It first appeared in 1967, the "Berne Convention" Stockholm text, expressed as a result of the three conditions, so it is called three-step test.

它最早出现在1967年的《伯尔尼公约》斯德哥尔摩文本中，因表述为三个条件，故被称为三步检验法。

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The next step, typically, would have been to do a second-stage test (of three required phases) on a few hundred patients to confirm early results, proceeding later with costlier and bigger final-stage trials in thousands of people.

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