Abstract
Derived indices on the Trail Making Test (TMT), a test often used for screening for cognitive impairment, were examined in a sample of amphetamine abusers in drug abuse treatment programs. A mixed race sample (N = 185) was drawn from electronic files of data from the Drug Abuse Treatment Outcome Study (DATOS), a naturalistic, prospec tive cohort study that collected data from 1991 to 1993 in 96 programs in 11 cities in the United States. Data were analyzed to determine the effects of demographic variables on derived indices created by adding, subtracting, multiplying, and dividing Parts A and B of the TMT in this large treatment sample of substance abusers. The variables of sex, age, ethnicity, and education were not statistically significant for selected derived indices of the TMT.