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Negative Controls: A Tool for Detecting Confounding and Bias in Observational Studies

A negative control exposure B should be an exposure such that the common causes of A and Y are as nearly ......

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一朋友女朋友即將到國外出差,走之前說給他把屋子換一個新床。他高興的不行,天天拉著我們吹噓他女朋友對他有多好。結果貨一到,他抱著我就淚奔了。。。哭的那個慘呀。。。...

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