A CogAT percentile rank shows the percentage of students in the comparison group who scored at or below a student’s score.
How CogAT percentiles work
A percentile rank of 90 means the student scored as well as or better than approximately 90 percent of students in the stated norm group. It does not mean the student answered 90 percent of the questions correctly.
50th percentile
Near the middle of the norm group.
90th percentile
Higher than approximately nine out of ten students in the norm group.
99th percentile
At or above approximately 99 percent of the norm group; the top percentile still contains a range of scores.
Why percentile gaps can be misleading
Percentiles are ranks, not equal units. A change of five percentile points near the middle does not necessarily represent the same score difference as five points near the top. Use SAS values and confidence information when available for more careful comparisons.
Age percentile or grade percentile?
Age percentiles compare students of similar ages. Grade percentiles compare students in the same grade. The two values may differ, especially for students who are young or old for their grade. Never interpret a percentile without checking its label.
For placement questions, read what CogAT score may qualify as gifted.
Local policy controls: A high percentile can be important evidence, but it does not create a universal entitlement to gifted placement.