The principles of readability are in every style manual. Readability formulas are in every writing aid. What is missing is the research and theory on which they stand. This short review of readability research spans 100 years. The first part covers the history of adult literacy studies in the U.S., establishing the stratified nature of the adult…

According to studies using the Degrees of Reading Power system for estimating readability, most high school graduates cannot read at a level enabling them to understand much of what they read in newspapers, periodicals, work-related documents, or many high school texts or tests. (PGD)

The purpose of this paper is to make classroom teachers on all educational levels aware of the limitations of readability formulas and the factors affecting readability that are not accounted for by the readability formulas. delineated in discussions of readability formula assumptions, problems, and limitations. Some of the specific factors that…