Department of Clinical Epidemiology, Biostatistics and Bioinformatics, University of Amsterdam, NL-1100 DD Amsterdam, The Netherlands.
Dement Geriatr Cogn Disord. 2009;28(5):486-92. doi: 10.1159/000250593. Epub 2009 Nov 27.
BACKGROUND/AIMS: To examine whether brevity can be combined with precision in measuring global cognitive ability in patients with cerebrovascular disease (CVD) or vascular dementia (VaD). Longer tests (e.g. the CAMCOG) are precise but inefficient, whereas brief tests (e.g. the MMSE) are efficient but imprecise.
A simulated computerized adaptive testing (CAT) algorithm using existing CAMCOG data from 284 patients with CVD of whom 55 were diagnosed with VaD. CAT was used to estimate each individual patient's total score on a large precise test (the CAMCOG). CAT repeatedly selected only items of appropriate difficulty, depending on whether the previous item was (in)correctly responded to. CAT estimates were compared with total scores on the whole CAMCOG.
Even though there was an average test reduction of more than 40%, CAT estimates were in very high agreement with the whole test results (intraclass correlation >0.97) and had similar accuracy for the diagnosis of dementia (area under the curve = 0.94).
CAT combines efficiency with precision in the measurement of global cognitive ability in CVD patients.
背景/目的：探讨在测量脑血管疾病（CVD）或血管性痴呆（VaD）患者的整体认知能力时，是否可以做到既简洁又精确。较长的测试（如 CAMCOG）虽然精确但效率低下，而简短的测试（如 MMSE）虽然效率高但不精确。
利用 284 例 CVD 患者的现有 CAMCOG 数据，采用模拟计算机自适应测试（CAT）算法，其中 55 例被诊断为 VaD。CAT 用于估计每位患者在大型精确测试（CAMCOG）上的总分。CAT 根据前一个项目的回答是否正确，反复选择适当难度的项目。将 CAT 估计值与整个 CAMCOG 的总分进行比较。
尽管测试平均减少了 40%以上，但 CAT 估计值与整个测试结果非常吻合（组内相关系数>0.97），并且对痴呆症的诊断具有相似的准确性（曲线下面积=0.94）。
CAT 在测量 CVD 患者的整体认知能力时，实现了效率与精确性的结合。
