GRS is among the top-tier of such rating scales meant to be used for gifted and talented identification, it is also by far the most expensive. 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. Rating scales, in general, can be subject to rater bias based upon the characteristics of the rater. This is of particular concern for children being evaluated for kindergarten because the credentials of the raters from preschools greatly vary. Slight changes in the wording of instructions, or the wording of the items themselves, may have a significant effect on the child's response. Data obtained from ratings rely totally on the rater's familiarity with the child. In practice, the rater of a preschooler, for example, may not be the same person that spends time with the child. Rating scales, in general, are limited to the informant's perspective. Information that may be relevant to the subject, but that is not covered by the items of the scale will be missed. With rating scales, it is not possible to explore the informant's responses and subjective experiences, nor is it possible to observe behavior directly. 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. It also removes the assessment duties from the erstwhile used tightly controlled NYC DOE process that uses pre-approved, independent child psychologists (who had, until 2007, administered the Stanford Binet), and gives most of the duties, instead, to a publishing company and laypeople. IQ in the top 5% is difficult to accurately measure. The GRS is too new to have been adequately normed for acceptable accuracy at those levels. Criteria, such as Leadership and Motivation, are often counter-correlated with high IQ, so the GRS might actually