Table 3.

Classification of CTE according to the WHO

	Symptoms	Cognitive defects	Neurological abnormalities
Class I	Fatigue, diminished memory, concentration and initiative	No objective dysfunction	No objective abnormalities
Organic affective syndrome	Change in personality. Poor impulse control, lowered mood and motivation, irritability, anxiety, emotional lability
Class II	Difficulties in concentration and attention, impairment of memory, decrease in learning capacity	Objective evidence of cognitive impairment	Minor neurological signs
Mild chronic toxic encephalopathy
Class III	Marked global deterioration in intellect and memory	Marked global deterioration in intellect and memory	Neurological signs and/or neuroradiological abnormal findings
Severe chronic toxic encephalopathy