Term used in assessment.

Basal age is the age at which a child can answer all the questions on a specific standardized test correctly and consistently. Sometimes referred to in discussions as simply the "basal," this term is used by psychologists to establish the appropriate testing level for a child. Until the psychologist establishes a child's basal age, it is difficult to begin meaningful testing, especially for children whose performance deviates significantly from the average. The opposite of basal age is ceiling age, the age at which a child fails to answer any item on a standardized test correctly.