Influence of 8-bit vs 11-bit Digital Displays on Observer Performance and Visual Search: A Multi-Center Evaluation

摘要

Monochrome monitors typically display 8 bits of data (256 shades of gray) at one time. This study determined if monitors that can display a wider range of grayscale information (11-bit) can improve observer performance and decrease the use of window/level in detecting pulmonary nodules. Three sites participated using 8 and 11-bit displays from three manufacturers. At each site, six radiologists reviewed 100 DR chest images on both displays. There was no significant difference in ROC Az (F = 0.0374, p = 0.8491) as a function of 8 vs 11 bit-depth. Average Az across all observers with 8-bits was 0.8284 and with 11 -bits was 0.8253. There was a significant difference in overall viewing time (F = 10.209, p = 0.0014) favoring the 11-bit displays. Window/level use did not differ significantly for the two types of displays. Eye position recording on a subset of images at one site showed that cumulative dwell times for each decision category were lower with the 11-bit than with the 8-bit display. T-tests for paired observations showed that the TP (t = 1.452, p = 0.1507), FN (t = 0.050, p = 0.9609) and FP (t = 0.042, p = 0.9676) were not statistically significant. The difference for the TN decisions was statistically significant (t = 1.926, p = 0.05). 8-bit displays will not impact negatively diagnostic accuracy, but using 11-bit displays may improve workflow efficiency.