A search of published and unpublished articles focused on those that met the following criteria:
- The studies involved primary school-age children identified as having English as an additional language.
- Schools or classrooms using each programme had to be compared to randomly assigned or
well-matched control groups.
- Study duration had to be at least 12 weeks.
- The language of instruction was the same in experimental and control classes.
- Outcome measures had to be reliable and valid assessments of the reading skills being taught in all classes.
- The review placed particular emphasis on studies in which schools, teachers, or pupils were assigned at random to experimental or control groups.
The full report
- For the full report, which this review summarises , see Cheung, A., and Slavin, R. E. (2005) Bilingual Research Journal, volume 29, no. 2, pp. 241-267.