Understanding interpretive errors in radiologists learning computed tomography colonography.
OBJECTIVE
To determine if interpretive errors in the course of learning CT colonography are secondary to failures in detection or in characterization and determine the types of lesions frequently missed.


METHODS
Fifteen radiologists completed an electronic CTC training module consisting of two parts: 1) a teaching file demonstrating the varied appearances of polyps, cancers, and pitfalls in interpreting exams; and 2) a test of 50 complete CTC datasets. Following review of each test case, radiologists were asked to indicate if and where a polyp was visualized. The module then showed each neoplasm (if any) located within the dataset. For false negative examinations, radiologists indicated if the lesion was not seen, was seen but interpreted as colonic wall or fold, or was seen but interpreted as stool or fluid.


RESULTS
The average sensitivity for sessile, pedunculated, and flat polyps for these novice readers was 76%, 63%, and 32%, respectively. Average sensitivity for all morphologies of cancers (annular, polypoid, flat) was high (93%, 85%, 95%), with 8/11 missed cancers being secondary to failure in detection. The most frequently missed cancer was an annular constricting tumor (5/11). Overall, 55% (73/132) of errors were failures of detection and 45% (59/132) were errors in characterization.


CONCLUSIONS
Radiologists learning CT colonography had slightly more errors of detection than characterization, but this difference was not statistically significant. Flat and pedunculated polyps and annular constricting cancers were the most frequently missed morphologies. Examples of these abnormalities should be emphasized in CTC training programs.
Fidler
Jeff L
JL
Department of Radiology, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA. fidler.jeff@mayo.edu
Fletcher
Joel G
JG
Johnson
C Daniel
CD
Huprich
James E
JE
Barlow
John M
JM
Earnest
Franklin
F
Bartholmai
Brian J
BJ
D003110:Colonic Neoplasms / Q000000981:diagnostic imaging*; D003111:Colonic Polyps / Q000000981:diagnostic imaging; D023881:Colonography, Computed Tomographic; D003951:Diagnostic Errors; D004502:Education, Medical, Continuing; D006801:Humans; D011871:Radiology / Q000193:education*; D012680:Sensitivity and Specificity