The invention relates to detection of encephalopathy based on EEG signal data obtained from a patient. A first signal component is derived from the EEG signal data, the first signal component representing low frequencies of the EEG signal data. A first parameter indicative of disorder in the first signal component and a second parameter indicative of disorder in EEG signal data representing a first frequency band are then computed, wherein the first frequency band includes higher frequencies than said low frequencies. An indicator of encephalopathy is then determined based on the first parameter and the second parameter, the indicator of encephalopathy being indicative of encephalopathy.