Profile analysis of the Wechsler intelligence scales: a new index of subtest scatter.

A statistical method of profile analysis originally suggested by Huba (1985, 1986), the Mahalanobis distance, D2, is described and discussed with reference to its use with the Wechsler scales. Examples are given to illustrate the properties of D2 and two BASIC computer programs are presented that will calculate D2; one for the WAIS-R and the other which can be readily adapted to the test selection of the user's choice. It is argued that D2 is a useful addition to existing methods of statistical analysis of the Wechsler scales.