The admirable Mr. Wheildon's research had very limited distribution until recently. Now, thank goodness, it's available in a reprinted edition on Amazon. Still, beware: no designer I've yet encountered knows of this critical research. And when they DO hear of it, they argue against it. Go figure.
Data below shared with Colin Wheildon's permission, from the U.S. edition of his work, Type & Layout: How typography and design can get your message across - or get in the way (1995, Strathmoor Press, Berkeley).
To order the reprinted edition of his book from Amazon, click here.
Which typeface is better: Serif or sans serif?
In print, definitely go with a serif typeface such as Times New Roman, at least in the U.S., Canada or Australia (where Colin Wheildon conducted his very rigorous research).
Mr. Wheildon's researchers found that a serif typeface like Times New Roman is more than FIVE TIMES easier for average readers to comprehend than a SANS serif type such as Helvetica or Arial.
The reason? I'm speculating here, but I suspect it's because probably 95% of what you typically read (books, newspapers, magazines) is typeset in a serif font like Times. I.e., your brain trains daily on serif typefaces, learning to recognize their characteristic letterforms at high speed. Encountering a sans serif typeface instead, your brain slows to a crawl, because the letterforms are less familiar. That's my crackpot theory, anyway.
The Web, though, is not a printed page. For the Web, I've heard many people say they prefer reading a sans serif face like Arial. I'm not sure I disagree. (Although I'm not aware of any definitive research at this time.) Computer monitors are crude. With a mere 72 dot-per-inch resolution, they don't display serif type like Times particularly well.Reverse type: A big zero
What printers and designers call "reverse type" is white text set against a black or colored background. Many designers seem to feel that reverse type makes no difference to the reader. They are catastrophically wrong, Mr. Wheildon's research found. Here's the science:
When text was printed black on white, readers reported good comprehension 70% of the time, fair comprehension 19%, and poor comprehension 11% of the time.
When text was printed white on black, good comprehension fell to ZERO, while poor comprehension rose to 88%.
Enough said? Not quite. After revealing this bombshell, I'm often asked, "Can I ever use reverse type?" Absolutely. Use it for secondary information, stuff that doesn't matter.Colored type: Deceptively pretty
Shown two samples of body copy, one printed in black and one printed in a color, readers will often say they prefer the colored sample.
Don't you believe it.
Colin Wheildon tested black text against four other colors (deep purple, French blue, olive green, and cyan). In every case, the black text proved to be significantly easier to comprehend.
"On being shown pages printed in black and in cyan, 90 per cent said they found the black page boring when compared with the blue printed page," Mr. Wheildon reported. Cyan is an intense light blue, one of the four ink colors used in full-color offset printing.
But in the laboratory, 70% of these same people found black text easy to comprehend, while only 10% found cyan text easy to comprehend. Poor comprehension for black text was a mere 11%, but rose to 81% for text printed in cyan.Colored backgrounds: Use sparingly
Like colored text, colored backgrounds behind text look pretty, but can seriously degrade the reader's ease of comprehension.
Even a seemingly innocuous background color such as pale blue has pretty dire consequences.
As noted above, when text was printed black on white, readers reported good comprehension 70% of the time, fair comprehension 19%, and poor comprehension 11% of the time.
With text printed on a pale blue background, good comprehension fell to 38% while poor comprehension rose to 43%.