Socioeconomic Status Explains Sex Differences on the Trail Making Test: The Case of the Epirus Health Study Cohort Normative Data.

Objectives: Socioeconomic (SES) and health status (HS) are rarely considered when normative data are calculated. In the present study, normative data for the Trail Making Test (TMT) were developed from a large cohort and the association of sex, age and education, as well as HS and SES, with direct and derived TMT scores was explored.

Methods: Two thousand three hundred sixteen participants [1412 (61%) women; mean age: 47.11 (SD = 11.67) years; mean education: 14.82 (SD = 3.39) years] were drawn from the population-based Epirus Health Study. HS was rated on a self-reported scale and participants' medical conditions were recorded. SES was estimated from participants' after-tax income per month. The association of sex, age and education with TMT-A, TMT-B, TMT B-A and TMT B/A was explored with linear regression analyses. Hierarchical regression analyses were applied to control for HS and SES.

Results: Direct TMT scores were associated with sex, age and education (TMT-A: Bsex = 0.060, Bage = 0.322 and Beducation = -0.191; ΤΜΤ-Β: Bsex = 0.042, Bage = 0.330 and Beducation = -0.208). TMT B-A was associated with age (B = 0.176) and education (B = -0.130), whereas TMT B/A was not associated with any tested variable. SES, but not HS, was associated with TMT-A and TMT-B explaining the association of sex with TMT scores when included simultaneously in the model.

Conclusions: TMT performances are associated with age, education and sex. However, sex differences in direct TMT scores are attributed to underlying socioeconomic disparities in this large well-characterized cohort.