Table 2.

The West Haven scale.

Stage	The West Haven criteria	Adapted West Haven criteria
0	No abnormality detected	Alert and attentive (oriented in time and space) without signs of encephalopathy (neither dysarthria, ataxia, flapping tremor, or obvious decrease in the speed of mental processing)
1	Trivial lack of awareness Euphoria or anxiety Shortened attention span Impairment performance of addition	Alert and attentive, but with at least one of the following signs: dysarthria, ataxia, flapping tremor, or obvious decrease in the speed of mental processing
2	Lethargy or apathy Minimal disorientation for time or place Subtle personality change Inappropriate behavior Impaired performance of subtraction	Awake but inattentive: disoriented, somnolent, easy to distract, and unable to perform easy mental tests (addition, subtraction, and remember a list of numbers) Patient's speech is easy to understand
3	Somnolence to semistupor but responsive to verbal stimuli Confusion Gross disorientation	Marked somnolence or psychomotor agitation Speech is difficult to understand
4	Coma (unresponsive to verbal or noxious stimuli)	Coma   The patient does not speak and does not follow simple commands (such as raising an arm or opening the mouth)