l*****i
发帖数: 43 | 1 i am a new comer, my boss asked me to get the sample size for a clinical
trial, however, using my way, i can not get the number the former
statistician got. anyone has an idea how she got it?
1. alpha=0.05
2. power=80%
3. my boss wants 10% drug effect (she didn't explain in detail what this
mean, i assume it is after medication, the score drops 10% more than control
, because the lower the score, the better the treatment).
4. population mean drop is -0.17 (it is a score to evaluate mental function,
total score is 30), SD is 1.45 (she didn't explain what is this sd, is this
the sd of average dropping in the score, or the sd of the score）.
the former statistician got a sample size of 703.
Can anyone get this number?
3ks | a*****3
发帖数: 601 | | s**f
发帖数: 365 | 3 用这个算吧
http://www.stat.uiowa.edu/~rlenth/Power/
control
function,
this
【在 l*****i 的大作中提到】
: i am a new comer, my boss asked me to get the sample size for a clinical
: trial, however, using my way, i can not get the number the former
: statistician got. anyone has an idea how she got it?
: 1. alpha=0.05
: 2. power=80%
: 3. my boss wants 10% drug effect (she didn't explain in detail what this
: mean, i assume it is after medication, the score drops 10% more than control
: , because the lower the score, the better the treatment).
: 4. population mean drop is -0.17 (it is a score to evaluate mental function,
: total score is 30), SD is 1.45 (she didn't explain what is this sd, is this
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