Effects of Age and Intelligence on Trail Making Test Performance and Validity

The literature contains evidence that age and intelligence affect Trail Making Test (TMT) performance and probably its validity as a screening device for organicity. This study systematically explored the nature of these effects. The TMT and WAIS were administered to 93 brain-damaged patients and 106 control patients, ranging in age from 20 to 72 yr. The results showed that: (1) TMT performance decreased with age, as did TMT validity; (2) TMT performance increased with intelligence; and (3) Reitan's (1958) cut-off point misclassified half the control patients, the misclassification rate increasing markedly with age. The results clearly indicate the need for local age-corrected norms.