New brief tool to screen for cognitive impairment in elderly patients

December, 2010

A 2-minute questionnaire does an excellent job of indicating older adults with cognitive impairment.

A simple new cognitive assessment tool with only 16 items appears potentially useful for identifying problems in thinking, learning and memory among older adults. The Sweet 16 scale is scored from zero to 16 (with 16 representing the best score) and includes questions that address orientation (identification of person, place, time and situation), registration, digit spans (tests of verbal memory) and recall. The test requires no props (not even pencil and paper) and is easy to administer with a minimum of training. It only takes an average of 2 minutes to complete.

A score of 14 or less correctly identified 80% of those with cognitive impairment (as identified by the Informant Questionnaire on Cognitive Decline in the Elderly) and correctly identified 70% of those who did not have cognitive impairment. In comparison, the standard MMSE correctly identified 64% of those with cognitive impairment and 86% of those who were not impaired. In other words, the Sweet 16 missed diagnosing 20% of those who were (according to this other questionnaire) impaired and incorrectly diagnosed as impaired 30% of those who were not impaired, while the MMSE missed 36% of those who were impaired but only incorrectly diagnosed as impaired 14% of those not impaired.

Thus, the Sweet 16 seems to be a great ‘first cut’, since its bias is towards over-diagnosing impairment. It should also be remembered that the IQCDE is not the gold standard for cognitive impairment; its role here is to provide a basis for comparison between the new test and the more complex MMSE. In comparison with a clinician’s diagnosis, Sweet 16 scores of 14 or less occurred in 99% of patients diagnosed by a clinician to have cognitive impairment and 28% of those without such a diagnosis.

The great benefit of the new test is of course its speed and simplicity, and it seems to offer great promise as an initial screening tool. Another benefit is that it supposedly is unaffected by the patient’s education, unlike the MMSE. The tool is open access.

The Sweet 16 was developed using information from 774 patients who completed the MMSE, and then validated using a different group of 709 older adults.