Cancer-Related Fatigue: Central or Peripheral? Tugba Yavuzsen, MD, Mellar P. Davis, MD, FCCP, Vinoth K. Ranganathan, MSE, MBA, Declan Walsh, MSc, FACP, FRCP, Vlodek Siemionow, PhD, Jordanka Kirkova, MD, Dilara Khoshknabi, MD, Ruth Lagman, MD, MPH, Susan LeGrand, MD, FACP, Guang H. Yue, PhD  Journal of Pain and Symptom Management  Volume 38, Issue 4, Pages 587-596 (October 2009) DOI: 10.1016/j.jpainsymman.2008.12.003 Copyright © 2009 U.S. Cancer Pain Relief Committee Terms and Conditions

Fig. 1 Schematic diagram for subject positioning, and recording force, electromyogram (EMG), and electroencephalogram (EEG). Journal of Pain and Symptom Management 2009 38, 587-596DOI: (10.1016/j.jpainsymman.2008.12.003) Copyright © 2009 U.S. Cancer Pain Relief Committee Terms and Conditions

Fig. 2 Mean intensity of the BFI score (0–10) for each question in CRF group and control group (P<0.001) (means±standard deviation). Question 1—please rate your fatigue (weariness, tiredness) by circling the one number that best describes your fatigue right now; Question 2—please rate your fatigue (weariness, tiredness) by circling the one number that best describes your usual level of fatigue during the past 24 hours; Question 3—please rate your fatigue (weariness, tiredness) by circling the one number that best describes your worst level of fatigue during the past 24 hours; Question 4—circle the one number that describes how, during the past 24 hours, fatigue has interfered with your: 4a—general activity, 4b—mood, 4c—walking ability, 4d—normal work (includes both work outside the home and daily chores), 4e—relations with other people, 4f—enjoyment of life. Journal of Pain and Symptom Management 2009 38, 587-596DOI: (10.1016/j.jpainsymman.2008.12.003) Copyright © 2009 U.S. Cancer Pain Relief Committee Terms and Conditions

Fig. 3 Normalized TF (mean±standard deviation) at rest (TFrest) and after SC (TFfatigue). Journal of Pain and Symptom Management 2009 38, 587-596DOI: (10.1016/j.jpainsymman.2008.12.003) Copyright © 2009 U.S. Cancer Pain Relief Committee Terms and Conditions

Fig. 4 The ratio (%) of TF to voluntary force during SC (TFSC) to the rest TF before SC (TFrest). Journal of Pain and Symptom Management 2009 38, 587-596DOI: (10.1016/j.jpainsymman.2008.12.003) Copyright © 2009 U.S. Cancer Pain Relief Committee Terms and Conditions