Tuesday, April 10, 2007

Microsoft Word 2000 and Readability

When I mentioned to a group of technical communicators that Word has a ‘Readability’ feature, I had evoked mixed reactions within this group. A few reacted stating, ‘we know this’, some said, ‘You must be joking!’, and remaining were clean bowled by this Yorker asking, ‘Readability? What do you mean by that?’. Moreover, mind you, of the few that knew this, not all belonged to the ‘experienced’ category!

Thanks to the various mailing lists available for quite some time now, I had an insight into this topic some years’ earlier. Until then I had always wondered, when I saw reading levels marked on books, how these were determined.

I have read, on one of the mailing lists recently, of a wonderful system that companies like McGraw-Hill follow. McGraw-Hill’s publish lists that contain the book titles and the reading ease scores. These lists are circulated to all the public schools in America and all the books are marked with these readability scores. This helps students pick books based on their reading level!

To test the readability of a document in Word 2000:
1. Click Tools, Spelling and Grammar.
2. Click the Options button. Ensure that under Grammar, the ‘Check grammar with spelling’ and the ‘Show readability statistics’ checkboxes are checked. Click OK.
3. Click the appropriate ‘Ignore’, ‘Change’ and so on buttons until the complete document is checked for spelling and grammar. After completion, the ‘Readability Statistics’ details are displayed (screen capture above).

Measuring Readability
Readability measures are primarily based on factors such as the number of words in the sentences, and the number of letters or syllables per word (that is, as a reflection of word frequency). ‘Readability’ describes the ease with which a document can be read. Two of the most commonly used measures are the Flesch Reading Ease formula and the Flesch-Kincaid Grade Level.

The Flesch formula is
206.835 – (1.015 x ASL) – (84.6 x ASW)

The Flesch-Kincaid formula is
(.39 x ASL) + (11.8 x ASW) – 15.59


ASL = Average Sentence Length (the number of words divided by the number of sentences)ASW = Average number of Syllables per Word (the number of syllables divided by the number of words)

Rudolf Flesch developed the Flesch Readability Index to indicate the readability of military training manuals, which contain some technical language and unfamiliar terms. The output of the Flesch Reading Ease formula is a number from 0 to 100, with a higher score indicating easier reading. The average document has a Flesch Reading Ease score ranging from 6 to 70.
The Flesch-Kincaid Grade Level formula converts the Reading Ease Score to a U.S. grade-school level.

Reading Ease Score Reading Level U.S.grade-school level
0 to 30 Very difficult College level
30 to 40 Difficult High school or 1-2 years of college
50 Fairly difficult Some high school
60 to 70 Standard 8th and 9th grade students
80 to 90 Easy 5th grade students
90 to 100 Very easy 4th grade students

Literacy experts recommend that documents aimed at a large public audience should be written at the 5th grade level at the highest. A study reveals that the Flesch reading ease score for Reader’s Digest is 65 / standard, Time magazine is 52 / fairly difficult and that of Newsweek is 50 / fairly difficult.

Note: A text should generally have more than 200 words before the Flesch Reading Ease and Flesch-Kincaid Grade Level scores can successfully be applied.

So here’s hoping that next time one hears about readability, one might not remember the exact formula but will know what people are talking about!

Further reading:

To know more about the readability formulas and controversy surrounding them, read the article ‘The Principles of Readability’ by William H. Dubay, a senior member of STC and a plain?language consultant at Southern California.

Yamini Nafde is a Principal Technical Communicator with the Communication Design Group (CDG) at Infosys Technologies Limited, Pune. CDG specializes in user research, user interface design, user assistance, usability evaluation, multimedia, and graphic design.


Gautam Goswami said...
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Gautam Goswami said...

great post. I did not know about this feature of MS Word, before I read this blog. On running it over one document of mine, I got a healthy Flesch Reading ease score of 60!