送交者: chouqilozi 于 2008-11-04, 13:11:56:

回答: 把许多同卵双胞胎分为两组 由 HunHunSheng 于 2008-11-04, 12:59:17:

• What bias? (无内容) - HunHunSheng (0 bytes) 2008-11-04, 13:15:19 (271482)
  • the fact that the 2nd group are survivors of more years than the 1st group. (无内容) - chouqilozi (0 bytes) 2008-11-04, 13:18:29 (271483)
    • 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)

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