The use of word-reading to estimate "premorbid" ability in cognitive domains other than intelligence

Diagnostic neuropsychological assessment requires the clinician to estimate a patient's premorbid abilities. Word reading tests, such as the National Adult Reading Test-Revised (NART-R), provide reasonably accurate estimates of premorbid IQ, but their capacity to benchmark other premorbid cognitive abilities remains unclear. In this extension of an earlier report, we administered the NART-R, an abbreviated Wechsler Adult Intelligence Scale (WAIS-R or WAIS-III), and 26 other cognitive measures to 322 reasonably healthy adults. While NART-R performance correlated robustly (rs ≥ .72) with concurrent Verbal and Full Scale IQ, its correlation with all other cognitive measures was significantly lower. Thus, while it is appealing to use word reading as a proxy for premorbid functioning in other cognitive domains, the NART-R has limited utility for this because it does not predict current performance on other cognitive tests as well as it predicts IQ in healthy adults.