Readability in technical writing-principles and procedures

Technical writers apparently show little concern with the measurement of readability, defined as level of reading comprehension. Some evidence and reasons for this indifference are presented. Three current methods of measuring readability are described. Two readability formulas involving word load and sentence load are the Dale-Chall, which uses a word-list, and the Fry, which uses a graph. The cloze procedure is a non-formula technique which involves the reader as well as the material being evaluated. The application of these methods is illustrated with passages of technical writing of varying difficulty. Some implications and applications of readability concepts are indicated.