The Effectiveness of a Large-Scale Language and Preliteracy Intervention: The SPELL Randomized Controlled Trial in Denmark

The article presents the results of a randomised control study on the effect of an intervention regarding language skills and early literacy in Danish kindergartens. The intervention is referred to as SPELL (Structured Pre-school Efforts in Language and Literacy).

Research question:

1. To what extent does the SPELL intervention increase children’s language and early literacy compared to everyday kindergarten life in which the intervention is not implemented?
2. To what extent does the professional development of kindergarten teachers, or a home-based training programme, contribute to reinforcing the effects that SPELL has on children’s results?
3. To what extent do risk factors in children moderate the impact of SPELL, especially children’s socioeconomic status and language status?
4. To what extent is children’s exposure to SPELL associated with children’s early language and literacy results?

Measurements before and after the intervention revealed a significant positive effect from all three interventions on early literacy, but not correspondingly for language skills. There was little variation between the different versions of the intervention. Frequency, i.e. how many hours the children were read to, was a significant predictor variable for most of the outcomes.

The article is based on a randomised control study using data from everyday life in Danish kindergartens. Children from 144 kindergartens were given a control variable or one of three planned versions of a 20-week intervention that involved reading picture books: A basic intervention and two further developed versions, based on either the kindergarten teachers’ professional development or a home-based programme for parents or guardians.  

Bleses, D., Højen, A., Dale, P. S., Piasta, S. B., Justice, L. M., Dybdal, L., Markussen-Brown, J., Clausen, M. & Hagish, E. F. (2018). “The Effectiveness of a Large-Scale Language and Preliteracy Intervention: The SPELL Randomized Controlled Trial in Denmark”. Child Development, 89(4):342–363.