Green P, Iverson G L
Private Practice with Neurobehavioural Associates, Edmonton, Alberta, Canada.
NeuroRehabilitation. 2001;16(4):237-43.
The purpose of this study was to examine the relationship between exaggeration and scores on a test of olfactory discrimination in patients being assessed in connection with a claim for financial benefits. Participants were 448 patients referred to a private practice in Edmonton, Alberta, Canada for psychological or neuropsychological assessment, related to evaluation of impairment and disability resulting from a work-related or non-work related accident. All patients were involved in some form of compensation claim at the time of their evaluation. All patients completed two tests designed to detect exaggerated cognitive deficits, the Computerized Assessment of Response Bias (CARB) and the Word Memory Test (WMT) as part of their evaluation. The diagnostic groups included 322 head injury cases, varying from very minor to very severe. Normative data for the smell test were derived from 126 patients with orthopedic injuries who passed both the CARB and the WMT. Patients with more severe traumatic brain injuries were 10-12 times more likely to have olfactory deficits than persons with trivial to mild head injuries. In a subgroup of patients who failed either the CARB or the WMT, there was no relationship between injury severity and total scores on the smell test. Therefore, the dose-response relationship between brain injury severity and olfactory deficits is severely attenuated when patients who are probably exaggerating their cognitive deficits are included in the analyses. Those patients with trivial to mild head injuries who demonstrated adequate effort on both the CARB and the WMT were no more likely to show olfactory deficits than the non-head-injured orthopedic control subjects. Therefore, anosmia following mild traumatic brain injury should not be concluded from self-reports or from tests of smell unless tests of effort have been passed. Effort should also be controlled in group studies of olfaction.
本研究的目的是调查在因申请经济赔偿而接受评估的患者中，夸大症状与嗅觉辨别测试分数之间的关系。研究对象为448名转诊至加拿大艾伯塔省埃德蒙顿一家私人诊所进行心理或神经心理评估的患者，这些评估与工作相关或非工作相关事故导致的损伤和残疾评估有关。所有患者在接受评估时都涉及某种形式的赔偿申请。作为评估的一部分，所有患者都完成了两项旨在检测夸大认知缺陷的测试，即反应偏差计算机评估（CARB）和词语记忆测试（WMT）。诊断组包括322例头部受伤病例，损伤程度从非常轻微到非常严重不等。嗅觉测试的标准数据来自126名通过CARB和WMT测试的骨科损伤患者。与轻度至中度头部受伤的患者相比，重度创伤性脑损伤患者出现嗅觉缺陷的可能性要高10至12倍。在CARB或WMT测试未通过的患者亚组中，损伤严重程度与嗅觉测试总分之间没有关系。因此，当分析中纳入可能夸大认知缺陷的患者时，脑损伤严重程度与嗅觉缺陷之间的剂量反应关系会严重减弱。那些轻度至中度头部受伤且在CARB和WMT测试中表现出足够努力的患者，与未头部受伤的骨科对照受试者相比，出现嗅觉缺陷的可能性并不更高。因此，除非通过努力测试，否则不应根据自我报告或嗅觉测试得出轻度创伤性脑损伤后嗅觉丧失的结论。在嗅觉的群体研究中也应控制努力程度。
