Table 4.

Three most frequent trigger terms and number of unique trigger terms for the contextual property values negated, historical, hypothetical, and other for each of the six report types (SP: Surgical Pathology, DS: Discharge Summary, ECHO: Echocardiogram, ED: Emergency Department, OP: Operative Procedure, and RAD: Radiology) and all reports combined in the test set as applied by the ConText algorithm in the test set. Each cell contains up to three trigger terms, each of which is followed by the number of instances in which that trigger term was used by ConText to change the default value of a contextual property to the value given in the first row. The number of unique trigger terms (Unique) refers to the total number of different trigger terms found in the test set. For example, for Operative Procedure reports we list the three most frequent trigger terms for the value negated (“no”, “no evidence of”, and “free”), but two other trigger terms (namely, “not” and “with no”) were also used for a total of five unique trigger terms.

	negated		historical		hypothetical		Other
SP	No evidence of	2	History	4
	No	1
	Ruled out	1
	Unique:	3	Unique:	1	Unique:	0	Unique:	0
OP	No evidence of	12	For
	No	4	approximately	2
	Free	2	four months
			Status post	1
	Unique:	5	Unique:	2	Unique:	0	Unique:	0
RAD	No	20	History	3
	No evidence of	5
	No significant	1
	Unique:	3	Unique:	1	Unique:	0	Unique:	0
ECHO	No	15
	Without
	evidence of	6
	No evidence of	1
	Unique:	4	Unique:	0	Unique:	0	Unique:	0
DS	No	22	History	34	If	17	Family history	1
	Denied/denies	16	Experiences	17	Return	6
	Without	11	Status post	2	Should the	1
	Unique:	11	Unique:	6	Unique:	3	Unique:	1
ED	No	176	History	56	Return	14
	Denied/denies	59	For the last
	Not	20	several weeks	2
			Prior	1
	Unique:	18	Unique:	3	Unique:	1	Unique:	0
All	No	248	History	97	Return	20	Family history	1
	Denied/denies	76	Experiences	17	If	17
	No evidence of	28	Status post	3	Should the	1
	Unique:	18	Unique:	8	Unique:	3	Unique:	1