observational study

基本解釋

But the authors acknowledged that they could not account for all possible variables, and cautioned that it was an observational study that draws no conclusions about cause and effect.
不過，作者們承認(rèn)未能一一證明所有可能的變化因素，并提醒這是項(xiàng)觀察研究，不能就此得出這兩者之間存在因果關(guān)系的結(jié)論。
We used to think that hormone-replacement therapy reduced the risk of heart attacks by around half, for example, because this was the finding of a small trial, and a large observational study.
例如，我們曾相信激素替代療法能把心臟病發(fā)的風(fēng)險降低近一半，但是這種療法大多源于觀察性研究，極少基于臨床試驗(yàn)。
In June, Northwestern University researchers released the results of the longest observational study ever to investigate the relationship between aerobic fitness and the development of diabetes.
六月，西北大學(xué)（Northwestern University）研究人員公布了以往調(diào)查有氧健身和糖尿病發(fā)病之間關(guān)系的最長期觀察研究的結(jié)果。

Last week, the Lancet published the combined results of a larger observational study, also led by Professor Rothwell.
It was an observational study.

No previous long-term observational study had collected both environmental and biomedical information starting in utero.
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In an observational study like this, however, it is always possible that there is a difference between the women who decided to take hormones and those who had not.
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