THE EXPANDED TRAIL MAKING TEST - RATIONALE, DEVELOPMENT, AND PSYCHOMETRIC PROPERTIES

Many procedures have been employed to determine the specific cognitive components necessary for successful Trail Making Test (TMT) performan ce. Yet, there is still considerable disagreement in the literature as to what these components might be. The present study explores an alte rnative methodology to address this problem. By systematically varying the stimuli within the TMT format, it may eventually be possible to i solate the cognitive demands of this test. As the first step toward th is goal, two experimental forms of the TMT, forms X and Y, were develo ped and subjected to empirical validation. The results indicate that t his Expanded Trail Making Test possesses adequate concurrent and crite rion validity to support the proposed methodology. The results also su ggest that the psychometric properties of the TMT format are robust to alterations in test stimuli. Secondary benefits of this methodology i n terms of explaining between-group variance and in terms of cross-cul tural assessment, are discussed. (C) 1998 National Academy of Neuropsy chology. Published by Elsevier Science Ltd.