Editing Readability (section)

=== Readership formula adoption ===

In 1943, Rudolf Flesch published his PhD dissertation, ''Marks of a Readable Style'', which included a readability formula to predict the difficulty of adult reading material. Investigators in many fields began using it to improve communications. One of the variables it used was ''personal references,'' such as names and personal pronouns. Another variable was ''affixes''.<ref name="FleschStyle">Flesch, R. "Marks of a readable style." ''Columbia University contributions to education,'' no. 187. New York: Bureau of Publications, Teachers College, Columbia University.</ref>

In 1947, Donald Murphy of ''Wallace's Farmer'' used a split-run<ref name="Murphy2">Murphy, D. 1947. "How plain talk increases readership 45% to 60%." ''Printer's ink.'' 220:35–37.</ref> edition to study the effects of making text easier to read. He found that reducing from the 9th to the 6th-grade reading level increased readership by 43% for an article about 'nylon'.  He also found a 60% increase in readership for an article on corn, with better responses from people under 35.<ref name="Murphy2" /> The result was a gain of 42,000 readers in a circulation of 275,000.

Wilber Schramm, who directed the Communications Research program at the University of Illinois interviewed 1,050 newspaper readers in 1947. He found that an easier reading style helps to determine how much of an article is read. This was called reading persistence, depth, or perseverance He also found that people will read less of long articles than of short ones, for example, a story nine paragraphs long will lose 3 out of 10 readers by the fifth paragraph. In contrast, a shorter story will lose only 2 out of 10 readers.<ref name="Schramm">Schramm, W. 1947. "Measuring another dimension of newspaper readership." ''Journalism quarterly'' 24:293–306.</ref>

A study in 1947 by Melvin Lostutter showed that newspapers were generally written at a level five years above the ability of average American adult readers. The reading ease of newspaper articles was not found to have much connection with the education, experience, or personal interest of the journalists writing the stories. It instead had more to do with the convention and culture of the industry. Lostutter argued for more readability testing in newspaper writing. Improved readability must be a "conscious process somewhat independent of the education and experience of the staffs ''writers.''"''<ref name="Lostutter">Lostutter, M. 1947. "Some critical factors in newspaper readability." ''Journalism quarterly'' 24:307–314.</ref>''

In 1948, Flesch published his [[Flesch–Kincaid readability tests|Reading Ease]] formula in two parts. Rather than using grade levels, it used a scale from 0 to 100, with 0 equivalent to the 12th grade and 100 equivalent to the 4th grade. It dropped the use of affixes. The second part of the formula predicts human interest by using personal references and the number of personal sentences. The new formula correlated 0.70 with the McCall-Crabbs reading tests.<ref name="FleschEase">Flesch, R. 1948. "A new readability yardstick." ''Journal of Applied Psychology'' 32:221–33.</ref>

In 1948, Bernard Feld did a study of every item and ad in the ''Birmingham News'' of 20 November 1947. He divided the items into those above the 8th-grade level and those at the 8th grade or below. He chose the 8th-grade breakpoint, as that was determined to be the average reading level of adult readers. An 8th-grade text "...will reach about 50% of all American grown-ups," he wrote. Among the wire-service stories, the lower group got two-thirds more readers, and among local stories, 75% more readers. Feld also believed in drilling writers in Flesch's clear-writing principles.<ref name="Feld">Feld, B. 1948. "Empirical test proves clarity adds readers." ''Editor and publisher'' 81:38.</ref>

Both Rudolf Flesch and Robert Gunning worked extensively with newspapers and the wire services in improving readability. Mainly through their efforts in a few years, the readability of US newspapers went from the 16th to the 11th-grade level, where it remains today. Publishers discovered that the Flesch formulas could increase readership up to 60%. Flesch's work made an enormous impact on journalism. The Flesch Reading Ease formula became one of the most widely used, tested, and reliable readability metrics.<ref name="Klare63">Klare, G. R. 1963. ''The measurement of readability''. Ames, Iowa: University of Iowa Press.</ref><ref name="Chall">Chall, J. S. 1958. ''Readability: An appraisal of research and application.'' Columbus, OH: Bureau of Educational Research, Ohio State University.</ref> In 1951, Farr, Jenkins, and Patterson simplified the formula further by changing the syllable count.<ref name="Farr" />