There are two types of tests involved when you are dealing with dyslexia.  A screening test and a comprehensive test.  The primary purpose of the screening test is to determine if the more comprehensive test is needed.  Here are some reasons why this is important.

A dyslexia screening test is a fairly simple test which does not necessarily determine if a person has dyslexia.  It is used to determine if a person has some sort of learning disability whether it is ADD, ADHD, dyslexia or even autism.  It is just as often used to screen people out of a learning disabled group as it is to screen them for a disorder.  This is important so that valuable resources can be put to use where they are most needed and where they will do the most good.

Even the screening test process can consist of several stages.  In it's simplest form, the screening test is just a list of items that a learning disabled person might exhibit.  If several of these are found to be true about the test subject, then that may be an indication that further testing is warranted.  From there, a consultation with an educator or psychologist who specializes in dyslexia might be the next step.  They may want to see the child in person, or conduct a different type of screening test, such as a computer game, if a child is involved.  They will also want to ask many more questions both of the subject, if it's an adult or teen, and the subject's, parents and teachers, if it is a child.

Another big reason for the screening test is to avoid the more comprehensive test whenever possible.  The comprehensive test is much more difficult, time consuming, expensive and laborious for the person being tested.  It can often take several testing sessions.  In some versions the comprehensive tests consists of as many as twelve separate tests.  If you were to try to start with the comprehensive test and find out the person does not have dyslexia, it would be a tremendous waste of time and money and would create unnecessary stress for the person being tested.

So, the dyslexia screening test is a process in and of itself.  It is an important first step and a valuable tool in determining if a person has dyslexia and if further testing is needed.  It can prevent a lot of frustration and lost time in creating a learning plan for someone who has the disability.  People who suspect they may have dyslexia or are trying to help someone who may have dyslexia should consider a screening test as their first option.