation | |||||||||||
| • t3 (12) | 0.91 | 6.20 | 3.84 | 5.98 | 4.26 | 0.052 | 4.11 | 2.87 | 3.08 | 3.86 | 0.302 |
| Phoneme blending | |||||||||||
| • t3 (12) | 0.85 | 9.83 | 2.44 | 9.12 | 3.09 | 0.252 | 8.96 | 2.83 | 7.12 | 3.63 | 0.572 |
| Phoneme segmentation | |||||||||||
| • t3 (12) | 0.84 | 8.99 | 2.73 | 7.65 | 3.12 | 0.462 | 7.96 | 3.19 | 5.88 | 3.15 | 0.662 |
| Single word reading | |||||||||||
| • t3 (72) | 0.98 | 8.62 | 9.39 | 9.47 | 9.73 | −0.092 | 6.14 | 6.73 | 6.16 | 6.59 | 0.00 |
| Pseudoword reading | |||||||||||
| • t3 (72) | 0.96 | 13.75 | 8.05 | 14.97 | 7.98 | −0.152 | 11.71 | 7.63 | 12.80 | 7.01 | −0.152 |
| Word reading comprehension | |||||||||||
| • t3 (72) | 0.95 | 12.73 | 5.02 | 11.86 | 5.61 | 0.162 | 11.04 | 4.63 | 9.40 | 3.81 | 0.392 |
| Spelling | |||||||||||
| • t3 (40) | 0.93 | 34.25 | 3.24 | 32.37 | 7.50 | 0.322 | 33.14 | 3.88 | 28.60 | 10.66 | 0.572 |
(), maximum possible raw score; C, ceiling effect; F, floor effect. Cohen’s d: 1 = difference in progress between groups divided by pooled initial SD; 2 = difference in means at post-test/follow-up divided by pooled SD at post-test/follow-up (pre-test scores were at floor/not available for same measure so could not be used). A positive effect (Cohen’s d) means that the Intervention Group did better, whereas a negative effect means results in favor of the Control Group. Reliability coefficient = Cronbach’s alpha.