Some readability formulas refer to a list of words graded for difficulty.

In practice, however, the utility of simple word and sentence length measures make them more popular for readability formulas.

Not necessarily, since both teachers and researchers will ultimately use readability formulae for just so long as they find them of some value.

The readability formulas could be used to select and create literature and texts of different reading levels.

Most of the basic research on the readability formulas was done in the first half of the 20th century.

A second look at the validity of readability formulas.

By the year 2000, there were over 1,000 studies on readability formulas in professional journals about their validity and merit.

It was thought too difficult for students since it failed to meet grade appropriate "readability formulas."

Or maybe it was the "readability" formulas that, among other things, limited the number of multisyllabic words she could use in a sentence.

States still decide what subjects the books must cover, they add, and many school districts still cling to readability formulas.