The Symbol Digit Modalities Test: a screening instrument for brain-damaged children.

28 brain-damaged males ranging in age from 8 to 16 yr. were compared with 28 nondamaged matching controls on their Symbol Digit Modalities Test performance. The damaged group performed significantly more poorly, and 75% of the subjects scored more than .5 z score below their matched controls. The results suggest that this brief and objective test can be used to screen brain-damaged children when their performance is compared to that of a control group or the normative group.