What is the purpose of a Reading Composite on the WRAT 4 (Wide Range Achievement Test 4)?

Question

I am trying to understand why WRAT 4 using a reading composite

Answer 1

Achievement tests, like the WRAT4 (others are WJIII -achievement, WIAT-II, etc.), are most often used to test children to see if they qualify for special education services under Specific Learning Disability.  The composites of achievement tests are usually in the areas of math, reading, oral language, written expression, etc.  If a child's Achievement scores in one of these areas is significantly lower than their Intelligence score, they qualify for services.  So if a child's WRAT 4 reading composite was a 70, and they had an Intelligence score of 98 (as tested by an IQ test like the WISC IV, KABC2, WJ-III Cognitive), they would qualify for sevices as having a specific learning disability in reading.  (Typically, there needs to be a 22.5 point difference.)

This is the "traditional" way of qualifying students.  Studnets can also qualify for services through a different route (RTI) that doesn't rely on testing as I've explained above.  I hope this answers your question.  If I took a wrong direction, add some detail to your question and I'll try to help.

**Addition**

I've never given a WRAT, so I don't know specifics (I have given many other achievement tests).  BUT, the reading composite score is intended to reflect general reading ability.  A composite score is statistically more reliable than a subtest score.  That is why it is used when comparing to an IQ test.  A subtest may be as short as 10-20 questions.  So, if a kid was tired or anxious to get to recess during a subtest, it probably wouldn't be an accurate reflection of reading ability.  Composites take into account more aspects of a skill, such as reading.  Also they benefit from having more questions contributing to the score, which statistically "averages out" extraneous factors (tiredness, noise, attention, etc).

Achievement tests in general are not very prescriptive.  That is, they don't give much info on whether the reading problem is in reading is phonics, letter identification, phonemic awareness, etc.  Achievement tests are better at saying if there IS a problem, not really WHAT the problem is.  If you have a WRAT kit, the manual should have some rationale for the reading composite and subtests, but in my opinion, the purposes are often inflated by the publishers.

Ok, I hope I got it that time :)