Table 3.

The clinical condition ‘vomiting’, which maps to both sensitive and specific gastrointestinal syndrome

Clinical condition: vomiting
Concept (relation to condition)	Keywords, regular expressions representing keywords and UMLS CUI
Vomiting (Condition name)	vmt, n/v, v/n, v/d, d/v, v+d, d+v, n+v, v+n, v + d, d + v, d & v, dry heaves, emsis, f v, fv, n v, n & v, n v, n v d, n&v, n+v, nv, nvd, retching, v d, v f, v&d, v+d, vimiting, viomiting, vmt, vo, voimiting, voiting, vom, vometing, vomi, vomikting, vomintg, vominting, vomit, vomited, vomiti, vomitibg, vomitin, vomitine, vomiting, vomitinig, vomitiong, vomitng, vomitt, vomitting, vomittng, vomitus, vommiting, vomoting, vomtiing, vomtiming, vomting, vomtiting, puke, n v, retching, v d, vomit, vomicking, cant hold any food down, threw up, throw up, throwing up, emesis, emisis
	Regular expressions (3 of 73 shown below) and UMLS CUI:
	\bd\s&\sv\b	C0042963 Vomiting
	\bdry heaves\b	C0232602 Retching
	\bvomitus\b	C0042965 Vomitus
Spitting up (Synonym)	Keywords:
	bringing up, spitting up
	Regular expressions and UMLS CUI:
	\bbringing\sup\b	C0042963 Spitting up
	\bspitting\sup\b	C0042963 Spitting up
Hematemesis (Related concept)	Keywords:
	hematemesis, coffee ground emesis, throw* up blood, vomit* blood
	Regular expressions and UMLS CUI:
	\bhematemesis\b	C00189261 Hematemesis
	\bcoffee\sground\semesis\b	C1510416 Coffee ground vomiting
	\b(throw\w*?\s+up|vomit)\s*\+\s*blood\b	C00189261 Hematemesis

A single clinical condition is composed of concepts that map to the condition as either the condition name, a synonym of the condition or a related condition. Each concept is associated with keywords used by implemented surveillance systems. We also created regular expressions for the keywords and mapped each regular expression to a UMLS concept unique identifier. Some regular expressions map to the same concept unique identifier (CUI).