Effects of a digitized phonics intervention in a Swedish context: intervention and booster outcomes for second‑grade students. KILA (Kompletterande intensiv lästräning i avkodning; Supplementary intensive reading instruction in decoding)
Risk for reading difficulties
The intervention focuses on phonics to improve reading skills in Swedish students at risk of reading difficulties. The intervention is a digital adaptation of the program described in Lindström Sandahl et al. (2023). The program consists of 36 lessons, delivered 4 times a week for 9 weeks, and provides structured instruction in grapheme–phoneme correspondences to support decoding and spelling of simple words. Students repeatedly practice phoneme blending, segmentation, word reading, and sentence reading to strengthen phonological awareness, decoding, and spelling skills and to develop reading fluency. The intervention is delivered one-to-one (one student and one teacher) via the web portal of the non-profit organisation LegiLexi. The program is complementary as students also take part of regular classroom reading instruction. A total of 200 students will be randomly assigned to the intervention group and an equal number to the control group. The control group will receive regular instruction, including special education support in accordance with the Swedish national curriculum. Participants in the control group will be offered the opportunity to complete the program in the following semester (spring 2027) as part of a wait-list control design. After completing the post-tests, half of the students in the intervention group (N = 100) will be randomly assigned to participate in a booster component consisting of 12 selected lessons from the intervention program delivered over three weeks (boost intervention group). The remaining half of the intervention group will serve as a comparison group for the effects of this additional reinforcement (boost control group, N = 100) and will receive teaching as usual. The booster phase will be implemented three months after the completion of the original 36 intervention lessons. The LegiLexi Foundation assesses reading, spelling, and language skills three times per year during specified testing windows (autumn, winter, and spring
1. Enrolment in Grade 2 2. Scores below the 10th percentile on a composite measure based on screening tests of word decoding and word recognition from the LegiLexi battery administered during the spring term of Grade 1
1. No children meeting the inclusion criteria will be excluded from participation 2. Children who do not complete the intervention or the post-test assessments will be excluded from the analyses