The Reliability of the Brief Visuospatial Memory Test - Revised in Brazilian multiple sclerosis patients

Cognitive Impairment (CI) is a common and distressing problem in Multiple Sclerosis (MS). Its identification is complicated and sometimes omitted in the routine evaluation by neurologists. The BICAMS (Brief International Cognitive Assessment for Multiple Sclerosis) is a promising tool to overcome this difficulty. However, there is some concern regarding the subjectivity in scoring of the BVMT-R (Brief Visuospatial Memory Test - Revised), one of its components. OBJECTIVE: To evaluate the reliability of the BVMT-R in a sample of Brazilian MS patients, with the measure being administered and scored by neurologists. METHODS: BICAMS was applied to seventy subjects comprising forty patients diagnosed with MS and thirty healthy controls. In the MS patients group, the coefficients of agreement between three different raters, using the same protocols, and the internal consistency of the BVMT-R were assessed. Also, the coefficients of correlation of the BVMT-R with the other tests of the BICAMS, CVLT II (California Verbal Learning Test II) and SDMT (Symbol Digit Modalities Test), and their respective effect sizes were calculated. RESULTS: the BVMT-R presented a moderate inter-rater coefficient of agreement (k=0.62), an excellent Intraclass Correlation Coefficient (ICC=0.85), and high internal consistency (α=0.92). The correlation between the BVMT-R and CVLT II was moderate (ρ=0.36; p<0.025), but strong with the SDMT (ρ=0.60; p<0.01), with a large effect size. CONCLUSION: The BVMT-R is a reliable instrument for assessing CI in patients with MS, having a significant association with information processing speed, an aspect which should be considered when evaluating its score.