My 5 yr old son just took a WPPSI-III and the FS IQ is 146 (v 149 p 144). The report says it's a very conservative estimate based on the tester's observation. (I guess it's mainly because he was too tired. somehow he got overexcited the night before and didn't sleep well. he almost felt sleep after one hour test and he didn't want to answer some questions in the later half of the test.) Anyway, I learned that WPPSI-III is capped at 160. But WISC-IV is not. So is there a mapping or projection from the younger children's WPPSI-III score to the older children's WISC-V score? Or it should be the same for the same person, assuming both score were ideally accurate?

Someone who know more will be along in a minute, but I'll have a go. IQs coming from WPPSI and from WISC are intended to be the same - they are both attempts at designing a test to measure the same quantity. WISCIV was originally capped at 160 too; it's only the "extended norms" that allow going higher (and my impression is that although this is official it might be better seen as a bit of fun than real scoring - once you get anywhere close to the ceiling, "beyond measure" is really a better description of the child's IQ than any number).

However, as you say it can make a difference if a child (especially a young one) is tired. This may be particularly the case when a child is being tested close to the age ceiling of the test, because then getting a very high score requires getting almost everything correct - even if you don't encounter actual ceiling effects on subtests (I don't know where they kick in), the test will be in effect less forgiving of slips the older the child is. If you have a subtest breakdown of your DS's score, someone may be able to give you an idea of where, if anywhere, those effects might have been showing up.

Welcome! Was there any particular reason for getting the test done, or anything else you want to talk about?

Thanks for the information. Here is the subtest breakdown:

Verbal:
information 19
vocabulary 18
comprehension 14**
Similarity 17
word reasoning 11**

general language:
perceptive vocabulary 18**
picture naming 16**

performance:
block design 17
matrix reasoning 18
picture concepts 16
picture completion 17**
Object assembly 17**

processing speed:
symbol search 16**
coding 11

verbal IQ 149
Performance IQ 144
processing speed 119
Full Scale IQ 146
General language composite 141

** means the optional test not used in computing FS IQ

For the word reasoning the report says: "He placed at the upper end of the Average range for word reasoning, but he was fatigued during that test and his score was aberrantly low compared to his demonstrated ability on other test."

The coding test is a timed test. It is the second to the last test and I peeked and eavesdropped. This is the one he was really tired and refused to do more and hence "reduced the number of items he completed within the limit".

I have only one question to the test. When I called the tester and asked about the coding score (11) she said it is optional and it's a boring test even for adults. But in the report, the coding shows as a core test. The link below seems to suggest it's optional as well.
http://giftedissues.davidsongifted....3259/New_Here_Q_about_WPPSI_III_sco.html
If that's the case was the FSIQ calculated wrong, or they just marked ** in wrong place but the calculation was correct? Who can tell from the subtest score? Thanks.

To answer you question, I didn't have a particular reason to have him tested. It's his school director pushed for it. We knew he is very smart since he is very young but we didn't want to make it a big deal although we have been a little curious. But in the school all the teachers said he is special. One day the school director (he is in a private kindergarten because of two weeks later than the cutoff date) told us: "you son did my 5th grade son's homework in no time." I was not actually surprised. Then she said why don't you guys have him tested since there are opportunities out there. Then we started to ask ourselves: have we missed something for him? What opportunities are out there? That's why I joined the forum and started this thread.

Thanks Dottie! I didn't "hope" to have a higher score. I was just curious about the 2 aberrantly low 11's and how this contributed to the FSIQ.

I haven't considered any special educational options for him until recently. In the past several years we were often surprised by DS when he naturally developed and demonstrated giftedness but our belief has been that he should live a normal life and grow with children at same age. But since school life is near, textbook is so boring, teachers suggesting, and the doctor strongly recommended skip level and special consideration for his education, now we began to think about it. I really have no idea what DYP, (or other similar programs?) really is and how it works and helps. For now all my plan is to have him enter 1st grade in public school next year and hopefully he can be admitted to their T/G program. They use OLSAT. Is it another type of IQ test, or an achievement test?