1) How to not design a study. There is no control group!
2) How not to do scientific reporting. There was no critical thinking or fact checking involved in the writing of this piece. If there had been, the author would have noted that the lack of control group was a serious problem instead of pronouncing that yoga alters gene expression. They would have also noted that a similar study was recently published (and hyped) which noticed similar results between the practicing meditation and group therapy. [1]
"Our study design is composed of both prospective and > cross-
sectional features (Fig. S1). The prospective aspect of the study
involved enrolling 26 healthy subjects who had no prior RR-
eliciting experience (Novices, N1) which served as their own
controls. They then underwent 8 weeks of RR-eliciting training
(Short-term Practitioners, N2). The cross-sectional aspect of the
study involved enrolling another 26 healthy subjects who had
significant prior experience of regular RR-eliciting practice for 4–
20 years (Long-Term Practitioners, M) to be compared with
novices either before or after their 8-week RR training."
Then
"We collected blood samples and biological measures when study
subjects attended morning laboratory sessions, during which M
and N2 listened to a 20-minute RR-eliciting CD and N1 listened
to a 20-minute health education CD (control)"
So if I understand correctly, it means the "novices" went through :
* a period of time during which their blood was tested before, shortly after and then later after doing basically nothing
* a period of time during which their blood was tested before, shortly after and then later after doing meditation/yoga/whatever
The same experiment being done with people with more experience.
I'm no researcher, so I'm curious what would be an acceptable control group for this experiment ?
A group of novices that would gets their blood tested before/after doing nothing at all (sleep ? another activity ?)
Is it the fact that the same person serves as its own control (by doing different experiments over time) that invalidates it ?
" ... Prior to starting their training, the participants went through what was essentially a control group session -- blood samples were taken before and immediately after they listened to a 20-minute health education CD and again 15 minutes later. After completing the training course, a similar set of blood tests was taken before and after participants listened to a 20-minute CD used to elicit the relaxation response as part of daily practice. ... "
Not sure if that really counts by your standards, but thought you'd be interested in the info nonetheless.
1) How to not design a study. There is no control group!
2) How not to do scientific reporting. There was no critical thinking or fact checking involved in the writing of this piece. If there had been, the author would have noted that the lack of control group was a serious problem instead of pronouncing that yoga alters gene expression. They would have also noted that a similar study was recently published (and hyped) which noticed similar results between the practicing meditation and group therapy. [1]
[1] http://onlinelibrary.wiley.com/doi/10.1002/cncr.29063/full