Bigi Sandra, Marrie R A, Till C, Yeh E A, Akbar N, Feinstein A, Banwell B L
Division of Neurology, Department of Pediatrics, The Hospital for Sick Children, Toronto, Canada.
Division of Child Neurology, Department of Pediatrics, The University Children's Hospital, University of Bern, Freiburgstrasse 15, 3010, Bern, Switzerland.
Neurol Sci. 2017 Apr;38(4):635-642. doi: 10.1007/s10072-017-2813-0. Epub 2017 Jan 11.
Decreased information processing speed (IPS) is frequently reported in pediatric multiple sclerosis (MS) patients. The computerized version of the Symbol Digit Modalities Test (c-SDMT) measures IPS over eight consecutive trials per session and additionally captures changes in performance within the session. Here, we establish normative c-SDMT performance and test-retest reliability in healthy children (HC) and explore differences in the overall c-SDMT-performance between HC and MS patients. This cross-sectional study included 478 HC (237 female, 49.5%) divided into five age groups (2 years each), and 27 MS patients (22 female, 81.5%) aged 8-18 years. The average time to complete the c-SDMT increased with age (|r| 0.70, 95% CI -0.74, -0.64). Test-retest reliability was high (ICC = 0.91) in HC. The total time to complete the c-SDMT did not differ between children with MS and sex- and age- matched HC (p = 0.23). However, MS patients were less likely to show faster performance across all the successive eight trials compared to HC (p = 0.0001). Healthy children demonstrate faster IPS with increasing age, as well as during successive trials of the c-SDMT. The inability of pediatric MS patients to maintain the increase in processing speed over successive trials suggests a reduced capacity for procedural learning, possibly resulting from cognitive fatigue.
小儿多发性硬化症（MS）患者经常出现信息处理速度（IPS）下降的情况。符号数字模态测试的计算机化版本（c-SDMT）在每个会话的连续八次试验中测量IPS，并额外记录会话期间的表现变化。在此，我们确定了健康儿童（HC）的c-SDMT表现规范和重测信度，并探讨了HC与MS患者在整体c-SDMT表现上的差异。这项横断面研究纳入了478名HC（237名女性，占49.5%），分为五个年龄组（每组2岁），以及27名8至18岁的MS患者（22名女性，占81.5%）。完成c-SDMT的平均时间随年龄增长而增加（|r| = 0.70，95% CI -0.74，-0.64）。HC的重测信度较高（ICC = 0.91）。MS患儿与性别和年龄匹配的HC完成c-SDMT的总时间没有差异（p = 0.23）。然而，与HC相比，MS患者在连续八次试验中表现出更快速度的可能性较小（p = 0.0001）。健康儿童随着年龄增长以及在c-SDMT的连续试验中表现出更快的IPS。小儿MS患者在连续试验中无法保持处理速度的增加，这表明程序学习能力下降，可能是由认知疲劳导致的。
