The OLSAT isn't an IQ test. It is an ability test.
Accuracy
The fact that the OLSAT is easier and less expensive to administer than an IQ test, such as the Stanford Binet V or the Wechsler Intelligence Scale for Children, makes it more accessible; but its accuracy at higher levels is less reliable.[1]
The Otis�Lennon School Ability Test (OLSAT), published by the successor of Harcourt Assessment � Pearson Education, Inc., a subsidiary of Pearson PLC � is a test of abstract thinking and reasoning ability of children pre-K to 18. The Otis-Lennon is a group-administered (except preschool), multiple choice, taken with pencil and paper, measures verbal, quantitative, and spatial reasoning ability. The test yields verbal and nonverbal scores, from which a total score is derived, called a School Ability Index (SAI). The SAI is a normalized standard score with a mean of 100 and a standard deviation of 16. With the exception of pre-K, the test is administered in groups.
Uses in education
There are seven different levels of the OLSAT designed for use from kindergarten to 12th grade. The OLSAT serves several purposes: it provides a marker for measuring individual year-to-year progress; some teachers may find it helpful for inferring individual educational needs; and for some school systems, it serves as an economical way to widely assess gifted and talented candidates in the early years.
The Level A OLSAT, the publisher�s lowest level, is designed to assess school abilities of kindergartners (up to a level of "above average"), but it assesses areas that are not universally taught (i.e., it does not assess reading and math abilities). Some educators use the Level A test to assess preschoolers, but, for three-year-olds, require only 40 of the 60 questions. For four-year-olds, all 60 questions are given. Scoring is measured against peers in age groups of 3-month bands. For example, children born October 4 through January 4 are compared with each other and children born January 4 through April 4 with each other and so on.