Derived trail making test indices in a sample of hallucinogen abusers: demographic effects.

Derived indices on the Trail Making test (TMT), a test often used for screening for cognitive impairment, were examined in a sample of hallucinogen abusers in drug abuse treatment programs. A mixed race sample (N = 128) was drawn from electronic files of data from the Drug Abuse Treatment Outcome Study (DATOS). The DATOS was a naturalistic, prospective 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 hallucinogen abusers. The variables of sex and age were not statistically significant for derived indices of the TMT. The variable of ethnicity was significant for the all derived indices except the ratio score (divide Part B by Part A) and the variable of education was significant for the interaction score (multiply Part A by Part B and divide by 100).