Holland T R, Levi M, Watson C G
J Clin Psychol. 1981 Apr;37(2):394-6.
Made comparisons between MMPI basic scales and two-point codes in the discrimination of brain-damaged, schizophrenic, neurotic, and alcoholic patients (N = 380). Although levels of group differentiation were relatively low for both scales and codes, the latter approach was seen to result in a considerable loss of information and a concomitant reduction in criterion-related validity.