Differential Ability Scales (DAS)

The differential ability scales (DAS) is normed in the US and individually administered battery of cognitive and achievement tests. The test can be administered to children ages 2 years 6 months to 17 years 11 months across a range of developmental levels.

The diagnostic subtests measure a variety of cognitive abilities including verbal and visual working memory, immediate and delayed recall, visual recognition and matching, processing and naming speed, phonological processing, and understanding of basic number concepts.

The original DAS was developed from the BAS (British Ability Scales) both by Collin D. Elliot and published by Harcourt Assessment in 1990.

The DAS-II consists of 20 cognitive subtests which include 17 subtests from the original DAS. The subtests are grouped in to the early years and school age cognitive batteries (Array/Group) with subtests that are common to both batteries and those that are unique to each battery. These batteries provide the General Conceptual Ability (GCA) score, which a composite score is focusing on reasoning and conceptual abilities.

The early years core battery includes verbal, nonverbal and spatial reasoning subtest appropriate for ages 2 years 6 months to 6 years 11 months. There are three optional diagnostic subtests – Recall of Objects Immediate and Delayed, Recall of Digits Forward and Recognition of Pictures. There are also two optional diagnostic clusters: Working memory and processing speed.

School age core battery contains subtest that can be used to asses children ages 7 years to 17 years 11 months. These subtests measure verbal, nonverbal reasoning and spatial reasoning abilities. The subtests can also be used to assess children age 5 years to 6 years 11 months who may be cognitively gifted. In addition there are up to 9 diagnostic subtests for this age group that fits into three possible diagnostic cluster scores: Working memory, Processing Speed and for the young ages, school readiness.