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发帖数: 1350 | 1 假设下面一个crossover design：
subject, random effect
renal site, fixed effect
drug treatment, fixed effect
SAS linear mixed model is as follows (no interaction effect of site and drug
):
proc mixed data=tmp cl;
class subject site drug;
model diff=site drug / ddfm=kr cl;
random subject;
run;
在crossover design的情况下，作linear mixed model后，如何计算inter-subject
and intra-subject coefficient of variation? 我看到下面这个blog提到intra-
subject coefficient of variation的计算：
http://onbiostatistics.blogspot.com/2014/03/intra-subject-coeff
但是找不到如何算inter-subject coefficient of variation。我看到有人直接用
square root of between-subject variance divided by the overall mean作为inter
-subject coefficient of variation，这个在crossover design的上下文里面对吗？
如果这个对，那么intra-subject coefficient of variation是不是也可以用同样的方
法计算呢？在SAS PROC MIXED output里面，between-subject variance和within-
subject variance是不是就是“Covariance Parameter Estimates”下面的Estimates
，其中“Subject”对应between-subject variance，“Residual”对应within-
subject variance？可是我试着用这个“Residual”值算了一下，和上面的blog里面提
供的公式算出来的不一样。 |
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