A Preliminary Standardisation of the Bohnen et al. Version of the Stroop Color-Word Test for Setswana-Speaking University Students

The objective of this study was to undertake a preliminary standardisation of the Bohnen, Jolles, and Twijnstra (1992) version of the Stroop Color-Word Test for Setswana-speaking university students. The Bohnen et al. (1992) version (Bohnen Stroop), which is a modified version of the original Stroop Color-Word Test, is traditionally considered a neuropsychological measure of selective attention, otherwise known as concentration. In the present study, a computerised version of the Bohnen Stroop was administered to 102 Setswana-speaking university subjects between the ages of 18 and 30 years. Tests for normality indicated that, except for Subtask III and Interference Measure III-II, the distributions were not normal. Mann-Whitney test analysis indicated that age and gender significantly affected test performance, specifically: (a) although the 22–30 year-old group was (significantly) slower than the 18–21 year-old one on Subtask I (i.e. word reading) and Subtask II (i.e. colour naming), this same (i.e. older) group was faster — and thereby displaying reduced interference — on Interference Measure III-II (i.e. standard interference); and (b) the female group performed faster on Subtask II (i.e., colour-naming). Preliminary normative data, including z-scores and cut-off scores, were established. Furthermore, Cronbach's alpha calculations for the subtasks and interference measures yielded values ranging from .78 (Subtask III) to .88 (Subtask IV), thereby demonstrating acceptable internal consistency. Ultimately, however, the normative data are based on non-normal distributions and, therefore, a complete standardisation of the Bohnen Stroop is recommended.