. Author manuscript; available in PMC: 2019 Mar 1.

Published in final edited form as: Gastroenterology. 2017 Nov 22;154(4):927–934.e4. doi: 10.1053/j.gastro.2017.11.025

Table 3.

Performance Characteristics of CT Colonography relative to Optical Colonoscopy for detecting lesions of all types¹^,²

Performance Characteristic	Lesion Size Category from Optical Colonoscopy
	≥6mm	≥10mm
Patient-Level Analyses³
Sensitivity	22/50 44.0 (30.2–57.8)^*	10/13 76.9 (54.0–99.8)
Specificity	169/181 93.4 (89.7–97.0)	194/218 89.0 (84.8–93.1)
Negative Predictive Value	169/197 85.8 (80.9–90.7)	194/197 98.5 (96.8–100)
Positive Predictive Value	22/34 64.7 (48.6–80.8)^*	10/34 29.4 (14.1–44.7)^*

number/total number, performance characteristic estimate and two-sided 95% Cell values include confidence intervals

Optical colonoscopy results are from initial pass before CTC results were revealed to gastroenterologist. CTC is defined as positive for a patient if at least one ≥6mm lesion as measured by CTC is detected.

Lesion size category represents maximum lesion size per patient as determined by optical colonoscopy.

operating characteristics significantly less than 90% (p<.05).