Here is the infomration from the Use of the SB5 in the Assessment
of High Abilities Bulletin:
Analysis of the case studies reveals that a rather surprising number of the exceptionally gifted�and boys in particular�score lower on Knowledge (KN), and especially Verbal KN (Vocabulary), than on the other factors. Although merely speculative at this stage, it may be fruitful to investigate whether or not video
game or computer use might have cut into the reading time of the generation(particularly boys) now in school. Tyler is actually well read and factually knowledgeable, but his immediate grasp of out-of-context vocabulary was relatively low for his overall ability. The report includes this explanation:
Knowledge represents an examinee�s accumulated fund of general information acquired at home, school, or work. In research, this factor has often been called crystallized ability. Although still above average, the Knowledge factor score was relatively lower than his other factor scores. Additionally, the Verbal
Knowledge subtest Vocabulary contributes half of the score to the Abbreviated Battery IQ (ABIQ), explaining his relatively lower ABIQ of 130 (that is, lower relative to his FSIQ).
