Last year known skeptic Ben Goldacre talked about medical science on TED and how negative results are often not reported in scientific journals (http://www.youtube.com/watch?v=RKmxL8VYy0M).
This talk made me think about medical science in general and the use of meta analysis which seems to be the corner stone of modern medicine. I'm not a natural scientist and as such not an expert on statistics, but the whole idea of meta analysis strikes me as unscientific. I understand that it might be the only method available at times, but it seems very strange that medical science has adopted meta analysis as a basic concept. To me it sounds like medical researchers have adopted an attitude of "fix it later". Or in other words, they don't even try to conduct studies that are reliable on their own. I can't help to think that corporate interests might have something to do with this. Have we created a system where economical interests are more important than reliable results?
It would be interesting to hear from people with experience in this field what sample sizes, margins of error, confidence levels and other statistical properties are deemed acceptable within medical science. In my opinion the strong emphasis on meta analysis seems to indicate that medical science is not characterized by scientific rigorousity.