Validation of the Norwegian International Reading Speed Texts (IReST) in adult readers with normal vision




reading speed, paragraph reading, reading performance, sentences, text reading, reading test


There is a lack of standardised reading tests in Norwegian suitable for adults and persons with visual impairment (VI). The International Reading Speed Texts (IReST) measure reading performance of longer paragraphs. The aim of this project was to translate and validate the IReST in Norwegian. Each of the German, English and Swedish IReST were translated into Norwegian. The translations were matched for length, linguistic difficulty, and structure, and piloted in five adults. Reading speed was assessed in 25 readers (41 years, SD = 10) with normal vision and the readings were recorded. Reading speeds were analysed for variability between texts and participants. There were no statistically significant differences between the ten texts (135 words, 765 characters [SD=18], word variation index 91.8% [SD = 0.9%]). Reading speed in adult readers was 204 (SD=31) words/min. There was no difference across texts for any of the participants (p>0.05). Reading speed variance was 77.4% between subjects and 22.6% between texts. The Norwegian IReST is standardised and comparable to the international IReST tests. Reading speed falls within normative values in adult readers. The Norwegian IReST will be a valuable tool in assessing reading in clinical health care, rehabilitation and educational practice of adult and visually impaired readers and in reading research.


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How to Cite

Nachtnebel, D. A., & Falkenberg, H. K. (2024). Validation of the Norwegian International Reading Speed Texts (IReST) in adult readers with normal vision. Scandinavian Journal of Optometry and Visual Science, 17(1), 1–5.



Scientific Article