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…

The purpose of this book is to introduce the research on readability, defined here as reading ease. The first part of the book covers how people read. A series of national literacy surveys show that the average person in the U.S. and most other countries are adults of limited reading skills. For example, the average adult in the U.S. reads at the…

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)

This study examined the effect of two ways of question phrasing as related to three styles of expository writing on the test performance of elementary school children. Multiple-choice questions were developed for sets of passages which were written using three different syntactic structures; and which had different levels of difficulty. The…