Hanson W F, Grant W, Kennedy P, Cundiff J H, Gagnon W F, Berkley L W, Shalek R J
Med Phys. 1978 Nov-Dec;5(6):552-5. doi: 10.1118/1.594449.
One of the principal concerns of a physicist responsible for calibrating megavoltage radiotherapy equipment is the validity and stability of the 60Co exposure correction factor assigned to his ionization-chamber and electrometer system. It is the practice of the AAPM Radiological Physics Center (RPC) to perform an intercomparison between the RPC chamber and electrometer system and the chamber and electrometer in use at each of the various institutions visited by the RPC. The results of 202 such intercomparisons are reviewed to determine (1) the consistency in the assignment of exposure correction factors by a calibrating agency with itself and with other calibrating agencies, and (2) the dependence of the reliability of the exposure correction factors upon the type of field instrument and the time since calibration.
负责校准兆伏级放射治疗设备的物理学家主要关注的问题之一，是分配给其电离室和静电计系统的钴 - 60照射校正因子的有效性和稳定性。美国医学物理学家协会放射物理中心（RPC）的做法是，将RPC的电离室和静电计系统与RPC所访问的各机构中使用的电离室和静电计进行比对。对202次此类比对的结果进行审查，以确定：（1）校准机构自身以及与其他校准机构在照射校正因子分配上的一致性；（2）照射校正因子可靠性对现场仪器类型和校准后时间的依赖性。
