ABILITY TESTS assess cognitive and motor skill sets that have been acquired over a long period of time and that are not attributable to any specific program of instruction. Ability tests are descriptive in that they assess people’s knowledge and skills, but they are also predictive because they measure qualities that are presumed to influence the person’s ability to learn new skills and to solve novel problems.
Examples:
Wechsler Adult Intelligence Scale—Third Edition (WAIS-III)
Stanford-Binet Intelligence Scales, Fifth Edition (SB5)
Cognitive Abilities Test (CogAT)
ACHIEVEMENT TESTS are descriptive - to measure the extent to which an examinee has mastered a motor skill or area of knowledge. Typically, an achievement test is administered following a period of instruction designed to teach the motor or cognitive skill to be examined.
Examples:
ACT
SAT
Classroom examinations
State tests
APTITUDE TESTS often attempt to measure certain abilities that a person may possess, such as verbal or numerical skills. Aptitude tests typically reveal what sort of tasks a person may be best able to perform regardless of any previous course of study in that area. The primary purpose of aptitude tests is prediction. In fact, the most common use of aptitude tests is to predict future performance in an educational program or occupational setting.
Examples:
Armed Services Vocational Aptitude Battery (ASVAB)
Ball Aptitude Battery (BAB)
In summary, psychologists distinguish among achievement, aptitude, and ability tests at a theoretical level. Achievement tests describe people’s present status, aptitude tests predict their future behavior, and ability tests assess their innate potential.