The purpose of this study was to investigate the relationship between language knowledge at 5 years of age and later academic achievement throughout compulsory school in Iceland.


Between 1997 and 1998, 267 Icelandic preschool children aged from 5;4 (years;months) to 5;10 were tested with the HLJÓM-2 (an Icelandic test of phonological awareness; Símonardóttir, Einarsdóttir, & Björnsdóttir, 2002) and the Icelandic version of the Test of Language Development—Primary: Second Edition (TOLD-2P; oral comprehension tasks; Símonardóttir, Guðmundsson, Skúlason, & Pétursdóttir, 1995). In 2011 these individuals, now aged 18–19 years, were contacted again. Of the original 267 participants, 221 (83%) gave permission to link their results from the preschool language assessments with their performance on national tests in 4th, 7th, and 10th grades.


The results showed strong correlation between phonological awareness (as measured by the HLJÓM-2) and academic achievement (Icelandic and mathematics) in 4th, 7th, and 10th grades. There was also a significant but lower correlation with oral comprehension skills, as measured with the TOLD-2P. Regression analysis showed that the preschool oral-language assessments in phonological awareness and oral comprehension explained between 35% and 43% of variability in scores on national tests in Icelandic and between 20% and 39% of variability in scores in mathematics.


Preschool language knowledge is a reliable predictor of later academic achievement.


