This study from the Netherlands looked at the validity and reliability over time of the Symbol Digit Modality Test (SDMT) and the Paced Auditory Serial Addition Test (PASAT), as an indicator of the cognitive state of people with MS. The researchers compared the long term results from these tests in relation to scores of the Brief Repeatable Battery of Neuropsychological tests (BRBN) in 485 people with MS. They then calculated the construct validity of the SDMT and PASAT three seconds test by comparing correlations with the BRBN-sumscore. They found higher correlations between the SDMT and BRBN compared to PASAT3 and BRBN in particular at the baseline. In the test-retest reliability, the highest coefficients were seen for the SDMT. A more distinct learning effect was seen for the PASAT3. Based on these results, the SDMT has better psychometric qualities than the PASAT3 as a single cognitive tool in people with MS.
Authors: Sonder JM, Burggraaff J
Source: Mult Scler. 2013 Sep 9. [Epub ahead of print]
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