Hi all:
I have a question about the sample size calculation.
It's a pilot study,which includes 2 groups(low,high),3 time point(3,6,9
monthes).Each person has 3 results which according to the
3 time points.So it's a longitudinal study.
I want to calculate the minimum sample size from the pilot study, but can't
find the solution since the data is highly skewed and
it's a longitudinal study or multi-level model,which can't use common
algorithm.
Any suggestions from you are welcome.
The demo data is as follow:
id group time result
a low 3 0
a low 6 0
a low 9 3
b low 3 0
b low 6 0
b low 9 5
c high 3 0
c high 6 10
c high 9 80
d high 3 50
d high 6 65
d high 9 100
... ...
Thanks for your help.
My best.
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