SMOG

The SMOG grade is a measure of readability that estimates the years of education needed to understand a piece of writing. SMOG is an acronym for "Simple Measure of Gobbledygook".

SMOG is widely used, particularly for checking health messages.[1][2] The SMOG grade yields a 0.985 correlation with a standard error of 1.5159 grades with the grades of readers who had 100% comprehension of test materials.[3]

The formula for calculating the SMOG grade was developed by G. Harry McLaughlin as a more accurate and more easily calculated substitute for the Gunning fog index and published in 1969. To make calculating a text's readability as simple as possible an approximate formula was also given — count the words of three or more syllables in three 10-sentence samples, estimate the count's square root (from the nearest perfect square), and add 3.

A 2010 study published in the Journal of the Royal College of Physicians of Edinburgh stated that “SMOG should be the preferred measure of readability when evaluating consumer-oriented healthcare material.” The study found that “The Flesch-Kincaid formula significantly underestimated reading difficulty compared with the gold standard SMOG formula.”[4]

Applying SMOG to other languages lacks statistical validity.[5]

  1. ^ Hedman, Amy S. (January 2008). "Using the SMOG formula to revise a health-related document". American Journal of Health Education. 39 (1): 61–64. doi:10.1080/19325037.2008.10599016. S2CID 72389214. Retrieved 2009-01-19.
  2. ^ Ley, P.; T. Florio (February 1996). "The use of readability formulas in health care". Psychology, Health & Medicine. 1 (1): 7–28. doi:10.1080/13548509608400003.
  3. ^ McLaughlin, G. Harry (May 1969). "SMOG Grading — a New Readability Formula" (PDF). Journal of Reading. 12 (8): 639–646. Retrieved 2018-04-26.
  4. ^ Fitzsimmons, P.; Michael, B.; Hulley, J.; Scott, G. (2010). "A readability assessment of online Parkinson's disease information". J R Coll Physicians Edinb. 40 (4): 292–6. doi:10.4997/JRCPE.2010.401. PMID 21132132.
  5. ^ Contreras, A.; Garcia-alonso, R.; Echenique, M.; Daye-contreras, F. (1999). "The SOL Formulas for Converting SMOG Readability Scores Between Health Education Materials Written in Spanish, English, and French". Journal of Health Communication. 4 (1): 21–29. doi:10.1080/108107399127066. PMID 10977275.