Interested persons should consult the Buros Mental Measurement Yearbook review of the GRS for additional information on this and other rating scales.
The GRS as a rating scale has yet to be evaluated up to the level commonly accepted by major research associations (NCTM, AERA, APA).
The GRS assessment is controversial because, among other things, intellectually gifted children at the highest levels are often not "teacher pleasers" and can be misunderstood or evaluated with prejudice, especially by laypeople with no expertise in giftedness.
Moreover, raters can't access, guess, or factor for certain likable or unlikable characteristics such as hyperactivity or inattention or aggressive/stubbornness.
Because the GRS is administered by laypeople, critics aver that in a large school system, such as New York City, problems with measurement consistency can be tolerably contained within Regions; but it can be injurious to students wrongly admitted to more rigorous citywide schools for intellectually gifted.
In the case of the New York City public schools, the implementation of the GRS and the OLSAT, together, essentially represent a shift away from using IQ as the prime criteria for identifying special needs.
Criteria, such as Leadership and Motivation, are often counter-correlated with high IQ, so the GRS might actually screen out children who most need special attention.