Department of Medical Psychology, Radboud University Nijmegen Medical Centre, Expert Centre Chronic Fatigue, The Netherlands.
Psychol Med. 2010 Aug;40(8):1281-7. doi: 10.1017/S0033291709992212. Epub 2010 Jan 5.
Cognitive behaviour therapy (CBT) is known to reduce fatigue severity in chronic fatigue syndrome (CFS). How this change in symptomatology is accomplished is not yet understood. The purpose of the present study was to determine whether the effect of CBT on fatigue is mediated by an increase in physical activity.
Three randomized controlled trials were reanalysed, previously conducted to evaluate the efficacy of CBT for CFS. In all samples, actigraphy was used to assess the level of physical activity prior and subsequent to treatment or a control group period. The mediation hypothesis was analysed according to guidelines of Baron & Kenny [Journal of Personality and Social Psychology (1986)51, 1173-1182]. A non-parametric bootstrap approach was used to test statistical significance of the mediation effect.
Although CBT effectively reduced fatigue, it did not change the level of physical activity. Furthermore, changes in physical activity were not related to changes in fatigue. Across the samples, the mean mediation effect of physical activity averaged about 1% of the total treatment effect. This effect did not yield significance in any of the samples.
The effect of CBT on fatigue in CFS is not mediated by a persistent increase in physical activity.
认知行为疗法（CBT）已被证实可降低慢性疲劳综合征（CFS）患者的疲劳严重程度。但目前尚不清楚这种症状变化是如何产生的。本研究旨在确定 CBT 对疲劳的影响是否通过增加身体活动来介导。
重新分析了之前进行的三项随机对照试验，以评估 CBT 对 CFS 的疗效。在所有样本中，均使用活动记录仪在治疗或对照组期间之前和之后评估身体活动水平。根据 Baron 和 Kenny 的指南[人格与社会心理学杂志（1986）51，1173-1182]分析中介假设。使用非参数自举方法来检验中介效应的统计学意义。
尽管 CBT 有效地降低了疲劳感，但它并没有改变身体活动水平。此外，身体活动的变化与疲劳的变化无关。在所有样本中，身体活动的平均中介效应约为总治疗效果的 1%。在任何一个样本中，该效应均不具有统计学意义。
CBT 对 CFS 患者疲劳的影响不是通过持续增加身体活动来介导的。
