An Interrater Reliability Study of the Trail Making Test (Parts A and B)

In 1982 Lezak hypothesized that the current procedure used to administer and score the Trail Making Test had resulted in diminished reliability by increasing scorers' variance. 39 participants, trained in order to reduce subjects' performance variance, were given Parts A and B of the Trail Making Test by four different experienced psychometrists. The interrater reliability on both parts was high ( r Part A = .94; r Part b = .90), which suggests that, at least with experienced examiners, substantial variance of scorers is not introduced.