Tofani Alessandro, Imbordino Patrizia, Lecci Antonio, Bonannini Claudia, Del Corona Alberto, Pizzi Stefano
Unità Operativa di Fisica Sanitaria, Azienda USL N. 6, Livorno, Italy.
Radiol Med. 2003 May-Jun;105(5-6):490-9.
The physical quality index (QI) of radiological devices summarises in a single numerical value between 0 and 1 the results of constancy tests. The aim of this paper is to illustrate the results of the use of such an index on all public radiological devices in the Livorno province over one year.
The quality index was calculated for 82 radiological devices of a wide range of types by implementing its algorithm in a spreadsheet-based software for the automatic handling of quality control data.
The distribution of quality index values was computed together with the associated statistical quantities. This distribution is strongly asymmetrical, with a sharp peak near the highest QI values. The mean quality index values for the different types of device show some inhomogeneity: in particular, mammography and panoramic dental radiography devices show far lower quality than other devices. In addition, our analysis has identified the parameters that most frequently do not pass the quality tests for each type of device. Finally, we sought some correlation between quality and age of the device, but this was poorly significant.
The quality index proved to be a useful tool providing an overview of the physical conditions of radiological devices. By selecting adequate QI threshold values for, it also helps to decide whether a given device should be upgraded or replaced. The identification of critical parameters for each type of device may be used to improve the definition of the QI by attributing greater weights to critical parameters, so as to better address the maintenance of radiological devices.
放射设备的物理质量指标（QI）用一个介于0和1之间的数值总结了稳定性测试的结果。本文的目的是说明在一年时间里，该指标在里窝那省所有公共放射设备上的使用结果。
通过在一个基于电子表格的软件中实施其算法，对82台各种类型的放射设备计算质量指标，该软件用于自动处理质量控制数据。
计算了质量指标值的分布以及相关的统计量。这种分布强烈不对称，在最高QI值附近有一个尖峰。不同类型设备的平均质量指标值显示出一些不均匀性：特别是，乳腺摄影和全景牙科放射摄影设备的质量远低于其他设备。此外，我们的分析确定了每种类型设备最常未通过质量测试的参数。最后，我们寻找了质量与设备使用年限之间的一些相关性，但这种相关性很弱。
质量指标被证明是一个有用的工具，可提供放射设备物理状况的概述。通过为其选择适当的QI阈值，它还有助于决定是否应升级或更换某一给定设备。确定每种类型设备的关键参数可用于通过赋予关键参数更大权重来改进QI的定义，从而更好地进行放射设备的维护。
