Validation of a 6 item cognitive impairment test with a view to primary care usage.

Abstract

To validate the 6 Item Cognitive Impairment Test (6CIT) against the Mini-Mental State Exam (MMSE) with a view to usage as a screening tool. Three groups with varying levels of dementia were tested using the MMSE, 6CIT and Global Deterioration Scale (GDS). Testing was carried out within Wiltshire, both in the community and outpatients. Patients were selected from a hospital database of dementia patients and were stratified into two groups according to GDS; a control group was also tested. Two hundred and eighty-seven patients were tested: 135 controls (GDS 1-2), 70 with mild dementia (GDS 3-5) and 82 with more severe dementia (GDS 6-7). The 6CIT and MMSE were found to correlate well, r(2)=-0.911 (p<0.01), when all groups were analysed. Correlation falls to r(2)=-0.754 (p<0.01) in the mild dementia group. In the GDS 3-5 group, the MMSE has a sensitivity and specificity of 51.43% and 100% respectively (cutoff 23/24). The 6CIT gives a sensitivity and specificity of 78.57% and 100% (cutoff 7/8). The 6CIT is a brief and simple test of cognition, which correlates well with the MMSE but outperforms it in milder dementia. The MMSE is of little value as a screening test for dementia.