Significant ≠ relevant [Design Issues]
Dear All!
I noticed it became fashionably for russian regulatories to ask to include group effect in the analyses even if in the protocal were stated the abovementioned rules. There are some more detailed situations when we were asked to take the effects into the ANOVA model. First is when the study is divided not only by groups by logystical reasons, but by groups by some other reasons (namely, different blood collection schemes). And the second is when there were drop-outs in the study and subjects were replaced by doubles (the date of the visit was to be included into the statistical model). I think that including term to ANOVA to prove it's significance is a bit naive because the true reasons may be various ("We shall see what we shall see"). What is your opinion on that topic?
And some practical questions:
Grateful for your answers!
I noticed it became fashionably for russian regulatories to ask to include group effect in the analyses even if in the protocal were stated the abovementioned rules. There are some more detailed situations when we were asked to take the effects into the ANOVA model. First is when the study is divided not only by groups by logystical reasons, but by groups by some other reasons (namely, different blood collection schemes). And the second is when there were drop-outs in the study and subjects were replaced by doubles (the date of the visit was to be included into the statistical model). I think that including term to ANOVA to prove it's significance is a bit naive because the true reasons may be various ("We shall see what we shall see"). What is your opinion on that topic?
And some practical questions:
- Which ANOVA model should be preffered in that cases Group, Group x Sequence or... ? (would be very grateful for link)?
- As I understand the residual variance depends on the quantity of terms (and even the more number of terms the less residual). Can we perform 2 different ANOVA models: first to exclude group effect, and second - to make a standard treatm+period+seq+sub(seq) calcaulation?
- What if we do get significant group term? Can we somehow make sure that number of subjects from only one group is sufficient for the study? What else can we take in such a case?
Grateful for your answers!
—
"Being in minority, even a minority of one, did not make you mad"
"Being in minority, even a minority of one, did not make you mad"
Complete thread:
- Study conduct in groups Smitha 2015-02-02 04:21 [Design Issues]
- Study conduct in groups ElMaestro 2015-02-02 08:21
- Study conduct in groups Helmut 2015-02-02 13:08
- Study conduct in groups Smitha 2015-02-04 04:30
- Study conduct in groups Helmut 2015-02-04 12:57
- Study conduct in groups felipeberlinski 2015-02-04 22:36
- Study conduct in groups ElMaestro 2015-02-04 23:58
- Significant ≠ relevant Helmut 2015-02-05 00:49
- Significant ≠ relevantAstea 2016-03-24 20:10
- Significant ≠ relevant ElMaestro 2016-03-24 23:12
- Significant ≠ relevant zizou 2016-03-25 21:41
- Loss of power etc. Helmut 2016-03-26 14:46
- Loss of power etc. Astea 2016-03-27 21:18
- Loss of power etc. zizou 2016-03-27 23:44
- Combined power? Helmut 2016-03-28 14:29
- Loss of power etc. Astea 2016-03-28 23:57
- Loss of power etc. ElMaestro 2016-03-29 00:16
- Mystery Helmut 2016-03-29 17:28
- Back to the Future Astea 2016-03-29 21:57
- Back to the Future ElMaestro 2016-03-29 23:11
- Using lectures != Reading them mittyri 2016-03-30 00:17
- Back to the Future ElMaestro 2016-03-29 23:11
- Back to the Future Astea 2016-03-29 21:57
- Loss of power etc. Helmut 2016-03-26 14:46
- Significant ≠ relevantAstea 2016-03-24 20:10
- Study conduct in groups felipeberlinski 2015-02-04 22:36
- Study conduct in groups Helmut 2015-02-04 12:57
- Study conduct in groups Smitha 2015-02-04 04:30