| Author/s (year) | Topic Research questions | Research Design | Statistical analysis |
| | Will an improvement in linguistic and meta-linguistic skills in English as a FL lead to an improvement in Hebrew as the L1? Which type of readers (with dyslexia, poor, typical) will benefit more from the English intervention program? | Intervention program by testing skills included phonology, morphology, syntax, semantics, orthography, decoding, reading fluency, reading comprehension, dictation, and spelling. | Linear regression analysis was performed to test the existence of transfer from skills in English to skills in Hebrew |
| | Can linguistic and metalinguistic skills be transferred from foreign language (second language) to the first language (the mother tongue)? | Intervention program that tested by experimental process to test the linguistic skills | t-test |
| | Do children with higher initial skills in either L1 or L2 would benefit more from an intervention designed to promote skill development in the other language than would children with lower initial L1 or L2 skills (for all skills). for those skills that are specific-language independent (i.e., PA) | Intervention program that test the Vocabulary, Phonological awareness and Print knowledge | Regression analyses and interactions |
| | Is there any effect of L2 on L1? Do L2 reading skills influence L1 reading skills? Do L2 learners develop their L1 reading skills by having L2 reading courses? | Intervention program | parametric data analysis t-test, and Levene’s test. |
| | Is there a transfer of linguistic and meta-linguistic skills from L3 to L1 and to L2? Is there cognitive retroactive transfer (CRT) of skills? | Intervention program | Multivariate Analysis of Variance (One Way MANOVA) |
| | Whether an improvement in English as a second language causes an improvement among poor readers in Hebrew as the first language? | Intervention program | A nonparametric test (Wilcoxon test) for dependent samples. |
| | Will there be an improvement in L2 decoding after the intervention in L2? Will there be an improvement in L1 decoding after the intervention in L2? Will there be an improvement in L2 spelling after the intervention in L2? Will there be an improvement in L1 spelling after the intervention in L2? | Intervention program | A nonparametric test (Wilcoxon test) for dependent samples. |
| | Do literacy skills in English and Kiswahili have bidirectional relations for Grade 1 and 2 children in Kenya? If they do, does the nature of the bidirectional relations differ as a function of instructional approaches and environments (i.e., intervention condition compared with control)? | Intervention program | cross-lagged path models with auto-regressors and correlations |