Coronary calcium score improves the estimation for pretest probability of obstructive coronary artery disease and avoids unnecessary testing in individuals at low extreme of traditional risk factor burden: validation and comparison of CONFIRM score and genders extended model

Table 4 Reclassification table using PTP categories < 15%, 15–85%, and > 85% (Individuals with 1 RF)

PTP category based on GEM	PTP category based on CONFIRM score			Total	Reclassification^a		NRI^b	P value for NRI
PTP category based on GEM	Low	Medium	High	Total	Up	Down	NRI^b	P value for NRI
Negative individuals					16.64%	36.06%	21.1%	< 0.0001
Low	418	592	11	1021
Medium	252	410	32	694
High	15	26	5	46
Total	685	1028	48	1761
Positive individuals^c					13.15%	11.47%
Low	19	46	5	70
Medium	11	439	24	474
High	3	72	35	110
Total	33	557	64	654

Abbreviations as in Table 3
^aIndividuals was reclassified by GEM and was compared to CONFIRM score
^bNRI = [P(Up|Positive)- P(Down|Positive)]-[P(Up|Negative)- P(Down|Negative)]
^cPositive individuals was defined as those had at least one lesion with ≥50% diameter stenosis or any non-assessable segments due to severe calcification on CCTA

ISSN: 1471-2261