Application of the Trail Making Test in differentiating neuropsychological impairment of elderly persons

This study investigated differences in Trail Making Test performance as a function of over-all level of neuropsychological impairment in a sample of elderly patients diagnosed as having various dementing diseases. Patients were classified as mildly, moderately, or severely impaired (ns = 19, 25, 26) based on the seven measures used to compute the Impairment Index of the Halstead-Reitan Neuropsychological Battery. The mean ages for the mildly, moderately, and severely impaired groups were 67.72, 71.56, and 71.16 yr., respectively. Using level of impairment as the grouping variable, subjects were compared on the mean number of seconds required to complete Trail Making Test A, B, and A + B. Three one-way analyses of variance indicated significant differences for Parts A, B, and A + B. As over-all level of impairment increased, time required to complete the Trail Making Test increased. Results are discussed and directions for further research are recommended.