The Nature of Inaccuracy among Readability Formulas.
Lynn S. Fuchs · 1983
The purposes of this study were to assess the useffiness of a variety of readability formulas in predicting the relative difficulty of passages. and to explore the contribution of pupils' background to text difficulty. Subjects were 285 special education students in grades 1-9, 117 of whom were based in rural and suburban Minnesota (MN) and 168 of whom lived in New York City (NYC). Each student was tested twice on three passages of a Passage Reading Test (PRT). Analyses of variance applied to the data revealed an interaction between passages and student site (MN vs NYC), suggesting that text difficulty was affected by students' background. Additionally, six readability formulas were applied to the three PRT passages. There was no agreement between pa-slage difficulty rankings derived from the formulas and those based on students' actual performance. Implications for creating readability formulas are discussed. The' Nature of Inaccuracy Among Readability Formulas Formulas for measuring the readability of, texts have been developed and employed widely for at least four decades (Kemper, 1983). Such formulas. may enjoy broad use due to their simplicity and hf.! ease with which educators can be taught to apply them,.as well as because of the appeal of such a seemingly scientific' approach to describing passage difficulty. Teachers rely on readability formulas for determining appropriate instructional reading material, and evidence (Stevens &'Roseoshine, 1981) suggests that the activity of matching reading material correctly with students' skills is important to student achievement. Nevertheless, the methods by which readability formulas are derived and the type of variables they include to predict text difficulty have been criticized (Fitzgerald, 1980; Fuchs, Fuchs, & Deno, 1982; Kemper, 1983). objective of, the present study was to address two frequently cited criticisms: (a) the poor accuracy of readability formulas, and (b) the serious omission from currently available formulas of variables that describe students' background or familiarity with text. Specifically, the study had two purposes: to assess the usefulness of a variety of readability formulas in predicting the relative difficulty of passages, using students' actual reading scores to determine the criterion difficulty of the passages, and to explore the contribution of pup,ls' backgrounds to text