Gifted Issues Discussion homepage Forums Identification, Testing & Assessment Statistical significance/rarity

Is there a way to calculate or determine the statistical significance or rarity of certain WISC index results (profiles) without the raw score?

Were you give IQ's or ranges of IQ's and you're trying to figure out percentiles from those? Or something else?

Yes. If you let me know what the WISC (specify -IV or -V) index scores are, I can look them up. There are tables for statistical significance of the difference between index scores, and base rates of the magnitude of the difference. Generally, the rule of thumb for clinical significance is both statistical significance at at least the .05 level (I prefer .01), and also a base rate of less than 10%.

I have assumed that you are talking about index profiles, or the diversity/range of a group of index scores. If you are referring to the significance/rarity of individual index scores, that information is captured by the percentile.

Yes, this one.

I think she has a unique profile between index scores so I'm curious if they are statistically rare or significant in testing results.

I can message them to you. Thank you again aeh! I don't know what this forum would do without you.

aeh - If I message you DS's index scores, could you do this for DS as well? This could be extremely useful for our upcoming SST meeting.

If you can - do you need index scores with extended norms or without?

Thanks,
Sue

P.S. Apologies for barging into this thread!

Certainly, sue.

Send me both standard and extended, and I'll see which one makes more sense on the tables. (Most likely standard, but since what we're looking at is difference scores, the extended might be informative as well.)

Barge ahead!

thank you!