Modalities of surveys to establish DRLs are arbitrarily fixed by national authorities or centres depending on their capabilities. Local DRLs defined in a centre for each X-ray device are commonly set up as the 75th percentile of the distribution of doses for pooled patients for one type of procedure performed on this device. National DRLs are commonly set up as the 75th percentile of the distribution of median doses calculated for pooled devices. In both situations, among variabilities inherent to the dose metrics (DAP for...
Description of activity and work performed
Local variabilities of DLP from two CT devices and DAP from three radiology tables were investigated using a bootstrapping method. Variabilities of national DLP-DRLs and DAP-DRLs were investigated according to the number of devices and sample size per device. Local and national variabilities were computed for common examinations (e.g. trunk, brain, lumbar spine) to ensure sufficient data. Variabilities for other procedures have to be considered but are expected to be higher than observed. No factors influencing the inherent variabilities (patient size, scanner type, diagnostic quality)...
Conclusion and recommendations
Variabilities on local and national dose metrics are high for CT and X-ray examinations. To reduce these uncertainties, collecting large samples of data with dose tracking software is mandatory and collecting data from all centres in the country is preferable.
Collecting 20 to 50 data per device is sufficient to establish national DRLs. However, hundreds of data are needed if comparison between local metrics and national DRLs is proceeded as part of the optimization process.
Countries with small amount of devices, less than 200, and...
T. Vanaudenhove; Federal Agency for Nuclear ControlBrussels/BE - nothing to disclose
S. Taylor; Centre Hospitalier Universitaire Ambroise Paré Mons/BE - nothing to disclose
A. van Muylem; Hôpital ErasmeBrussels/BE - nothing to disclose
P. A. Gevenois; Hôpital ErasmeBrussels/BE - nothing to disclose
D. Tack;Epicura hospital Baudour/BE - nothing to disclose
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 Vanaudenhove T, Van Muylem A, Howarth N, Gevenois...