Prediction of WAIS IQ with the National Adult Reading Test: Cross‐validation and extension

Abstract

Nelson (1982) presented regression equations for the prediction of Wechsler Adult Intelligence Scale (WAIS) IQ from performance on the National Adult Reading Test (NART). In a cross‐validation sample (n = 151) these equations predicted 66, 72 and 33 per cent of the variance in WAIS Full Scale, Verbal and Performance IQ respectively. There were no ceiling or floor effects in the relationship between NART performance and WAIS IQ despite the wide IQ range of the sample. The standardization and cross‐validation samples were combined (n = 271) to generate new regression equations. These equations should be used in preference to the original equations as they are based on a larger sample with a wider IQ and age range. Combining NART and Schonell Graded Word Reading Test errors did not improve IQ prediction in poor readers. A detailed examination of the NART's test—retest and inter‐rater reliability was also conducted.

Do reading tests measure the same construct in multiethnic and multilingual older persons?

“…It is possible that reading scores in participants with dementia lowered the mean scores in our sample (Patterson et al, 1994;Storandt et al, 1995;Taylor et al, 1996); however, the vast majority of dementia cases in our sample were mild (13 of 14), and many studies have suggested that single word reading is preserved in early dementia (Crawford et al, 1989;Del Ser et al, 1997;Hart et al, 1986;Nelson & O'Connell, 1978;O'Carroll & Gilleard, 1986;Sharpe & O'Carroll, 1991). Importantly, the proportion of individuals with dementia in our sample did not differ by ethnicity or language, suggesting that any potential effect of cognitive impairment on the current data would not vary across group.…”

“…Further, prior studies of the WAT (Del Ser et al, 1997) and NART (Crawford et al, 1989;Nelson & O'Connell, 1978) have demonstrated comparable reading scores across healthy controls and patients with mild AD, and such scores have been shown to remain stable over time in the context of cognitive decline associated with mild AD (Hart et al, 1986;O'Carroll & Gilleard, 1986;Sharpe & O'Carroll, 1991). However, to be sure that the presence of dementia in one group did not systematically bias our findings, we analyzed the proportion of individuals with this diagnosis across ethnic and language group.…”

“…Scores on both English and Spanish single word reading tests have been shown to correlate with traditional measures of intellectual functioning and years of education in cognitively healthy elders (Crawford et al, 1989;Del Ser et al, 1997;Grober & Sliwinski, 1991), and are believed to represent similar constructs across English and Spanish speakers. However, there are methodological hurdles to combining multilingual reading scores in a single analysis for use in a cross-cultural sample.…”

Cognitive functioning after adjuvant chemotherapy and/or radiotherapy for early‐stage breast carcinoma

“…Before analysis, test scores were converted into Tscores (mean of 50 and a standard deviation [SD] of 10) that were age-corrected for the WAIS-III and WMS-III measures, 18,20 and age-and education-corrected for the CVLT, 17 Trail Making, 25 Finger Oscillation Test, 19 and COWA. 21 A total neuropsychologic score was created by averaging performance across all measures.…”

“…Previous studies have shown that performance on the NART is highly correlated with general intelligence (factor 'g') as measured by the Wechsler intelligence scales. 18 Accordingly, NART was included to estimate overall intellectual ability and was not combined with scores from the other cognitive measures.…”