  • Bishop, D. V. M., & Adams, C. (1990). A prospective study of the relationship between specific language impairment, phonological disorders and reading retardation.The Journal of Child Psychology and Psychiatry, 31, 1027–1050.
  • Björnsdóttir, A., Símonardóttir, I., & Einarsdóttir, J. (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.
  • Cabell, S. Q., Justice, L. M., Piasta, S. B., Curenton, S. M., Wiggins, A., Turnbull, K. P., & Petscher, Y. (2011). The impact of teacher responsivity education on preschoolers' language and literacy skills.American Journal of Speech-Language Pathology, 20, 315–330.
  • K. Cain, & J. Oakhill (Eds.). (2007). Children's comprehension problems in oral and written language: A cognitive perspective. New York, NY: Guilford Press.
  • Case-Smith, J., & Holland, T. (2009). Making decisions about service delivery in early childhood programs.Language, Speech, and Hearing Services in Schools, 40, 416–423.
  • 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.
  • Catts, H. W., Fey, M. E., Weismer, S. E., & Bridges, M. S. (2014). The relationship between language and reading abilities.In J. B. Tomblin & M. A. Nippold (Eds.), Understanding individual differences in language development across the school years (pp. 144–165). New York, NY: Psychology Press.
  • Catts, H. W., Fey, M. E., Zhang, X., & Tomblin, J. B. (1999). Language basis of reading and reading disabilities: Evidence from a longitudinal investigation.Scientific Studies of Reading, 3, 331–361.
  • Chen, F., & Chalhoub-Deville, M. (2015). Differential and long-term language impact on math.Language Testing. Advance online publication. doi:10.1177/0265532215594641
  • Cirrin, F. M., & Gillam, R. B. (2008). Language intervention practices for school-age children with spoken language disorders: A systematic review.Language, Speech, and Hearing Services in Schools, 39, S110–S137.
  • Conti-Ramsden, G., St Clair, M. C., Pickles, A., & Durkin, K. (2012). Developmental trajectories of verbal and nonverbal skills in individuals with a history of specific language impairment: From childhood to adolescence.Journal of Speech, Language, and Hearing Research, 55, 1716–1735.
  • Dale, P. S., Price, T. S., Bishop, D. V. M., & Plomin, R. (2003). Outcomes of early language delay: I. Predicting persistent and transient language difficulties at 3 and 4 years.Journal of Speech, Language, and Hearing Research, 46, 544–560.
  • Einarsdóttir, J., Björnsdóttir, A., & Símonardóttir, I. (2004). Málþroskamælingar í leikskóla og forspárgildi þeirra um námsgengi í grunnskóla [Language assessment in preschool and its predictive value on academic achievement in compulsory school].Uppeldi og menntun, 13(1), 67–90.
  • Fenson, L., Dale, P. S., Reznick, J. S., Bates, E., Thal, E. J., Pethick, S. J., … Stiles, J. (1994). Variability in early communicative development [Monograph].Monographs of the Society for Research in Child Development, 59(5, Serial No. 242), 1–185.
  • Gough, P. B., & Tunmer, W. E. (1986). Decoding, reading, and reading disability.Remedial and Special Education, 7(1), 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.
  • Hayiou-Thomas, M. E., Harlaar, N., Dale, P. S., & Plomin, R. (2010). Preschool speech, language skills, and reading at 7, 9, and 10 years: Etiology of the relationship.Journal of Speech, Language, and Hearing Research, 53, 311–332.
  • Hindson, B., Byrne, B., Fielding-Barnsley, R., Newman, C., Hine, D. W., & Shankweiler, D. (2005). Assessment and early instruction of preschool children at risk for reading disability.Journal of Educational Psychology, 97, 687–704.
  • Howell, D. C. (2010). Statistical methods for psychology (7th ed.). Belmont, CA: Wadsworth.
  • Hulme, C., & Snowling, M. J. (2009). Developmental disorders of language learning and cognition. West Sussex, United Kingdom: Wiley-Blackwell.
  • Johnson, C. J., Beitchman, J. H., & Brownlie, E. B. (2010). Twenty-year follow-up of children with and without speech-language impairments: Family, educational, occupational, and quality of life outcomes.American Journal of Speech-Language Pathology, 19, 51–65.
  • Jordan, J. A., Wylie, J., & Mulhern, G. (2015). Mathematics and reading difficulty subtypes: Minor phonological influences on mathematics for 5–7-years-old.Frontiers in Psychology, 6, 221.
  • Justice, L. M., Kaderavek, J. N., Fan, X., Sofka, A., & Hunt, A. (2009). Accelerating preschoolers' early literacy development through classroom-based teacher–child storybook reading and explicit print referencing.Language, Speech, and Hearing Services in Schools, 40, 67–85.
  • Justice, L. M., McGinty, A. S., Cabell, S. Q., Kilday, C. R., Knighton, K., & Huffman, G. (2010). Language and literacy curriculum supplement for preschoolers who are academically at risk: A feasibility study.Language, Speech, and Hearing Services in Schools, 41, 161–178.
  • Kruse, L. G., Spencer, T. D., Olszewski, A., & Goldstein, H. (2015). Small groups, big gains: Efficacy of a Tier 2 phonological awareness intervention with preschoolers with early literacy deficits.American Journal of Speech-Language Pathology, 24, 189–205.
  • Law, J., Todd, L., Clark, J., Mroz, M., & Carr, J. (2013). Early language delays in the UK. London, United Kingdom: Save the Children. Retrieved from http://www.ncl.ac.uk/cflat/news/documents/Lawetal2013EarlyLanguageDelaysintheUK.pdf
  • Law, J., Tomblin, J. B., & Zhang, X. (2008). Characterizing the growth trajectories of language-impaired children between 7 and 11 years of age.Journal of Speech, Language, and Hearing Research, 51, 739–749.
  • Leonard, L. B., Ellis Weismer, S., Weber-Fox, C., & Miller, C. A. (2014). The role of processing in children and adolescents with language impairment.In J. B. Tomblin & M. A. Nippold (Eds.), Understanding individual differences in language development across the school years (pp. 117–143). New York, NY: Psychology Press.
  • Loeb, D. F., & Daniels, B. D. (2009). Administration of a literacy-based curriculum by teacher and SLP teams.SIG 16 Perspectives on School-Based Issues, 10(3), 73–77.
