Why do young readers vary in reading fluency? The impact of word length and frequency in French 6th graders

PurposeWhich processes induce variations in reading speed in young readers with the same amount of education, but different levels of reading fluency? Here, we tested a prediction of the dual-route model: as fluency increases, these variations may reflect a decreasing reliance on decoding and an increasing reliance on the lexical route. Method1,500 French 6th graders passed a one-minute speeded reading-aloud task evaluating fluency, and a 10-minute computerized lexical decision task evaluating the impact of word length, word frequency and pseudoword type. ResultsAs predicted, the word length effect varied dramatically with reading fluency, with the least fluent group showing a length effect even for frequent words. The frequency effect also varied, but solely in proportion to overall slowness, suggesting that frequency affects the decision stage in all readers, while length impacts poor readers disproportionately. Response times and errors were also affected by pseudoword type (e.g. letter substitutions or transpositions), but these effects did not vary much with fluency. Overall, lexical decision variables were excellent predictors of reading fluency (r=0.62). ConclusionOur results call attention to middle-school reading difficulties and encourage the use of lexical decision as a test of students mental lexicon and the automatization of reading.