Gifted Issues Discussion homepage Forums Identification, Testing & Assessment How can I calculate GAI for WPPSI-IV?

We are thinking about applying for DYS for my DS5. His full scale is 144 which is not qualified. He is strong in block design, matrix reasoning, fluid concepts while relatively weaker in verbal and did not do well in processing speed test: cancellation. Our WPPSI-IV report did not provide GAI or non-verbal score which DYS require. Are there any ways to calculate GAI or non-verbal score for WPPSI-IV? I saw an online doc which shows instructions to calculate GAI for WISC-IV: Add the sum of scales for vocabulary, comprehension, similarity, block design, matrix reasoning, fluid concepts, and compare it to a table. Is it the same for WPPSI-IV? My son's sum of scales for the six items is 101. DYS also allows a non-verbal score. How is non verbal score calculated? Does it refer to the result of block design, matrix reasoning, fluid concepts? Thanks a lot.

The Nonverbal Ability Index is derived from the scaled scores of the two Fluid Reasoning subtests (matrix reasoning and picture concepts), and one subtest apiece from the other nonverbal clusters: from Visual Spatial, block design, from Working Memory, picture memory, from Processing Speed, bug search.

The GAI is derived from the two Verbal Comprehension subtests (information, similarities), and one each from Visual Spatial (block design) and Fluid Reasoning (matrix reasoning).

The tables for both of them are in the WPPSI-IV manual, which your examiner has. If you want a report for DYS, then you will need to go back to your examiner and get those additional Index scores included in your formal report.

Do you have all five primary index scores? Verbal Comprehension, Visual Spatial, Fluid Reasoning, Working Memory, Processing Speed. What were his Index scores like? If his VCI was weaker (from what you are saying), then his GAI is unlikely to be significantly higher than his FSIQ, and will probably be lower, as half of the subtests that comprise the GAI are verbal, versus one-third of the subtests being verbal on the FSIQ. He might have a better chance with the NAI, as that uses bug search instead of cancellation.

Can a GAI be calculated if the under 4 version of the WPPSI-IV was given?

My DS had a VCI > 150 (hit the ceiling) and his lowest scores were performance related - so I am wondering if the GAI (if it can be generated by our examiner) might meet the threshold.

Yes. It consists of the four core subtests in the VCI and VSI. Norms are in the standard manual, accessible to your examiner. Also out there somewhere are extended norms under development for the WPPSI-IV. I haven't seen them yet, but Pearson's people claim that someone is working on them.

Thanks a lot for the detailed description. I think we should have better chance with Non-Verbal. Our examiner only provided VCI 129, Fluid Reasoning 145, FSIQ: 144. She did not respond to our email after we received our report. We were frustrated.
His scores are:
information: 17
Vocabulary:17
similarity: 13

block design:19

matrix reasoning: 18
picture concepts: 17

picture memory 16

bug search 17
cancellation: 9

Do you think we have a chance assuming we could find her to obtain the non-verbal score?

Thanks a lot!

Yes, I think you do. His performance overall on the Nonverbal subtests is more similar to his performance on the Fluid Reasoning subtests than it is to his verbal performance. Especially since bug search is supposed to be the subtest used in the composite, rather than cancellation.

I should mention that that is a rather dramatic difference between the two PSI subtests. Did your DS or examiner make any comment about that?

We were wondering about the difference when we got the report. My son only said it was fun. The examiner did not provide additional information other than 9=37% and did not reply our email inquiry. Now it seems that I should make more effort to find her.

Thanks a lot for your help.

Did you pay yet? And what did you contract her to do?

We paid right after the test was taken and before we got the report which was in Jan. We did the test as the application to the private school required it. We were not very educated. The examiner said "the fee covers the testing, scoring the test, a four or five page report which is sent to you and with permission will be sent to any schools you indicate. In addition, I am available to answer any questions you might have about the testing." We were not very specific regarding what index should be provided in the report. We emailed her with our question right after we got the report but she was not replying.