Reliability and Validity of a Danish Version of the Multiple Sclerosis Neuropsychological Screening Questionnaire.

Background: More than half of all patients with multiple sclerosis (MS) acquire cognitive impairment as part of their disease progression. Because cognitive dysfunction adds substantially to disability and coping strategies, a cost-effective screening tool is needed for cognitive impairment. The Multiple Sclerosis Neuropsychological Screening Questionnaire (MSNQ) has previously shown good validity in American, Argentinean, and Dutch MS cohorts. We sought to test reliability and validity of a Danish translation of the MSNQ compared with formal neuropsychological testing, and measures of depression and disability, and to compare self-reported cognition with Symbol Digit Modalities Test (SDMT) results.

Methods: Of 126 patients with MS and their informants tested with the MSNQ, 77 also underwent formal neuropsychological testing. All patients were tested with the SDMT and assessed clinically using the Expanded Disability Status Scale and MS Impairment Scale.

Results: The test-retest reliability of the MSNQ-P was significant (R = 0.79, P < .0001). R of informants (MSNQ-I) and patients (MSNQ-P) was much lower (R = 0.22, P < .0001). Compared with formal neuropsychological testing, the MSNQ-P and MSNQ-I performed poorly, with no correlation to individual neuropsychological tests, combined neuropsychological tests, or disability scores (Expanded Disability Status Scale and MS Impairment Scale). Depression/anxiety (Beck Depression Inventory) showed a weak linear relationship (R = 0.25, P < .0001), suggesting that the MSNQ-P measures these items more than the cognitive abilities of the patients.

Conclusions: This study does not support use of the MSNQ as a sensitive or valid screening tool for cognitive impairment in Danish patients with MS.