Table 1.

Summary of features.

Features	Category	Number	Description
Fixed	Patient information	6	Sex, age, visit method(2), reason of visit(2)
	Past medical histories	7	Hypertension, diabetes mellitus, pulmonary tuberculosis, hepatitis viral carrier, allergies, medications, operations
	Chief complaints and duration	6	Chief complaints categorized into 15 groups; cardiovascular, pulmonary/respiratory, gastrointestinal organs, gastrointestinal bleeding, neurologic, genitourinary, obstetric/gynecological, musculoskeletal, ophthalmologic, ear/nose/throat, skin, orofacial, psychiatric, medical device related, other general issues. If multiple complaints exist in each patient, up to 3 categories (3) and its duration(3) were used
	Vital signs on arrival	8	Systolic blood pressure(2), diastolic blood pressure(2), respiratory rate, pulse rate, oxygen saturation, body temperature
Observation	Clinical observation	6	Systolic blood pressure, diastolic blood pressure, respiratory rate, pulse rate, oxygen saturation, body temperature
	Mental status monitoring	1	Change of mental status; alert, drowsy, stuporous, semi-comatose, comatose, confused and sedated
	Electrocardiogram diagnosis	23	Coronary(5), electrophysiologic(12), metabolic (5), unspecified(1)
	Electrocardiogram metrics	8	P axes, R axes, T axes, PR interval, QRS duration, QT, QTc, ventricular rate
	Laboratory test	55	Arterial blood gas analysis result(12), regular laboratory results(43)