Research has found that IQ predicted leadership skills when the tests were given under low stress conditions，but under high stress conditions，IQ was negatively correlated with leadership—that is, it predicted the opposite.

研究发现，在压力小的情况下，智商可以预测领导能力；但在压力大的情况下，智商与领导能力呈负相关，也就是说，它预测的结果正好相反。

插入成分 that is，用于引导解释前文的意思，很正确的。

含义是：在紧要关头，智商高的人反而没有领导能力了。