It's just that you had such a massive confounding variable that it totally threw off your analysis.

只是混淆变量过大，以至于使分析完全偏离。

In order to conduct a clinical trial properly, scientists need to be able to minimize interference from confounding variables, things that influence final measurements, without being the variable of interest.

为了正确地进行临床试验，科学家们需要能够最大限度地减少来自混杂变量的干扰——这些变量影响最终测量，而不是兴趣变量。