Objective: The Trail Making Test (TMT) is mainly used to assess visual scanning/processing speed (part A) and executive functions (part B). The test has proven sensitive at detecting cognitive impairment during aging. However, previous studies have shown differences between normative data from different countries and cultures, even when corrected for age and education. Such inconsistencies between normative data may lead to serious diagnostic errors, thus, the development of local norms is warranted. The purpose of this study was to provide regression-based normative data for TMT-A and -B, tailored for a large sample of French-speaking adults from Quebec (Canada).
Method: The normative sample consisted of 792 participants aged 50-91 years. Based on multiple linear regression, equations to calculate Z-scores were provided for TMT-A and -B, and for a contrast score which compared performance between TMT-A and -B. Percentiles, stratified by age, are presented for the number of recorded errors.
Results: Age was a significant predictor for TMT-A performance, while age and education were independently associated with performance on TMT-B. Gender did not have any effect on performance, in either condition. Education was the only significant predictor of the contrast score between TMT-B and TMT-A. Examiners should remain vigilant when two or more errors are recorded on the TMT-B since this was uncommon in the normative sample.
Conclusions: Our TMT normative data improve the accurate detection of visual scanning/processing speed and executive function deficits in Quebec (Canada) French-speaking adults.
Keywords: Norms/normative studies; Trail Making Test; attention; elderly/geriatrics/aging; executive functions.