The symbol trail making test: test development and utility as a measure of cognitive impairment

Although the Trail Making Test (TMT) has proven to be an exceptional clinical tool, its applications have been limited by the instrument's use of the Arabic numeral system and Latin alphabet. Clearly an instrument not limited by a specific alphabet or numerical system could fill this void. This study presents the development and validation of an alternative to the TMT that offers modestly similar psychometric properties and can be used with populations that have no familiarity with the Arabic numerical system or a specific alphabet. The Symbol Trail Making Test (STMT), which employs symbols that are not language or numerically based was administered to a normative sample of 210 participants, including 54 individuals whose first language was not English, for the purpose of collecting normative data. Reliability, assessed through an alternate form administration, and convergent validity, assessed through correlation with the TMT in a nonpatient sample, was deemed acceptable. Significant discriminant validity was obtained comparing non-brain-injured patients to brain-injured patients, particularly on time measures. An analysis of variance found no significant difference between native English speakers and individuals speaking English as a second language on performance on the STMT. This preliminary study provides evidence that the STMT is a clinically useful instrument for discriminating brain-injured from non-brain-injured participants without employing a specific culture-bound symbol system.