[Coral-List] testing effects of ocean acidification

[Peter Sale]

Hi all,
I just came across this paper, and have not yet read beyond the abstract, 
but it may be important to anyone doing research on effects of ocean 
acidification on coral reef organisms.  With the caveat that some 
statisticians are a bit over the top purists, but knowing that many 
ecologists (including me sometimes) are statistically over-casual, I think 
the abstract contains some telling comment.  Admittedly, this article is 
based on studies from all over, not just reefs, and we who work on reefs 
are far better than average scientists.  Still, would be nice to ensure we 
avoid sloppy science as we accumulate information on OA effects on our 
favorite system.

The article, by C. Cornwall and C. Hurd, out of UWA just came out in ICES: 
http://icesjms.oxfordjournals.org/content/early/2015/07/07/icesjms.fsv118.abstract

The part of the abstract that caught my eye says, with reference to 
aquarium or tank experiments, "To assess the use of appropriate 
experimental design in ocean acidification research, 465 studies published 
between 1993 and 2014 were surveyed, focusing on the methods used to 
replicate experimental units. The proportion of studies that had 
interdependent or non-randomly interspersed treatment replicates, or did 
not report sufficient methodological details was 95%. Furthermore, 21% of 
studies did not provide any details of experimental design, 17% of studies 
otherwise segregated all the replicates for one treatment in one space, 
15% of studies replicated CO2 treatments in a way that made replicates 
more interdependent within treatments than between treatments, and 13% of 
studies did not report if replicates of all treatments were randomly 
interspersed. As a consequence, the number of experimental units used per 
treatment in studies was low (mean = 2.0)."

Peter Sale
@PeterSale3
www.petersalebooks.com