Gifted Issues Discussion homepage Forums Twice Exceptional interpret low digit span score on WISC IV

Irena-- Interesting. My son is "high avg" for digit span which is low comparatively but miles above both our PSI subtests. (His working memory is only a tad over one SD below his VCI.) This despite his very clear ADHD profile and diagnosis as well as his Dyspraxia. I usually find your son right in line with mine so I find this difference curious and wonder what is the functional difference between them that creates that variance. It's got my curiosity working. Thanks for sharing this.

I have no idea either, unfortunately ... it seems difficult to find info on the digit span test and the different cognitive processes involved and what the test means.

My DS's WM is superior now so I am really befuddled. When he was last evaluated it came up as superior on the WISC IV but I just realized I do not know the breakdown of how he did on numbers reversed and forward. I do remember at 6 DS could usually do 3 numbers backwards but he did struggle with 4 backwards...

Well, it seems our sons are back in line with each other again b/c my son's didgit span test was high average on his most recent WISC IV (I posted my original post on this thread before DS was last evaluated). I am in shock by his "above average" digit span and his "superior" workling memory ... I still sometimes wonder if they confused him with someone else LOL

Hi, im relatively new to this. I am wondering how do you interpret digit-span results on the WAIS. For example, say someone got an 8 - is there any way i can correlate that to the capacity of numbers they recalled correctly? Does any (adult) have any empirical evidence they can share with me?

From the very brief reading I've done on digit span, the average adult has a forward digit span of about 7 (give or take 1 or 2). So that's like remembering a phone number. I don't know what a score test of "8" would be, other than it's probably in the low average range. So maybe they remembered 5 or 6 digits. Just guessing.

My son got a "7" on digit span the first time he took the WISC IV at 6 1/2 years. I remember that he seemed to do okay on numbers forward but really poorly on numbers backward. But I do not know how many he got right. The score is 'scaled' so basically you get like two points for each right answer, it's totaled (I think that is the "raw score"), and, then, the tester looks the raw score up on a chart by age for the scaled score.... so it's sort of hard to figure out.

Take heart my kid's digit span score and letter number sequencing score improved significantly over a year and half...

Ahh ok. Thanks guys. This is interesting because i am pondering as to what would give you (adult per say) a 99% percentile digit span score. Something along the lines as to how many correct. Quite possibly someone here has an empirical experience of getting a really high score and X # of digits recalled

Remember this very recent thread on digit span (some useful likes within it)...

http://giftedissues.davidsongifted....h/true/Digit_span_scores.html#Post183527

There is indeed nothing to worry about; a test's "g-loading" is its correlation with full-scale IQ (the extent to which the test taps into the general intelligence factor). Forward digit-span only has a g-loading of about 0.30, meaning that only 9% of the variance in scores on forward digit-span are attributable to differences in g. There is no reason to assume that because a child has a high IQ, such as your son, that he or she would perform in the superior range on forward digit-span.

Backward digit-span is a much more g-loaded task, with a correlation with full-scale IQ of about 0.40 (i.e., 16% of the variance in performance on backward digit-span is attributable to full-scale IQ). However, a person's performance on this task is hindered by his or her forward digit-span; in other words, a child cannot recall a certain number of digits backwards if he or she cannot first recall the digits forward. (There are of course exceptions to this rule, and they reveal valuable clinical information on the momentary psychological and physiological state of the examinee).

When one combines the forward digit-span and backward digit-span tasks, one yields the digit span task utilized on the WISC-IV and WAIS-III, which has a g-loading of about 0.57 (about 32% of the variance on this task is explained by differences in g). This is still a fairly poor g-loading. In a sample of 148 gifted children, the average group performance on digit span was 13.5, with a maximum of 21 and a minimum of 6. In comparison, the group's average performance on vocabulary was 16.1, with a minimum of 12 and a maximum of 28. (Vocabulary has a g-loading of 0.83).

In conclusion, the results are not at all inconsistent; a very high IQ in no way mandates very superior or even superior performance on the digit-span task because it is a poorly g-loaded test.