The Letter Digit Substitution Test (LDST) is based on earlier developed substitution tests (e.g., Digit Symbol Substitution Test; Wechsler, 1955, 1981) but uses over-learned signs instead of the symbols used in other substitution tests. The written and oral versions of the LDST were administered to a large, cognitively screened sample (N = 1,858) of adults aged 24 to 81 years. Age was the most important predictor of LDST performance, and females outperformed males. A low level of education profoundly influenced LDST performance: the effect of a low versus high level of education on LDST performance was comparable to about 20 years of aging. Regression-based normative data were prepared for both the written and oral versions of the LDST.
|Journal||Journal of Clinical and Experimental Neuropsychology|
|Publication status||Published - 1 Jan 2006|
van der Elst, W., van Boxtel, M. P. J., van Breukelen, G. J. P., & Jolles, J. (2006). The Letter Digit Substitution Test: normative data for 1,858 healthy participants aged 24-81 from the Maastricht Aging Study (MAAS): influence of age, education, and sex. Journal of Clinical and Experimental Neuropsychology, 28, 998-1009. https://doi.org/10.1080/13803390591004428