Index-based short-form of the WAIS-III with accompanying analysis of reliability and abnormality of differences


The National Adult Reading Test (NART) is widely used to estimate premorbid ability in clinical neuropsychology. However, there is accumulating evidence that NART performance can be impaired in some neurological disorders. This program implements a multiple regression equation that can be used to predict an individual's NART performance from demographic variables (age, sex, years of education, and occupational code). The demographic estimate of NART performance is compared with the obtained score to evaluate the likelihood that the NART will provide a valid estimate of premorbid ability. The equation was built in a healthy UK sample (N= 659).

To download the computer program (NARTVAL.EXE) click here. For essential background information see the following paper:

Crawford, J. R., Allan, K. M., Cochrane, R. H. B. & Parker, D. M. (1990). Assessing the validity of NART estimated premorbid IQs in the individual case. British Journal of Clinical Psychology, 29, 435-436.

reprint as pdf

Although primarily designed for use in clinical practice with individuals, the equation can also be used in research studies to evaluate whether NART performance "holds" in specific neuropsychiatric disorders. For an example of this use see the following paper:

O'Carroll, R. E., Moffoot, A., Ebmeier, K. P., & Goodwin, G. M. (1992). Estimating pre-morbid intellectual ability in the Alcoholic Korsakoff Syndrome. Psychological Medicine, 22, 903-909.

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Once downloaded, the programs can be run by any of the normal Windows procedures i.e. by clicking on file in File Manager or by placing on desktop etc.

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The author of this software (John R Crawford) and the University of Aberdeen make no representations about the suitability of the software or about any content or information made accessible by the software, for any purpose.

The software is provided 'as is' without express or implied warranties, including warranties of merchantability and fitness for a particular purpose or noninfringement.

The software is provided gratuitously and, accordingly, the author shall not be liable under any theory or any damages suffered by you or any user of the software.

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