Valenstein P N, Emancipator K
Department of Pathology, State University of New York at Stony Brook 11794-8691.
Am J Clin Pathol. 1989 Apr;91(4):452-7. doi: 10.1093/ajcp/91.4.452.
The authors studied the performance of four measures of laboratory turnaround time: the mean, median, 90th percentile, and proportion of tests reported within a predetermined cut-off interval (proportion of acceptable tests [PAT]). Measures were examined with the use of turnaround time data from 11,070 stat partial thromboplastin times, 16,761 urine cultures, and 28,055 stat electrolyte panels performed by a single laboratory. For laboratories with long turnaround times, the most important quality of a turnaround time measure is high reproducibility, so that improvement in reporting speed can be distinguished from random variation resulting from sampling. The mean was found to be the most reproducible of the four measures, followed by the median. The mean achieved acceptable precision with sample sizes of 100-500 tests. For laboratories with normally rapid turnaround times, the most important quality of a measure is high sensitivity and specificity for detecting whether turnaround time has dropped below standards. The PAT was found to be the best measure of turnaround time in this setting but required sample sizes of at least 500 tests to achieve acceptable accuracy. Laboratory turnaround time may be measured for different reasons. The method of measurement should be chosen with an eye toward its intended application.
均值、中位数、第90百分位数以及在预定截止间隔内报告的检测比例（可接受检测比例[PAT]）。利用来自单一实验室进行的11,070次急诊部分凝血活酶时间检测、16,761次尿培养检测以及28,055次急诊电解质检测的周转时间数据，对这些指标进行了考察。对于周转时间较长的实验室，周转时间测量指标最重要的特性是高重现性，以便能够区分报告速度的提高与抽样导致的随机变异。结果发现，均值是这四种指标中重现性最高的，其次是中位数。样本量为100 - 500次检测时，均值达到了可接受的精密度。对于周转时间通常较快的实验室，测量指标最重要的特性是对检测周转时间是否降至标准以下具有高灵敏度和特异性。结果发现，在这种情况下，PAT是周转时间的最佳测量指标，但需要至少500次检测的样本量才能达到可接受的准确度。测量实验室周转时间可能有不同的原因。应根据其预期用途来选择测量方法。
