But in trying to answer this question with these methods, a host of background factors come into play and we are then left to relying on statistical controls in any attempts to sort them.
但是在用这些方法回答这个问题时，大量背景因素开始起作用，然后我们就开始依靠统计管理来解决他们。
2
He questioned the statistical methods used in the paper and said the authors had not adequately considered other factors that might have been responsible for the fall in child deaths.
他对论文中使用的统计方法提出了质疑，认为研究者没有充分考虑到可能引起儿童死亡率下降的其他因素。
3
They then used statistical controls to filter out such factors.