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Type & Layout, by Colin Wheildon
ISBN 0-9624891-5-8. 1995, Strathmoor Press (2550 Ninth Street, Suite
1000, Berkeley, CA 94710).
This book contains the results of a nine-year study on the effects of
typography and design on a reader's understanding of printed material.
In the study, articles with varying typographic and design elements
were presented to 224 participants. Participants read the pieces, then
took short (10-question) tests to reveal their understanding of the
material contained in the articles. Participants were also asked other
questions about some pieces to determine preferences for particular
typographic and design elements.
Wheildon's major conclusions follow.
American typographer and teacher Edmund Arnold devised a model called
the Gutenberg Diagram, which asserts that a reader's eyes naturally
fall at the top left corner of a page (which he calls the Primary
Optical Area), then move across and down the page. After each
left-to-right sweep, the eyes return to the horizontal point at which
they expect the next line to begin (which he calls the Axis of
Orientation, and which is represented by the left margin of a text
column). In sum, these principles govern the manner in which a
reader's eyes move over a page, referred to as "reading gravity."
Arnold's model, however, was based on opinion and anecdotal
Wheildon's study validates the principles of reading gravity.
Specifically, his study showed that more than twice as many readers
understand text presented in a layout that complies with reading
gravity than one that defies it.
Serif Type vs. Sans Serif Type in Body Text
According to this study, more than five times as many readers are
likely to show good comprehension of text printed in serif type than
sans serif type.
Type Style in Headlines
There is little difference in legibility between headlines set in
serif and sans serif type, or between roman and italic.
Headlines set in capital letters are significantly less legible than
those set in lowercase.
Tightly tracking headline type (decreasing letter and word spacing)
Slightly condensing headline type makes it easier to read. Settings
between 70% and 90% of natural width appear to be optimal.
Color and Type
Study participants revealed an interesting dichotomy regarding type
and color. Readers considered layouts with colored text to be more
attractive, but their comprehension of colored text was distinctly
lower (and for some colors, much lower) than black text.
The darker the headline, the better the comprehension. Black headlines
were well understood by nearly four times as many readers as headlines
in bright, high-intensity colors (such as bright yellow, orange, red,
and lime green).
Print body text in black. Even copy set in dark colors was
substantially more difficult for readers to understand. Seven times as
many participants demonstrated good comprehension of black text
compared to high-intensity or muted colors.
Black text printed on a light tint is both attractive to readers and
has high comprehensibility.
When black text is printed on a grey background, readers have
difficulty discerning words when the background screen is greater than
Reversed text is virtually impossible for readers to understand. This
is true of both serif and sans serif type.
Printing running text in bold undermines reading comprehension. Less
than half of readers will easily understand the message.
Conventional wisdom has always held that italic type is more difficult
to read than roman type. According to this study, however, this is
false--italic body type caused no more difficulty for readers than
roman body type.
Justification vs. Ragged Setting
Readers show the best comprehension with fully justified text. Almost
twice as many readers understand justified text than text set ragged
right. Seven times as many readers show good comprehension of
justified compared to ragged left.
Periods at the End of Headlines
Placing periods at the end of headlines may have a detrimental effect
on readers' comprehension.
Other Typographical Elements
Readers are easily annoyed by things that are often considered "good"
design. Most participants complained about articles in which body type
jumps over an illustration or pull quote; special screening effects on
illustrations; and headlines more than four lines long.
Readers also complained about jumps (articles that begin on one page
and continue on another). Four out of five readers claim to disobey
Readers prefer captions over descriptions in accompanying text.
Most readers find subheads useful, especially in long articles.
Running text set in either long lines (>60 characters) or short lines
(<20 characters) are hard to read.
Text set in capitals is difficult to read.
Type Size for Body Text
In a separate study comprising 4,000 participants, about 75% found it
easy to read type within the range of 10-point type on 11-point
leading (10/11) and 12-point type on 14-point leading (12/14).
Wheildon discusses his research methods in an appendix to the book,
and they appear to be valid. I would have liked to see a larger
sample, however. (The sample size was 224.) With the exception of a
few high school students, all participants were at least high school
graduates; many were more educated. This means that his sample is
better educated than the general population. (In my opinion, this
would probably only make his results more polarized along current
Regarding manipulation of headline type (tracking and condensing):
this study didn't outline other design criteria that accompany the
decision to manipulate type, such as the length of the headline, the
size of the type, the quality of the type, and the ability of the word
processor or DTP program to adjust type in an optically correct
fashion. For example, a high-quality headline type may already be
optically adjusted for spacing and width.
Regarding justification: this study didn't say what the line length
was for justified type samples. Line length is a major consideration
in justified type, since it is harder to set attractive justified type
the shorter the lines. Also not mentioned were the limitations of DTP
tools. Some word processors and DTP programs do such an abominable job
of spacing justified type that it might actually increase readability
to use a ragged right setting. Finally, the study didn't address the
affect of hyphenation on comprehension, which is a major variable in
setting justified type.