Relationships between the WAIS and neuropsychological measures for neuropsychiatric inpatients

The current study examines the sensitivity of the Wechsler Adult Intelligence Scale in predicting performance on a modified Halstead Neuropsychological Test Battery for lower-functioning neuropsychiatric inpatients (97 men, 54 women). Regression analyses support earlier-reported findings that the WAIS's subtests more accurately predict neuropsychological test performance than do the WAIS IQ's alone. The IQ's and scaled scores respectively predicted 27% and 39% of the variance in the Halstead's measures. The overall relationship between neurocognitive and WAIS indices is somewhat greater than previous reports and is apparently due to the fact that the lower the overall level of cognitive ability, the lower is neuropsychological functioning in general. However, since most of the variance in the modified Halstead Battery was not common with the WAIS's indices, these findings continue to support the practice of including both sets of measures as part of a comprehensive neuropsychological assessment paradigm for such patients. The importance of developing instruments and procedures which more precisely measure "fluid" neurocognitive abilities is underscored.