AMNART and RIST Differences Across Groups with MCI, Dementia, and Normal Individuals

Objective: Brief measures of intelligence are often used in dementia evaluations to estimate an individual's current and/or baseline abilities. A comparison of two such measures, the Reynolds Intelligence Screening Test (RIST) and the American version of the Nelson Adult Reading Test (AMNART) across various patient groups is presented. Method: One hundred and twenty-six of 181 patients from a memory disorder clinic who were consecutively referred for neuropsychological evaluation and met study criteria (valid test effort and the ability to establish a consensus diagnosis of normal aging, Mild Cognitive Impairment [MCI], or dementia between the referring neurologist and neuropsychologist based on all available examinations and diagnostic studies) were included. Scores for the AMNART and RIST were compared across the three groups. Results: AMNART results were not different across the three groups. RIST scores, in contrast, were significantly different between normal, those with MCI, and those with dementia. These results were seen for not only the Total score but also the subtests consisting of Guess What and Odd Item Out, suggesting that all three indices are able to detect cognitive decline. Conclusion: Two brief intelligence estimates function differently with individuals who have MCI and dementia. The AMNART appears to be a classic measure of prior word knowledge and is relatively resistant to early dementia. The RIST is a strong indicator of current intellectual abilities, as it taps aspects of long-term memory, semantic ability, and visual reasoning that can be affected by early cognitive changes. Further uses and the limitations of both measures are discussed.