Writing question -Reply

[Elizabeth Gregory]

In terms of typography, Colin Wheildon has done several studies on the effect of all-capitals versus capitals-and-lower-case (among many other variables, like serif versus sans-serif type, reversed type on a dark background, etc.) on readability and comprehension.

He reports his findings in _Type and Layout_ (1996, Strathmoor Press).

I'm not aware of similar research done for other media, such as computer screens, etc., or for handwriting.

A quick synthesis of the theory of type, design, and readability I've read:

For passages of text (as opposed to headings or headlines), anything that makes letters look more different from each other aids readability, by allowing words to be read more quickly and easily.

In all-caps, all the letters are basically the same shape (a large square), so an important means of differentiation is lost. Each letter must be recognized individually, so reading becomes slower and more tedious.

Hope this helps.

Elizabeth Gregory
Assistant Professor and
Extension Communications Specialist
Texas Agricultural Extension Service
The Texas A&M University System