Validity refers to the degree to which a measurement accurately reflects what it is intended to measure. For example, if the Korean-Wechsler Intelligence Scale for Children (K-WISC) is used to assess intelligence in a child with a disability who has significant difficulties in verbal expression, the test might inaccurately yield a low score, even though the child may actually possess high intelligence. In such a case, the validity of using the K-WISC for this particular child would be considered low. A more appropriate tool, such as the Korean-Pictorial Test of Intelligence (K-PTI), which does not rely heavily on verbal communication, would better reflect the child’s intellectual ability, thereby offering higher validity.