This study indicates that contrast-detail data should be very helpful in providing quantitative measurements of overall electronic display quality. The method would be suitable for new equipment selection, acceptance testing, and quality control. The recommended protocol would only involve observer data obtained using test images with mid-range background pixed values. Improvements to the current linear curve fit may also provide increased levels of measurement precision and sensitivity. To put the measurements in proper context, MTC measurements of a group of displays currently in use and deemed acceptable for the clinical display) should be obtained by a group of observers, if possible.
When making quantitative recommendations regarding equipment selection, or display configuration (eg, maximum display luminance or ambient room lighting levels), a group of observers should be used, since the decisions made will presumably affect a large number of radiologists, technologists or clinical physicians using the display workstations. With a group of five observers, and using the group paired difference analysis technique, measurement precision will be 9.0%, and sensitivity to MTC changes will be 11.1%. Each set of raw data for a measurement of MTC can be collected and analyzed for each observer in approximately 30 minutes, so data sufficient for a comparison of two devices could be collected and analyzed within an hour.
When making measurements for equipment acceptance testing or routine QC measurements (eg, on a quarterly or twice-yearly basis), measurements from a single observer should suffice since the goal is an assessment of the relative performance of an individual device. Precision of the single observer MTC measurements will be 6.8%, and sensitivity will be 15.2%. Measurements made over a period of time should have a reproducibility of about 5%.