Listerine has led the mouthwash market for quite some time now. It was the first over-the counter mouthwash that was sold in the United States in 1914. In its early years, the company has promoted their product as a means of remedy for numerous illnesses. Its marketing techniques in the 1930s are evident in this article, which tells readers that Listerine can cure colds.
But is it really reliable?
Let's look at the article.
Now what exactly is "their number"? They didn't specify the basis or the previous condition they were in with a concrete value
It says that "their number often reduced 50% and sometimes 66%. One cold a year instead of three."
As we know, 1/3 of 100% is equal to 33.33%.
When we subtract 50% from 100%, we get 50% or 1/2 in fractions.
This could not be input in the scale of 1 cold a year instead of 3.
In turn, subtracting 66% from 100%, we get 34%. It is a slight distortion from the 33.33% that was specified earlier. The company decided to elaborate on that note.
In the next picture, we would see the contradiction between the data.
Now, the first statement "1/2 as many colds" can agree with the 50% value said in the first paragraph.
But, look at the test they conducted.
"204 persons in normal health were under observation for a period of one month to four-and-a-half months."
"Those who gargled with Listerine twice a day had from 50% to 66% fewer colds than those who didn't gargle with Listerine."
Wait.
Those results are exactly the same as the results in the first picture. But why do they have different time periods?
It cannot be possible that one cold a year instead of three be the same with one cold per one month to four-and-a-half months.
That experimental time period is also wrong. Can't they just decide on one concrete period instead of a range? How did they distribute the subjects accordingly?
Also, where are the results of the 1/3 who gargled 5 times a day?
"When Listerine users did contract colds, they were one-fourth as severe and lasted only one-third as long as the colds contracted by those who did not use Listerine."
The Severity of Illness (SOI) can be measured, but where is the previous value (or, as you can say, the 4/4)? There is also an absence of numerical values.
As for the duration of the colds, the same problem is seen. No hours, minutes, or seconds.
Well, at least we see a result for the people who gargled 5 times a day.
Resistance to infection or Immunity. No previous value.
Well, if you analyze the content of an article, you can further prove if it is reliable or not. This advertisement uses words that would entice the reader, but they are not accurate, therefore false.
Make sure you watch out for ads like these, you chump.
Sources:
http://en.wikipedia.org/wiki/Severity_of_illness
http://en.wikipedia.org/wiki/Listerine
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