The DAS was standardized on 3,475 children selected to be representative of
non-institutionalized, English-proficient children aged 2 years 6 months through
17 years 11 months living in the United States during the period of data
collection (spring 1987 through spring 1989). Although the DAS standardization
excluded those children with severe disabilities (since for these children the
DAS would be inappropriate), it did include children with mild perceptual,
speech, and motor impairments, if the examiner judged that the impairments did
not prevent the valid administration of the test. The demographic
characteristics used to obtain a stratified sample were age, sex,
race/ethnicity, parental educational level, educational preschool enrollment,
and geographic region. An additional 600 Black and Hispanic children were tested
during standardization to enable accurate analysis of item bias, as well as to
help ensure that item-scoring rules would be sensitive to minority children’s
responses. These additional children were not included in the norms calculation.
For race/ethnicity membership,
individuals were classified as White (N = 2443), African American (N = 525),
Hispanic (N = 382), and Other (N = 125). The four parental
education categories ranged from less than 12 years of education to at least 16
years of education. The four geographic regions sampled were Northeast,
North Central, South, and West. Parents in the White and Other classifications
had the most education—50.8% of the White group and 56.9% of the Other group
had some college education, while 29.2% of the African American group and 19.1%
of the Hispanic group had some college education. The majority of the White and
African American children came from the North Central and South regions, while
the majority of the Hispanic and Other children came from the South and West.
The race/ethnic proportions in the sample were 70.3% White, 15.2% African
American, 11.0% Hispanic, and 3.5% Other. Demographic characteristics were
compared to the March 1988 Current Population Survey of the U.S. Bureau
of the Census and were matched across as well as within categories (i.e., age x
sex x race, age x sex x parent education, age x sex x region, race x region, and
age x race x parent education). Total sample percentages of these categories and
subcategories were very close to the Bureau of the Census data and never
different by more than 0.6 percentage points. There were variations among the 18
age groups.
In the standardization sample, there were 18 age groups: 2:6-2:11, 3:0-3:5,
3:6-3:11, 4:0-4:5, 4:6-4:11, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and 17
years. In each six-month age group between 2years 6 months and 4 years 11months,
there was a total of 175 children, while from ages 5 through 17 there were 200
children in each one-year age group. In each six-month age group between 2 years
6 months and 4 years 11months, there were approximately equal numbers of males
and females, while for all remaining age groups there were 100 males and 100
females per group. This sampling methodology was excellent. Small (under
100,000) and large (over 1,000,000) communities were slightly underrepresented.