The Snijders-Oomen nonverbal intelligence tests, shortly the SON-tests, are intelligence tests appropriate for children and adults from two and a half to forty years old. The tests are called nonverbal because they can be administered without having to use written or spoken language. The manuals also contain verbal instructions, but the spoken text does not contain extra information compared to the non-verbal instructions. The way the tests are administered is adjusted to the communicative abilities of the subject in order to create a natural test situation. The tests provide an intelligence score that indicates how someone performs in comparison with other persons from the same age.
HistoryopG
The first version of the SON test was developed more than seventy years ago by psychologist Nan Snijders-Oomen, to study the cognitive functioning of deaf children. The goal of this test series was to break the one-sidedness of the non-verbal performance tests of that time and to broaden the functions accessible for non-verbal intelligence research. The first revision of the test was published in 1958 by Dr. Nan Snijders-Oomen and her husband, professor of Psychology Jan Snijders. This test series included norms for both hearing and deaf children. The original SON needed a transition to another type of items for children of about six years. This led to the second revision in 1975 where the test was divided into the SSON for children of seven to seventeen years old and the SON 2.5-7 for children up to seven years old. The next revisions were published under the responsibility of psychologists Peter Tellegen and Jaap Laros from the university of Groningen. The SON-R 5,5-17 was published in 1988. This test replaced the SON-’58 and the SSON. Subsequently, the SON 2.5-7 was revised, which resulted in the publication of the SON-R 2,5-7 in 1998. A short version of this test was published in 2007, the SON-R 2,5-7 [a], which is designed to be administered in non-western countries. Finally, the SON-R 6-40 was published in 2011 as a revision of the SON-R 5,5-17. This test is appropriate for both children and adults.
Test format
SON-R 2,5-7
The SON-R 2,5-7 consists of six subtests that contain series of fourteen to seventeen items with increasing difficulty. The testing procedure is adaptive in order to limit the test time and to prevent giving children items that are far beneath or above their level. Entry and stopping rules are used to determine where the test should be started and discontinued. The test administrator provides the test subject with feedback after every item; indicating if an answer is right or wrong and demonstrates the solution to an item if a wrong answer was given. This way, children are given the possibility to learn and correct themselves. The subtests exist of performance and reasoning tests. The performance tests involve producing a solution while working on an item. The reasoning tests are based on discovering relationships between concepts or objects. Mosaics This subtest is a spatial visualization test. With this test, children have to copy a certain mosaic pattern with square pieces in a framework. Categories This subtest measures abstract reasoning ability. Cards have to be sorted or cards have to be selected on basis of categories. Puzzles This is a concrete reasoning test. First, children have to recreate example pictures with puzzle pieces and later on in the test, they have to form pictures on their own without an example. Analogies This subtest measures abstract reasoning ability. In the first part of this test, children have to discover the sorting principle of an example and sort pieces according to this principle. In the second part, children have to understand the principle of change of an analogy and solve another analogy via this principle. Situations' This subtest is a concrete reasoning test. Here, children are required to complete half-finished drawings by matching the missing parts. The next part consists of choosing the missing parts out of a few alternatives, to create a logically coherent picture. Patterns This subtest measures spatial visualization ability. In this subtest, children have to copy certain example patterns.