Koegel, L. K., Koegel, R. L., & Smith, A. (1997). Variables related to differences in standardized test outcomes for children with autism . Journal of Autism and Developmental Disorders , 27 (3), 233–243. https://doi.org/10.1023/A:1025894213424

Two different testing conditions were employed: the standardized condition and a motivation/attention condition. In both conditions, the examiners verbally encouraged the children and provided verbal and edible rewards contingent upon appropriate test-taking behavior.

A total of 6 children who were either preschool-aged or elementary school-aged, five boys and one girl, participated. All were diagnosed with autism. The children's ages ranged from 3 years, 1 month to 9 years, 6 months.

Four standardized language and intelligence tests were given: Assessment of Children's Language Comprehension (ACLC; Foster, Giddan, & Stark, 1973) Multiple Components Test Section; ACLC Vocabulary Test Section; Peabody Picture Vocabulary Test-Revised (PPVT-R; Dunn & Dunn, 1981); Intelligence Tests.

With only one exception, the test scores for the 44 separate testing sessions were always higher in the motivation/attention condition. The higher test scores under the motivation/attention condition were evident for receptive vocabulary tests, receptive language tests, verbal intelligence tests, and nonverbal intelligence tests. Three children, unable to reach a measurable standard score under the standardized test condition, were sometimes able to score in the normal range when the motivation/attention techniques were implemented.