One of the principal arguments for a coherent, content-rich
curriculum is that background knowledge — knowing something
about the topic you’re reading about – compensates for weak
reading ability. But how great is the effect? A tantalizing
article by reading researcher Tom Sticht on EdNews.org suggests
that in adult readers background knowledge can close a gap of
five grade levels of general reading ability. If you want to
test what someone knows about a subject, Sticht writes, “you
might give them a simple multiple choice test in a written
format, and then ask questions about the subject matter of
interest.” However this “confounds the assessment of the
person’s knowledge about the subject with their ability to
read.” In other words, it’s difficult to tell whether a person
taking a reading test doesn’t know the meaning of a word, for
example, can’t decode a word, or lacks the background knowledge
of the subject needed for adequate comprehension. As Sticht puts
it, we risk confusing ignorance with illiteracy.