Basal Level and Ceiling Level

The basal level (also called the floor level) and the ceiling level are components of the termination criteria used in Binet-type individually administered adaptive tests that are used to measure IQ in educational and other settings. These tests are administered by psychologists or trained examiners and operate from a question/item bank that is organized into mental age levels. Mental age is defined for each test item as the average chronological age at which approximately 50% of the standardization examinees correctly answered the item.

The adaptive test is begun by the examiner by selecting a mental age level based on the examiner’s knowledge of the child being tested. This information can simply be the child’s chronological age or can be based on other information such as a ...