Color-word stroop test (CWST)
’
SAID, CARD
The standardized version of the paper-based color-word Stroop test revised by Golden (1975), consisting of 3 cards listing 100 items each presented in a “5 (columns) × 20 (rows)” matrix was used in the present study. The card I (word; W) included randomly distributed 100 words (red, green, and blue) printed in black ink on a white sheet while no word was followed by itself in a column. Card II (color; C) consists of 100 colors (written as XXXX in color) printed in either red, green, or blue on a white sheet in which no color was followed by itself in a column or matched the corresponding word on card I. This means none of the colors on card II match the position of the words on card I. Finally, card III (color-word; CW) contained 100 colored words on a white sheet in which the order of words from the card I was printed in the order of the colors from card II. This way no word for a color matched that particular color. The participants were given all three cards with card ‘W’ on top as the first card, followed by card ‘C’ as the second one, then card ‘CW’ as the third card, placed in front of them on a flat surface. They were instructed to read out loud as many items in each card in 45 s (45 s per card) as quickly as they could. Accordingly, the participants started the test by reading down the columns of card ‘W’ within 45 s when the experimenter stopped them and circled the last item read by the participants. The same procedure was applied for cards ‘C’ and ‘CW’. If there was a mistake, the experimenter said “No” and the participants had to correct the mistake and continue the test. Moreover, if the participants finished all the columns of each card before 45 s, they were instructed to return to the first column of that card and read again. The number of items correctly named in 45 s in each card was recorded and used to calculate the predicted CW (PCW) score according to the following formula: [PCW = (W × C) / (W + C)]. Then, the PCW score was subtracted from the actual score of the CW card (number of items correctly named in CW card) leading to obtaining the interference score (IG) as follows: IG = CW – PCW [