Though created for children's reading, Lorge's formula was soon widely used for adult material as well. Where Gray and Leary's formula had five elements, Lorge's had three, setting a trend that was to follow:
- Average sentence length in words
- Number of prepositional phrases per 100 words
- Number of hard words not on the Dale list of 769 words.
Lorge's use of the McCall-Crabbs Standard Test Lessons in Reading as a criterion of difficulty greatly simplified the problem of matching readers to texts (Klare, 1985). Although these passages were far from ideal, they had fewer faults than other passages used as criteria. They remained the standard for readability studies until the Bormuth studies in 1969.
The problem of communication to masses of people became especially obvious during World War II. The government bureaus and the armed services needed efficient ways of assessing the readability of their materials. Lorge's formula was one of the first, and it came into wide use (Klare and Buck, p. 59).
Rudolf Flesch and the art of plain writing The one perhaps most responsible for publicizing the need for readability was Rudolf Flesch, a colleague of Lorge at Columbia University. Besides working as a readability consultant, lecturer, and teacher of writing, he published a number of studies and nearly 20 popular books on English usage and readability. His best-selling books included The Art of Plain Talk (1946), The Art of Readable Writing (1949), The Art of Clear Thinking (1951), Why Johnny Can't Read - And What You Can Do About It (1955), The ABC of Style: A Guide to Plain English (1964), How to Write in Plain English: A Book for Lawyers and Consumers (1979).
Flesch was born in Austria and got a degree in law from the University of Vienna in 1933. He practiced law until 1938, when he came to the U.S. as a refugee from the Nazis.
Fig. 6. The first edition of The Art of Plain Talk in 1946 by Rudolf Flesch was a best seller. The readability formulas it featured started a revolution in journalism and business communication.
Since his law degree was not recognized, he worked several other jobs, one of them in the shipping department of a New York book manufacturer.
In 1939, he received a refugee's scholarship at Columbia University. In 1940, he received a bachelor's degree with honors in library science. That same year, he became an assistant to Lyman Bryson in the Teachers' College Readability Lab.
In 1942, Flesch received a master's degree in adult education. The next year, he received a Ph.D. in educational research for his dissertation, "Marks of a Readable Style" (1943). This paper set a course for his career and that of readability.
In his dissertation, Flesch published his first readability formula for measuring adult reading material. One of the variables it used was affixes and another was "personal references" such as personal pronouns and names. Publishers quickly discovered that Flesch's formula could increase readership by 40 to 60 percent. Investigators in many fields of communication began using it in their studies.
In 1948, Flesch published a second formula with two parts. The first part, the Reading Ease formula, dropped the use of affixes and used only two variables, the number of syllables and the number of sentences for each 100-word sample.