Cunje Alwin, Molloy D William, Standish Timothy I, Lewis David L
Department of Family Medicine, University of Ottawa, Ottawa, Ontario, Canada.
Int Psychogeriatr. 2007 Feb;19(1):65-75. doi: 10.1017/S1041610206003425. Epub 2006 May 10.
Repeat cognitive testing is an essential diagnostic strategy to measure changes in cognition over time when following people with memory problems. Alternate forms may avert practice effects that can mimic improvements in cognition. We evaluated alternate forms of verbal fluency and logical memory (paragraph recall) tasks to evaluate their equivalence for clinical use.
Participants with mild cognitive impairment (MCI) and dementia were recruited from five outpatient memory clinics and one nursing home. Participants with normal cognition (NC) were recruited from family members or friends. Verbal fluency categories of animals, cities & towns, fruits & vegetables and first names were used. Scores were recorded for 0-30 seconds, 31-60 seconds and errors. For the logical memory task, participants were read one of three different paragraphs and then were asked to recall the story. Immediate recall and delayed recall scores were recorded. The Standardized Mini-mental State Examination, the AB Cognitive Screen and the 15-point Geriatric Depression Scale were administered as part of the assessment. Analyses were performed using means, frequency distributions, t-tests, receiver-operating characteristic curves and effect sizes.
There were 46 NC participants, 45 with MCI and 55 with dementia. For verbal fluency, the mean number of animals, cities & towns, names or fruits & vegetables named in 60 seconds did not differ significantly within each cognitive group. First names was an easier category than the others: NC named 16.9-22.3 items, MCI named 11.6-14.4 items and dementia named 8.1-11.4 items. The mean number of items immediately recalled in logical memory was not significantly different for the three paragraphs. The verbal fluency task (in 60 seconds) and logical memory immediate recall were highly sensitive and specific to differences between NC and MCI (areas under the curves 0.87 and 0.76, respectively).
Alternate forms allow serial testing without learning bias. Verbal fluency and logical memory tasks are sensitive to early cognitive changes.
对于有记忆问题的人群进行随访时，重复认知测试是测量认知随时间变化的一项重要诊断策略。采用不同形式可以避免可能会模拟认知改善的练习效应。我们评估了言语流畅性和逻辑记忆（段落回忆）任务的不同形式，以评估它们在临床应用中的等效性。
从五个门诊记忆诊所和一家养老院招募了轻度认知障碍（MCI）和痴呆患者。认知正常（NC）的参与者从家庭成员或朋友中招募。使用了动物、城镇、水果和蔬菜以及名字的言语流畅性类别。记录0至30秒、31至60秒的得分以及错误情况。对于逻辑记忆任务，向参与者朗读三个不同段落中的一个，然后要求他们回忆故事。记录即时回忆和延迟回忆得分。作为评估的一部分，进行了标准化简易精神状态检查、AB认知筛查和15分老年抑郁量表测试。使用均值、频率分布、t检验、受试者操作特征曲线和效应量进行分析。
有46名NC参与者、45名MCI患者和55名痴呆患者。对于言语流畅性，每个认知组在60秒内说出的动物、城镇、名字或水果和蔬菜的平均数量没有显著差异。名字类别比其他类别更容易：NC组说出16.9至22.3个项目，MCI组说出11.6至14.4个项目，痴呆组说出8.1至11.4个项目。逻辑记忆中即时回忆的平均项目数在三个段落之间没有显著差异。言语流畅性任务（60秒内）和逻辑记忆即时回忆对NC和MCI之间的差异具有高度敏感性和特异性（曲线下面积分别为0.87和0.76）。
不同形式允许进行系列测试而无学习偏差。言语流畅性和逻辑记忆任务对早期认知变化敏感
