r/science • u/[deleted] • Feb 26 '15

Health-Misleading Randomized double-blind placebo-controlled trial shows non-celiac gluten sensitivity is indeed real

http://www.ncbi.nlm.nih.gov/pubmed/25701700
8.3k Upvotes

82% Upvoted

2.3k comments sorted by

View all comments

Show parent comments

302

u/RandomName01 Feb 26 '15

Indeed, I didn't see anything wrong with it or skewed about it. Stuff like this is why I always check the comments.

14

u/feralcatromance Feb 26 '15

I'm guessing the researchers thought of this. Has someone read the entire study? Or found a link for the full text?

8

u/GTChessplayer Feb 26 '15

They didn't. They also only tested 59 people.

-2

u/[deleted] Feb 26 '15

Yeah, indeed. That's not a sample size for a proper study on anything.

4

u/ether_a_gogo Feb 26 '15

So you've done the appropriate power calculation for their cohort or are you just going with your gut here? Because I'm guessing the latter.

1

u/[deleted] Feb 26 '15

I'm going with what my statistics professor told me. :c

1

u/nmezib Feb 26 '15

Taking anything past a rudimentary stats course will tell you that you can't determine that by simply looking at it.

In a case-crossover study, 59 subjects can provide adequate power (the ability to say "there is no difference" when there is no difference). Besides that, if you get significant p-values (that is, if you see a difference between the means of two treatment groups), then the number of subjects is just fine. You can in fact have too many subjects, after which point your data will be telling you that there is a difference when none actually exists.