Setting
The study was conducted in a Head Start program in inner-city Los Angeles, California
Study sample
Ninety-six Spanish-speaking English language learners in a Head Start program were randomly assigned, balancing for gender, to one of three conditions: (1) the High/Scope curriculum supplemented with small groups using Literacy Express in English only, (2) the High/Scope curriculum supplemented with small groups using Literacy Express beginning in Spanish and transitioning to English, and (3) the High/Scope curriculum only. Children were assigned to conditions within 10 classrooms. During the course of the year, two children moved, resulting in a sample of 94 children (31 in English-only Literacy Express, 31 in the transitional Literacy Express, 32 in the control group). All children were born in the United States and lived in households in which Spanish was the primary language. Children receiving resource help for speech and language delays were not eligible for the study. The children in the sample were age 54.5 months, on average, and 46% were female.
Intervention Group
The intervention consisted of activities in dialogic reading, phonological awareness, and print knowledge. Dialogic reading activities included scaffolding techniques, such as asking “Wh-” and open-ended questions and using expansions and repetitions to encourage children to talk about the book. Phonological awareness involved word games that used picture puzzles to teach children that words were made of smaller sound units. Print knowledge activities taught children about the alphabet, including recognizing letters and their associated sounds. The intervention was delivered to small groups of four to five children in separate classrooms adjacent to the regular classrooms. The groups met for 20 minutes, four times a week, from mid-November to mid-May and were led by trained bilingual graduate students. In the Spanish-transition condition, instruction was in Spanish for the first eight weeks, followed by three to four weeks of transition. All lessons starting around week 14 were delivered in English. Children in the English-only condition received the full 21 weeks of lessons in English.
Comparison Group
The comparison group received the High/Scope curriculum, which was typically offered in the center.
Outcome descriptions
The primary outcome domains assessed were oral language, print knowledge, and phonological processing, all of which were assessed with standardized measures. Oral language was assessed with the Receptive Vocabulary and Definitional Vocabulary subtests from the Preschool Comprehensive Test of Phonological and Print Processing (Pre-CTOPPP). Print knowledge was assessed with the Print Knowledge subtest from the Pre-CTOPPP. Phonological processing was assessed with the Blending and Elision subtests from the Pre-CTOPPP. Pretesting was done in fall of the preschool year, and posttesting was done in spring of the preschool year. Assessments were administered by trained research staff who were not involved in the delivery of the intervention and were blind to the children’s treatment status. Assessments were conducted with all children
in English and Spanish; only the English assessments are used in the rating of the intervention. Outcomes for the Spanish assessments are included in Appendix 4.1–A4.3, A4.5, A4.7, and A4.9. For a more detailed description of the outcome measures, see Appendices A2.1–A2.5.
Support for implementation
Four bilingual graduate students were taught to deliver the intervention by one of the study’s authors, who also supervised the intervention. No other information on training is provided.