1Defense and Veterans Brain Injury Center,Silver Spring,Maryland and Fort Bragg,North Carolina.
4Uniformed Service University of the Health Sciences,Bethesda,Maryland.
J Int Neuropsychol Soc. 2018 Feb;24(2):156-162. doi: 10.1017/S1355617717001187. Epub 2017 Nov 23.
The Automated Neuropsychological Assessment Metrics 4 TBI-MIL (ANAM4) is a computerized cognitive test often used in post-concussion assessments with U.S. service members (SMs). However, existing evidence remains mixed regarding ANAM4's ability to identify cognitive issues following mild traumatic brain injury (mTBI). Studies typically examine ANAM4 using standardized scores and/ or comparisons to a baseline. A more fine-grained approach involves examining inconsistency within an individual's performance (i.e., intraindividual variability).
Data from 237 healthy control SMs and 105 SMs within seven days of mTBI who took the ANAM4 were included in analyses. Using each individual's raw scores on a simple reaction time (RT) subtest (SRT1) that is repeated at the end of the battery (SRT2), we calculated mean raw RT and the intraindividual standard deviation (ISD) of trial-by-trial RT. Analyses investigated differences between groups in mean RT, RT variability (i.e., ISD), and change in ISD from SRT1 and SRT2.
Using regression residuals to control for demographic variables, analysis of variance, and pairwise comparisons revealed the control group had faster mean RT and smaller ISD compared to the mTBI group. Furthermore, the mTBI group had a significant increase in ISD from SRT1 to SRT2, with effect sizes exceeding the minimum practical effect for comparisons of ISD in SRT2 and change in ISD from SRT1 to SRT2.
While inconsistencies in performance are often viewed as test error, the results suggest intraindividual cognitive variability may be more sensitive than traditional metrics in detecting changes in cognitive function after mTBI. Additionally, the findings highlight the utility of the ANAM4's repeating a RT subtest at two points in the same session for exploring within-subject differences in performance variability. (JINS, 2018, 24, 156-162).
自动化神经心理评估指标 4 型创伤性脑损伤（ANAM4）是一种常用于美国军人（SM）脑震荡后评估的计算机化认知测试。然而，现有的证据仍然存在混合，关于 ANAM4 识别轻度创伤性脑损伤（mTBI）后认知问题的能力。研究通常使用标准化分数和/或与基线的比较来检查 ANAM4。更精细的方法涉及检查个体表现的不一致性（即个体内变异性）。
纳入了 237 名健康对照组 SM 和 105 名 mTBI 后七天内接受 ANAM4 的 SM 的数据。使用每个个体在简单反应时间（RT）子测试（SRT1）上的原始分数，该子测试在电池结束时重复（SRT2），我们计算了平均原始 RT 和逐次 RT 的个体内标准偏差（ISD）。分析了组间平均 RT、RT 变异性（即 ISD）和 SRT1 与 SRT2 之间 ISD 的变化差异。
使用回归残差控制人口统计学变量，方差分析和两两比较表明，对照组的平均 RT 更快，ISD 更小。此外，mTBI 组从 SRT1 到 SRT2 的 ISD 显著增加，效应大小超过了 SRT2 中 ISD 比较和 SRT1 到 SRT2 中 ISD 变化的最小实际效应。
虽然性能的不一致通常被视为测试误差，但结果表明个体内认知变异性可能比传统指标更能敏感地检测 mTBI 后认知功能的变化。此外，这些发现突出了 ANAM4 在同一会话的两个点重复 RT 子测试以探索性能变异性的个体内差异的效用。（JINS，2018，24，156-162）。
