Estimating WAIS IQ from the Shipley Institute of Living Scale: a replication

This study represents a replication of the linear regression techniques and continuous norming used to estimate age-adjusted WAIS IQ from the Shipley Institute of Living Scale. The sample was composed of 125 male, right-handed, psychiatric patients, who represented five age decades between 20 and 70. The overall correlation coefficient between observed and estimated IQs was .79. The data suggest that the prediction formula is robust across all five age groups. The data also show the Shipley estimated WAIS Full Scale IQ to be somewhat better when compared with the continuously normed WAIS IQ than when compared with the WAIS tabled norms. Thus, the present results provide support for the utility of the continuous norming procedure for predicting WAIS IQ from the Shipley and argue for its use.