Table 1.

Readability metrics used for analysis

Test	Score type	Qualities assessed	Formula
Coleman-Lieu	Grade level	Word length sentence length	G = ((5.88*C)/W) − ((29.5*S)/W) − 15.8
Flesch-Kincaid	Grade level	Word complexity sentence length	G = (11.8*(B/W)) + (0.39*(W/S)) − 15.59
Flesch Reading Ease	Index score range (0–100; 100 = easiest)	Word complexity sentence length	I = 206.835 − (84.6*(B/W)) − (1.015*(W/S))
FORCAST	Grade level	Word complexity	G = 20 − (M/10)
Fry Graph	Grade level	Word complexity sentence length	1. Extract 100 word samples 2. Count number of sentences 3. Count number of syllables 4. Plot on the Fry Graph 5. Fry score = average of samples
Gunning Fog	Grade level	Word complexity sentence length	G = 0.4*(W/S + ((X/W)*100))
New Dale-Chall	Grade level	Word familiarity sentence length	G = (0.0496*(W/S)) + (0.1579*(U/W)) + 3.6365
New Fog Count	Grade level	Word complexity sentence length	G = (((E+(3*X))/S) − 3)/2
Raygor Estimate	Grade level	Word length sentence length	1. Extract 100 word samples 2. Count number of sentences 3. Count number of words >6 letters 4. Plot on the Raygor graph 5. Raygor estimate = average of samples
SMOG	Grade level	Word complexity sentence length	G = 1.0430*√X + 3.1291

G grade level, I index, W number of words, C number of characters, S number of sentences, B number of syllables, M number of monosyllabic words, X number of complex words (>3 syllables), E number of unfamiliar words (based on a list of 3000 common words known to average fourth grade students)