  • Lundberg, I., Olofsson, Å., & Wall, S. (1980). Reading and spelling skills in the first school years predicted from phonemic awareness skills in kindergarten.Scandinavian Journal of Psychology, 21, 159–173.
  • McMillan, J. H. (2008). Educational research: Fundamentals for the consumer (5th ed.). Boston, MA: Pearson.
  • Melby-Lervåg, M., Lyster, S.-A. H., & Hulme, C. (2012). Phonological skills and their role in learning to read: A meta-analytic review.Psychological Bulletin, 138, 322–353.
  • Milburn, T. F., Hipfner-Boucher, K., Weitzman, E., Greenberg, J., Pelletier, J., & Girolametto, L. (2015). Effects of coaching on educators' and preschoolers' use of references to print and phonological awareness during a small-group craft/writing activity.Language, Speech, and Hearing Services in Schools, 46, 94–111.
  • Ministry of Education, Science and Culture. (2011). Icelandic national curriculum guide for preschools. Retrieved from http://www.menntamalaraduneyti.is/utgefid-efni/namskrar/adalnamskra-leikskola/
  • Morgan, P. L., Farkas, G., & Wu, Q. (2011). Kindergarten children's growth trajectories in reading and mathematics: Who falls increasingly behind?.Journal of Learning Disabilities, 44, 472–488.
  • National Early Literacy Panel. (2008). Developing early literacy: Report of the National Early Literacy Panel. Washington, DC: National Institute for Literacy. Retrieved from http://lincs.ed.gov/publications/pdf/NELPReport09.pdf
  • National Institute of Child Health and Human Development Early Child Care Research Network. (2004). Multiple pathways to early academic achievement.Harvard Educational Review, 74, 1–29.
  • National Reading Panel. (2000). Report of the National Reading Panel. Teaching children to read: An evidence-based assessment of the scientific research literature on reading and its implications for reading instruction—reports of the subgroups. Washington, DC: National Institute of Child Health and Human Development.
  • Newcomer, P. L., & Hammill, D. (1988). Test of Language Development—Primary: Second Edition. Austin, TX: Pro-Ed.
  • Owens, R. E. (2008). Language development: An introduction (7th ed.). Boston, MA: Pearson.
  • Pence, K. L., & Justice, L. M. (2008). Language development from theory to practice. Upper Saddle River, NJ: Pearson.
  • Peterson, R. L., & Pennington, B. F. (2012). Developmental dyslexia.The Lancet, 379, 1997–2007.
  • Pickles, A., Anderson, D. K., & Lord, C. (2014). Heterogeneity and plasticity in the development of language: A 17‐year follow‐up of children referred early for possible autism.The Journal of Child Psychology and Psychiatry, 55, 1354–1362.
  • Rosner, J., & Simon, D. P. (1971). The Auditory Analysis Test: An initial report.Journal of Learning Disabilities, 4, 384–392.
  • Schuele, C. M., & Boudreau, D. (2008). Phonological awareness intervention: Beyond the basics.Language, Speech, and Hearing Services in Schools, 39, 3–20.
  • Seymour, P. H. K. (2005). Early reading development in European orthographies.In M. J. Snowling & C. Hulme (Eds.), The science of reading: A handbook (pp. 296–315). Malden, United Kingdom: Blackwell.
  • Silva, P. A., Williams, S., & McGee, R. (1987). A longitudinal study of children with developmental language delay at age three: Later intelligence, reading and behaviour problems.Developmental Medicine & Child Neurology, 29, 630–640.
  • Símonardóttir, I. (1996). Áreiðanleiki og réttmæti íslenskrar staðfærslu málþroskaprófsins TOLD-2P [Reliability and validity of the Icelandic version of TOLD-2P: Test of Language Development] (Unpublished master's thesis). Iceland University of Education, Reykjavík, Iceland.
  • Símonardóttir, I., Einarsdóttir, J., & Björnsdóttir, A. (2002). HLJÓM-2 handbók [HLJÓM-2 handbook]. Reykjavík, Iceland: Authors.
  • Símonardóttir, I., Guðmundsson, E., Skúlason, S., & Pétursdóttir, S. (1995). TOLD-2P. Málþroskapróf. Íslensk staðfærsla [TOLD-2P: Test of Language Development. Icelandic Version]. Reykjavík, Iceland: Rannsóknastofnun uppeldis-og menntamála.
  • Snowling, M. J., & Hulme, C. (2012). Interventions for children's language and literacy difficulties.International Journal of Language & Communication Disorders, 47, 27–34.
  • Statistics Iceland. (2014). Pre-primary institutions. Retrieved from http://old.statice.is/Statistics/Education/Pre-primary-institutions
  • Stothard, S. E., Snowling, M. J., Bishop, D. V. M., Chipchase, B. B., & Kaplan, C. A. (1998). Language-impaired preschoolers: A follow-up into adolescence.Journal of Speech, Language, and Hearing Research, 41, 407–418.
  • Tomblin, J. B. ( 2014). Educational and psychosocial outcomes of language impairment in kindergarten.In J. B. Tomblin & M. A. Nippold (Eds.), Understanding individual differences in language development across the school years (pp. 166–203). New York, NY: Psychology Press.
  • Tomblin, J. B., & Nippold, M. A. (2014). Features of language impairment in the school years.In J. B. Tomblin & M. A. Nippold (Eds.), Understanding individual differences in language development across the school years (pp. 79–116). New York, NY: Psychology Press.
  • Torgesen, J. K. (2002). The prevention of reading difficulties.Journal of School Psychology, 40, 7–26.
  • Torgesen, J. K., Wagner, R. K., & Rashotte, C. A. (1994). Longitudinal studies of phonological processing and reading.Journal of Learning Disabilities, 27, 276–286.
  • Vellutino, F. R., Fletcher, J. M., Snowling, M. J., & Scanlon, D. M. (2004). Specific reading disability (dyslexia): What have we learned in the past four decades?.The Journal of Child Psychology and Psychiatry, 45, 2–40.
  • 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.
  • Ziegler, J. C., Bertrand, D., Tóth, D., Csépe, V., Reis, A., Faísca, L., … Blomert, L. (2010). Orthographic depth and its impact on universal predictors of reading: A cross-language investigation.Psychological Science, 21, 551–559.

Additional Resources