Audit Programmes in a Diagnostic Radiological Facility

The effective implementation of optimisation strategies for radiation protection in diagnostic radiology including nuclear medicine requires mechanisms for ongoing audit of all relevant factors. The Quality Criteria of the Commission of European Communities highlights clearly the three aspects of a radiological examination which needed to be considered, which are: (i) radiographic technique, (ii) patient dose, and (iii) image quality. Therefore, it is important that the choice of a known and acceptable radiographic technique provides a known outcome in terms of patient dose and image quality. This requirement should be capable of being achieved throughout Europe and capable of being updated as new radiological strategies are developed. Audit programmes aimed at monitoring that this situation exists may be considered at three levels: Level 1 involves routine, periodic, assessment of patient doses on a representative sample of patients undergoing a particular type of examination. Results from this audit are then compared with acceptable and clearly defined diagnostic reference levels or reference dose values which provides a framework for guidance on acceptable practice. A summary of such level 1 programmes which are being pursued in Europe is presented. Level 2 audit programmes, beside patient dose assessment, will also involve an assessment of all those parameters relevant to an X ray examination which may have a bearing on the actual dose delivered to the patient. Such level 2 audit programmes provide the basis for implementation of optimisation strategies for radiation protection in terms of risk reduction, one of the fundamental tenets of radiation protection philosophy. Level 3 audit programmes also include assessment and verification of image quality requirements for particular examinations. This latter aspect is a necessary basis for overall optimisation of radiation protection in diagnostic radiology.