Statistics of embryonic stem cell research?

I have been doing some reading of the various journal articles on esc research and have discovered that a lot of times their statistical analysis is flawed (I'm a mathematician, not a clinical researcher). For example, if an experiment studied 20 rats and 8 of them died, most of the time the result of those 8 rats are not included in the final analysis, showing a much higher rate of "cure" than there actualy was. Has anyone else noticed this? Has anyone done a literature review to see if this is prevailant in the science literature? Could I just have had too small of a sample of the literature?

Statistics of embryonic stem cell research?
In medical research it is common to remove subjects from a study. In clinical trials the mortality of the subject could be the result from a factor other than the treatment. For instance if radiation is used on the subjects to knock out their bone marrow to be replaced with esc donor material, and the subject dies of radiation related reasons, the subject could be discounted. The donor material was not the issue in the death of the subject. In human trials the most common answer is non-compliance with some aspect of treatment.





In all the literature there should be a footnote, or even a paragraph, as to why the subjects were removed. Some journals do not print the full study and the abridged version may lack the finer details needed to be mathematically correct.





Should you decide to tackle a literature review I would suggest getting raw data from the researchers and interviewing them on their statistical methods. It will become clearer as to why particular subjects were removed.
Reply:G'day Sophia,





Thank you for your question.





I haven't looked much of the journal articles as opposed to reports in the popular press.





If you think that there is a trend there, you should look at it as a project. If the statistical analysis was flawed in some of the findings, that should have some impact on consideration of this controversial topic.





Regards