Hunter W J, Lingk W, Recht P
J Assoc Off Anal Chem. 1979 Jul;62(4):864-73.
In 1977, the Commission of the European Communities initiated an intercomparison study to determine the single administration oral LD50 value in rats of each of 5 chemicals with the aims of comparing experimentation technologies, determining the degree of variation in the results and the various parameters used to establish the LD50 value, and establishing a common protocol for the determination of the LD50 value. Sixty-five laboratories in 8 countries took part in the first study. The significant variation in protocol may have led to the large interlaboratory variation observed in the results. Therefore, participating laboratories carried out a second study using a common protocol, preceded by a pilot study. A total of 100 laboratories in 13 countries participated. A majority of results of the second study are currently being analyzed, and the indications are that the interlaboratory variation has been significantly reduced.
1977年，欧洲共同体委员会发起了一项比对研究，以确定5种化学品中每种化学品对大鼠的单次经口半数致死剂量（LD50）值，目的是比较实验技术，确定结果的变异程度以及用于确定LD50值的各种参数，并建立确定LD50值的通用方案。8个国家的65个实验室参与了首次研究。实验方案的显著差异可能导致了研究结果中观察到的较大实验室间差异。因此，参与实验室在进行初步研究之后，使用通用方案开展了第二次研究。13个国家的100个实验室参与了此次研究。目前正在对第二次研究的大部分结果进行分析，有迹象表明实验室间差异已显著降低。
