How is the accuracy of a cognitive assessment evaluated?
The accuracy of a particular cognitive screen must be measured by its ability to correctly identify a cognitive problem (sensitivity) without incorrectly classifying a normal response as impaired (specificity). In general, the higher the sensitivity and specificity of a particular assessment tool are, the more accurate the results of that tool will be. In evaluating the accuracy of various assessment tools, it is important to consider the minimum severity of impairment that the tool can detect. Depending on the underlying medical condition, individuals often have mild cognitive impairment for seven or more years. While many tests claim a high accuracy rate for detecting moderate dementia, very few are sensitive enough to identify early stages of subtler impairment classified as mild cognitive impairment or mild dementia.
