Executive functions in a Turkish sample: associations with demographic variables and normative data

Attention and executive functions are affected by demographic factors. The study presented in this paper examines the effects of education, gender, and age on the scores of the Color Trail Test (CTT) (D'Elia, Satz, Uchiyama, & White, 1999) and the Visual Verbal Test (VVT) (Feldman & Drasgow, 1959), which are considered to be measures of executive functions such as attention, cognitive flexibility, set shifting, abstraction, and concept formation. This paper also presents the normative data for 611 cognitively intact adult Turkish participants (male:female ratio = 361:250; age range = 20-100 years, mean age = 52.038; education range = 0-25 years, mean education = 9.01). As expected, the effects of age and education were significant and sizeable, but the effect of gender was small. Results showed that the CTT and the VVT performances were lower for higher ages and lower educational levels. Based on these results, the current norms for both tests were stratified for age and education.