检验标本周转时间(turn around time,TAT)又称回报时间,是衡量临床实验室报告及时性的一个重要指标。TAT的定义分为广义和狭义,广义的TAT是指从医师医嘱申请检验项目到获得检验报告的全部时间,包括项目申请、采集及运输样本、实验室分析检测等全过程[1]。但项目申请、采集及运输样本都是检验科的不可控环节,所以在统计分析TAT时,运用 Turn around time (TAT), also known as payback time, is an important measure of the timeliness of clinical laboratory reporting. The definition of TAT is divided into generalized and narrow sense. The generalized TAT refers to the entire process of applying the test items from the doctor’s order to obtaining the test report, including project application, sample collection and transportation, and laboratory analysis and testing [1]. However, the project application, collection and transportation samples are uncontrollable links of the laboratory, so in the statistical analysis of TAT, the use of