Barona Index is a demographically based regression method to estimate premorbid intelligence in terms of index scores on the Wechsler Adult Intelligence Scale-Revised (WAIS-R).
Attempts have long been made to estimate premorbid intellectual functioning. A frequent method in clinical practice is to estimate the level of premorbid cognitive skill by subjectively considering aspects of the individual’s history such as education and occupation. Another common approach to estimate premorbid IQ is to use tests of present ability, which are thought to be relatively resistant to change even during the phases of a psychiatric disorder or those following a neurologically based disorder. A variant is the best performance method in which the highest score obtained by an individual is assumed to be the most likely premorbid level (Best Performance Method). Research has been inconsistent as to the effectiveness of...