Why was a third task—Digit Span Sequencing—added to the Digit Span subtest?
Digit Span Sequencing was added to increase the working memory demands of the Digit Span subtest relative to the previous version, in response to research indicating different cognitive demands for the Digit Span Forward and Digit Span Backward tasks. The total raw score for Digit Span is now based on Digit Span Forward, Digit Span Backward, and Digit Span Sequencing. Digit Span Forward must be administered, as pilot study data indicated the omission of this task results in lower Digit Span Backward scores for some examinees (possibly due to the loss of instructional progression). Retaining Digit Span Forward also ensures sufficient floor items for examinees with intellectual disability or general intellectual deficiency. The separate process scores for each of the three tasks allow practitioners to evaluate differential performance across the tasks.
