**2.4.1 Fatigue Impact Scale (FIS) (Fisk,1994; Hassoun, 2002; Jones, 2009)**

FIS is a validated questionnaire for assessing fatigue. It is used in many chronic conditions. The multidimensional assessment of fatigue is complicated by the interrelation of its multiple causes and effects. A significant proportion of liver patients suffer fatigue, even patients with non advanced disease. Fatigued patients have more sleep problems and higher depression scores than non-fatigued patients (Poynard, 2002). Self rated depression is present in 28% of fatigued patients compared with 4% of non-fatigued patients. Long term fatigue affects 68% of the patients with PBC but it is not related to the severity of their liver disease (Morana, 2009).
