Abstract
The increasing prevalence of Alzheimer's disease (AD) suggests that there is an increasing need for accurate and easily administered screening instruments. The Seven-Minute Screen is a neurocognitive screening battery consisting of four brief tests (enhanced cued recall, temporal orientation, verbal fluency, and clock drawing). We studied 55 outpatients with probable AD, 40 healthy volunteers of comparable age, sex, and education and 31 elderly patients with other neuropsychological disorders. The aim of our study was to determine the validity and reliability of this test. Differences on individual tests were evaluated using the Student t test. (Recall: 6.4 ± 5.02/15.38 ± 0.95; Orientation: 48.76 ± 42.74/0.2 ± 0.52; Verbal: 8.2 ± 4.94/18.05 ± 4.63; Clock drawing: 2.07 ± 2.56/6.03 ± 11.25 for AD patients and control subjects, respectively). Mean scores for patients with AD and control subjects on all four individual tests were significantly different (for each, p < 0.001). The mean time to complete the test for healthy control subjects was nine minutes and 18 seconds, for neuropsychological disorders nine minutes and six seconds, and for AD patients 13 minutes and 32 seconds (p < 0,001). Logistic regression analysis was used to determine the degree to which the battery discriminated between control subjects and patients with AD (sensitivity 92.73 percent and specificity 97.50 percent). We then separated the patients with MMSE > 20 and the same model of regression analysis was used. Sensitivity was 81.25 percent and specificity was 96.55 percent using 0.7 as the cutoff probability, and 93.75 and 96.55 percent, respectively, using 0.5 as the cutoff probability. Neither age nor education and gender had an effect on the results. The Seven-Minute Screen appears highly sensitive to AD patients and may be useful in helping to make initial distinctions between patients with early dementia and normal elderly.