It is well established that children’s language knowledge at the age of five is strongly related to later reading achievement and that children identified with language impairments before starting compulsory school are at higher risk of reading difficulties (Catts, Fey, Tomblin, & Zhang, 2002; Hulme & Snowling, 2009). Although language and reading skills are important for academic achievement, few longitudinal studies have explored the relationship between children’s language skills at the start of school and later academic achievement. In small communities, such as Iceland, it is relatively easy to track participants making them ideal for longitudinal studies.

Language knowledge and reading ability are related; reading improves language knowledge, and vocabulary. Through reading, children learn words and become familiar with complex sentences. The Simple view of reading (Gough & Tunmer, 1986) captures the role of different skills in reading development. Phonological skills are fundamental for the decoding of alphabetic letters into sounds and words (Hulme & Snowling, 2009) but reading comprehension is composed of both language comprehension and decoding skills.

Phonological awareness is the understanding of the sound structure of spoken words. It develops to some extent before the child learns how to read, but improves when the child masters the skills of reading. It seems that that phonological awareness has a causal relationship with reading achievement during the first years of schooling (Catts, et al., 2002; Hulme & Snowling, 2009; Peterson & Pennington, 2012).

Before the age of five there are great individual differences in the speed at which children acquire language, in terms of their vocabulary, their grammar and their understanding of sentences (Fenson et al., 1994). Many children who are identified having language problems during early preschool years may have resolved those problems by the time they entered compulsory school (Hayiou-Thomas, Dale & Plomin., 2014).

Early intervention can have a major impact on a child’s later development and academic achievement (Torgesen, 2002; Vellutino, Scanlon, Small, & Fanuele, 2006). Environmental factors can influence vocabulary development, and it is possible to improve phonological awareness via instruction and intervention. It is therefore important to investigate risk factors early in life and to provide appropriate assistance to facilitate successful schooling and academic performance (Hulme & Snowling, 2009).

Preschools are part of the educational system in Iceland like in many other European countries and almost all children attend. Preschool teachers are in daily contact with parents who commonly seek feedback regarding their child’s development. It is therefore important that preschool teachers have the knowledge and skills to identify and to respond effectively to difficulties in language development.

The phonological awareness test HLJÓM-2 was developed to identify, before formal reading instruction starts, those children who are at risk of reading difficulties (Ingibjörg Símonardóttir, Jóhanna Einarsdóttir, & Amalía Björnsdóttir, 2002). The development of HLJÓM-2 was based on six years of investigations.

The children who were involved in the HLJÓM-2 development participate in this study (now 18 and 19 years of age). Their vocabulary and comprehension was investigated during the developmental phase of the HLJÓM-2 with the Icelandic version of the TOLD-2P language test (Ingibjörg Símonardóttir, Einar Guðmundsson, Sigurgrímur Skúlason, & Sigríður Pétursdóttir, 1995; Newcomer & Hammill, 1988).

The purpose of this study was to investigate whether language assessment at five years of age could predict results on national tests in Icelandic and Mathematics in Grades 4, 7 and 10.

The following research questions were posed:

Do language measurements before the start of compulsory school correlate with academic performance in Icelandic and Mathematics throughout the 10 years of schooling?

Do different aspects of language knowledge demonstrate different patterns of correlation with age?

Amalía Björnsdóttir, Ingibjörg Símonardóttir, & Jóhanna Einarsdóttir. (2003). Þróun HLJÓM-2 og tengsl þess við lestrarfærni og ýmsa félagslega þætti. [The development of HLJÓM-2 and the relationship of the scores with reading ability and some social factors]. Uppeldi og menntun, 12, 9–30. Catts, H. W., Fey, M. E., Tomblin, J. B., & Zhang, X. (2002). A longitudinal investigation of reading outcomes in children with language impairments. Journal of Speech, Language, and Hearing Research, 45, 1142–1157. Fenson, L., Dale, P. S., Reznick, J. S., Bates, E., Thal, E. J., . . . Stiles, J. (1994). Monographs of the Society for Research in Child Development, Vol. 59, No. 5, Variability in early communicative development. Monographs of the Society for Research in Child Development i+iii-v+1-185. doi: 10.2307/1166093 Gough, P. B., & Tunmer, W. E. (1986). Decoding, reading and reading disability. Remedial and Special Education, 7, 6–10. Hayiou-Thomas, M.E., Dale, P.S., & Plomin, R., (2014). Language impairment from 4 to 12 years: Prediction and etiology. Journal of Speech, Language, and Hearing Research, 57, 850–864. doi:10.1044/2013_JSLHR-L-12-0240. Hulme, C., & Snowling, M. J. (2009). Developmental disorders of language learning and cognition. West Sussex: Wiley-Blackwell. Ingibjörg Símonardóttir, Einar Guðmundsson, Sigurgrímur Skúlason, & Sigríður Pétursdóttir. (1995). TOLD-2P. Málþroskapróf. Íslensk staðfærsla. [TOLD-2P: Test of Language Development. Icelandic version]. Reykjavík: Rannsóknastofnun uppeldis- og menntamála. Ingibjörg Símonardóttir, Jóhanna Einarsdóttir, & Amalía Björnsdóttir. (2002). HLJÓM-2 handbók.[ HLJÓM-2 handbook]. Reykjavík: Authors. Newcomer, P. L., & Hammill, D. (1988). TOLD-2P: Test of Language Development Primary (2nd ed.) Austin, TX: Pro-Ed. Peterson, R. L., & Pennington, B. F. (2012). Developmental dyslexia. The Lancet, 379, 1997–2007. Torgesen, J. K. (2002). The prevention of reading difficulties. Journal of School Psychology, 40, 7–26. Vellutino, F. R., Scanlon, D. M., Small, S., & Fanuele, D. F. (2006). Response to intervention as a vehicle for distinguishing between children with and without reading disabilities: Evidence for the role of kindergarten and first-grade interventions. Journal of Learning Disabilities, 39, 157–169.