the fact that the 2nd group are survivors of more years than the 1st group.

the fact that the 2nd group are survivors of more years than the 1st group.

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送交者: chouqilozi 于 2008-11-04, 13:18:29:

回答: What bias? 由 HunHunSheng 于 2008-11-04, 13:15:19:

Then delete anyone from the study who died before 50 (无内容) - HunHunSheng (0 bytes) 2008-11-04, 13:26:02 (271486)
- yes, this is fine, I overlooked that they are identical twins. (无内容) - chouqilozi (0 bytes) 2008-11-04, 13:31:20 (271489)
- Or consider those in 2nd group who died before 40 - HunHunSheng (52 bytes) 2008-11-04, 13:27:26 (271487)