The original Leiter International Performance Scale, based on studies of children in Hawaii, was developed by Russell Leiter in 1929. Its purpose was to assess the abilities of children who had difficulty responding verbally. The current edition is the first revision of the Leiter since 1948.
Description of the Test
The Leiter-Revised (1995, 1997) assesses cognition in individuals ranging in age from 2 years 0 months through 20 years 11 months. It was specifically developed for examinees with communication disorders, hearing and motor impairments, traumatic brain injuries, attentional problems, and learning disabilities. Individuals who are not proficient in English are also good candidates for use of this measure.
Authors of the current edition reported that their work was guided by models of cognitive ability developed by Gustafsson (1984) andCarroll (1993). They have conceptualized nonverbal cognitive abilities in terms of various mental functions, such as reasoning, visualization, memory, and attention. The authors emphasized that nonverbal cognitive abilities are not solely dependent on proficiency in the use of printed materials, words, and numbers. Therefore, administration of the Leiter-R is accomplished through the use of pictures, figures, and symbols. Instructions are delivered in a nonverbal format, using gestures and pantomime.
The Leiter is divided into two groups of ten subtests each. Subtests from the Visualization and Reasoning Battery (VR) (i.e.