Background: Cognitive impairment due to delirium or dementia is common in older emergency department (ED) patients. To prevent errors, emergency physicians (EPs) should use brief, sensitive tests to evaluate older patient's mental status. Prior studies have shown that the Six-Item Screener (SIS) meets these criteria.
Objectives: The goal was to verify the performance of the SIS in a large, multicenter sample of older ED patients.
Methods: A prospective, cross-sectional study was conducted in three urban academic medical center EDs. English-speaking ED patients > or = 65 years old were enrolled. Patients who received medications that could affect cognition, were too ill, were unable to cooperate, were previously enrolled, or refused to participate were excluded. Patients were administered either the SIS or the Mini-Mental State Examination (MMSE), followed by the other test 30 minutes later. An MMSE of 23 or less was the criterion standard for cognitive impairment; the SIS cutoff was 4 or less for cognitive impairment. Standard operator characteristics of diagnostic tests were calculated with 95% confidence intervals (CIs), and a receiver operating characteristic curve was plotted.
Results: The authors enrolled 352 subjects; 111 were cognitively impaired by MMSE (32%, 95% CI = 27% to 37%). The SIS was 63% sensitive (95% CI = 53% to 72%) and 81% specific (95% CI = 75% to 85%). The area under the receiver operating characteristic curve was 0.77 (95% CI = 0.72 to 0.83).
Conclusions: The sensitivity of the SIS was lower than in prior studies. The reasons for this lower sensitivity are unclear. Further study is needed to clarify the ideal brief mental status test for ED use.