1 European Journal of Psychological Assessment, Vol. 9, 1993, Issue 2, pp. 147-157 (the published text is a slightly abbreviated form of the text presented here) ---------------------------------------------------------------------------------------------------- The Construction and Validation of a Nonverbal Test of Intelligence: The revision of the Snijders-Oomen tests Peter Tellegen & Jacob Arie Laros Personality and Educational Psychology, University of Groningen, The Netherlands. Keywords: nonverbal intelligence test, test construction, cross-cultural testing, culture-fair test, language-free test. For fair intelligence assessment of children of ethnic minorities and of children with hearing, speech and language problems nonverbal tests are generally indicated. For this purpose the Snijders-Oomen tests have been used since 1943. With these tests a broad spectrum of intelligence can be examined without the use of receptive or expressive language. The latest revision, here described, incorporates new features of test construction, adaptive testing, establishing of norms and estimation of ability. A summary is given of research findings related to the structure of the test, the reliability, and the validity with hearing and deaf children. Introduction Intelligence assessment is probably the most widely used tool for the psychological diagnostic evaluation of children, with far reaching consequences for schooling, referral to special programs, and treatment of specific handicaps. Although there are good tests for general intelligence like the Wechsler scales, their dependency on language skills in test contents and instructions makes them less appropriate for the assessment of cognitive abilities of ethnic minorities and of children with problems with verbal communication, such as deaf and hearing disabled children and children with speech and language disorders. For these groups, low performance on a general intelligence test might primarily reflect poor verbal knowledge instead of limited reasoning and learning ability. Nonverbal tests for intelligence assessment like the Raven's Progressive Matrices (Raven, Court & Raven, 1983) and the TONI (Test Of Nonverbal Intelligence; Brown, Sherbenou & Johnsen, 1990) are unidimensional tests with very specific contents which do not allow generalizations to a broad area of intelligence. Because of this they are not attractive alternatives for multi-trait multi-method tests like the WISC-R (Wechsler, 1974).