| Share: | More

4 Apr 2002

The Critical Word Factor in Texts for Beginning Readers: Effects on Reading Speed, Accuracy, and Comprehension

Elfrieda H. Hiebert & Charles W. Fisher, University of Michigan

Journal Article

Hiebert, E.H., & Fisher, C.W. (2007). The critical word factor in texts for beginning readers. Journal of Educational Research. 101(1), 3-11. Paper was also presented at the annual meeting of the American Educational Research Association, New Orleans, LA


This paper examines the effects of differences in the difficulty of texts on the speed, accuracy, and comprehension of beginning readers. Text difficulty was measured by the Critical Word Factor (CWF), an index of the word recognition demands of texts. The CWF is a function of the number of new, unique words per 100 running words of text that fall outside a designated group of high-frequency and phonetically decodable words. A common curriculum at the beginning of first grade consists of the 100 most-frequent words in written English and words that have a single grapheme representing a single phoneme (as in go and cat).

Thirty-six children completing their first trimester of first grade read four texts in a randomized order. Two texts had high CWFs, indicating a substantial portion of unique words beyond the 100 most-frequent words and words with relatively complex vowel patterns. Two other texts had low CWFs, indicating that unique words were limited to the designated curriculum of 100 most-frequent words or words with simple vowels.

Analyses of variance indicated that there were strong main effects for CWF on reading speed, accuracy and comprehension. All three variables were in the direction predicted by the model with the results for speed and accuracy being stronger than those for comprehension. Supplementary support for the model was provided by descriptive analyses. When means on speed, accuracy, and comprehension were examined by quartile (based on word recognition scores), 46 of 48 results were predicted by the model (two reversals occurred on comprehension). In addition, words predicted by the model to be hard were hard and those predicted to be easy were easy.