However, the event rates of many of these outcomes is low in the reported trials making reliable estimates of treatment effect impossible.

不过，这些预后的发生率在报告的试验中发生率低，而使得可信的评估治疗成效是不可能的。

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Supreme Court rulings are famously impossible to predict, but there are several likely outcomes.

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Bad lawyers are very good at explaining away unfavorable outcomes to clients, and suing lawyers for malpractice is virtually impossible.

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Because each of these three potential outcomes represents a very real possibility, it has become nearly impossible to predict where tax rates will be come January.

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