Ebooks as Textbooks - Part 3 - Comfort and Text

Today's posting is about Fonts - their color, size and shape. I am always surprised that people don't change their display to what works best for them in the situation that they are in. Many times dealing with people I've seen situations where they want the text to look in a way that makes it harder for them to read. For example a recent situation with a person who was having trouble reading from the screen. I did a basic change to the display size to 120%. She thought it looked great and was much easier to read, but when I explained what I had done, she changed it back to 100% - making it harder for her to read again as she wanted for it to look just how it was going to be when printed. I've seen this too with ebooks. Some people want it to have the same page appearance as their paperback books with the font using Times and the size being between 10 and 12 points. One of the great thing about ebooks is that you are not limited to the display being preset, instead you can adjust it for your preferences and situation. With ebooks you can make your reading fit your own Goldilocks Principle, not too big, and not too small, make the text just right for you and your situation. I find for myself that under lower light levels or when I read in a moving vehicle, I move the text size up as compared to when I reading in a room or outdoors with good light.

There are in essence three aspects to look at in using your ebook device or program to read your etextbook: (1) what is the best font size for you when reading your ebook or etextbook, (2) which font type is best for your reading, although you may only be able to change between serif or san serif, and (3)  which background is the best for your reading situation - the background question doesn't apply to eInk devices like the Kindle, but ebook programs on computers or tablets may give you options.

First lets consider how people actually read. When you look at text you start the reading process, in this there are a series of saccades and fixations. The sccades are the movements and the fixatations are when your eye stops and focuses on a discrete chunk of text -  a process that is repeated over and over again on every line. A fixation is a brief moment, around a quarter of a second, when the eye is stopped on a word or collection of letters. The saccade is the forward in the text jumping about 8-12 characters, to the next position (fixatations). Other movements include regressions, where you move backwards in the text, and reread (usually indicative of confusion) and then there are return sweeps, where the eye moves to the beginning of the next line. So what does this have to do with your etextbook? It should also be about reading in confort and understanding that you can adjust the size and shape to be the best fit for you when reading - although as a side note: it has been found that you will remember more when having a hard time reading (decoding text that is difficult to read). 

Consider how long it will take to read a portion of your etextbook. You might think that you should make the font as small as possible to be able to read faster (fewer return sweeps). But, this will not always be true, as when researchers studying font size and font type found that when they changed the font from 10 points to 6 points, reading speed actually went down (6 pt font was slower due to increased fixation duration, probably 
caused by reduced character visibility). When they increase the font size to 14 pt, reading also slowed down (more fixations as fewer letters fit in the chunk viewing size) - although this has been challenged by other studies that find that that saccade size is dependent on the character spacing, and should scale up for larger fonts, so not impact reading speeds. So for  font sizes, having a font that is too small makes the text illegible, and one that is too large can waste a lot of space. 

So what is the best font size? That will depend on you your personal abilities, limitations, and situations. Many people find that a small increase in font size (+2pts) makes text much easier to read. People may think of large print books for the elderly, but that doesn't mean that it has to only be for older readers. Studies have found that large print books being used by students with no visual problems increased their speed and comprehension. A Kindle study of middle schoolers reported that when reading with an increased font size that students were able to read easier and faster. Another study with elementary students found that using large print books found an improvement of between 41 and 70 percent of student's SRA Reading scores after a year.  Then too there have been studies that have shown that showed a decrease in reading errors with an increase in font size (24-point versus 9- and 12-point) for reading disabled children (Cornelissen, Bradley, Fowler, and Stein 1991). Additionally increasing the line spacing to at least 1.5 can assist by separating out the text. Personally I have found that an increased font size helps a great deal when reading in less than idea environments, such as poorer lighting or while moving as the stop and start movement, background noise and vibrations could all have an effect on reading (such as in a car or bus, although I have been known to walk and read). Usually students develop the ability to decode text that is smaller as they become older and more experienced with the process of reading. So along a reading ability (no eye issues) then larger text in books for early readers reflects a developmental stage. So this suggests that you should increase the font size for younger students who may need a larger print to increase reading performance. This also means that as this is a developmental stage in reading that struggling readers or those new to the language should also be assisted in their reading with an increased font size.   

The research doesn't provide much concerning any real differences between serif or san serif fonts. But some do state that the extra bits and thicknesses with serif fonts makes the letters and words more distinctive and therefor easier on the eye for reading. Often the font type effects are more associated with experience, as when young the letters are usually san serif fonts, using a much cleaner and simpler letter structure, but as we get older we are more exposed to serifed fonts, like times, and so become used to those. Older students then usually prefer a serifed font, in other words the one that they are more used to. Making the font the one that you are used to make it easier for your brain to process the information - less effort is put into decoding. One issue to also think about for font type can be how well it can be when displayed on an ebook screen, as screens have a resolution - it may be that when reading on a screen (eink or lcd) that a sarifed font may blur a bit because of resolution causing readers to slow down, so it would be better then to use a different font such as one designed for screen reading.

When considering color, most people actually prefer dark text on a light background, but this isn't for everyone. For example if you are reading in a dark room using a lcd display it may be more comfortable to have light text on a dark background - the reduction in brightness of the background can reduce eye strain. Students with dyslexia may prefer a screen display that isn't white as the white can appear too dazzling. 

Here are some findings from research studies concerning text display-
  • Size of characters is important for legibility. After characters are legible, their size has less of an impact reading speed.
  • Children below 7 prefer font size 24 and those aged 7 or 8 prefer font size 18 - font size preference decreases though elementary and middle school and increases through latter adulthood.
  • Dyslexic students need a critical font size to be able to reach their highest reading speed and this is higher than that for non-dyslexic students.
  • Black characters on a white background produce the best readability in standard conditions.
  • Increasing the spacing between lines improves clarity.
  • Harder to read fonts can improve memory of the text at the cost of effort.
The end result should be that you or your students should find which font size, color and shape works best for them, along with the appropriate spacing and color. Everybody isn't the same, and now all our books don't have to look exactly alike. Ebook devices and programs have differentiated instructional elements built in to their display if we just start using them. Readers should take the time with their ebooks and etextbooks to find what works best for them in a variety of situations and remember to adjust their etextbooks for those situations. 

Cornelissen, P., Bradley, L., Fowler, S. & Stein, J.  (1991). What children see affects how they read. Developmental Medicine and Child Neurology 33 (1991), pp. 755762.