What are "Readability Formulas"?
You can use "readability formulas" to measure the difficulty of words and sentences in any written materials. You can choose from several dozen readability formulas, including the Fry formula, SMOG, Dale-Chall Formula, and Flesch tests (Flesch-Kincaid and Flesch Reading Ease). Because readability formulas vary in purpose and calculation, most writers use no more than three similar formulas on a document. Readability formulas estimate text difficulty based on the length of words and sentences. All readability formulas output a result equivalent to a grade level, such as
fourth grade or 12th grade.
The examples below will help you better understand how word choices and sentence length can affect ease of reading. Paragraphs A, B, and C each show similar content written at three different grade levels. Can you guess the grade levels? Notice how each example varies in vocabulary and sentence length.
What grade level do you think it is?
"It makes good sense that premature births and newborn illnesses are decreased by early pregnancy care. doctor is actively involved in testing pregnant woman for induced diabetes host other problems would not be detected patient alone. We know that these problems cause premature births and illness in newborns. It certainly makes sense that earlier detection and of these problems by the doctor results healthier babies."
"If you are pregnant or think you may be pregnant, call for an appointment right away. Getting care early in your pregnancy will help have a healthy pregnancy and a healthy baby. Your PCP (or an OB-GYN doctor you choose from your network) will give you certain tests to make sure everything is going well. If there are any problems, it's good find them early. That way, you have the best chances for a healthy baby."
"If you are pregnant or think you might be, go to the doctor as soon as you can. If you start your care early, things will be better for you and your baby. Your own doctor or childbirth doctor from our list will give you a first exam. Testing every month will let you know if all is going well. If there is a certain problem, you'll know it right away. Then we can do what is needed. Early care is the best way to have a healthy child. Your baby counts on you."
Answer: Approximate grade levels are:
- A. 12th grade.
- B.8th grade.
- C.4th grade.
Be cautious when you use readability formulas.
Readability formulas ignore many factors that assess to ease of reading and comprehension, including the active role of the reader. Relying on a grade level score can mislead you into believing that readers can read and understand your materials when, in fact, they cannot.
Grade level scores for the same text can differ considerably depending on your choice of formula and how you use it. Grade level scores are less precise than they sound and it is tempting to over-interpret what they mean.
Enforcing a grade level requirement has the potential to do harm. To make text scores at a lower grade level, you need to shorten words and sentences. Sometimes this improves ease of reading, but it can also lead to edits that reduce the ease of reading. For example, writers might remove familiar words just because they are long. Overall, writers may produce text that is choppy and lacks cohesion because they want to meet a specific grade level.