This study examines the utility of the American version of the National Adult Reading Test (AMNART) as a measure of premorbid intelligence for older adults. In a sample of 130 older adults, aged 56 to 104, the AMNART was compared to other tests of premorbid intelligence. The results revealed that AMNART-estimated IQ was significantly higher than other premorbid estimates. Across specific educational groups (i.e., 0–12, 13–16, and 17 or more years of education), AMNART-estimated IQ was inflated relative to all other premorbid estimates. The AMNART also declined as cognitive impairment increased, and there was a significant interaction between aging-related diagnostic group and premorbid estimate. The AMNART may therefore overestimate premorbid ability relative to other premorbid measures, particularly among those with greater cognitive impairment and lower levels of education. These results suggest that the AMNART should be used cautiously among older adults and in conjunction with other estimates of premorbid ability. 1. Estimating Premorbid Intelligence among Older Adults: The Utility of the AMNART Considering the rapidly burgeoning older population, increased attention is being given to an accurate assessment of older adults’ cognitive and neuropsychological functioning. Part of this process involves obtaining a viable estimate of their premorbid cognitive ability or their expected performance prior to any injury or relative decline in cognitive functioning. These premorbid estimates are critical toward determining the nature, type, and severity of cognitive impairment. It is vital when estimating the level of cognitive decline to account for variations in premorbid ability. For example, an older adult might be performing in the average range relative to his or her peers, but this could be a potential decline if his or her previous premorbid abilities were in the high average or superior range. It is also important to obtain a premorbid indicator in addition to age-based norms to account for other factors, such as formal education and occupation, that can contribute to one’s intellectual abilities. To this end, various approaches have been developed to estimate premorbid intelligence. One approach to assessing premorbid functioning among older adults involves the use of demographic variables, such as education, sex, handedness, and occupation [1]. This approach can be useful because the data are gained without lengthy or invasive testing and independent of the patient’s current cognitive functioning and therefore remain constant throughout the
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