COMPONENTS OF PERFORMANCE IN CONCENTRATIO N TESTS - A STUDY WITH SYSTEMATICALLY VARIED CANCELING TESTS

Undergraduates (N = 121) completed a modified version of the d2 Test ( Brickenkamp, 1994) and three more versions in which certain features o f the test were systematically varied. The aim was to assess specific components of the test performance: Marking the targets (circle test), discrimination of the signs on one (d-test) or two levels (flag test) . The modified d2 correlated .59 with the d-test, .57 with the Rag tes t, and .23 with the circle test (number of items worked on). Errors (p ercent) were only weakly correlated, r(s)=.13 and .34. All indicators proved to be largely independent of intelligence (LPS subtest 3). The results are discussed with respect to the validity of the d2 Test and a theory of concentration performance (Westhoff & Kluck, 1984).