Originally posted by Octavius Thats just it though Myelo. How controlled is it? [/i]
Very controlled. The only looked at placebo controlled studies. In scientific terms, this is the bestest controlled there is.
Originally posted by Octavius I think genetics certainly has something [not everything] to do with susceptability to colds, heart disease, obesity, etc. Unless both groups had identical genetic makeup, then the results of the studies blaming a certain vitamin can be described as more random or chaotic than anything. If you randomize randomness, you get random. [/i]
No and no. I'm not sure you understand how these studies work so I'll try to explain.
You take a group of patients and randomly assigned them to get either Vitamin E (treated group) or a fake pill (control group). You follow them and see what happens in each group.
That way each patient has the same probability of receiving one treatment or the other. This ensures that all factors affecting outcome should be distributed randomly and equally between the treated and control groups.
Each individual patient doesn’t need to be genetically identical because you aren’t comparing individuals. You are comparing the two groups. So as long as each
group is equal, any difference in outcome is likely due to the only thing that is different – whether they got Vitamin E or a placebo.
Now, you need to make sure the groups are large enough that any difference between the groups is not due to chance alone. There are mathematical ways to do this and these results are always reported in the study. For example, they may something like this:
The patients that got Vitamin E were 3% more likely to die in 5 years than the placebo group (p=0.027). This means there is a 2.7% chance that the difference in death between the two groups was due to chance, not the treatment. In other words we can be pretty sure that the difference is due to the Vitamin E.
For the exact details, here is the
study
