Reference Values for Diagnostic Radiology: Application and Impact

TLDR

Reference values (RVs) recommended by the American Association of Physicists in Medicine for four radiographic modalities are derived from nationwide surveys and represent the 80th percentile of dose distributions, enabling comparison of individual equipment doses with national benchmarks. The study aims to promote annual measurement of radiation doses for specific projections using standard phantoms, as recommended by the American College of Radiology. If a device exceeds its RV, the medical physicist investigates the cause with the radiologist and decides whether to justify the dose or optimize the system to lower patient exposure. Equipment exceeding RVs delivers higher doses than 80% of surveyed units, and RVs serve as a useful tool for comparing patient doses and assessing equipment performance across U.S.

Abstract

Reference values (RVs) are recommended by the American Association of Physicists in Medicine for four radiographic projections, computed tomography, fluoroscopy, and dental radiography. RVs are used to compare radiation doses from individual pieces of radiographic equipment with doses from similar equipment assessed in national surveys. RVs recommended by the American Association of Physicists in Medicine have been developed from the Nationwide Evaluation of X-ray Trends survey performed by the state radiation protection agencies with the cooperation and support of the U.S. Food and Drug Administration, the Conference of Radiation Control Program Directors, and the American College of Radiology. The RVs selected by the American Association of Physicists in Medicine represent, approximately, the 80th percentile of the survey distributions. Consequently, equipment exceeding the RVs is using higher radiation doses than is 80% of the equipment in the surveys. Radiation doses for specific projections, with standard phantoms, should be measured annually, as recommended by the American College of Radiology. When the RVs are exceeded, the medical physicist should investigate the cause and determine, in cooperation with the responsible radiologist, whether these doses are justified or the imaging system should be optimized to reduce patient radiation doses. RVs are a useful tool for comparing patient radiation doses at institutions throughout the United States and for providing information about radiographic equipment performance.