Change in Verbal IQ between initial testing and follow-up testing. The horizontal axis depicts testing intervals reflecting time from diagnosis to initial testing, first data point, and time from diagnosis to follow-up testing, second data point. The vertical axis depicts age-adjusted Verbal IQ scores (expected mean, 100; SD, 15), with age identified at time of respective testing. The top box (A) clusters the 49 survivors (black lines) and group average (red line) of those who did not demonstrate a decline in Verbal IQ from initial to follow-up testing, whereas the bottom graph (B) clusters the 53 survivors who demonstrated at least a 10-point decline in Verbal IQ between the 2 testing sessions. Of note, very few survivors demonstrated an increase in Verbal IQ from initial to follow-up testing (A).