Diagnostic accuracy of displays unaffected by DICOM standard calibration

No significant differences were seen between the diagnostic accuracy in medical-grade gray scale displays and consumer-grade color displays with and without the calibration method established by the DICOM standard calibration method, according to a study published in the June issue of the American Journal of Roentgenology.

Established to prevent inconsistent presentation of medical images, the DICOM gray-scale standard display function (GSDF) offers a calibration method for producing consistent images. The method includes a just-noticeable difference in luminance and distributes the luminance range of a display system based on the Barten model. To compare the clinical effect of the presence or absence of GSDF calibration on the diagnostic accuracy of reading images on LCD or LED consumer-grade displays, lead author Antonio J. Salazar, of the University of Los Andes in Colombia, and colleagues examined 76 cases.

During the study, six radiologists evaluated conditions including interstitial opacities, pneumothorax and nodules from three displays and two display calibrations for a total of 2,736 observations in a multireader, multicase factorial design. Analysis of one medical-grade gray-scale display and two consumer-grade color displays occurred during the study. The readers did not observe any significant differences in image quality perception in the presence or absence of calibration. Similar forms of the ROC curves were seen and no significant differences were detected in diagnostic accuracy, accuracy of condition classification, false-positive rates, false-negative rates and image-quality perception. Strong agreement between readers was also observed for each display with and without calibration.

“These results allow us to conclude that GSDF calibration had no effect on the performance achieved with the three tested displays and with the selected chest conditions and observers,” wrote Salazar and colleagues. “Our results suggest that the tested displays may be recommended for reading digital chest radiographs,” they concluded.