Five digit test (FDT) is appropriate both for English and non-English speakers, and competent readers and illiterate subjects, and is useful for people with reduced color vision. The cognitive requirements of doing the tasks are very low. The subject need to name digits 1 to 5 and recognized perceptual pattern of 1 to 5 elements (L. DeCristoforo, Drexler, Riley, Lang, & Sedo, 2001; Hsieh & Tori, 2007).
It is divided into four parts. Each part contains 50 items. The items are groups of digits or stars printed inside the frames. The digits can either be named as the number printed in the frame (two 5s are read as “five”), or counted how many digits are in the frame (two 5s are counted as “two”). Part 1 and part 2 measure processing speed (speed of production). Part 3 and part 4 measure response inhibition and substitution of spontaneous responses. In part 1, a subject reads groups of digits. In part2, the subject counts groups of stars. In part 3, the subject counts conflictive items and items and avoids naming them (if two 5s are presented, the correct response is “two” and not “five”). In part 4, the subject needs to switch between counting (80% of the items) and naming (20% of the items) the number, whenever the item has a darker frame. For each part, test scores are the amount of performance time in seconds plus the total of errors made (Hsieh & Tori, 2007; McLachlan, Lang, DeCristoforo, & Sedo, 2004; Verdejo, Toribio, Orozco, Puente, & Perez-Garcia, 2005).
In Part 1, recording the time response to the 25th item (midpoint) and whole testing time could help to determine whether examinees are able to sustain their initial speed. The time response of the first half section (1st-25th) and the time response of the second half section (26th-50th) may be equal. The examinees may not show sustained performance (slower in the second half section), or improve with practice (faster in the second half section). Part 1 and Part 2 were designed to assess the ability of automatically allocating attention to visual space, related to the functioning of the posterior attentional subsystem. Part 3 and Part 4 were designed to examine the effortful ability to attention or select from multiple streams of cognitive processing, associated with the executive attentional subsystem (Lang, 2002).
The reaction time of part 3 minus the reaction time of part 1 indicates the ability of inhibition. The reaction time of part 4 minus the reaction time of part 1 indicates ability of flexibility. The reaction time of part 3 indicates selective attention. The reaction time of Part 4 indicates alternating attention (Milner, 1986; Sedo, 2007, 2008).
Concurrent validity of the FDT was found with well established measure of simple, complex and divided attention, and spatial reasoning (McLachlan & sedo, 2003). Convergent validity of the part 1, part 2, part 3, and part 4 of the FDT with the Stroop test were Pearson’s correlation coefficients between 0.24-0.71, 0.51-0.72, 0.51-0.66, and 0.50-0.67, respectively (L. A. DeCristoforo, 2000).
DeCristoforo, L., Drexler, M., Riley, N., Lang, J., & Sedo, M. (2001). A stroop alternative for non-English speakers: an exploratory factor analysis of the Five-Digit Test. Paper presented at the The National Academy of Neuropsychology Convention, San Francisco, California.
DeCristoforo, L. A. (2000). Normative and validation study of the Five Digit Test in older adults. Doctoral disseration, San Francisco.
Hsieh, S. L., & Tori, C. D. (2007). Normative data on cross-cultural neuropsychological tests obtained from Mandarin-speaking adults across the life span. Arch Clin Neuropsychol, 22(3), 283-296.
Lang, J. A. (2002). Validation of the five digit test in a clinical sample: an alternative to the stroop color-word task with possible cultural implications. Doctoral dissertation, Alliant International University, San Francisco.
McLachlan, J. F. C., Lang, J. A., DeCristoforo, L. A., & Sedo, M. A. (2004). A non-reading alternative to the stroop: normative data on 126 adult patients. Paper presented at the The XV Scientific Fair of the Massachusetts Neuropsychological Society, Boston.
McLachlan, J. F. C., & sedo, M. A. (2003). The Five-Digit Test: validity and utility in neuropsychological evaluation. Clinical Neursopsychologist, 17(1), 102.
Milner, A. D. (1986). Chronometric analysis in neuropsychology Neuropsychologia, 24(1), 115-128.
Sedo, M. A. (2007). FDT / Test de los cinco digitos: Manual. Madrid: TEA.
Sedo, M. A. (2008). Five Digit Test: a cross-cultural test of executive functions.
Verdejo, A., Toribio, I., Orozco, C., Puente, K. L., & Perez-Garcia, M. (2005). Neuropsychological functioning in methadone maintenance patients versus abstinent heroin abusers. Drug Alcohol Depend, 78(3), 283-288.